Results Our artificial antigen-presenting cells expanded both polyclonal T cells and MART-1-specific CD8+ T cells in a more efficient manner than the other systems. Stimulation with artificial antigen-presenting cells allows for the generation of viable T cells displaying an immunophenotype consistent with in vivo potential for persistence, without increasing the frequency of regulatory T cells. The starting specificity of anti MART-1 CD8+ T cells was preserved after stimulation with artificial antigen-presenting cells and it was statistically greater when compared to the activity of the same cells expanded with the other systems. Finally, our artificial antigen-presenting cells proved to be suitable for large-scale application, minimizing the volume and the costs of T-cell expansion. ...
An antigen-presenting cell (APC) or accessory cell is a cell that displays antigen complexed with major histocompatibility complexes (MHCs) on their surfaces; this process is known as antigen presentation. T cells may recognize these complexes using their T cell receptors (TCRs). These cells process antigens and present them to T-cells. Almost all cell types can serve as some form of APC. They are found in a variety of tissue types. Professional antigen-presenting cells, including macrophages, B cells and dendritic cells, present foreign antigens to helper T cells, while other cell types can present antigens originating inside the cell to cytotoxic T cells. In addition to the MHC family of proteins, antigen presentation relies on other specialized signaling molecules on the surfaces of both APCs and T cells. Antigen-presenting cells are vital for effective adaptive immune response, as the functioning of both cytotoxic and helper T cells is dependent on APCs. Antigen presentation allows for ...
Definition of antigen-presenting cell in the Financial Dictionary - by Free online English dictionary and encyclopedia. What is antigen-presenting cell? Meaning of antigen-presenting cell as a finance term. What does antigen-presenting cell mean in finance?
Looking for Antigen-presenting cells? Find out information about Antigen-presenting cells. A morphologically distinct epidermal cell adjacent to, and apparently functionally associated with, guard cells on the leaves of many plants. Explanation of Antigen-presenting cells
TY - JOUR. T1 - Antigen-presenting cells pulsed with unfractionated tumor-derived peptides are potent tumor vaccines. AU - Nair, Smita K.. AU - Boczkowski, David. AU - Snyder, David. AU - Gilboa, Eli. PY - 1997/3/20. Y1 - 1997/3/20. N2 - Vaccination with peptides isolated from tumor cells circumvents the need for identifying specific tumor rejection antigens and extends the use of active immunotherapy to the majority of cancers where specific tumor antigens have not yet been identified. In this study, we examined the efficacy of tumor vaccines composed of unfractionated tumor peptides presented by antigen-presenting cells (APC) to induce cytotoxic T lymphocyte (CTL) responses and tumor immunity. RMA-S cells pulsed with peptides isolated from ovalbumin (OVA)-expressing tumor cells were highly effective at inducing primary, OVA-specific CTL responses in vitro and priming CTL responses in vivo. In addition, tumor peptide-pulsed RMA-S cells induced protective immunity in mice when challenged with ...
TY - JOUR. T1 - Flow cytometry used for the analysis of calcium signaling induced by antigen-specific T-cell activation. AU - Réthi, Bence. AU - Detre, Cynthia. AU - Gogolák, Péter. AU - Kolonics, Attila. AU - Magócsi, Mária. AU - Rajnavölgyi, Éva. PY - 2002/4/1. Y1 - 2002/4/1. N2 - Background: In this study, the effect of antigen-presenting cells (APC), peptide concentration, and CD28 costimulation on calcium signaling, induced by antigen-specific T-cell activation, was studied by flow cytometry. Methods: We used two experimental approaches, which differed in their time scale and in the duration of the T cell-APC interaction, to measure the increase of intracellular free calcium levels ([Ca2+]i) in activated T cells: (1) Fluo-3-loaded T cells were activated by cocentrifugation with peptide-loaded APC and the kinetics of fluorescence intensity changes was monitored continuously and (2) peptide-loaded APC and T cells were mixed, cocultured, and the fluorescence intensity was measured at ...
Interaction between antigen-specific T cells and antigen presenting cells (APC) cognate ligand involve reorganization of the cytoskeleton and recruitment of adhesive and signaling molecules to the site of intercellular contact.
