Receptors, Antigen, B-Cell: IMMUNOGLOBULINS on the surface of B-LYMPHOCYTES. Their MESSENGER RNA contains an EXON with a membrane spanning sequence, producing immunoglobulins in the form of type I transmembrane proteins as opposed to secreted immunoglobulins (ANTIBODIES) which do not contain the membrane spanning segment.Antibodies: Immunoglobulin molecules having a specific amino acid sequence by virtue of which they interact only with the ANTIGEN (or a very similar shape) that induced their synthesis in cells of the lymphoid series (especially PLASMA CELLS).B-Lymphocytes: Lymphoid cells concerned with humoral immunity. They are short-lived cells resembling bursa-derived lymphocytes of birds in their production of immunoglobulin upon appropriate stimulation.Antibody Specificity: The property of antibodies which enables them to react with some ANTIGENIC DETERMINANTS and not with others. Specificity is dependent on chemical composition, physical forces, and molecular structure at the binding site.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.B-Lymphocyte Subsets: A classification of B-lymphocytes based on structurally or functionally different populations of cells.Antibodies, Viral: Immunoglobulins produced in response to VIRAL ANTIGENS.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Antigens, CD79: A component of the B-cell antigen receptor that is involved in B-cell antigen receptor heavy chain transport to the PLASMA MEMBRANE. It is expressed almost exclusively in B-LYMPHOCYTES and serves as a useful marker for B-cell NEOPLASMS.Receptors, Antigen, T-Cell: Molecules on the surface of T-lymphocytes that recognize and combine with antigens. The receptors are non-covalently associated with a complex of several polypeptides collectively called CD3 antigens (ANTIGENS, CD3). Recognition of foreign antigen and the major histocompatibility complex is accomplished by a single heterodimeric antigen-receptor structure, composed of either alpha-beta (RECEPTORS, ANTIGEN, T-CELL, ALPHA-BETA) or gamma-delta (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA) chains.Pre-B Cell Receptors: Membrane proteins in precursor B-LYMPHOCYTES (pre-B Cells). They are composed of membrane-bound MU IMMUNOGLOBULIN HEAVY CHAINS in complex with SURROGATE LIGHT CHAINS instead of conventional IMMUNOGLOBULIN LIGHT CHAINS. Only successful rearrangement of the VDJ segments, at the Ig heavy chain gene locus (IMMUNOGLOBULIN HEAVY CHAIN GENES), will generate mu heavy chains that can pair with surrogate light chains. Thus formation of the pre-B cell receptors is an important checkpoint in the development of mature B cells.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Immunoglobulin M: A class of immunoglobulin bearing mu chains (IMMUNOGLOBULIN MU-CHAINS). IgM can fix COMPLEMENT. The name comes from its high molecular weight and originally being called a macroglobulin.Lymphocyte Activation: Morphologic alteration of small B LYMPHOCYTES or T LYMPHOCYTES in culture into large blast-like cells able to synthesize DNA and RNA and to divide mitotically. It is induced by INTERLEUKINS; MITOGENS such as PHYTOHEMAGGLUTININS, and by specific ANTIGENS. It may also occur in vivo as in GRAFT REJECTION.Antibody Formation: The production of ANTIBODIES by proliferating and differentiated B-LYMPHOCYTES under stimulation by ANTIGENS.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Antibodies, Bacterial: Immunoglobulins produced in a response to BACTERIAL ANTIGENS.Antibodies, Anti-Idiotypic: Antibodies which react with the individual structural determinants (idiotopes) on the variable region of other antibodies.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Antibodies, Neutralizing: Antibodies that reduce or abolish some biological activity of a soluble antigen or infectious agent, usually a virus.T-Lymphocytes: Lymphocytes responsible for cell-mediated immunity. Two types have been identified - cytotoxic (T-LYMPHOCYTES, CYTOTOXIC) and helper T-lymphocytes (T-LYMPHOCYTES, HELPER-INDUCER). They are formed when lymphocytes circulate through the THYMUS GLAND and differentiate to thymocytes. When exposed to an antigen, they divide rapidly and produce large numbers of new T cells sensitized to that antigen.Mice, Inbred C57BLAntibody Affinity: A measure of the binding strength between antibody and a simple hapten or antigen determinant. It depends on the closeness of stereochemical fit between antibody combining sites and antigen determinants, on the size of the area of contact between them, and on the distribution of charged and hydrophobic groups. It includes the concept of "avidity," which refers to the strength of the antigen-antibody bond after formation of reversible complexes.Mice, Inbred BALB CMice, Transgenic: Laboratory mice that have been produced from a genetically manipulated EGG or EMBRYO, MAMMALIAN.Base Sequence: The sequence of PURINES and PYRIMIDINES in nucleic acids and polynucleotides. It is also called nucleotide sequence.Epitopes: Sites on an antigen that interact with specific antibodies.Sialic Acid Binding Ig-like Lectin 2: A lectin and cell adhesion molecule found in B-LYMPHOCYTES. It interacts with SIALIC ACIDS and mediates signaling from B-CELL ANTIGEN RECEPTORS.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Fluorescent Antibody Technique: Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Spleen: An encapsulated lymphatic organ through which venous blood filters.Receptors, Antigen, T-Cell, alpha-beta: T-cell receptors composed of CD3-associated alpha and beta polypeptide chains and expressed primarily in CD4+ or CD8+ T-cells. Unlike immunoglobulins, the alpha-beta T-cell receptors recognize antigens only when presented in association with major histocompatibility (MHC) molecules.Antigens, CD: Differentiation antigens residing on mammalian leukocytes. CD stands for cluster of differentiation, which refers to groups of monoclonal antibodies that show similar reactivity with certain subpopulations of antigens of a particular lineage or differentiation stage. The subpopulations of antigens are also known by the same CD designation.Antigens, CD19: Differentiation antigens expressed on B-lymphocytes and B-cell precursors. They are involved in regulation of B-cell proliferation.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.Flow Cytometry: Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake.Immunoglobulin G: The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.Immunoglobulin Variable Region: That region of the immunoglobulin molecule that varies in its amino acid sequence and composition, and comprises the binding site for a specific antigen. It is located at the N-terminus of the Fab fragment of the immunoglobulin. It includes hypervariable regions (COMPLEMENTARITY DETERMINING REGIONS) and framework regions.Viral Envelope Proteins: Layers of protein which surround the capsid in animal viruses with tubular nucleocapsids. The envelope consists of an inner layer of lipids and virus specified proteins also called membrane or matrix proteins. The outer layer consists of one or more types of morphological subunits called peplomers which project from the viral envelope; this layer always consists of glycoproteins.Antigens: Substances that are recognized by the immune system and induce an immune reaction.Autoantibodies: Antibodies that react with self-antigens (AUTOANTIGENS) of the organism that produced them.Binding Sites, Antibody: Local surface sites on antibodies which react with antigen determinant sites on antigens (EPITOPES.) They are formed from parts of the variable regions of FAB FRAGMENTS.Immunoglobulin D: An immunoglobulin which accounts for less than 1% of plasma immunoglobulin. It is found on the membrane of many circulating B LYMPHOCYTES.Gene Rearrangement, B-Lymphocyte: Ordered rearrangement of B-lymphocyte variable gene regions coding for the IMMUNOGLOBULIN CHAINS, thereby contributing to antibody diversity. It occurs during the differentiation of the IMMATURE B-LYMPHOCYTES.Cell Differentiation: Progressive restriction of the developmental potential and increasing specialization of function that leads to the formation of specialized cells, tissues, and organs.beta 2-Glycoprotein I: A 44-kDa highly glycosylated plasma protein that binds phospholipids including CARDIOLIPIN; APOLIPOPROTEIN E RECEPTOR; membrane phospholipids, and other anionic phospholipid-containing moieties. It plays a role in coagulation and apoptotic processes. Formerly known as apolipoprotein H, it is an autoantigen in patients with ANTIPHOSPHOLIPID ANTIBODIES.Antibodies, Antinuclear: Autoantibodies directed against various nuclear antigens including DNA, RNA, histones, acidic nuclear proteins, or complexes of these molecular elements. Antinuclear antibodies are found in systemic autoimmune diseases including systemic lupus erythematosus, Sjogren's syndrome, scleroderma, polymyositis, and mixed connective tissue disease.Germinal Center: The activated center of a lymphoid follicle in secondary lymphoid tissue where B-LYMPHOCYTES are stimulated by antigens and helper T cells (T-LYMPHOCYTES, HELPER-INDUCER) are stimulated to generate memory cells.Immunoglobulin Heavy Chains: The largest of polypeptide chains comprising immunoglobulins. They contain 450 to 600 amino acid residues per chain, and have molecular weights of 51-72 kDa.Mice, Knockout: Strains of mice in which certain GENES of their GENOMES have been disrupted, or "knocked-out". To produce knockouts, using RECOMBINANT DNA technology, the normal DNA sequence of the gene being studied is altered to prevent synthesis of a normal gene product. Cloned cells in which this DNA alteration is successful are then injected into mouse EMBRYOS to produce chimeric mice. The chimeric mice are then bred to yield a strain in which all the cells of the mouse contain the disrupted gene. Knockout mice are used as EXPERIMENTAL ANIMAL MODELS for diseases (DISEASE MODELS, ANIMAL) and to clarify the functions of the genes.Protein-Tyrosine Kinases: Protein kinases that catalyze the PHOSPHORYLATION of TYROSINE residues in proteins with ATP or other nucleotides as phosphate donors.B-Cell Activation Factor Receptor: A member of the tumor necrosis factor receptor superfamily that specifically binds B-CELL ACTIVATING FACTOR. It is found on B-LYMPHOCYTES and plays a role in maturation and survival of B-cells. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.Immunoglobulins: Multi-subunit proteins which function in IMMUNITY. They are produced by B LYMPHOCYTES from the IMMUNOGLOBULIN GENES. They are comprised of two heavy (IMMUNOGLOBULIN HEAVY CHAINS) and two light chains (IMMUNOGLOBULIN LIGHT CHAINS) with additional ancillary polypeptide chains depending on their isoforms. The variety of isoforms include monomeric or polymeric forms, and transmembrane forms (B-CELL ANTIGEN RECEPTORS) or secreted forms (ANTIBODIES). They are divided by the amino acid sequence of their heavy chains into five classes (IMMUNOGLOBULIN A; IMMUNOGLOBULIN D; IMMUNOGLOBULIN E; IMMUNOGLOBULIN G; IMMUNOGLOBULIN M) and various subclasses.Immunoglobulin Light Chains, Surrogate: An immunolglobulin light chain-like protein composed of an IMMUNOGLOBULIN VARIABLE REGION-like peptide (such as light chain like lambda5 peptide) and an IMMUNOGLOBULIN CONSTANT REGION-like peptide (such as Vpreb1 peptide). Surrogate light chains associate with MU IMMUNOGLOBULIN HEAVY CHAINS in place of a conventional immunoglobulin light chains to form pre-B cell receptors.Precursor Cells, B-Lymphoid: Lymphocyte progenitor cells that are restricted in their differentiation potential to the B lymphocyte lineage. The pro-B cell stage of B lymphocyte development precedes the pre-B cell stage.HIV Antibodies: Antibodies reactive with HIV ANTIGENS.Immunoglobulin mu-Chains: The class of heavy chains found in IMMUNOGLOBULIN M. They have a molecular weight of approximately 72 kDa and they contain about 57 amino acid residues arranged in five domains and have more oligosaccharide branches and a higher carbohydrate content than the heavy chains of IMMUNOGLOBULIN G.Cross Reactions: Serological reactions in which an antiserum against one antigen reacts with a non-identical but closely related antigen.Antigens, Differentiation, B-Lymphocyte: Membrane antigens associated with maturation stages of B-lymphocytes, often