Conformation of antigens. Medical search. Frequent questions

The most promising Ags were submitted to a more in-depth biophysical investigation of their structure and conformation stability, and for their capacity to interact with neutralising antibodies (Abs) and peptides. (europa.eu)

Respiratory syncytial virus vaccine, adjuvanted, contains recombinant glycoprotein F stabilized in the prefusion conformation (RSVPreF3). (biospace.com)
RSVpreF (Abrysvo, Pfizer) consists of a recombinant RSV F protein antigen (based on both the RSV-A and RSV-B subtypes), stabilized in the prefusion conformation (preF). (cdc.gov)

The overall objective of EuroNeut-41 was to design a vaccine that raises antibodies able to prevent HIV cell fusion by blocking the virus fusion protein gp41 in its pre-fusogenic conformation. (europa.eu)
To investigate antigen-antibody interactions and assess the potential of the most common epitope mapping techniques, we generated a series of mAbs against factor H binding protein (fHbp), a key virulence factor and vaccine antigen of Neisseria meningitidis. (rcsb.org)
Although the assembled VLPs do not have S protein spikes, they could be developed as formulations that can improve the immunogenicity of vaccines including S antigens, and further could be used as platforms that can carry S antigens of concern for various mutations. (nature.com)
Heptares' StaRs offer a breakthrough solution to the main challenge associated with making antibodies against GPCRs, namely producing purified and properly folded protein for use as an antigen against which antibodies are raised. (centerwatch.com)
StaRs enable antibody discovery by stabilizing the GPCR protein outside the cellular membrane in the correct conformation. (centerwatch.com)
Antibodies against the NANP repeat of circumsporozoite protein (CSP), the major surface antigen of Plasmodium falciparum (Pf) sporozoites, can protect from malaria in animal models but protective humoral immunity is difficult to induce in humans. (rcsb.org)
The Seattle team suggests these differences may arise because the vaccine presents the viral protein in slightly different conformations. (hpnonline.com)
Shortly after SARS-CoV emerged at the turn of the 21st century, the spike (S) protein (particularly in its native conformation) was identified as the immunodominant antigen of the virus3. (who.int)
The protein is in the inward-facing conformation with Cavity 1 open to the cytosol for substrate recruitment, the Leucine Plug intact, and Cavity 2 completely occluded. (proteopedia.org)
which is occluded when the protein in is the inward-facing conformation, is now open to the extracellular space and able to release the substrate. (proteopedia.org)
Determining the affinity of an antibody binding to its antigen is the first step in predicting the function in a physiological environment where other competing protein interactions may be present. (lu.se)
This importance is focussed on the target binding site - epitope, where epitope selection as a part of design thinking beyond traditional antigen selection using whole cell or whole protein immunisation can positively impact success. (preprints.org)
Nanobodies have been employed effectively to trap transient conformations of medically relevant proteins for structural biology, facilitate non-invasive diagnostic imaging, imaging of dynamic processes in the cell, super resolution imaging of protein complexes , point of care diagnostic biosensors and as next generation cancer and SARS-CoV-2 therapies. (edu.au)
Endocytosis of CEA was independent of native protein conformation since performic acid oxidized CEA and glycopeptides produced by pepsin digestion were inhibitory. (duke.edu)
Such antigen preparations do not always accurately mimic native parasite protein conformations, including post-translational modifications. (biomedcentral.com)
This study tests the hypothesis that glutathione (GSH) reacts with MDI to form quasi-stable conjugates, capable of mediating the formation of MDI-conjugated "self" protein antigens, which may participate in pathogenic inflammatory responses. (cdc.gov)

N-Linked glycosylation regulate both conformation and immune related functions of ICAM receptors. (nih.gov)
Shark novel antigen receptors: the next generation of biologic therapeutics? (elsevierpure.com)
Dive into the research topics of 'Shark novel antigen receptors: the next generation of biologic therapeutics? (elsevierpure.com)
In 1940, Linus Pauling proposed his template theory of antibody formation, one of many such theories that rejected Paul Ehrlich's selective theory of preformed "receptors" (antibodies), assuming instead a direct molding of antibody shapes onto that of the antigen. (ucpress.edu)