TY - JOUR. T1 - Costimulation of antitumor immunity by the B7 counterreceptor for the T lymphocyte molecules CD28 and CTLA-4. AU - Chen, Lieping. AU - Ashe, Stephanie. AU - Brady, William A.. AU - Hellström, Ingegerd. AU - Hellström, Karl Erik. AU - Ledbetter, Jeffrey A.. AU - McGowan, Patrick. AU - Linsley, Peter S.. PY - 1992/12/24. Y1 - 1992/12/24. N2 - Interaction of the B7 molecule on antigen-presenting cells with its receptors CD28 and CTLA-4 on T cells provides costimulatory signals for T cell activation. We have studied the effects of B7 on antitumor immunity to a murine melanoma that expresses a rejection antigen associated with the E7 gene product of human papillomavirus 16. While this E7+ tumor grows progressively in immunocompetent hosts, cotransfection of its cells with B7 led to tumor regression by a B7-dependent immune response mediated by CD8+ cytolytic T lymphocytes. The immune response induced by E7+B7+ tumor cells also caused regression of E7+ B7- tumors at distant sites and ...
Tolerogenic antigen-presenting cells (APCs) are attractive agents for the treatment of autoimmune and inflammatory diseases that are mediated, at least in part, by antigen-specific autoreactive T...
Recent gene expression studies have suggested that down-regulation of HLA class II expression has a major biological effect reflected in clinical tumor characteristics and outcome. This has been shown for B-cell lymphomas, that naturally express HLA class II on lymphoma cells (8, 22), but also for carcinomas in which HLA class II can be expressed on the antigen-presenting cells within the tumor (24). It is increasingly appreciated that not only HLA class I but also class II is essential for mounting an adequate antitumor immune response. Antigen presentation via HLA class II is indispensable to activate a CD4+ T-cell population that may induce a CD8+ T cell-mediated cytotoxic antitumor response (25, 26) and recruit additional effector cell populations, such as macrophages (26, 27). In carcinomas, an immune-mediated antitumor response is mainly mediated by professional antigen-presenting cells.. In B-cell lymphomas, both professional antigen-presenting cells as well as the tumor B cells may play ...
To mount an immune response, T lymphocytes must successfully search for foreign material bound to the surface of antigen-presenting cells. How T cells optimize their chances of encountering and responding to these antigens is unknown. T cell motility in tissues resembles a random or Levy walk and is regulated in part by external factors including chemokines and lymph-node topology, but motility parameters such as speed and propensity to turn may also be cell intrinsic. Here we found that the unconventional myosin 1g (Myo1g) motor generates membrane tension, enforces cell-intrinsic meandering search, and enhances T-DC interactions during lymph-node surveillance. Increased turning and meandering motility, as opposed to ballistic motility, is enhanced by Myo1g. Myo1g acts as a turning motor and generates a form of cellular flânerie. Modeling and antigen challenges show that these intrinsically programmed elements of motility search are critical for the detection of rare cognate antigen-presenting
The initial step in the development of an immune response is the recognition of Ag by the professional APCs. At present, three major types of APCs have been described: dendritic cells (DCs),3 macrophages, and B lymphocytes. Discriminatory handling of Ags by APCs occurs at different levels. At the cell surface, APCs are endowed with various endocytic machineries. Macrophages and DCs, in addition to receptor-independent macropinocytosis, have a plethora of surface-expressed receptors through which they capture Ags. In contrast, B lymphocytes are able to endocytose exclusively by Ag-specific, surface-expressed Igs (also known as B cell receptors or BCRs). The fate of the Ag within an APC may vary depending on the cell type. Thus, the content of lysosomal proteases and the amount and distribution of MHC II molecules determine the immunological fate of the endocytosed Ag (11). Indeed, as compared with B lymphocytes and DCs, macrophages have a very high endocytosing capacity, are rich in lysosomal ...
Immune cells have been recruited, trained, and armed to fight solid tumors. And now theyre being deployed. Soon, well hear which T cells, NK cells, and antigen-presenting cells are up for promotion.
¦ ̷ ̷ ̷ ̷ ̷ ̷ ̷ ̷ ¦ ̷ ̷ ̷ ̷ noun : any of various cells (as a macrophage or a B cell) that take up and process an antigen into a form that when displayed at the cell surface in combination with a molecule of the major histocompatibility…
The overall goal of this proposal is to provide the principal investigator (PI) with the experiences and skills necessary to become an independent researcher, w...