expressed in tumors of B-cell origin.Gene Rearrangement, B-Lymphocyte, Light Chain: Ordered rearrangement of B-lymphocyte variable gene regions coding for the kappa or lambda IMMUNOGLOBULIN LIGHT CHAINS, thereby contributing to antibody diversity. It occurs during the second stage of differentiation of the IMMATURE B-LYMPHOCYTES.Autoimmunity: Process whereby the immune system reacts against the body's own tissues. Autoimmunity may produce or be caused by AUTOIMMUNE DISEASES.Receptors, Complement 3d: Molecular sites on or in B-lymphocytes, follicular dendritic cells, lymphoid cells, and epithelial cells that recognize and combine with COMPLEMENT C3D. Human complement receptor 2 (CR2) serves as a receptor for both C3dg and the gp350/220 glycoprotein of HERPESVIRUS 4, HUMAN, and binds the monoclonal antibody OKB7, which blocks binding of both ligands to the receptor.Antigens, CD5: Glycoproteins expressed on all mature T-cells, thymocytes, and a subset of mature B-cells. Antibodies specific for CD5 can enhance T-cell receptor-mediated T-cell activation. The B-cell-specific molecule CD72 is a natural ligand for CD5. (From Abbas et al., Cellular and Molecular Immunology, 2d ed, p156)Hybridomas: Cells artificially created by fusion of activated lymphocytes with neoplastic cells. The resulting hybrid cells are cloned and produce pure MONOCLONAL ANTIBODIES or T-cell products, identical to those produced by the immunologically competent parent cell.Recombinant Proteins: Proteins prepared by recombinant DNA technology.Clone Cells: A group of genetically identical cells all descended from a single common ancestral cell by mitosis in eukaryotes or by binary fission in prokaryotes. Clone cells also include populations of recombinant DNA molecules all carrying the same inserted sequence. (From King & Stansfield, Dictionary of Genetics, 4th ed)Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Antigens, CD40: A member of the tumor necrosis factor receptor superfamily with specificity for CD40 LIGAND. It is found on mature B-LYMPHOCYTES and some EPITHELIAL CELLS, lymphoid DENDRITIC CELLS. Evidence suggests that CD40-dependent activation of B-cells is important for generation of memory B-cells within the germinal centers. Mutations of the gene for CD40 antigen result in HYPER-IGM IMMUNODEFICIENCY SYNDROME, TYPE 3. Signaling of the receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.Ligands: A molecule that binds to another molecule, used especially to refer to a small molecule that binds specifically to a larger molecule, e.g., an antigen binding to an antibody, a hormone or neurotransmitter binding to a receptor, or a substrate or allosteric effector binding to an enzyme. Ligands are also molecules that donate or accept a pair of electrons to form a coordinate covalent bond with the central metal atom of a coordination complex. (From Dorland, 27th ed)Membrane Proteins: Proteins which are found in membranes including cellular and intracellular membranes. They consist of two types, peripheral and integral proteins. They include most membrane-associated enzymes, antigenic proteins, transport proteins, and drug, hormone, and lectin receptors.Self Tolerance: The normal lack of the ability to produce an immunological response to autologous (self) antigens. A breakdown of self tolerance leads to autoimmune diseases. The ability to recognize the difference between self and non-self is the prime function of the immune system.Immunoglobulin Light Chains: Polypeptide chains, consisting of 211 to 217 amino acid residues and having a molecular weight of approximately 22 kDa. There are two major types of light chains, kappa and lambda. Two Ig light chains and two Ig heavy chains (IMMUNOGLOBULIN HEAVY CHAINS) make one immunoglobulin molecule.Neutralization Tests: The measurement of infection-blocking titer of ANTISERA by testing a series of dilutions for a given virus-antiserum interaction end-point, which is generally the dilution at which tissue cultures inoculated with the serum-virus mixtures demonstrate cytopathology (CPE) or the dilution at which 50% of test animals injected with serum-virus mixtures show infectivity (ID50) or die (LD50).Cell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Autoantigens: Endogenous tissue constituents that have the ability to interact with AUTOANTIBODIES and cause an immune response.Phosphorylation: The introduction of a phosphoryl group into a compound through the formation of an ester bond between the compound and a phosphorus moiety.Antigens, Surface: Antigens on surfaces of cells, including infectious or foreign cells or viruses. They are usually protein-containing groups on cell membranes or walls and may be isolated.Models, Immunological: Theoretical representations that simulate the behavior or activity of immune system, processes, or phenomena. They include the use of mathematical equations, computers, and other electrical equipment.Antigens, CD3: Complex of at least five membrane-bound polypeptides in mature T-lymphocytes that are non-covalently associated with one another and with the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL). The CD3 complex includes the gamma, delta, epsilon, zeta, and eta chains (subunits). When antigen binds to the T-cell receptor, the CD3 complex transduces the activating signals to the cytoplasm of the T-cell. The CD3 gamma and delta chains (subunits) are separate from and not related to the gamma/delta chains of the T-cell receptor (RECEPTORS, ANTIGEN, T-CELL, GAMMA-DELTA).Antigen-Antibody Complex: The complex formed by the binding of antigen and antibody molecules. The deposition of large antigen-antibody complexes leading to tissue damage causes IMMUNE COMPLEX DISEASES.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Molecular Weight: The sum of the weight of all the atoms in a molecule.Antibodies, Neoplasm: Immunoglobulins induced by antigens specific for tumors other than the normally occurring HISTOCOMPATIBILITY ANTIGENS.Epitopes, B-Lymphocyte: Antigenic determinants recognized and bound by the B-cell receptor. Epitopes recognized by the B-cell receptor are located on the surface of the antigen.Recombinant Fusion Proteins: Recombinant proteins produced by the GENETIC TRANSLATION of fused genes formed by the combination of NUCLEIC ACID REGULATORY SEQUENCES of one or more genes with the protein coding sequences of one or more genes.B-Cell Activating Factor: A tumor necrosis factor superfamily member that plays a role in the regulation of B-LYMPHOCYTE survival. It occurs as a membrane-bound protein that is cleaved to release an biologically active soluble form with specificity to TRANSMEMBRANE ACTIVATOR AND CAML INTERACTOR PROTEIN; B-CELL ACTIVATION FACTOR RECEPTOR; and B-CELL MATURATION ANTIGEN.Immunologic Memory: The altered state of immunologic responsiveness resulting from initial contact with antigen, which enables the individual to produce antibodies more rapidly and in greater quantity in response to secondary antigenic stimulus.Immunoglobulin Fab Fragments: Univalent antigen-binding fragments composed of one entire IMMUNOGLOBULIN LIGHT CHAIN and the amino terminal end of one of the IMMUNOGLOBULIN HEAVY CHAINS from the hinge region, linked to each other by disulfide bonds. Fab contains the IMMUNOGLOBULIN VARIABLE REGIONS, which are part of the antigen-binding site, and the first IMMUNOGLOBULIN CONSTANT REGIONS. This fragment can be obtained by digestion of immunoglobulins with the proteolytic enzyme PAPAIN.Enzyme-Linked Immunosorbent Assay: An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed.Protein Structure, Tertiary: The level of protein structure in which combinations of secondary protein structures (alpha helices, beta sheets, loop regions, and motifs) pack together to form folded shapes called domains. Disulfide bridges between cysteines in two different parts of the polypeptide chain along with other interactions between the chains play a role in the formation and stabilization of tertiary structure. Small proteins usually consist of only one domain but larger proteins may contain a number of domains connected by segments of polypeptide chain which lack regular secondary structure.Receptors, IgG: Specific molecular sites on the surface of various cells, including B-lymphocytes and macrophages, that combine with IMMUNOGLOBULIN Gs. Three subclasses exist: Fc gamma RI (the CD64 antigen, a low affinity receptor), Fc gamma RII (the CD32 antigen, a high affinity receptor), and Fc gamma RIII (the CD16 antigen, a low affinity receptor).Antibodies, Protozoan: Immunoglobulins produced in a response to PROTOZOAN ANTIGENS.Platelet Glycoprotein GPIb-IX Complex: Platelet membrane glycoprotein complex essential for normal platelet adhesion and clot formation at sites of vascular injury. It is composed of three polypeptides, GPIb alpha, GPIb beta, and GPIX. Glycoprotein Ib functions as a receptor for von Willebrand factor and for thrombin. Congenital deficiency of the GPIb-IX complex results in Bernard-Soulier syndrome. The platelet glycoprotein GPV associates with GPIb-IX and is also absent in Bernard-Soulier syndrome.Glycopeptides: Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.Lymphoma, B-Cell: A group of heterogeneous lymphoid tumors generally expressing one or more B-cell antigens or representing malignant transformations of B-lymphocytes.Immunoglobulin kappa-Chains: One of the types of light chains of the immunoglobulins with a molecular weight of approximately 22 kDa.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Blotting, Western: Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.Glycosylation: The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.Peptides: Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are linear polypeptides that are normally synthesized on RIBOSOMES.Antibody Diversity: The phenomenon of immense variability characteristic of ANTIBODIES. It enables the IMMUNE SYSTEM to react specifically against the essentially unlimited kinds of ANTIGENS it encounters. Antibody diversity is accounted for by three main theories: (1) the Germ Line Theory, which holds that each antibody-producing cell has genes coding for all possible antibody specificities, but expresses only the one stimulated by antigen; (2) the Somatic Mutation Theory, which holds that antibody-producing cells contain only a few genes, which produce antibody diversity by mutation; and (3) the Gene Rearrangement Theory, which holds that antibody diversity is generated by the rearrangement of IMMUNOGLOBULIN VARIABLE REGION gene segments during the differentiation of the ANTIBODY-PRODUCING CELLS.Thymus Gland: A single, unpaired primary lymphoid organ situated in the MEDIASTINUM, extending superiorly into the neck to the lower edge of the THYROID GLAND and inferiorly to the fourth costal cartilage. It is necessary for normal development of immunologic function early in life. By puberty, it begins to involute and much of the tissue is replaced by fat.Tumor Cells, Cultured: Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely.Peptide Fragments: Partial proteins formed by partial hydrolysis of complete proteins or generated through PROTEIN ENGINEERING techniques.Phospholipase C gamma: A phosphoinositide phospholipase C subtype that is primarily regulated by PROTEIN-TYROSINE KINASES. It is structurally related to PHOSPHOLIPASE C DELTA with the addition of SRC HOMOLOGY DOMAINS and pleckstrin homology domains located between two halves of the CATALYTIC DOMAIN.Transfection: The uptake of naked or purified DNA by CELLS, usually meaning the process as it occurs in eukaryotic cells. It is analogous to bacterial transformation (TRANSFORMATION, BACTERIAL) and both are routinely employed in GENE TRANSFER TECHNIQUES.Genes, Immunoglobulin: Genes encoding the different subunits of the IMMUNOGLOBULINS, for example the IMMUNOGLOBULIN LIGHT CHAIN GENES and the IMMUNOGLOBULIN HEAVY CHAIN GENES. The heavy and light immunoglobulin genes are present as gene segments in the germline cells. The completed genes are created when the segments are shuffled and assembled (B-LYMPHOCYTE GENE REARRANGEMENT) during B-LYMPHOCYTE maturation. The gene segments of the human light and heavy chain germline genes are symbolized V (variable), J (joining) and C (constant). The heavy chain germline genes have an additional