GSK specifically describes AREXVY as "an injection that contains lyophilized recombinant respiratory syncytial virus glycoprotein F stabilized in pre-fusion conformation (RSVPreF3) as the antigen component. (goodwinlaw.com)

Quantitative measurements of antibody affinity for antigen can be made by equilibrium dialysis. (sigmaaldrich.com)

VLPs are highly immunogenic and can induce elevated titers of neutralizing antibodies, even without adjuvants, thanks to the maintenance of the native conformation of viral proteins presenting repetitive epitopes to the host immune system cells. (nature.com)
MVI is taking steps to address the possibility that the leading TBV antigens may be poorly immunogenic when delivered as soluble recombinant proteins with adjuvant in humans. (malariavaccine.org)
Antibody-antigen affinity is often evaluated with isolated proteins. (lu.se)
My research focuses on understanding the intricate molecular mechanisms that determine the vast repertoire of peptide antigens displayed by the proteins of the Major Histocompatibility Complex for immune surveillance by T cells and Natural Killer cells. (upenn.edu)
In recent work, our team found that the dynamic plasticity of MHC-I proteins, occurring over a range of timescales from microseconds to milliseconds, plays an essential role in their peptide selector function though the sampling of minor, "excited-state" conformations. (upenn.edu)
Our detailed biophysical characterization of the molecular chaperone TAPBPR provided us with a high-resolution view of peptide exchange on MHC-I proteins and led to the development a high-throughput methodology for generating barcoded MHC tetramer libraries encompassing hundreds of unique antigen specificities. (upenn.edu)
Indeed, Spike proteins induce the highest neutralising antibody (nAb) titres of any coronavirus antigens [7] , making them prime candidates for vaccine development, as they could preclude SARS-CoV-2-ACE2 interaction entirely to halt COVID-19 in its tracks. (thenativeantigencompany.com)
These analyses have mainly been carried out by ELISA using recombinant proteins or synthetic peptides usually representing subdomains of malarial proteins as test antigens. (biomedcentral.com)

NANP repeat recognition was largely mediated by germline encoded and immunoglobulin (Ig) heavy-chain complementarity determining region 3 (HCDR3) residues, whereas affinity maturation contributed predominantly to stabilizing the antigen-binding site conformation. (rcsb.org)
It has been hypothesized that development of effective IgG-mediated anti-parasite immunity depends on the maturation of antibody responses, not only in terms of their antigen specificities and affinity maturation, but also in terms of class-switching implying that the progressive development of malaria immunity in older children can be attributed to a switch of anti-parasite antibodies from the non-cytophilic to the cytophilic subclasses [ 3 , 17 ]. (biomedcentral.com)

Fifty-one vaccine candidates were designed mainly to mimic fusion intermediate conformations of gp41 and in some instance to increase exposure of the 2F5/4E10 epitopes. (europa.eu)
Linear epitopes identified by conventional mapping techniques only partially reflect the immunogenic properties of the epitope in its natural conformation, thus limiting the success of this approach. (rcsb.org)
Collectively, these data show that linear epitope mapping techniques provide useful but incomplete descriptions of B-cell epitopes, indicating that increased efforts to fully characterize antigen-antibody interfaces are required to understand and design effective immunogens. (rcsb.org)
Cross-reactivity refers to an antibody or population of antibodies binding to epitopes on other antigens. (sigmaaldrich.com)
This can be caused either by low avidity or specificity of the antibody or by multiple distinct antigens having identical or very similar epitopes. (sigmaaldrich.com)
Like antibodies, antigens can be multivalent, either through multiple copies of the same epitope, or through the presence of multiple epitopes that are recognized by multiple antibodies. (sigmaaldrich.com)

These data highlight the phenotypic and functional diversity of the B cell memory compartment, in their temporal kinetics, antigen-binding capacities and association with cTFH cells, and are important parameters for consideration in assessing vaccine-induced immune responses. (bvsalud.org)

Western Blot profiling of blood-stage parasite antigens displaying reactivity with individual plasma samples in terms of their subclass specificities was conducted. (biomedcentral.com)

Significant challenges have been encountered in producing sexual sporogonic mosquito (SSM) antigens that adopt native conformations in recombinant systems due to multiple cysteine residues and complex tertiary structures. (malariavaccine.org)