The interaction between a CD4+ TH cell and an antigen presenting cell (APC) is a finely tuned event in adaptive immunity. The affinity is dictated by the T cell receptor (TCR) and the characteristics of antigenic peptide ...
0392] Adams, D. O., and Hamilton, T. A. Molecular transduction mechanism by which IFN-gamma and other signals regulate macrophage development. Immunol. Rev., 22: 5-27, 1987. [0393] Alexander, J., Rayman, P., Edinger, M., Connelly, R., Tubbs, R., Bukowski, R., Pontes, E., Finke, J., TIL from renal-cell carcinoma: Restimulation with tumor influences proliferation and cytolytic activity. Int. J. Cancer 45:119, 1990. [0394] Alexander, M. A., Bennicelli, J., and Guerry, D. Defective antigen presentation by human melanoma cell lines cultured from advanced, but not biologically early disease. J. Immunol., 142: 4070-4078, 1989. [0395] Altmann, D. M., Hogg, N., Trowsdale, J., and Wilkinson, D. Cotransfection of ICAM-1 and HLA-DR reconstitutes human antigen-presenting cell function in mouse L cells. Nature (Lond.). 338: 512-514, 1989. [0396] Anichini, A., Fossati, G., Parmiani, G., Clonal analysis of cytotoxic T-lymphocyte response to autologous human metastatic melanoma. Int. J. Cancer 25:683, 1985. ...
Cerulenin is an antibiotic that inhibits eukaryotic lipid and sterol synthesis and blocks lipid modification of proteins. The effect of cerulenin on the ability of accessory cells to present antigen to T cells was investigated. This antibiotic strongly inhibits the ability of accessory cells to present antigen to murine T-T hybrids. This effect is observed for multiple distinct antigens including L-glutamic acid60-L-alanine30-L-tyrosine10, bovine insulin, L-glutamic acid56-L-lysine35-L-phenylalanine9, and ovalbumen. Presentation by both macrophage and B lymphoblastoid cell lines is inhibited. The ability to effectively pulse these cells with antigen is inhibited but not the ability of these same cells to present antigen that they have previously processed. Furthermore, this inhibition is selective as it can occur without significant inhibition of the antigen-presenting cell protein or DNA synthesis. Cerulenin does not inhibit antigen uptake or catabolism as assessed with labeled antigen. By ...
Trogocytosis (Greek: trogo; gnaw) is a process whereby lymphocytes (B, T and NK cells) conjugated to antigen-presenting cells extract surface molecules from these cells and express them on their own surface. The molecular reorganization occurring at the interface between the lymphocyte and the antigen-presenting cell during conjugation is also called "immunological synapse". First indication for the existence of this process dates back late 70s when several research groups reported on the presence of unexpected molecules such as Major Histocompatibility complex molecules (MHC) on T cells. The notion that membrane fragments, and not isolated molecules, could be captured by T cells on antigen-presenting cells was suggested by the capture of MHC molecules fused to the green fluorescent protein (GFP) in their intracellular portion. The demonstration that membrane fragments were involved in this transfer process came when fluorescent probes incorporated in the plasma membrane of the ...
P>Adenosine is a well-described anti-inflammatory modulator of immune responses within peripheral tissues. Extracellular adenosine accumulates in inflamed and damaged tissues and inhibits the effector functions of various immune cell populations, including CD8 T cells. However, it remains unclear whether extracellular adenosine also regulates the initial activation of naive CD8 T cells by professional and semi-professional antigen-presenting cells, which determines their differentiation into effector or tolerant CD8 T cells, respectively. We show that adenosine inhibited the initial activation of murine naive CD8 T cells after alpha CD3/CD28-mediated stimulation. Adenosine caused inhibition of activation, cytokine production, metabolic activity, proliferation and ultimately effector differentiation of naive CD8 T cells. Remarkably, adenosine interfered efficiently with CD8 T-cell priming by professional antigen-presenting cells (dendritic cells) and semi-professional antigen-presenting cells ...