segment D (diversity).Lupus Erythematosus, Systemic: A chronic, relapsing, inflammatory, and often febrile multisystemic disorder of connective tissue, characterized principally by involvement of the skin, joints, kidneys, and serosal membranes. It is of unknown etiology, but is thought to represent a failure of the regulatory mechanisms of the autoimmune system. The disease is marked by a wide range of system dysfunctions, an elevated erythrocyte sedimentation rate, and the formation of LE cells in the blood or bone marrow.Antigen Presentation: The process by which antigen is presented to lymphocytes in a form they can recognize. This is performed by antigen presenting cells (APCs). Some antigens require processing before they can be recognized. Antigen processing consists of ingestion and partial digestion of the antigen by the APC, followed by presentation of fragments on the cell surface. (From Rosen et al., Dictionary of Immunology, 1989)Lectins: Proteins that share the common characteristic of binding to carbohydrates. Some ANTIBODIES and carbohydrate-metabolizing proteins (ENZYMES) also bind to carbohydrates, however they are not considered lectins. PLANT LECTINS are carbohydrate-binding proteins that have been primarily identified by their hemagglutinating activity (HEMAGGLUTININS). However, a variety of lectins occur in animal species where they serve diverse array of functions through specific carbohydrate recognition.Intracellular Signaling Peptides and Proteins: Proteins and peptides that are involved in SIGNAL TRANSDUCTION within the cell. Included here are peptides and proteins that regulate the activity of TRANSCRIPTION FACTORS and cellular processes in response to signals from CELL SURFACE RECEPTORS. Intracellular signaling peptide and proteins may be part of an enzymatic signaling cascade or act through binding to and modifying the action of other signaling factors.DNA-Binding Proteins: Proteins which bind to DNA. The family includes proteins which bind to both double- and single-stranded DNA and also includes specific DNA binding proteins in serum which can be used as markers for malignant diseases.Kinetics: The rate dynamics in chemical or physical systems.CD4-Positive T-Lymphocytes: A critical subpopulation of T-lymphocytes involved in the induction of most immunological functions. The HIV virus has selective tropism for the T4 cell which expresses the CD4 phenotypic marker, a receptor for HIV. In fact, the key element in the profound immunosuppression seen in HIV infection is the depletion of this subset of T-lymphocytes.Adaptor Proteins, Signal Transducing: A broad category of carrier proteins that play a role in SIGNAL TRANSDUCTION. They generally contain several modular domains, each of which having its own binding activity, and act by forming complexes with other intracellular-signaling molecules. Signal-transducing adaptor proteins lack enzyme activity, however their activity can be modulated by other signal-transducing enzymesChickens: Common name for the species Gallus gallus, the domestic fowl, in the family Phasianidae, order GALLIFORMES. It is descended from the red jungle fowl of SOUTHEAST ASIA.Gene Expression Regulation: Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control (induction or repression) of gene action at the level of transcription or translation.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Carrier Proteins: Transport proteins that carry specific substances in the blood or across cell membranes.Antigen-Antibody Reactions: The processes triggered by interactions of ANTIBODIES with their ANTIGENS.Myelin-Associated Glycoprotein: A myelin protein found in the periaxonal membrane of both the central and peripheral nervous systems myelin sheaths. It binds to cells surface receptors found on AXONS and may regulate cellular interactions between MYELIN and AXONS.CD40 Ligand: A membrane glycoprotein and differentiation antigen expressed on the surface of T-cells that binds to CD40 ANTIGENS on B-LYMPHOCYTES and induces their proliferation. Mutation of the gene for CD40 ligand is a cause of HYPER-IGM IMMUNODEFICIENCY SYNDROME, TYPE 1.Complementarity Determining Regions: Three regions (CDR1; CDR2 and CDR3) of amino acid sequence in the IMMUNOGLOBULIN VARIABLE REGION that are highly divergent. Together the CDRs from the light and heavy immunoglobulin chains form a surface that is complementary to the antigen. These regions are also present in other members of the immunoglobulin superfamily, for example, T-cell receptors (RECEPTORS, ANTIGEN, T-CELL).Receptor Aggregation: Chemically stimulated aggregation of cell surface receptors, which potentiates the action of the effector cell.Cloning, Molecular: The insertion of recombinant DNA molecules from prokaryotic and/or eukaryotic sources into a replicating vehicle, such as a plasmid or virus vector, and the introduction of the resultant hybrid molecules into recipient cells without altering the viability of those cells.Somatic Hypermutation, Immunoglobulin: A programmed mutation process whereby changes are introduced to the nucleotide sequence of immunoglobulin gene DNA during development.OrosomucoidTyrosine: A non-essential amino acid. In animals it is synthesized from PHENYLALANINE. It is also the precursor of EPINEPHRINE; THYROID HORMONES; and melanin.Receptors, Antigen, T-Cell, gamma-delta: T-cell receptors composed of CD3-associated gamma and delta polypeptide chains and expressed primarily in CD4-/CD8- T-cells. The receptors appear to be preferentially located in epithelial sites and probably play a role in the recognition of bacterial antigens. The T-cell receptor gamma/delta chains are separate and not related to the gamma and delta chains which are subunits of CD3 (see ANTIGENS, CD3).Autoimmune Diseases: Disorders that are characterized by the production of antibodies that react with host tissues or immune effector cells that are autoreactive to endogenous peptides.Gene Rearrangement, B-Lymphocyte, Heavy Chain: Ordered rearrangement of B-lymphocyte variable gene regions of the IMMUNOGLOBULIN HEAVY CHAINS, thereby contributing to antibody diversity. It occurs during the first stage of differentiation of the IMMATURE B-LYMPHOCYTES.Immunoblotting: Immunologic method used for detecting or quantifying immunoreactive substances. The substance is identified by first immobilizing it by blotting onto a membrane and then tagging it with labeled antibodies.Platelet Membrane Glycoproteins: Surface glycoproteins on platelets which have a key role in hemostasis and thrombosis such as platelet adhesion and aggregation. Many of these are receptors.Antigens, Viral: Substances elaborated by viruses that have antigenic activity.src-Family Kinases: A PROTEIN-TYROSINE KINASE family that was originally identified by homology to the Rous sarcoma virus ONCOGENE PROTEIN PP60(V-SRC). They interact with a variety of cell-surface receptors and participate in intracellular signal transduction pathways. Oncogenic forms of src-family kinases can occur through altered regulation or expression of the endogenous protein and by virally encoded src (v-src) genes.Rabbits: The species Oryctolagus cuniculus, in the family Leporidae, order LAGOMORPHA. Rabbits are born in burrows, furless, and with eyes and ears closed. In contrast with HARES, rabbits have 22 chromosome pairs.Mice, Inbred CBAHistocompatibility Antigens Class II: Large, transmembrane, non-covalently linked glycoproteins (alpha and beta). Both chains can be polymorphic although there is more structural variation in the beta chains. The class II antigens in humans are called HLA-D ANTIGENS and are coded by a gene on chromosome 6. In mice, two genes named IA and IE on chromosome 17 code for the H-2 antigens. The antigens are found on B-lymphocytes, macrophages, epidermal cells, and sperm and are thought to mediate the competence of and cellular cooperation in the immune response. The term IA antigens used to refer only to the proteins encoded by the IA genes in the mouse, but is now used as a generic term for any class II histocompatibility antigen.Immunoglobulin lambda-Chains: One of the types of light chain subunits of the immunoglobulins with a molecular weight of approximately 22 kDa.Immunophenotyping: Process of classifying cells of the immune system based on structural and functional differences. The process is commonly used to analyze and sort T-lymphocytes into subsets based on CD antigens by the technique of flow cytometry.Immunization: Deliberate stimulation of the host's immune response. ACTIVE IMMUNIZATION involves administration of ANTIGENS or IMMUNOLOGIC ADJUVANTS. PASSIVE IMMUNIZATION involves administration of IMMUNE SERA or LYMPHOCYTES or their extracts (e.g., transfer factor, immune RNA) or transplantation of immunocompetent cell producing tissue (thymus or bone marrow).Viral Proteins: Proteins found in any species of virus.Antigens, CD4: 55-kDa antigens found on HELPER-INDUCER T-LYMPHOCYTES and on a variety of other immune cell types. CD4 antigens are members of the immunoglobulin supergene family and are implicated as associative recognition elements in MAJOR HISTOCOMPATIBILITY COMPLEX class II-restricted immune responses. On T-lymphocytes they define the helper/inducer subset. CD4 antigens also serve as INTERLEUKIN-15 receptors and bind to the HIV receptors, binding directly to the HIV ENVELOPE PROTEIN GP120.DNA Primers: Short sequences (generally about 10 base pairs) of DNA that are complementary to sequences of messenger RNA and allow reverse transcriptases to start copying the adjacent sequences of mRNA. Primers are used extensively in genetic and molecular biology techniques.Down-Regulation: A negative regulatory effect on physiological processes at the molecular, cellular, or systemic level. At the molecular level, the major regulatory sites include membrane receptors, genes (GENE EXPRESSION REGULATION), mRNAs (RNA, MESSENGER), and proteins.Epitope Mapping: Methods used for studying the interactions of antibodies with specific regions of protein antigens. Important applications of epitope mapping are found within the area of immunochemistry.Immune Sera: Serum that contains antibodies. It is obtained from an animal that has been immunized either by ANTIGEN injection or infection with microorganisms containing the antigen.Immune Tolerance: The specific failure of a normally responsive individual to make an immune response to a known antigen. It results from previous contact with the antigen by an immunologically immature individual (fetus or neonate) or by an adult exposed to extreme high-dose or low-dose antigen, or by exposure to radiation, antimetabolites, antilymphocytic serum, etc.Antibodies, Fungal: Immunoglobulins produced in a response to FUNGAL ANTIGENS.Immunoglobulin A: Represents 15-20% of the human serum immunoglobulins, mostly as the 4-chain polymer in humans or dimer in other mammals. Secretory IgA (IMMUNOGLOBULIN A, SECRETORY) is the main immunoglobulin in secretions.Mice, Mutant Strains: Mice bearing mutant genes which are phenotypically expressed in the animals.Clonal Anergy: Functional inactivation of T- or B-lymphocytes rendering them incapable of eliciting an immune response to antigen. This occurs through different mechanisms in the two kinds of lymphocytes and can contribute to SELF TOLERANCE.Clonal Deletion: Removal, via CELL DEATH, of immature lymphocytes that interact with antigens during maturation. For T-lymphocytes this occurs in the thymus and ensures that mature T-lymphocytes are self tolerant. B-lymphocytes may also undergo clonal deletion.Gene Expression: The phenotypic manifestation of a gene or genes by the processes of GENETIC TRANSCRIPTION and GENETIC TRANSLATION.Binding, Competitive: The interaction of two or more substrates or ligands with the same binding site. The displacement of one by the other is used in quantitative and selective affinity measurements.Antibodies, Blocking: Antibodies that inhibit the reaction between ANTIGEN and other antibodies or sensitized T-LYMPHOCYTES (e.g., antibodies of the IMMUNOGLOBULIN G class that compete with IGE antibodies for antigen, thereby blocking an allergic response). Blocking antibodies that bind tumors and prevent destruction of tumor cells by CYTOTOXIC T-LYMPHOCYTES have also been called enhancing antibodies. (Rosen et