Expression level and antigen peptide (HER2 63-71 )-binding capability of the MHC I were evaluated on bacterial magnetic particles (BacMPs, also known as magnetosomes). (elsevierpure.com)

Many of these factors stem from the location of the epitope that can affect accessibility of the antibody to the epitope at a cellular or molecular level, direct inhibition of target antigen activity, conservation of function despite escape mutations, and even non-competitive inhibition sites. (preprints.org)
It is controlled by three major factors: antibody epitope affinity, the valence of both the antigen and antibody, and the structural arrangement of the interacting parts. (sigmaaldrich.com)
Ultimately these factors define the specificity of the antibody, that is, the likelihood that the particular antibody is binding to a precise antigen epitope. (sigmaaldrich.com)
Cross-reactivity is sometimes desirable when one wants general binding to a related group of antigens or when attempting cross-species labeling when the antigen epitope sequence is not highly conserved during evolution. (sigmaaldrich.com)

In parallel, we are supporting the development of a panel of biochemical assays to better characterize each of the lead antigens as they become available and complement the small animal immunogenicity assessments. (malariavaccine.org)

It has been hypothesized that the initial antibody responses against parasite antigens upon first few Plasmodium falciparum infections is dominated by non-protective IgG2/IgG4 and IgM antibodies, which then gradually develop into protective response dominated by cytophilic IgG1 and IgG3 antibodies. (biomedcentral.com)

The mRNA vaccines can encode multiple antigens, strengthening the immune response against pathogens and enabling the targeting of multiple microbial variants [19] . (researchgate.net)
Through the incorporation of novel computational methods for predicting antigen changes to model-informed drug discovery and development, superior vaccines and antibody-based therapeutics or diagnostics can now be more easily designed to mitigate failures. (preprints.org)

In the process of engaging the antigen, antibodies complementarity-determining regions (CDR) may need to navigate interactions with or concealment by lipid molecules. (elifesciences.org)
Immunochemical techniques capitalize upon the extreme specificity, at the molecular level, of each immunoglobulin for its antigen, even in the presence of high levels of contaminating molecules. (sigmaaldrich.com)

Recently, a protocol for yeast surface display of a synthetic nanobody library was published, allowing the identification of high-affinity nanobodies to a particular antigen, without the immunisation of animals. (edu.au)

The most active T cell endogenous inhibitory pathway is the immunoglobulin superfamily such as CD28/cytotoxic T lymphocyte antigen-4 (CTLA-4): B7-1/B7-2 receptor/ligand grouping, which plays a central role in coordinating immune responses [ 7 , 8 ]. (hindawi.com)

Join us on November 30th for a virtual meeting bringing together experts across disciplines to discuss developments in antigen discovery, preclinical vaccine development and clinical advances in cancer vaccine therapy, and reflect on the ongoing challenges and necessities in the field. (nature.com)

Also, it's possible that mRNA delivery may change the way antigens are presented to the immune system, leading to differences in the antibodies that get produced. (hpnonline.com)

In the present study, there was no evidence for switching of antibody responses from non-cytophilic to cytophilic subclasses against blood-stage parasite antigens as a likely mechanism for induction of protective immunity against malaria. (biomedcentral.com)
The subclass profile of naturally occurring IgG responses has therefore been extensively studied for several major blood-stage malaria vaccine candidate antigens. (biomedcentral.com)

The 414K-MDI conjugation appears to covalently cross- link GSH to albumin via GSH's NH2-terminus, a unique conformation possibly resulting from cyclized mono(GSH)-MDI or asymmetric ( S , N -linked) bis(GSH)-MDI conjugates. (cdc.gov)
Upon co-incubation of GSH-MDI reaction products with human albumin, MDI was rapidly transferred to specific lysines of albumin, and the protein's native conformation/charge was altered, based on electrophoretic mobility. (cdc.gov)

The CDRs of V H and V L are held in close proximity by the FRs, and amino acid residues within the CDRs bind the antigen. (justia.com)

Scanning and transmission electron microscopy were conducted to confirm particle image and to visualize the conformation of HPV16 vaccine particles released from microparticle formulation. (cdc.gov)