Granulocytes, the most abundant types of leukocytes, are the first line of defense against pathogen invasion. However, the plasticity and diversity of granulocytes have been increasingly revealed, especially with regards to their versatile functions in orchestrating adaptive immune responses. A substantial body of recent evidence demonstrates that granulocytes can acquire the function as antigen-presenting cells (APC) under pathological or inflammatory conditions. In addition, they can acquire surface expression of MHC class II and co-stimulatory molecules as well as T cell stimulatory behavior when cultured with selected cytokines. The classic view of granulocytes as terminally differentiated, short-lived phagocytes, is therefore changing to phenotypically and functionally heterogeneous cells that are engaged in cross-talk with other leucocyte populations and provide an additional link between innate and adaptive immunity. In this brief review, we summarize the current knowledge on the antigen
We apply three-dimensional confocal microscopy and time lapse video-microscopy techniques to visualize molecular dynamics at the immunological synapse (IS). The major contribution of our research team to the field during the last few years has been to contribute to define the biological function of the IS. We propose that the IS has no specific function in T cell activation, on the contrary it is the "manifestation" of the inter-cellular communication occurring during T cell/APC cognate interactions. Our results show that: i) the large-scale molecular clustering and segregation characteristic of a mature IS is not required for productive TCR triggering and for T cell activation (indeed some responses such as cytotoxicity can occur in the absence of mature IS formation); ii) T cells form different types of synapses depending on the strength and quality of antigenic stimulation; iii) synapses can be interrupted and re-formed while T cells add-up the interrupted signals; iv) synapses are not static ...
The study of the ontogeny of skin APCs also provides a unique opportunity to evaluate the development and, thus, the phenotype of their precursor cells. In addition, despite considerable research, the relationship among LCs, dermal DCs, and skin macrophages still remains unclear, not least because of the high plasticity of precursors to differentiate into each of these cells in different microenvironments (7, 12, 15). In this study, we show that at 9 wk EGA, skin macrophages and DCs can already be phenotypically separated by the distinct expression of the DC marker CD1c on some HLA-DRhigh cells. HLA-DRhigh leukocytes are capable of phagocytosing bacteria, up-regulating costimulatory molecules, and stimulating proliferation of allogeneic T cells in vitro, thus confirming their DC nature. In contrast, HLA-DRlow skin macrophages neither express CD1c nor up-regulate costimulatory molecules during culture. Collectively, these data show that at 9 wk EGA, skin macrophages and DCs can already be ...
... cells (APCs), which trigger T-cell effector functions. insensitive to cellular perturbations and the force-dependent off-rates were indistinguishable for native and recombinant TCRs. These data present novel features of TCRCpMHC kinetics that are regulated by the cellular environment, underscoring the limitations of 3D kinetics in predicting T-cell functions and calling for further elucidation of the underlying molecular and cellular mechanisms that regulate 2D kinetics in physiological settings. and the native proteins Rabbit polyclonal to SZT2 expressed on cell surface, or biomechanical rules by pressure. Our new SPR measurements (3D, recombinant, zero pressure) revealed much faster off-rates than previously reported [29, 30]. This is usually consistent with our 2D measurements with BFP for both the recombinant and the native TCRs at zero pressure. Under tensile causes, both the recombinant and the native ...
La CD154, anche chiamata CD40 ligando o semplicemente CD40L, è una proteina espressa soprattutto nei linfociti T attivati e facente parte della superfamiglia del TNF[1]. Si lega al CD40 presente sulle antigen-presenting cell (APC) agendo come co-attivatore[1]. In particolare, il legame CD40/CD40L attiva i linfociti B stimolandoli a formare i centri germinativi, porta le cellule dendritiche ad aumentare la produzione di molecole stimolatorie e citochine (licensing delle cellule dendritiche), e aumenta lattività microbicida dei macrofagi. ...
Orgcme). 2 PMN as Antigen-presenting Cells 421 Page 463 п422 11 Polymorphonuclear Neutrophils as Antigen-presenting Cells ous TT was sufficient to induce proliferation of TT-specific T cells provided that the PMN had been pre-incubated with IFN-c and GM-CSF.
The induction of tissue-specific autoimmunity presents a new principle in the therapy of many important cancers (24 , 25) . In the course of autoimmune diseases, autoantibodies are able to increase the efficiency of antigen capturing by professional antigen-presenting cells (26 , 27) , leading to the enhancement of the presentation of nondominant pathogenic determinants and T-cell activation (28) . It was therefore interesting to investigate the humoral response revealed in the sera of cured rats after treatment by apoptotic bodies/IL-2 (13) and the mechanisms involved.. In this paper, we report that the p67 kDa protein recognized by the sera of rats cured and subsequently immunized against cancer is a proteolytic fragment of BARD1. This identity was confirmed by: (a) the cloning of the rat BARD1 by immunoscreening with the sera of cured rats; (b) the demonstration that the full-length BARD1 (Mr 97,000) is expressed in colon and mammary cancer cells, whereas the truncated form (Mr 67,000) is ...