al., Dictionary of Immunology, 1989)DNA: A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine).Protein Conformation: The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Cell SeparationAntigens, Differentiation, T-Lymphocyte: Antigens expressed on the cell membrane of T-lymphocytes during differentiation, activation, and normal and neoplastic transformation. Their phenotypic characterization is important in differential diagnosis and studies of thymic ontogeny and T-cell function.Calcium: A basic element found in nearly all organized tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.Sequence Homology, Amino Acid: The degree of similarity between sequences of amino acids. This information is useful for the analyzing genetic relatedness of proteins and species.Models, Molecular: Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.Time Factors: Elements of limited time intervals, contributing to particular results or situations.Antigens, CD8: Differentiation antigens found on thymocytes and on cytotoxic and suppressor T-lymphocytes. CD8 antigens are members of the immunoglobulin supergene family and are associative recognition elements in MHC (Major Histocompatibility Complex) Class I-restricted interactions.Gene Rearrangement, T-Lymphocyte: Ordered rearrangement of T-cell variable gene regions coding for the antigen receptors.Cell Adhesion Molecules: Surface ligands, usually glycoproteins, that mediate cell-to-cell adhesion. Their functions include the assembly and interconnection of various vertebrate systems, as well as maintenance of tissue integration, wound healing, morphogenic movements, cellular migrations, and metastasis.Lymphopenia: Reduction in the number of lymphocytes.Platelet Glycoprotein GPIIb-IIIa Complex: Platelet membrane glycoprotein complex important for platelet adhesion and aggregation. It is an integrin complex containing INTEGRIN ALPHAIIB and INTEGRIN BETA3 which recognizes the arginine-glycine-aspartic acid (RGD) sequence present on several adhesive proteins. As such, it is a receptor for FIBRINOGEN; VON WILLEBRAND FACTOR; FIBRONECTIN; VITRONECTIN; and THROMBOSPONDINS. A deficiency of GPIIb-IIIa results in GLANZMANN THROMBASTHENIA.Receptors, Natural Killer Cell: Receptors that are specifically found on the surface of NATURAL KILLER CELLS. They play an important role in regulating the cellular component of INNATE IMMUNITY.Mice, Inbred Strains: Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations, or by parent x offspring matings carried out with certain restrictions. All animals within an inbred strain trace back to a common ancestor in the twentieth generation.T-Lymphocyte Subsets: A classification of T-lymphocytes, especially into helper/inducer, suppressor/effector, and cytotoxic subsets, based on structurally or functionally different populations of cells.Receptors, Fc: Molecules found on the surface of some, but not all, B-lymphocytes, T-lymphocytes, and macrophages, which recognize and combine with the Fc (crystallizable) portion of immunoglobulin molecules.Jurkat Cells: A CELL LINE derived from human T-CELL LEUKEMIA and used to determine the mechanism of differential susceptibility to anti-cancer drugs and radiation.Membrane Microdomains: Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Polymerase Chain Reaction: In vitro method for producing large amounts of specific DNA or RNA fragments of defined length and sequence from small amounts of short oligonucleotide flanking sequences (primers). The essential steps include thermal denaturation of the double-stranded target molecules, annealing of the primers to their complementary sequences, and extension of the annealed primers by enzymatic synthesis with DNA polymerase. The reaction is efficient, specific, and extremely sensitive. Uses for the reaction include disease diagnosis, detection of difficult-to-isolate pathogens, mutation analysis, genetic testing, DNA sequencing, and analyzing evolutionary relationships.Reverse Transcriptase Polymerase Chain Reaction: A variation of the PCR technique in which cDNA is made from RNA via reverse transcription. The resultant cDNA is then amplified using standard PCR protocols.Cell Division: The fission of a CELL. It includes CYTOKINESIS, when the CYTOPLASM of a cell is divided, and CELL NUCLEUS DIVISION.Receptor-CD3 Complex, Antigen, T-Cell: Molecule composed of the non-covalent association of the T-cell antigen receptor (RECEPTORS, ANTIGEN, T-CELL) with the CD3 complex (ANTIGENS, CD3). This association is required for the surface expression and function of both components. The molecule consists of up to seven chains: either the alpha/beta or gamma/delta chains of the T-cell receptor, and four or five chains in the CD3 complex.PhosphoproteinsImmunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Enzyme Activation: Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.Genes, T-Cell Receptor beta: DNA sequences encoding the beta chain of the T-cell receptor. The genomic organization of the TcR beta genes is essentially the same in all species and is similar to the organization of Ig genes.B-Cell-Specific Activator Protein: A transcription factor that is essential for CELL DIFFERENTIATION of B-LYMPHOCYTES. It functions both as a transcriptional activator and repressor to mediate B-cell commitment.Antibodies, Bispecific: Antibodies, often monoclonal, in which the two antigen-binding sites are specific for separate ANTIGENIC DETERMINANTS. They are artificial antibodies produced by chemical crosslinking, fusion of HYBRIDOMA cells, or by molecular genetic techniques. They function as the main mediators of targeted cellular cytotoxicity and have been shown to be efficient in the targeting of drugs, toxins, radiolabeled haptens, and effector cells to diseased tissue, primarily tumors.Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.Cell Line, Tumor: A cell line derived from cultured tumor cells.Phenylacetates: Derivatives of phenylacetic acid. Included under this heading are a variety of acid forms, salts, esters, and amides that contain the benzeneacetic acid structure. Note that this class of compounds should not be confused with derivatives of phenyl acetate, which contain the PHENOL ester of ACETIC ACID.Enzyme Precursors: Physiologically inactive substances that can be converted to active enzymes.Cell Proliferation: All of the processes involved in increasing CELL NUMBER including CELL DIVISION.Antigens, Neoplasm: Proteins, glycoprotein, or lipoprotein moieties on surfaces of tumor cells that are usually identified by monoclonal antibodies. Many of these are of either embryonic or viral origin.Single-Chain Antibodies: A form of antibodies consisting only of the variable regions of the heavy and light chains (FV FRAGMENTS), connected by a small linker peptide. They are less immunogenic than complete immunoglobulin and thus have potential therapeutic use.HIV Envelope Protein gp120: External envelope protein of the human immunodeficiency virus which is encoded by the HIV env gene. It has a molecular weight of 120 kDa and contains numerous glycosylation sites. Gp120 binds to cells expressing CD4 cell-surface antigens, most notably T4-lymphocytes and monocytes/macrophages. Gp120 has been shown to interfere with the normal function of CD4 and is at least partly responsible for the cytopathic effect of HIV.Antibodies, Antiphospholipid: Autoantibodies directed against phospholipids. These antibodies are characteristically found in patients with systemic lupus erythematosus (LUPUS ERYTHEMATOSUS, SYSTEMIC;), ANTIPHOSPHOLIPID SYNDROME; related autoimmune diseases, some non-autoimmune diseases, and also in healthy individuals.Receptors, Cell Surface: Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.Lymphocyte Cooperation: T-cell enhancement of the B-cell response to thymic-dependent antigens.Immunoglobulin Class Switching: Gene rearrangement of the B-lymphocyte which results in a substitution in the type of heavy-chain constant region that is expressed. This allows the effector response to change while the antigen binding specificity (variable region) remains the same. The majority of class switching occurs by a DNA recombination event but it also can take place at the level of RNA processing.
"Ubiquitous cell-surface glycoprotein on tumor cells is proliferation-associated receptor for transferrin". Proc. Natl. Acad. ... InatherYs, in Évry, France, developed a candidate drug, INA01 antibody (anti-CD71) that showed efficacy in pre-clinical studies ... Each monomer binds one holo-transferrin molecule creating an iron-Tf-TfR complex which enters the cell by endocytosis. TfR1 as ... TfR1 is required for iron import from transferrin into cells by endocytosis. TfR1 is a transmembrane glycoprotein composed of ...
Once interferon has bound to its receptors on the neighboring cell, the signaling proteins STAT1 and STAT2 are activated and ... and difficulty returning to pre-illness weight. Problems with vision may develop. Additionally, survivors develop antibodies ... The Ebolavirus structural glycoprotein (known as GP1,2) is responsible for the virus' ability to bind to and infect targeted ... Once infected, endothelial cells (cells lining the inside of blood vessels), liver cells, and several types of immune cells ...
In the activated state, integrins bind tightly to complementary receptors expressed on endothelial cells, with high affinity. ... presenting pre-formed P-selectins on the endothelial cell surface. P-selectins bind PSGL-1 as a ligand.[4] ... Endothelial selectins bind carbohydrates on leukocyte transmembrane glycoproteins, including sialyl-LewisX. ... Functions include phagocytosis of foreign particles, production of antibodies, secretion of inflammatory response triggers ( ...
Anti-CD9 monoclonal antibody induce pre-B cell adhesion to bone marrow fibroblasts through de novo recognition of fibronectin ... binding of diphtheria toxin to cells revealed the association of a 27-kDa membrane protein with the diphtheria toxin receptor ... CD9 is a cell surface glycoprotein that is known to complex with integrins and other transmembrane 4 superfamily proteins. CD9 ... recognized by monoclonal antibody M31-15, which inhibits cell motility". J. Exp. Med. 174 (6): 1347-1354. doi:10.1084/jem.174.6 ...
Gp120 binds to a CD4 and a co-receptor (CCR5 or CXCR4), found on susceptible cells such as Helper T cells and macrophages. As a ... fusion inhibitor drug that binds to the pre-hairpin structure and prevents membrane fusion and HIV-1 entry to the cell. The ... "Subunit organization of the membrane-bound HIV-1 envelope glycoprotein trimer". Nature Structural & Molecular Biology. 19 (9): ... and it cannot be reached by antibodies then). In addition to antigen binding regions on MPER kinks, there are other targets ...
Recent work has shown that TN-C inhibits HIV infection in immune cells by binding to a chemokine coreceptor site on the HIV-1 ... pre-mRNA splicing patterns and localization of the epitopes recognized by two monoclonal antibodies". Nucleic Acids Res. 19 (3 ... TN-C also interacts with one or more TN-C receptors on cells which activate and repress the same signal transduction pathway. ... Tenascin C (TN-C) is a glycoprotein that in humans is encoded by the TNC gene. It is expressed in the extracellular matrix of ...
"British Journal of Cancer - Abstract of article: HGS-ETR1, a fully human TRAIL-receptor 1 monoclonal antibody, induces cell ... which is a cell surface glycoprotein present on normal mesothelial cells that is over-expressed in numerous cancers including ... In Aptein's technology, stop codons are eliminated so that the completed antibody and its mRNA remain bound together on the ... Scripps and Stratagene and their pre-existing licensees. 'McCafferty' covers the process by which human antibodies are ...
Insertion into blood chemical or organic compounds which binds to the receptors of the CD4 cells. Biological, chemical or ... who found a way to attach HIV-fighting antibodies to immune cells, creating a HIV-resistant cell population. On July 16, 2012, ... Damaging the Docking Glycoprotein gp120 (Phase I-III, VI, VII) Damaging the Transmembrane Glycoprotein gp41 (Phase I-III, VI, ... "Design and Pre-Clinical Evaluation of a Universal HIV-1 Vaccine". PLoS ONE. 2 (10): e984. doi:10.1371/journal.pone.0000984. PMC ...