This is tightly bound with a syn-conformation and the s-face is positioned towards a sugar substrate. (prospecbio.com)
Guided by these determinations, the antibody is accordingly modified (altered) to improve upon, e.g., antibody/antigen binding by modifying at least one amino acid residue to decrease the binding free energy between the antibody and antigen when bound in a solvent. (justia.com)

De Palma and colleagues develop a dendritic cell therapy based on dendritic cell progenitors engineered to produce IL-12 and FLT3L and show antigen-agnostic reduction of tumor burden that can be exploited for combination therapy in glioma. (nature.com)
Recent clinical evidence suggests that high serum levels of the tumor‑produced mucin 16 (MUC16) and cancer antigen 125 (CA125) have a negative impact on the effectiveness of RTX clinical activity in up to 40% of patients with follicular lymphoma. (spandidos-publications.com)

Conversely, mutations reducing CDR-H3 hydrophobicity (e.g. 4E10 H100-H102 Trp-Trp motif to Ala-Ala or Asp-Asp) only marginally affect antigen affinity, but drastically reduce neutralization activity and weakened association to lipid bilayers in parallel 7 , 21 , 28 , 29 . (elifesciences.org)

Accordingly, there remains a need for antibodies that do not provoke a strong immune response but yet bind strongly to their antigens and methods for identifying such antibodies. (justia.com)

In this work, the main conformations and interactions between the receptor-binding domain (RBD) of spike glycoprotein gp120 of HIV-1 and the IgG1-b12 mAb are studied. (ibecbarcelona.eu)
Accelerated molecular dynamics (aMD) and ab initio hybrid molecular dynamics have been combined to determine the most persistent interactions between the most populated conformations of the antibody-antigen complex under physiological conditions. (ibecbarcelona.eu)
Molecular determinants of chaperone interactions on MHC-I for folding and antigen repertoire selection. (upenn.edu)
The specific association of antigens and antibodies is dependent on hydrogen bonds, hydrophobic interactions, electrostatic forces, and Van der Waals forces. (sigmaaldrich.com)

They present a range of surface antigens in a native conformation and have natural properties like immunogenicity, self-adjuvation and uptake by immune cells. (bioprocessintl.com)

Their three-complementarity determining region (CDR) loops contain all the necessary biochemical features to achieve nano-molar binding affinity to a given antigen, and have superior qualities for many applications relative to IgG's, due to their smaller size and stability. (edu.au)
Avidity is perhaps a more informative measure of the overall stability or strength of the antibody-antigen complex. (sigmaaldrich.com)

Adoptive cell therapy (ACT) with chimeric antigen receptor T (CAR-T) cells can restore the activity of exhausted T cell through reprogramming and is widely used in the treatment of relapsed/refractory (r/r) hematological malignancies. (hindawi.com)
The results show the most persistent receptor-binding mapping in the conformations of the antibody-antigen interface in solution. (ibecbarcelona.eu)
Scholars@Duke publication: Receptor-mediated endocytosis of carcinoembryonic antigen by rat alveolar macrophages in vitro. (duke.edu)

Upon the detection of either type of the antigen preparation, the lowest concentration of the antigen detectable in buffer with pH 5.1 has been found to be approximately equal, amounting to ~10 -14 M. This value has been found to be similar upon the use of either type of molecular probes. (preprints.org)
Uptake of carcinoembryonic antigen (CEA) by isolated rat alveolar cells was time, temperature, and concentration dependent (Kuptake = 2.4 x 10(-7) M). Pretreatment of the alveolar cells with colchicine inhibited internalization of CEA. (duke.edu)
Cross-reactivity can result in over- or under-estimation of the antigen concentration and is problematic in immunoassays. (sigmaaldrich.com)

Finally, frequencies of activated (PD-1+ICOS+) circulating follicular helper T cells (cTFH), particularly of the CXCR3-CCR6- cTFH2 cell phenotype, at their peak expansion, strongly predicted antigen-binding capacity of IgG+ MBC. (bvsalud.org)

Nanovaccines can improve antigen presentation, targeted delivery, stimulation of the body's innate immune system, and a strong T-cell response without putting people at risk. (researchgate.net)