Dendritic cells (DC) are professional antigen-presenting cells that orchestrate immune responses. The human DC population comprises two main functionally specialized lineages, whose origins and differentiation pathways remain incompletely defined. Here, we combine two high-dimensional technologies-s …
Did you know that, as an author affiliated with University of Ghana, payment of your article-processing charge may be covered by University of Ghanas Foundation membership?. As an author from Ghana, BioMed Central and SpringerOpen article-processing charges (APCs) are covered by the country waiver fund. Please find more information regarding your funding here.. ...
Synonyms for accessory cell in Free Thesaurus. Antonyms for accessory cell. 24 synonyms for cell: room, chamber, lock-up, compartment, cavity, cubicle, dungeon, stall, unit, group, section, core, nucleus, caucus, coterie, electric cell. What are synonyms for accessory cell?
Cell-mediated immunity (CMI) is explored and key cells are discussed, eg killer T, helper T, gdT and NK cells. The importance of antigen-presenting cells and CD molecules are considered. The structure and physiology of the major histocompatibility complex is highlighed. The roles of cytokines, leycocyte migration and inflammation are discussed and killing mechanism are explored ...
BIOLOGY 206 CHAPTER 22: NONSPECIFIC BODY DEFENSESS IMMUNITY See flow chart. 5. Pus is a mix of dead or dying WBCs, broken-down ... will never meet its antigen, and never be involved in immune response. C. Antigen-Presenting Cells .... ...
(2012) Zhu et al. PLoS ONE. Dendritic cells (DCs) regulate innate and acquired immunity through their roles as antigen-presenting cells. Specific subsets of mature DCs, including monocyte-derived and lymphoid-derived DCs, can be distinguished based on distinct immunophenotypes and functional prop...
Cells, Dendritic Cells, Patients, Antigen, Cell, Therapeutic, Production, Immunotherapy, Treatment, Antigen-presenting Cells, Blood, Human, Populations, Monocyte, Diseases, T Cells, Syndrome, Cancer, Phenotype, Vaccination
Part 2: Once youve evaluated performance, refer to the four most frequently used leveling methods. by Jim Strafford, CEDC, MCS-P In
therapy.. In addition, intralesional therapy with either of two cytokines-namely, granulocyte-macrophage colony-stimulating factor (GM-CSF, Leukine)1 and interleukin-2 (IL-2, Proleukin)2-each gave promising results, but they were never used sequentially or in combination. Intralesional therapy with GM-CSF can increase the number and activation of dendritic cells,3 which are very efficient antigen-presenting cells that are capable of processing tumor antigens and crosstalk to lymphocytes. On the other hand, IL-2 administration can stimulate and activate tumor-infiltrating lymphocytes, which can result in the induction of cytotoxic T cells. Therefore, we felt that sequential intralesional administration of intralesional GM-CSF followed by IL-2 might complement one another, using the patients own tumor as a source for tumor antigens.. Exploratory Study. In an exploratory study in patients with dermal and subdermal metastatic melanoma, we explored the use of intra lesional therapy with low-dose ...
The respiratory tract is an attractive target organ for novel diagnostic and therapeutic applications with nano-sized carriers, but their immune effects and interactions with key resident antigen-presenting cells (APCs) such as dendritic cells (DCs) and alveolar macrophages (AMs) in different anatomical compartments remain poorly understood. Polystyrene particles ranging from 20 nm to 1,000 nm were instilled intranasally in BALB/c mice, and their interactions with APC populations in airways, lung parenchyma, and lung-draining lymph nodes (LDLNs) were examined after 2 and 24 hours by flow cytometry and confocal microscopy. In the main conducting airways and lung parenchyma, DC subpopulations preferentially captured 20-nm particles, compared with 1,000-nm particles that were transported to the LDLNs by migratory CD11b(low) DCs and that were observed in close proximity to CD3(+) T cells. Generally, the uptake of particles increased the expression of CD40 and CD86 in all DC populations, independent ...