... forms a dimer associated with membrane-bound immunoglobulin in B-cells, thus forming the B-cell antigen receptor (BCR). This ... CD79A also known as B-cell antigen receptor complex-associated protein alpha chain and MB-1 membrane glycoprotein, is a protein ... However, the presence of both the CD79a and CD79b ITAM tyrosines were required for normal T cell dependent antibody responses. ... exon of CD79A results in loss of CD79a protein and a complete block of B cell development at the pro to pre B cell transition. ...
... it becomes relevant to assess the cell-lines and culture media to "humanise" the glycoprotein to improve performance and yield ... increasing half-life and reducing immunogenicity by reducing the formation of antibodies to the therapeutic glycoprotein When ... There is now substantial pre-clinical evident correlating with human kidney biopsy samples, that some patients with MCD, FSGS ... Weiss, P; Ashwell, G (1989). "The asialoglycoprotein receptor: properties and modulation by ligand". Progress in Clinical and ...
T cells that bind (via their T cell receptor) to self antigen (presented by dendritic cells on MHC molecules) too strongly are ... These peptides are then bound to the cell's major histocompatibility complex (MHC) glycoproteins, which carry the peptides back ... They derive from monocytes, granulocyte stem cells, or the cell division of pre-existing macrophages. Human macrophages are ... Opsonin receptors increase the phagocytosis of bacteria that have been coated with immunoglobulin G (IgG) antibodies or with ...
B cells express a unique B cell receptor (BCR), in this case, a membrane-bound antibody molecule. All the BCR of any one clone ... Lymphoid cells can be identified in some pre-vertebrate deuterostomes (i.e., sea urchins). These bind antigen with pattern ... A more modern explanation for this induction of tolerance is that specific glycoproteins expressed in the uterus during ... known as a plasma cell. Plasma cells are short-lived cells (2-3 days) that secrete antibodies. These antibodies bind to ...
Glycoproteins on the outer surface of the sperm then bind with glycoproteins on the zona pellucida of the ovum. Sperm that did ... If bound to a fluorescent molecule, regions where these probes have bound can be visualised. Sperm cells with artificially ... The antibodies/lectins have a high specificity for different parts of the acrosomal region, and will only bind to a specific ... It also alters a patch of pre-existing sperm plasma membrane so that it can fuse with the egg plasma membrane. A sperm ...
IgA/antigen complex can bind to the Fc receptor of the eosinophil and thereby induce the release of anti-inflammatory mediators ... Kanobana, K.; Koets, A.; Kooyman, F. N. J.; Bakker, N.; Ploeger, H. W.; Vervelde, L. (2003-11-01). "B cells and antibody ... One example is ATP-binding cassette (ABC) transporter families. P-glycoproteins (PGPs) are part of this family and substrates ... The pre-patent period, which includes the time between infection and egg laying, lasts between two and three weeks. Like other ...
... (ENG) is a type I membrane glycoprotein located on cell surfaces and is part of the TGF beta receptor complex. It is ... the crystal structure of endoglin shows that the epitope of anti-ENG monoclonal antibody TRC105 overlaps with the binding site ... Luft FC (Nov 2006). "Soluble endoglin (sEng) joins the soluble fms-like tyrosine kinase (sFlt) receptor as a pre-eclampsia ... region 437-558 in the extracellular domain of endoglin will bind to TGF beta receptor II. TGF beta receptor I binds to the 437- ...
Immunity against zonae pellucidae causes an animal to produce antibodies that themselves are bound by a zona pellucida. Thus ... "Colinear synthesis of an antigen-specific B-cell epitope with a promiscuous tetanus toxin T-cell epitope: a synthetic peptide ... It has been approved by the Indian National Review Committee on Genetic Manipulation and is being produced for pre-clinical ... The zona pellucida is a glycoprotein membrane surrounding the plasma membrane of an ovum. The zona pellucida's main function in ...
It binds to molecules on the surface of cells called receptors and drives the entry of the virus into the cell. VP4 has to be ... Rotaviruses elicit both B and T cell immune responses. Antibodies to the rotavirus VP4 and VP7 proteins neutralise viral ... VP7 is a glycoprotein that forms the outer surface of the virion. Apart from its structural functions, it determines the G-type ... In the pre-vaccination era, rotavirus infections occurred primarily during cool, dry seasons. The number attributable to food ...
Their binding ensures correct placement of prolactin receptors on the basal lateral side of alveoli cells and directional ... Complex glycoproteins such as monoclonal antibodies or antithrombin cannot be produced by genetically engineered bacteria, and ... First development is frequently seen during pre- and postnatal stages, and later during puberty. Estrogen promotes branching ... with strong adhesion to epithelial cells via binding to integrin and non-integrin receptors. When side branches develop, it is ...
... an antigenic glycoprotein found on the surface of the influenza viruses and is responsible for binding the virus to the cell ... The avian influenza hemagglutinin binds alpha 2-3 sialic acid receptors, while human influenza hemagglutinins bind alpha 2-6 ... "Antigenic and genetic characteristics of H5N1 viruses and candidate H5N1 vaccine viruses developed for potential use as pre- ... RNA strands specify the structure of proteins that are most medically relevant as targets for antiviral drugs and antibodies. ...
... antibodies - antibody-dependent cell-mediated cytotoxicity (ADCC) - antibody-mediated immunity - antifungal medication - ... pre-conception counseling - preclinical - precursor cells - prevalence - primary HIV infection - primary isolate - primaquine ... binding antibody - bioavailability - biological response modifiers (BRMs) - biopsy - biotechnology - blinded study - blips - ... glycoprotein - gonorrhea - gp120 (gp120) - gp160 (gp160) - gp41 (gp41) - granulocyte - granulocyte macrophage-colony ...
... and is found on professional APCs and T-cells. Macrophage scavenger receptors bind to a variety of macromolecules, including ... lymphoid tissues in the initiation and maintenance of DNA-raised antibody responses to the influenza virus H1 glycoprotein". J ... These models, while not ideal for extrapolation to P. falciparum in humans, will be important in pre-clinical trials. The ... These might include a 30kDa surface receptor, or macrophage scavenger receptors. The 30kDa surface receptor binds specifically ...
Thymocyte B cell development Pre-pro-B cell Early pro-B cell Late pro-B cell Large pre-B cell Small pre-B cell Immature B cell ... Homodimer upon ligand binding GHR (Growth hormone receptor) - Homodimer upon ligand binding PRLR (Prolactin receptor) Type II ... Antibodies Kinds of Antibodies Monoclonal antibodies Polyclonal antibodies Autoantibody Microantibody Neutralizing antibody ... Dimers Cytoadhesin receptor Integrin alpha6beta4 Glycoprotein IIb/IIIa - Heterodimer: ITGA2B / ITGB3 Fibrinogen receptor ...
... by binding to the cell surface receptors VEGFr1 and VEGFr2, two tyrosine kinases located in endothelial cells of the ... Vascular endothelial growth factor A (VEGF-A) is a dimeric glycoprotein that plays a significant role in neurons and is ... VEGF-A mediates the growth of new blood vessels from pre-existing vessels (angiogenesis) ... anti VEGF-A human antibody drug. GRCh38: Ensembl release 89: ENSG00000112715 - Ensembl, May 2017 GRCm38: Ensembl release 89: ...
It is mediated by the binding of XNAs (xenoreactive natural antibodies) to the donor endothelium, causing activation of the ... Xenotransplantation of human tumor cells into immunocompromised mice is a research technique frequently used in pre-clinical ... In pig to primate xenotransplantation, XNAs recognize porcine glycoproteins of the integrin family. The binding of XNAs ... soluble complement receptor type 1, anti-C5 antibodies, or C1 inhibitor (C1-INH). Disadvantages of this approach include the ...
... GP1b-IX-V receptor binds with VWF; and GPVI receptor and integrin α2β1 bind with collagen.[19] ... Berridge, Michael J. (1 October 2014). "Module 11: Cell Stress, Inflammatory Responses and Cell Death". Cell Signalling Biology ... Platelets are activated by collagen receptor glycoprotein IV (GPVI). Proinflammatory platelet microvesicles trigger constant ... Activated platelets are able to participate in adaptive immunity, interacting with antibodies. They are able to specifically ...
... molecule, immunoglobulin-associated beta, also known as CD79B (Cluster of Differentiation 79B), is a human gene. It is associated with agammaglobulinemia-6. The B lymphocyte antigen receptor is a multimeric complex that includes the antigen-specific component, surface immunoglobulin (Ig). Surface Ig non-covalently associates with two other proteins, Ig-alpha and Ig-beta, which are necessary for expression and function of the B-cell antigen receptor. This gene encodes the Ig-beta protein of the B-cell antigen component. Alternatively spliced transcript variants encoding different isoforms have been described. Cluster of differentiation GRCh38: Ensembl release 89: ENSG00000007312 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000040592 - Ensembl, May 2017 "Human PubMed Reference:". "Mouse PubMed Reference:". "Entrez Gene: CD79B CD79b molecule, immunoglobulin-associated beta". Reth M (1992). "Antigen ...
Epstein-Barr virus (EBV) latent membrane protein 2 (LMP2) are two viral proteins of the Epstein-Barr virus. LMP2A/LMP2B are transmembrane proteins that act to block tyrosine kinase signaling. LMP2A is a transmembrane protein that inhibits normal B-cell signal transduction by mimicking an activated B-cell receptor (BCR). The N-terminus domain of LMP2A is tyrosine phosphorylated and associates with Src family protein tyrosine kinases (PTKs) as well as spleen tyrosine kinase (Syk). PTKs and Syk are associated with BCR signal transduction. Latent Membrane Protein 2 (LMP2) is a rightward transcribing gene. LMP2's transcript originates across the fused terminal repeats in sequences at opposite ends of the genome. 16‍-‍24 hours after infection, the genome circularizes and the open reading frame is created. 1.7 kb and 2.0 kb messages are created by alternative promoter usage and differ only in the sequences of the first exon. These messages are ...
Cluster of differentiation CD79A also known as B-cell antigen receptor complex-associated protein alpha chain and MB-1 membrane glycoprotein, is a protein that in humans is encoded by the CD79A gene. The CD79a protein together with the related CD79b protein, forms a dimer associated with membrane-bound immunoglobulin in B-cells, thus forming the B-cell antigen receptor (BCR). This occurs in a similar manner to the association of CD3 with the T-cell receptor, and enables the cell to respond to the presence of antigens on its surface. It is associated with agammaglobulinemia-3. The mouse CD79A gene, then called mb-1, was cloned in the late 1980s, followed by the discovery of human CD79A in the early 1990s. It is a short gene, 4.3 kb in length, with 5 exons encoding for 2 splice variants resulting in 2 ...
... (XLA) is a rare genetic disorder discovered in 1952 that affects the body's ability to fight infection. As the form of agammaglobulinemia that is X-linked, it is much more common in males. In people with XLA, the white blood cell formation process does not generate mature B cells, which manifests as a complete or near-complete lack of proteins called gamma globulins, including antibodies, in their bloodstream. B cells are part of the immune system and normally manufacture antibodies (also called immunoglobulins), which defend the body from infections by sustaining a humoral immunity response. Patients with untreated XLA are prone to develop serious and even fatal infections. A mutation occurs at the Bruton's tyrosine kinase (Btk) gene that leads to a severe block in B cell development (at the pre-B cell to immature B ...