The four framework regions largely adopt a β-sheet conformation and the CDRs form loops connecting, and in some cases forming part of, the β-sheet structure. (justia.com)

Interestingly, most of these bnAbs show affinity for lipid components and freely associate with lipid bilayers 5 - 8 or cultured cells, even in the absence of antigen 17 - 23 . (elifesciences.org)
CD20 is a B-cell-specific antigen expressed on malignant FL cells. (spandidos-publications.com)
Uptake of 125I-labeled CEA by alveolar cells required divalent cations and was inhibited by cold CEA and nonspecific cross-reacting antigen (NCA). (duke.edu)

Middle: Side-on view of Spike trimer in open conformation. (thenativeantigencompany.com)
Right: Top-down view of Spike trimer in open conformation. (thenativeantigencompany.com)

Researchers hoped that such antibodies would be no more foreign to the human body than a genuine human antibody, but the utility of such antibodies has been restricted, at least in some cases, by a reduction in the antibody's affinity for the antigen. (justia.com)

One molecule of ATP is hydrolyzed to transport substrates across the cell membrane while the second molecule of ATP is hydrolyzed to reset the transporter to its inward-facing conformation. (proteopedia.org)
Here, the antigen-specific B cell response to tetanus toxoid (TTd) booster vaccination was examined in healthy adults, using a dual-TTd tetramer staining flow cytometry protocol. (bvsalud.org)

It is informative to also be able to assess antibody binding to a bacterial surface where many antigens might be present, including multiple copies of the specific antigen the antibody recognizes, and in a context where the antigen might be in a more natural conformation. (lu.se)

Using the case-control design 30 animals identified as having supraspinous bursitis were compared with 90 animals rendomly selected, without bursitis- but with other characteristics (sex, background, lot, conformation) similar to those affected. (usp.br)

These are of a weak, noncovalent nature, yet some of the associations between antigen and antibody can be quite strong. (sigmaaldrich.com)

We believe that by combining Heptares' unique StaR platform for generating stable GPCRs as antigens with our antibody discovery technology, we will be able to unlock the immense potential of therapeutic antibodies against GPCRs. (centerwatch.com)

The project has been structured in 3 main pathways or "tracks": a Discovery track, aiming at designing gp41-based antigens (Ag) using an iterative improvement process, and two development tracks (Parenteral and Mucosal) to determine the safety and immunogenicity of the Ags and the optimal administration conditions before selecting the most promising candidate for clinical development. (europa.eu)

Affinity constants can be determined for monoclonal antibodies, but not for polyclonal antibodies, as multiple bond formations take place between polyclonal antibodies and their antigens. (sigmaaldrich.com)
Usually there are multiple bond formations observed, ensuring relatively tight binding between antibody and antigen. (sigmaaldrich.com)

The multivalency of most antigens and antibodies enables them to interact to form a precipitate. (sigmaaldrich.com)

Moreover, VLPs offer interesting biotechnological advantages as they can serve as scaffolds for presenting heterologous antigens capable of inducing immune responses against other infectious diseases. (nature.com)

Anatomy17

Organisms10

Diseases1

Chemicals and Drugs125

Analytical, Diagnostic and Therapeutic Techniques and Equipment44

Phenomena and Processes62

Disciplines and Occupations3

Technology, Industry, Agriculture1

Information Science6

Health Care4

Neutralising antibodies1

Stabilized in the prefusion conformation2

Protein16

Receptors4

Glycoprotein F stabilized1

Antibody Affinity1

Proteins8

Affinity maturation2

Epitopes6

Kinetics1

Specificities1

Recombinant1

Peptide1

Epitope4

Characterize1

Plasmodium1

Vaccines2

Molecules2

Immunisation1

Immunoglobulin1

Vaccine development1

MRNA1

Malaria2

Albumin2

Residues1

Particles1

Bound2

Tumor2

Mutations1

Immune response1

Interactions4

Native1

Stability2

Receptor3

Concentration3

Strongly1

Presentation1

Adopt1

Cells3

Spike2

Reduction1

Cell2

Assess1

Characteristics1

Associations1

Unique1

Discovery1

Multiple2

Interact1

Responses1