CD4(+)CD25+ regulatory T (Treg) cells are pivotal for the maintenance of self-tolerance, and their adoptive transfer gives protection from autoimmune diseases and pathogenic alloresponses after solid organ or bone marrow transplantation in murine model systems. In vitro, human CD4(+)CD25+ Treg cells display phenotypic and functional characteristics similar to those of murine CD4(+)CD25+ Treg cells: namely, hyporesponsiveness to T-cell receptor (TCR) stimulation and suppression of CD25- T cells. Thus far, the detailed characterization and potential clinical application of human CD4(+)CD25+ Treg cells have been hampered by their paucity in peripheral blood and the lack of appropriate expansion protocols. Here we describe the up to 40 000-fold expansion of highly purified human CD4(+)CD25high T cells in vitro through the use of artificial antigen-presenting cells for repeated stimulation via CD3 and CD28 in the presence of high-dose interleukin 2 (IL-2). Expanded CD4(+)CD25high T cells were ...
The specific eradication of pathogenic T cells for the treatment of allograft rejections and autoimmune disorders without impairment of overall immune function is a fundamental goal. 41.5 times in bm1 mice. Our data reveal that PLGA-based great MPs are able of using up pathogenic Capital t cells particularly, which shows their restorative potential for dealing with allograft being rejected and autoimmune disorders. and conditions credited to the activity of cytotoxic Capital t cells, which can business lead to KAPC exhaustion or undesirable adjustments in cell-cell signaling [14, 15]. To circumvent the restrictions connected with the mobile character of KAPCs, great artificial antigen-presenting cells (KaAPCs) possess been founded by covalently coupling the HLA-A2-Ig and anti-Fas IgM monoclonal antibody (mAb) onto cell-sized permanent magnet beans, and had been able of using up antigen-specific Capital t cells [16]. We previously reported that latex bead-based KaAPCs could selectively deplete ...
Intrahepatic cell-derived, early IL-17 is definitely essential for initiating antigen-presenting cells in virus-like infection; nevertheless, the regulation and source of this IL-17 spike in the liver organ microenvironment are not well described. IL-17F additional uncovered that Lymphotoxin alpha antibody IL-17 signaling was vital for priming Testosterone levels cell replies in virus-like hepatitis. IL-17A oppressed IL-17F release and being injected with 3 109 pfu replication-deficient recombinant Advertisement having the LacZ gene (AdLacZ, bought from Vector Advancement Lab of Baylor University of Medication) as defined previously (25). Rodents had been being injected with 2 106 pfu lymphocytic choriomeningitis trojan (LCMV) Duplicate 13 (a kind present from Dr. Maria Salvato at the School of Baltimore) (37). Titration of LCMV was performed on Vero cell monolayers plated on 24-well plate designs, implemented by the virus-like quantification of immunological concentrate assay (38). The antibody ...
Remember, an allergen by definition is harmless, its the persons immune system response to it that is abnormal. It is often related to a genetic cause. According to Medscape:. The allergic reaction first requires sensitization to a specific allergen and occurs in genetically predisposed individuals. The allergen is either inhaled or ingested and is then processed by an antigen-presenting cell (APC), such as a dendritic cell, macrophage, or B-cell.[7,8]The antigen-presenting cells then migrate to lymph nodes, where they prime naïve TH cells that bear receptors for the specific antigen.2. So, genetics may play a role,3-5 but why do some family members have allergies and others do not? Furthermore, why do substances that trigger allergies vary in families? I discussed this in Part I in relationship to the chemicals found in skin care products mixing with essential oils. This is where environment may be at play in the concept of entopy, which is defined in a 2010 article in Clinical and ...
Plural - Dendritic cell A special type of cell that is a key regulator of the immune system, acting as a professional antigen-presenting cell (APC) capable of activating naïve T cells and stimulating the growth and differentiation of B cells. Dendritic cells are found, for example, in the lymph nodes and spleen. As an APC, a dendritic cell can retain antigen for long periods on its surface, present the antigen to a T or B cell and so influence their behavior. The word "dendritic" means "branched like a tree." It comes from the Greek "dendron" (tree). ...