Signal-transducing adaptor protein 1 is a protein that in humans is encoded by the STAP1 gene. The protein encoded by this gene functions as a docking protein acting downstream of Tec tyrosine kinase in B cell antigen receptor signaling. The protein is directly phosphorylated by Tec in vitro where it participates in a positive feedback loop, increasing Tec activity. A mouse ortholog, stem cell adaptor protein 1, shares 83% identity with its human counterpart. STAP1 has been shown to interact with C19orf2. GRCh38: Ensembl release 89: ENSG00000035720 - Ensembl, May 2017 GRCm38: Ensembl release 89: ENSMUSG00000029254 - Ensembl, May 2017 "Human PubMed Reference:". "Mouse PubMed Reference:". Ohya K, Kajigaya S, Kitanaka A, Yoshida K, Miyazato A, Yamashita Y, Yamanaka T, Ikeda U, Shimada K, Ozawa K, Mano H (Nov 1999). "Molecular cloning of a docking protein, BRDG1, that acts downstream of the Tec tyrosine kinase". Proc Natl Acad Sci U S A. 96 ...
Ig epsilon chain C region is a protein that in humans is encoded by the IGHE gene. "Human PubMed Reference:". "Entrez Gene: IGHE immunoglobulin heavy constant epsilon". Venkitaraman AR, Williams GT, Dariavach P, Neuberger MS (Aug 1991). "The B-cell antigen receptor of the five immunoglobulin classes". Nature. 352 (6338): 777-81. doi:10.1038/352777a0. PMID 1881434. Padlan EA, Davies DR (Oct 1986). "A model of the Fc of immunoglobulin E". Molecular Immunology. 23 (10): 1063-75. doi:10.1016/0161-5890(86)90005-2. PMID 3796618. Flanagan JG, Rabbitts TH (1984). "The sequence of a human immunoglobulin epsilon heavy chain constant region gene, and evidence for three non-allelic genes". The EMBO Journal. 1 (5): 655-60. PMC 553102 . PMID 6234164. Max EE, Battey J, Ney R, Kirsch IR, Leder P (Jun 1982). "Duplication and deletion in the human immunoglobulin epsilon genes". Cell. 29 (2): 691-9. doi:10.1016/0092-8674(82)90185-4. PMID 6288268. Ellison J, ...
... (also known as TGN1412, CD28-SuperMAB, and TAB08) is an immunomodulatory drug developed by Professor Thomas Hünig of the University of Würzburg. It was withdrawn from development after inducing severe inflammatory reactions in the first-in-man study by PAREXEL in London in March 2006. The developing company, TeGenero Immuno Therapeutics, went bankrupt later that year. The commercial rights were then acquired by a Russian startup, TheraMAB. The drug was renamed TAB08. Phase I and II clinical trials have been completed for arthritis and clinical trials have been initiated for cancer. Originally intended for the treatment of B cell chronic lymphocytic leukemia (B-CLL) and rheumatoid arthritis, TGN1412 is a humanised monoclonal antibody that not only binds to, but is a strong agonist for, the CD28 receptor of the immune system's T cells. CD28 is the co-receptor for the T ...
CD4+ T cells provide help to B cells that produce antibodies. Several subsets of activated effector CD4+ T cells are observed in disease pathology. Earlier studies summarized by Sanders and Lynch in 1993 suggested critical roles for FcRs in CD4+ T cell mediated immune responses and proposed the formation of a joint signaling complex among FcRs and TCR on the cell surface.[37][38][39][40] Chauhan and coworkers reported the colocalization of the labeled ICs with the CD3 complex on activated CD4+ T cell surface, which thus suggest the coexistence of FcRs together with TCR complex.[41] Both of these receptors are observed forming an apical structure on the membrane of activated CD4+ T cells, suggesting the lateral movement of these ...
Francois DT, Katona IM, June CH, et al. (1988). "Examination of the inhibitory and stimulatory effects of IFN-alpha, -beta, and -gamma on human B-cell proliferation induced by various B-cell mitogens". Clin. Immunol. Immunopathol. 48 (3): 297-306. doi:10.1016/0090-1229(88)90023-2. PMID 3135963 ...
An antibody microarray (also known as antibody array) is a specific form of protein microarray. In this technology, a collection of capture antibodies are spotted and fixed on a solid surface such as glass, plastic, membrane, or silicon chip, and the interaction between the antibody and its target antigen is detected. Antibody microarrays are often used for detecting protein expression from various biofluids including serum, plasma and cell or tissue lysates. Antibody arrays may be used for both basic research and medical and diagnostic applications. The concept and methodology of antibody microarrays were first introduced by Tse Wen Chang in 1983 in a scientific publication and a series of patents, when he was working at Centocor in Malvern, Pennsylvania. Chang coined the term "antibody matrix" and discussed "array" arrangement of minute ...
Antibodies (also called immunoglobulins) are large Y-shaped proteins. They are found in the blood or other body fluids of vertebrates. Antibodies are the key element in the adaptive immune system. The antibody recognizes a unique part of the foreign target called an antigen.[1][2] Each tip of the "Y" of an antibody contains a structure (like a lock) that fits one particular key-like structure on an antigen. This binds the two structures together. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly.[3] The production of antibodies is the main function of the humoral immune system.[4][5] Each antibody is different. They are all designed to attack only one kind of antigen (in practice, this means virus or bacteria). For instance, an antibody ...
An antibody (Ab), also known as an immunoglobulin (Ig),[1] is a large, Y-shaped protein produced mainly by plasma cells that is used by the immune system to neutralize pathogens such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the pathogen, called an antigen, via the Fab's variable region.[2][3] Each tip of the "Y" of an antibody contains a paratope (analogous to a lock) that is specific for one particular epitope (similarly analogous to a key) on an antigen, allowing these two structures to bind together with precision. Using this binding mechanism, an antibody can tag a microbe or an infected cell for attack by other parts of the immune system, or can neutralize its target directly (for example, by blocking a part of a microbe that is essential for its invasion and survival). Depending ...
The direct method is a one-step staining method and involves a labeled antibody (e.g. FITC-conjugated antiserum) reacting directly with the antigen in tissue sections. While this technique utilizes only one antibody and therefore is simple and rapid, the sensitivity is lower due to little signal amplification, in contrast to indirect approaches.[4] However, this strategy is used less frequently than its multi-phase counterpart. The indirect method involves an unlabeled primary antibody (first layer) that binds to the target antigen in the tissue and a labeled secondary antibody (second layer) that reacts with the primary antibody. As mentioned above, the secondary antibody must be raised against the IgG of the animal species in which the primary antibody has been raised. This method is more sensitive than direct detection strategies because of signal amplification due to the ...
Siglec-G is expressed on cells of the B cell lineage. Siglec-G is most highly expressed by pre-B cells and B1a cells within the ... The SH1 monoclonal antibody specifically binds to mouse Siglec-G (sialic acid binding immunoglobulin-like lectin G), also known ... B cell lineage and is not detectable on T cells. Siglec-G can inhibit B cell receptor-mediated calcium signaling when it is ... Siglec-G is a Type I transmembrane glycoprotein that belongs to the Immunoglobulin superfamily. Siglec-G functions as an ...
VEGF binds to vascular endothelial cells via specific VEGF receptor on cell surface, and induces cell mitosis, migration, and ... In several clinical trials, addition of VEGF specific monoclonal antibody (Avastin), which can void VEGF function, to pre- ... MDR phenotype in various type of cancer is frequently associated with upregulation of the permeability-glycoprotein (P-gp). P- ... Since DNA aptamers, which has antibody-compatible specific binding ability for several kinds of antigen, has been found out day ...
The identification of a single-CD4 bound asymmetric HIV-1 Envelope trimer intermediate provides new mechanistic insights into ... HIV-1 entry into cells requires binding of the viral envelope glycoprotein (Env) to receptor CD4 and coreceptor. Imaging of ... Antibody potency relates to the ability to recognize the closed, pre-fusion form of HIV Env * M Guttman ... enters CD4+ T cells through the interaction of its envelope glycoprotein (Env) with cell-surface receptor CD4 and coreceptor ...
... epitopes are not fully revealed until the Env glycoprotein spike changes conformation upon receptor and coreceptor binding (22- ... A more likely mechanism for enhanced Ab-mediated neutralization of HIV-1 in TZM-bl/FcγRI cells is that the Fc receptor pre- ... Many cells of the immune system express Fc receptors that bind immune complexes through the constant region of immunoglobulins ... Access of antibody molecules to the conserved coreceptor binding site on glycoprotein gp120 is sterically restricted on primary ...
They work together when they encounter a host cell. GP1 binds to a host cell receptor, and GP2 starts the fusion process to ... She then used this model glycoprotein as a sort of magnet to find antibodies in patient samples that could bind with the ... This "drip" holds the two subunits together in their pre-fusion state. ... At last, she solved the structure of the Lassa virus glycoprotein, bound to a neutralizing antibody from a human survivor. ...
They work together when they encounter a host cell. GP1 binds to a host cell receptor, and GP2 starts the fusion process to ... She then used this model glycoprotein as a sort of magnet to find antibodies in patient samples that could bind with the ... This drip holds the two subunits together in their pre-fusion state. ... Tags: Antibodies, Antibody, Arenavirus, Arthritis, Birth Defects, Cancer, Cell, Crystallography, Diffraction, Ebola Virus, ...
... i in neutrophils that was markedly enhanced by pre?treatmentwith anti?L?selectin antibodies. In contrast, desialylation of AGP ... i in neutrophils through binding to the leukotriene B4 receptor BLT2. Wepropose a two?step binding model where AGP binds to ... Effects of ?1?acid glycoprotein onpolymorphonuclear leukocytes ?involvement of cell surface receptors by Levander, Louise, PhD ... Alpha1?acid glycoprotein (AGP) is a highly glycosylated lipid?binding acute?phaseprotein. Although the exact mechanisms are ...
HA is also the major target for neutralizing antibodies that bind to either prevent receptor binding or membrane fusion. ... The trimeric influenza viral fusion glycoprotein hemagglutinin (HA) binds cell surface sialic acid moieties to trigger ... We also find that while neutralizing antibodies prevent fusion by stabilizing the pre-fusion state, other therapeutic proteins ... The fusion glycoproteins found on the surface of enveloped viruses enable the delivery of the viral genome into the host cell ...
"Ubiquitous cell-surface glycoprotein on tumor cells is proliferation-associated receptor for transferrin". Proc. Natl. Acad. ... InatherYs, in Évry, France, developed a candidate drug, INA01 antibody (anti-CD71) that showed efficacy in pre-clinical studies ... Each monomer binds one holo-transferrin molecule creating an iron-Tf-TfR complex which enters the cell by endocytosis. TfR1 as ... TfR1 is required for iron import from transferrin into cells by endocytosis. TfR1 is a transmembrane glycoprotein composed of ...
Reveals First-Ever Image of Elusive Viral Protein responsible for the machinery that Lassa virus uses to enter human cells. ... GP1 binds to a host cell receptor, and GP2 starts the fusion process to enter that cell. The new structure also showed a long ... At last, she solved the structure of the Lassa virus glycoprotein, bound to a neutralizing antibody from a human survivor. Her ... This "drip" holds the two subunits together in their pre-fusion state. Zooming in even closer, Hastie discovered that three of ...