T-bet is a Type-1 transcription factor that regulates the development of Type-1 T cell and Type-1 anti-tumor immunity. T-bet expression in Dendritic Cells (DC) is required for the ability of these antigen-presenting cells (APC) to prime Type-1-polarized T cell responses. Since T-bet is typically expressed by very low frequencies of activated DC (, 1%), we hypothesized that ectopic expression of T-bet as a consequence of recombinant adenovirus (rAd).T-bet transfection would yield a robust population of DC that were capable of (re)polarizing Type-1 anti-tumor T cell responses in vitro and in vivo. Indeed, human DC engineered to express high levels of T-bet strongly potentiated the development of Type-1 T cells from naïve T cells and concomitantly suppressed Th2 and Regulatory T cell (Treg) development in vitro. Interestingly, the superior Type-1 functionality of DC.Tbet seems to be largely independent of intrinsic Interleukin-12 (IL-12) production, as IL-12 neutralizing antibody failed to affect ...
TY - JOUR. T1 - Coadministration of antigen-conjugated and free CpG. T2 - Effects of in vitro and in vivo interactions in a murine model. AU - Herbáth, Melinda. AU - Szekeres, Zsuzsanna. AU - Kövesdi, Dorottya. AU - Papp, Krisztián. AU - Erdei, Anna. AU - Prechl, József. PY - 2014/8. Y1 - 2014/8. N2 - CpG oligodeoxynucleotides (CpG) are widely studied as promising adjuvants in vaccines against a range of diseases including infection, cancer or allergy. Conjugating antigen to CpG has been shown to potentiate the adjuvant effect via enhancing antigen uptake and danger signaling by the very same cell. In the present study, using biotinylated CpG and streptavidin as a model system, we demonstrate that CpG motif containing free and antigen-conjugated oligonucleotides do not compete in terms of cell activation via TLR9, but do compete for cellular uptake. Antigen-conjugated CpG enhances cellular association and uptake of the antigen by antigen-presenting cells (APC) and T cells. Free CpG ...
One strategy we are undertaking to advance this work is to characterize the antigen-presenting environment in pre- and post-natal life, with the focus on defining factors that dictate whether exposure to allergen in early life induces T cell sensitization or tolerance. The thinking is that in certain circumstances, T cell sensitization can occur in utero or in early post-natal life and that factors responsible for these circumstances have increased in the past 20 years. It has been proposed that this could explain the increased incidence of asthma and other inflammatory diseases. The challenge for scientists is to identify factors that control this process, with the ultimate goal of developing therapeutic strategies to reverse the progressive increase in disease. Our studies are focused on antigen-presenting cells such as dendritic cells (DCs) or macrophages, as they are known to direct the T cell responses to antigen throughout life, presumably including the pre- and post-natal period. In ...
Antigen Background HLA-DR is an MHC Class II antigen that maps to chromosome 6. It is a heterodimer composed of 2 non-covalently associated glycoproteins of about 35 kD (alpha, heavy) and 27 kD (beta, light).Both chains are comprised of two Ig-like domains and have transmembrane sequences and short cytoplasmic tails. It is reported to be expressed mainly on antigen-presenting cells (monocytes/macrophages and dendritic cells), B cells and some activated T cells. Expression has also been reported on thymic epithelial cells.. ...
Myeloid dendritic cells (DCs) are professional antigen-presenting cells critical for the orchestration of immunity and maintenance of self-tolerance. DC development and functions are tightly regulated by
Immunological synapses are organized cell-cell junctions between T lymphocytes and APCs composed of an adhesion ring, the peripheral supramolecular activation cluster (pSMAC), and a central T cell receptor cluster, the ...
Immunological synapses are organized cell-cell junctions between T lymphocytes and APCs composed of an adhesion ring, the peripheral supramolecular activation cluster (pSMAC), and a central T cell receptor cluster, the ...
By Jenny Gartshteyn. Faculty Peer Reviewed. Since the start of vaccination - weve eradicated smallpox and polio, saved college kids from meningitis, averted flu epidemics, and decreased the incidence of HPV-related cervical cancer … but can we teach our immune systems to actively fight existing cancer?. Heres the mechanism for an ideal anti-cancer vaccine:. With the growth and turnover of cancerous cells, cancer-specific tumor-associated antigens (TAAs) would be recognized and processed by professional antigen-presenting cells (APCs), such as dendritic cells and macrophages - which would …. Read more » ...