Description: The OKT4 monoclonal antibody reacts with human CD4, a 59 kDa cell surface glycoprotein expressed by the majority ... CD4 functions to initiate or augment the early phase of T-cell activation through its association with the T-cell receptor ... antibody has been pre-titrated and tested by flow cytometric analysis of normal human peripheral blood cells. This can be used ... and these antibodies do not cross-block binding to each other ft.s respective epitopes. Applications Reported: This OKT4 (OKT-4 ...
Antibody eFluor™ 450 conjugate (19.2) from Invitrogen™. Species Reactivity: Human; Applications: Flow Cytometry ... including hepatic and lymphathic epithelia and kidney mesengial cells. CD206 binds to glycoproteins that terminate in D-mannose ... antibody has been pre-titrated and tested by flow cytometric analysis of GM-CSF-stimulated normal human peripheral blood cells ... Description: This 19.2 monoclonal antibody reacts with human CD206, which is also known as the macrophage mannose receptor (MMR ...
HA plays a key role in virus cell entry by binding to cell surface receptors, which are found also on red blood cells of ... The pre- and post immunization HI antibodies were tested at the Central Virology Laboratory of the Israeli Ministry of Health ... Influenza virus has two important surface glycoproteins: the haemagglutinin (HA) and the neuraminidase (NA). Antigenic ... In the HI test, antibody directed against the viral haemagglutinins block the virus from binding to the blood cells and thus ...
Some of the beneficial effects of fingolimod in EAE and MS could be attributed to SP1 receptor modulation in these cells and ... NgR1 binds myelin-associated inhibitors of axonal regeneration such as Nogo-A, myelin-associated glycoprotein and ... 4 - Krumbholz M, Derfuss T, Hohlfeld R, Meinl E. B cells and antibodies in multiple sclerosis pathogenesis and therapy. Nat Rev ... the protective effect of dimethyl fumarate could depend on pre-existing tissue expression of Nrf2. Actually, Nrf2 is ...
... binding to a receptor(s) on a host cell acts as the first step in a series of events culminating in fusion with the host cell ... reconstructions of B41 SOSIP Env trimers with no ligand or in complex with either CD4 or the CD4-binding-site antibody PGV04 at ... Soluble SOSIP Env trimers are structural and antigenic mimics of the pre-fusion native, surface-presented Env3,4, and are ... membrane and transfer of genetic material for replication1,2. The envelope glycoprotein (Env) trimer on the surface of HIV is ...
This surface glycoprotein is responsible for virus binding to host cell receptors, and subsequent membrane fusion events within ... which contains the host receptor binding site and major epitopes for neutralizing antibodies. Although phylogenetic analyses ... from the 1918 influenza virus1 A/South Carolina/1/18 was cloned and expressed in a baculovirus expression system as the pre- ... Receptor binding site (blue shade) for virus attachment to the host lung epithelial cells via sialic acid containing host cell ...
Daratumumab is an IgG1κ human monoclonal antibody that binds to CD38 and inhibits the growth of CD38-expressing tumor cells by ... The transmembrane glycoprotein CD38 is expressed on the surface of hematopoietic cells, including multiple myeloma and other ... Pre- and postinfusion medication must be given.. The maximum infusion rate for all infusions is 200 mL/h. For first infusion, ... cell types and tissues, and has multiple functions, including receptor-mediated adhesion, signaling, and modulation of cyclase ...
... target the receptor-binding domain (RBD) of the spike glycoprotein and block its binding to the cellular receptor dipeptidyl ... but also acts after viral cell attachment, inhibiting the pre-fusion to post-fusion conformational change of the spike. These ... Efforts to develop antibody-based therapies have focused on neutralizing antibodies that target the receptor binding domain of ... Publications A Cryptic Site of Vulnerability on the Receptor Binding Domain of the SARS-CoV-2 Spike Glycoprotein. M. Gordon ...
... a chimeric Sindbis glycoprotein containing an Fc antibody binding domain targets to Her2/neu overexpressing breast cancer cells ... displaying immunoglobulin-binding domains permit antibody-mediated vector retargeting to specific cell surface receptors. J ... Ohno K, Sawai K, lijima Y, Levin B, Meruelo D (1997) Cell-specific targeting of Sindbis virus vectors displaying IgG-binding ... Morizono K, Bristol G, Xie YM, Kung SKP, Chen ISY (2001) Antibody-directed targeting of retroviral vectors via cell surface ...
Anti-Human CD19, Clone HIB19 is suitable for applications such as cell isolation and flow cytometry. ... CD19 is expressed on the surface of B cells. ... a co-receptor for the B cell receptor and is involved in B cell ... from early pre-B cells to plasma cells. Expression is down-regulated but persists in terminally differentiated plasma cells. ... The HIB19 antibody reacts with CD19, an ~95 kDa type 1 transmembrane glycoprotein expressed on the surface of B cells ...
In bone marrow, CD22 is not detectable on pro-B cells, pre-B cells, and emerging IgM+ B cells. CD22 plays a strong role in cell ... interactions and B cell activation. Additional information: Clone REA1187 displays negligible binding to Fc receptors. - Italia ... Lyb-8.2 is expressed at mature levels on all B cell subsets. ... Clone REA1187 recognizes the 150 kDa B cell-restricted ... glycoprotein CD22 on mice strains having the Lyb-8.2 alloantigen, e.g., A, BALB/c, CBA, C3H/He, C57BL, C57L, C58, SJL, and SWR ...
... researchers from The Scripps Research Institute emerge with a clear picture of how the deadly Lassa virus enters human cells. ... They work together when they encounter a host cell. GP1 binds to a host cell receptor, and GP2 starts the fusion process to ... She then used this model glycoprotein as a sort of magnet to find antibodies in patient samples that could bind with the ... This "drip" holds the two subunits together in their pre-fusion state. ...
This antibody reacts with human samples. Cat.No. 22349-1-AP. ... CD79A antibody Rabbit Polyclonal from Proteintech validated in ... CD79A, also named as B-cell antigen receptor complex-associated protein alpha chain or MB-1 membrane glycoprotein, is a 226 ... with CD79B for initiation of the signal transduction cascade activated by binding of antigen to the B-cell antigen receptor ... CD79A is also required for BCR surface expression and for efficient differentiation of pro- and pre-B-cells. ...
NK cells, α/β− and γ/δ−T cell receptor+ T cells, and U937 (myeloid cell), but not substantially in other tissues or JY (B ... whereas NKG2D directly binds MICA (7, 9). Having separate components of a multisubunit receptor responsible for ligand binding ... Protein immunoblot analysis of the NK cell line NKL, using an affinity-purified antibody to DAP10 (anti-DAP10), revealed ... The mouse pre-B cell line Ba/F3 was transfected with an NH2-terminal Flag-tagged human DAP10 cDNA (Flag-DAP10), either alone or ...
B7-H3, a surface immunomodulatory glycoprotein, inhibits natural killer cells and T cells. The monoclonal antibody (mAb) 8H9 is ... promoted T-cell activation and IFN-γ production by binding to a putative receptor on activated T cells ( 2). Furthermore, ... Mature miRNAs are ∼22 nucleotide (nt) molecules cleaved from ∼70- to 100-nt hairpin pre-miRNA precursors ( 14). Single-stranded ... cell-mediated lysis of neuroblastoma cells by interacting with a putative inhibitory receptor on the surface of NK cells ( 6). ...
  • Imaging of individual Env molecules on native virions shows Env trimers to be dynamic, spontaneously transitioning between three distinct well-populated conformational states: a pre-triggered Env (State 1), a default intermediate (State 2) and a three-CD4-bound conformation (State 3), which can be stabilized by binding of CD4 and coreceptor-surrogate antibody 17b. (elifesciences.org)
  • The trimer can then transition to State 3 by binding additional CD4 molecules and coreceptor. (elifesciences.org)
  • The CD4 antigen is involved in the recognition of MHC class II molecules and is a co-receptor for HIV. (fishersci.com)
  • Mature miRNAs are ∼22 nucleotide (nt) molecules cleaved from ∼70- to 100-nt hairpin pre-miRNA precursors ( 14 ). (aacrjournals.org)
  • CD36 is preferentially found within lipid rafts, which facilitates its association with receptors, signaling and adapter molecules. (thermofisher.com)
  • A principal limitation of cancer immunotherapy is that most solid tumors are poorly antigenic, expression of MHC Class I molecules is very low, no T cells are available that have high avidity for tumor specific antigens, or no T cells that have the desired specificities remain in the patient after chemotherapy. (pnas.org)
  • Using the WM78 monoclonal antibody, which recognizes the common extracellular domain of the PZR isoforms, we demonstrate that the PZR molecules are expressed on mesenchymal and haematopoietic cells, being present on the majority of CD34(+)CD38(+) and early clonogenic progenitors, and at lower levels on CD34(+)CD38(-) cells and the hierarchically more primitive pre-colony forming units. (ox.ac.uk)
  • Unfortunately, drug resistance occurs not only with long-established cytotoxic drugs, but also with the more recent small molecules and therapeutic antibodies, which are directed against specific targets in tumor cells [ 1 ]. (mdpi.com)
  • molecules implicated in the entry of flaviviruses into cells include several lectins (DC-SIGN, DC-SIGNR, and mannose receptor), heparin sulfate, and molecules of the TIM/TAM family. (nih.gov)
  • One feature of the carboxy-terminal domain of Toxin A is the presence of repeating units of amino acids that form a series of binding sites able to recognise disaccharides and trisaccharides on glycolipid and glycoprotein receptor molecules. (gla.ac.uk)
  • CD160 shows a broad specificity for binding to both classical and nonclassical MHC class I molecules. (abnova.com)
  • There is currently considerable interest in developing contrast-ligand probes to enable imaging of specific molecules, cells and processes that are important to atherosclerosis. (herzzentrum.de)
  • The mechanism of action is thought to involve steric hindrance and/or conformational effects to block access of large molecules to the receptor rather than direct interaction with the RGD (arginine-glycine-aspartic acid) binding site of GPIIb/IIIa. (nih.gov)
  • His work has revealed key functional and structural information about T cell receptors (TCRs), the CD3 signaling subunits, and how, with other molecules, TCRs bind to peptide-loaded MHC. (dana-farber.org)
  • In addition, we have derived further detail about CD4 and CD8 coreceptors and their binding to the major histocompatibility complex (MHC) molecules of class II and class I, respectively.Recently, we have shown that agonist mAbs footprint to the membrane distal CD3epsilon lobe which they approach diagonally, adjacent to the lever-like Cbeta FG loop that facilitates antigen (pMHC)-triggered activation. (dana-farber.org)
  • A common TCR quaternary change rather than conformational alterations can better facilitate structural signal initiation, given the vast array of TCRs and their specific pMHC ligands.Using computational methods, we have also defined the rules concerning the nature of peptides that bind to individual human MHC molecules, including multiple allelic variants, and developed bioinformatic approaches to create computational vaccinology. (dana-farber.org)
  • Major Histocompatibility Complex (MHC) class I molecules selectively bind peptides for presentation to cytotoxic T cells. (bvsalud.org)
  • Specificity analyses of peptide binding to human leukocyte antigen (HLA)-A molecules have been hampered due to a lack of proper monoclonal antibodies (mAbs) for certain allomorphs, such as the prevalent HLA-A1 for Caucasians and HLA-A11 for Asians. (bvsalud.org)
  • A stabilization assay using TAP-deficient cell lines and A-1 was developed to investigate the specificity of peptide binding to HLA-A molecules. (bvsalud.org)
  • The available unnatural sugar molecules which are similar to endogenous sugar molecules show minimal perturbation in cell function and - based on their multitude functional groups - offer the potential of side directed coupling with a target substance/structure as well as the development of new biological properties. (uni-wuerzburg.de)
  • Immunogen sequence: V20-P211) and test samples are added to the wells, a biotinylated detection polyclonal antibody from goat specific for TNFRSF4/OX40 is added subsequently and then followed by washing with PBS or TBS buffer. (abcam.com)
  • Abciximab therefore inhibits platelet aggregation by preventing the binding of pro-coagulants such as fibrinogen, von Willebrand factor, and others to the GPIIb/IIIa receptor sites on activated platelets. (clinimmsoc.org)
  • Abciximab also reduces platelet adhesion to other cell types via binding to the vitronectin receptor on platelets as well as endothelial and smooth muscle cells, and via binding to the activated macrophage antigen-1 integrin (Mac-1 receptor) located on granulocytes and monocytes. (clinimmsoc.org)
  • 2. Nurden AT, Poujol C, Durrieu-Jais C, Nurden P. Platelet glycoprotein IIb/IIIa inhibitors: basic and clinical aspects. (clinimmsoc.org)
  • 4. Starnes HB, Patel AA, Stouffer GA. Optimal use of platelet glycoprotein IIb/IIIa receptor antagonists in patients undergoing percutaneous coronary interventions. (clinimmsoc.org)
  • Platelet glycoprotein IIb/IIIa inhibitors reduce mortality in diabetic patients with non-ST-segment-elevation acute coronary syndromes. (clinimmsoc.org)
  • Mutations in the CD36 gene cause platelet glycoprotein deficiency. (thermofisher.com)
  • This indicates that C1q may regulate platelet activation via the GPVI receptor, which is a novel finding. (diva-portal.org)
  • Moreover, C1q antagonized the collagen-induced formation of platelet-neutrophil aggregates, indicating a reduced interaction between platelet P-selectin and neutrophil P-selectin glycoprotein ligand-1(PSGL-1/CD162). (diva-portal.org)
  • Abciximab binds to the glycoprotein (GP) IIb/IIIa receptor of human platelets and inhibits platelet aggregation. (nih.gov)
  • General - Abciximab binds to the intact platelet GPIIb/IIIa receptor, which is a member of the integrin family of adhesion receptors and the major platelet surface receptor involved in platelet aggregation. (nih.gov)
  • 80% GPIIb/IIIa receptor blockade, but above the in vivo therapeutic range, Abciximab more effectively blocked the burst of thrombin generation that followed platelet activation than select comparator antibodies which inhibit GPIIb/IIIa alone (1). (nih.gov)
  • Pre-clinical experience- Maximal inhibition of platelet aggregation was observed when ≥ 80% of GPIIb/IIIa receptors were blocked by Abciximab. (nih.gov)
  • In non-human primates, Abciximab bolus doses of 0.25 mg/kg generally achieved a blockade of at least 80% of platelet receptors and fully inhibited platelet aggregation. (nih.gov)
  • Inhibition of platelet function was temporary following a bolus dose, but receptor blockade could be sustained at ≥ 80% by continuous intravenous infusion. (nih.gov)
  • Pharmacokinetics- Following intravenous bolus administration, free plasma concentrations of Abciximab decrease rapidly with an initial half-life of less than 10 minutes and a second phase half-life of about 30 minutes, probably related to rapid binding to the platelet GPIIb/IIIa receptors. (nih.gov)
  • Platelet function generally recovers over the course of 48 hours (5,6), although Abciximab remains in the circulation for 15 days or more in a platelet-bound state. (nih.gov)
  • Unlike thrombotic thrombocytopenic purpura (TTP), where the main mechanism is repre-sen--ted by autoantibodies directed to ADAMTS13 protease (10) , primary ITP is an acquired immune disorder which is characterized by pathologic platelet antibodies, impaired megakaryocytopoiesis and T-cell mediated destruction of platelets (4,8) . (medichub.ro)
  • Also, it has been discovered that certain changes in T cell population, such as the loss of regulatory T cells and an increase in T-proinflammatory responses, are responsible for low platelet value. (medichub.ro)
  • The accessibility of the highly conserved fusion peptide at the periphery of the trimer indicates potential vaccinology strategies to elicit broadly neutralizing antibodies against coronaviruses. (nanotempertech.com)
  • 1996) Differential expression of CD22 (Lyb8) on murine B cells. (miltenyibiotec.com)
  • 1. Coller BS, Peerschke EI, Scudder LE, Sullivan CA. A murine monoclonal antibody that completely blocks the binding of fibrinogen to platelets produces a thrombasthenic-like state in normal platelets and binds to glycoproteins IIb and/or IIIa. (clinimmsoc.org)
  • Immunofluorescence analyzes of murine CMV infected cells suggest perturbations of Rab cascades that operate at the ERC. (frontiersin.org)
  • Abciximab, ReoPro ® , is the Fab fragment of the chimeric human-murine monoclonal antibody 7E3. (nih.gov)
  • The antithrombotic efficacy of prototype antibodies [murine 7E3 Fab and F(ab´) 2 ] and Abciximab was evaluated in dog, monkey and baboon models of coronary, carotid, and femoral artery thrombosis. (nih.gov)
  • Doses of the murine version of 7E3 or Abciximab sufficient to produce high-grade (≥ 80%) GPIIb/IIIa receptor blockade prevented acute thrombosis and yielded lower rates of thrombosis compared with aspirin and/or heparin. (nih.gov)
  • Antibody humanization bypasses this bottleneck, minimizing the HAMA response by replacing murine sequences with human framework homologous sequences [ 6 ]. (mdpi.com)
  • Using these new cell lines, we assayed a panel of HIV-1-positive sera and monoclonal antibodies (MAbs) for neutralization potency against several strains of HIV-1. (asm.org)
  • We reasoned that if two Mabs, one directed at gD and the other at gH/gL, block fusion more effectively than when either were used alone (additive), then their epitopes would be spatially distanced and binding of one would not directly interfere with binding of the other during fusion. (bvsalud.org)
  • Activating anti-CD3 mAbs mimic this force via their intrinsic binding mode. (dana-farber.org)
  • The 2D7 binding site mapped to the second extracellular loop of CCR5, whereas a group of mAbs that failed to block chemokine binding all mapped to the NH 2 -terminal region of CCR5. (rupress.org)
  • Efficient inhibition of an M-tropic HIV-1-derived envelope glycoprotein gp120 binding to CCR5 could be achieved with mAbs recognizing either the second extracellular loop or the NH 2 -terminal region, although the former showed superior inhibition. (rupress.org)
  • VEGF-A, commonly known as VEGF, is one member of a family of secreted glycoproteins that promote endothelial cell growth, survival, migration, and vascular permeability, all of which contribute to angiogenesis. (merckmillipore.com)
  • Interestingly, we show by reverse transcriptase-PCR that the PZR isoforms are differentially expressed in haematopoietic, endothelial and mesenchymal cells. (ox.ac.uk)
  • Both PZR and PZRb are present in CD133(+) precursors and endothelial cells, PZRb predominates in mesenchymal and committed myelomonocytic progenitor cells, and all three isoforms occur in erythroid precursor cell lines. (ox.ac.uk)
  • Analysis of human RA synovial tissue confirmed that PBEF immunolocalized in apical synovial membrane cells, endothelial cells, adipocytes, and lymphoid aggregates. (docme.ru)
  • The ability of NK cells to kill tumors and virus-infected cells and to produce cytokines is regulated by a balance between activating and inhibitory receptors. (sciencemag.org)
  • When stimulated by mesothelin, lentivirally transduced T cells were induced to proliferate, express the antiapoptotic gene Bcl-X L , and secrete multiple cytokines, all features characteristic of central memory T cells. (pnas.org)
  • In earlier studies, tumor cells expressing mesothelin have been shown to be killed by MHC Class I-restricted T cells ( 11 ). (pnas.org)
  • In conclusion, scopoletin might serve as lead compound for drug development because of its favorable activity against tumor cells with ABC-transporter expression, although NF-κB activation may be considered as resistance factor for this compound. (mdpi.com)
  • This process can be triggered by diverse membrane components, such as scavenger receptors, complement receptors, and Fc receptors ( 13 , 14 ). (asm.org)
  • and (ii) ofatumumab, a second-generation anti-CD20 antibody displaying increased complement-dependent cytotoxicity compared with rituximab, that was approved in 2009 for relapse/refractory CLL patients who failed fludarabine and alemtuzumab ( 18 ). (aacrjournals.org)
  • On the other hand, the innate immune response, which includes phagocytic cells, antimicrobial peptides, and the complement system, has been viewed to be primarily involved in the initial defense against infection. (jyi.org)
  • The CD11b/CD18 heterodimeric complex is also known as integrin alpha-M beta-2, Mac-1, and CR3 (complement receptor 3). (fishersci.ca)
  • We show direct binding of a CirpT to complement C5 and have determined the structure of the C5-CirpT complex by cryoelectron microscopy. (bvsalud.org)
  • Colds are generally mild, self-limited infections, and significant increases in neutralizing antibody titer are found in nasal secretions and serum after infection. (jci.org)
  • Drawing of the effects of diazoxide in the microglial reaction during MS. (1) Diazoxide (Dzx) binds to mitochondrial KATP channels, induces depolarization of the mitochondrial internal membrane (MIM) and potentiates the H+ gradient generated by the electron transport chain (ETC). This enhances both ATP synthesis and calcium concentration by activation of ATP synthase and the mitochondrial calcium uniporter (MCU), respectively. (intechopen.com)
  • In addition to activating B cells to proliferate, it has been shown that RV N in the RNP complex induces potent T helper cell responses resulting in long-lasting and strong humoral immune responses against RV. (jove.com)
  • A chemical released by cancer cells that induces motility, enabling the cells to metastasize. (thefreedictionary.com)
  • Cytomegaloviruses (CMV) reorganize membranous system of the cell in order to develop a virion assembly compartment (VAC). (frontiersin.org)
  • Particular emphasis will be given to the biological mechanisms underlying combination hypotheses, bispecific antibodies and other emerging modalities for delivery of combination therapies, as well as a discussion of the importance of effective clinical trial design. (nyas.org)
  • Our initial results demonstrated only a weak correlation, and we then examined more rigorously the underlying mechanisms for the observed reductions in plasma membrane expression of the GluR6a receptor mutants. (jneurosci.org)
  • Using a live cell fusion assay, we found that some Mab pairings blocked the fusion with different mechanisms while other had a similar mechanisms of action. (bvsalud.org)
  • These observations will be instrumental in determining the mechanisms whereby PZR isoforms regulate cell motility. (ox.ac.uk)
  • Our results provide insights into the mechanisms involved in S glycoprotein-mediated Alphacoronavirus entry and have implications for vaccine and therapeutic antibody design. (bvsalud.org)
  • This study illustrates that Shoc2 single-domain antibodies can be used to understand functional mechanisms governing complex multiprotein signaling modules and have promise in application for therapies that require modulation of the ERK1/2-associated diseases. (bvsalud.org)