The major findings of this study are that oxidation-specific epitopes are detected in cells in the majority of atherosclerotic plaques but not in control coronary segments, and in general, cell-associated Ox5 epitopes do not appear to be present on apo B, which suggests that these oxidation-specific epitopes have formed on other proteins. Several lines of evidence suggest that the cell-associated, oxidation-specific epitopes recognized by antibody Ox5 are not on apo B of OxLDL. First, there is a lack of colocalized cell-associated staining for apo B. Previous studies33 37 showed that OxLDL retains immunoreactivity for apo B antibodies on Western blot and in ELISA. The present study demonstrates that internalized OxLDL retains immunoreactivity for the apo B antibody 9A in cultured macrophages. Thus, the observation that cells in human coronary arteries with positive Ox5 staining do not stain for 9A strongly suggests that these cell-associated Ox5 epitopes are not on apo B of OxLDL. Second, the ...
Retroviruses pack multiple genes into relatively small genomes by encoding several genes in the same genomic region with overlapping reading frames. Both sense and antisense HIV-1 transcripts contain open reading frames for known functional proteins as well as numerous alternative reading frames (ARFs). At least some ARFs have the potential to encode proteins of unknown function, and their antigenic properties can be considered as cryptic epitopes (CEs). To examine the extent of active immune response to virally encoded CEs, we analyzed human leukocyte antigen class I-associated polymorphisms in HIV-1 gag, pol, and nef genes from a large cohort of South Africans with chronic infection. In all, 391 CEs and 168 conventional epitopes were predicted, with the majority (307; 79%) of CEs derived from antisense transcripts. In further evaluation of CD8 T cell responses to a subset of the predicted CEs in patients with primary or chronic infection, both sense- and antisense-encoded CEs were immunogenic ...
TY - JOUR. T1 - Characterization of conformation-dependent prion protein epitopes. AU - Kang, Hae Eun. AU - Weng, Chu Chun. AU - Saijo, Eri. AU - Saylor, Vicki. AU - Bian, Jifeng. AU - Kim, Sehun. AU - Ramos, Laylaa. AU - Angers, Rachel. AU - Langenfeld, Katie. AU - Khaychuk, Vadim. AU - Calvi, Carla. AU - Bartz, Jason C.. AU - Hunter, Nora. AU - Telling, Glenn C.. PY - 2012/10/26. Y1 - 2012/10/26. N2 - Background: Despite structural reorganization during disease, conformational prion protein epitopes remain undefined. Results: We identify specific amino acids constituting novel conformational monoclonal antibody epitopes. Conclusion: Immunoreactivities of globular domain epitopes depend on maintenance of regional tertiary structure. Significance: Our studies address how denatured conformational epitopes remain functional, provide insights into normal and disease-related prion protein, and expand epitope tagging options.. AB - Background: Despite structural reorganization during disease, ...
In a recent study (51), we found that antibodies to all the neutralization epitopes on gp120, including the CD4bs, V2 and V3 loop, and 2G12 epitopes, neutralize HIV-1MN and Hx10 at least in part by blocking attachment of virus to cells. Indeed, the only antibody that did not interfere with HIV-cell attachment was the anti-gp41 MAb 2F5, which interacts with an epitope close to the transmembrane domain of the molecule. Taken together, the data of Ugolini et al. (51) and the present study suggest two plausible mechanisms for HIV-1 neutralization. The first invokes coating of the viral surface, which obstructs the close approach of virus and target cell membranes, as the principal mechanism. Individual epitopes play a minor role in this model because of the size of the antibody molecule relative to the proximity of the neutralization epitopes on gp120 to the CD4 binding region (Fig. 4). In this model, the high degree of glycosylation (about 50%) of gp120 reduces antibody accessibility to the protein ...
Pneumococcal surface protein A (PspA) and pneumococcal surface protein C (PspC) are important candidates for an alternative vaccine against pneumococcal infections. Since these antigens show variability, the use of variants that do not afford broad protection may lead to the selection of vaccine escape bacteria. Epitopes capable of inducing antibodies with broad cross-reactivities should thus be the preferred antigens. In this work, experiments using peptide arrays show that most linear epitopes recognized by antibodies induced in mice against different PspAs were located at the initial 44 amino acids of the mature protein and that antibodies against these linear epitopes did not confer protection against a lethal challenge. Conversely, linear epitopes recognized by antibodies to PspC included the consensus sequences involved in the interaction with human factor H and secretory immunoglobulin A (sIgA). Since linear epitopes of PspA were not protective, larger overlapping fragments containing 100 ...
Free resource for searching and exporting immune epitopes. Includes more than 95% of all published infectious disease, allergy, autoimmune, and transplant epitope data.
As a severe chronic metabolic disease and autoimmune disorder, type 1 diabetes (T1D) affects millions of people world-wide. Recent advances in antigen-based immunotherapy have provided a great opportunity for further treating T1D with a high degree of selectivity. It is reported that MHC class II I-Ag7 in the non-obese diabetic (NOD) mouse and human HLA-DQ8 are strongly linked to susceptibility to T1D. Thus, the identification of new I-Ag7 and HLA-DQ8 epitopes would be of great help to further experimental and biomedical manipulation efforts. In this study, a novel GPS-MBA (MHC Binding Analyzer) software package was developed for the prediction of I-Ag7 and HLA-DQ8 epitopes. Using experimentally identified epitopes as the training data sets, a previously developed GPS (Group-based Prediction System) algorithm was adopted and improved. By extensive evaluation and comparison, the GPS-MBA performance was found to be much better than other tools of this type. With this powerful tool, we predicted a number
Anti-HTT antibody epitopes and analysis by immunoblot.(A) Diagram representing antibody epitopes on human HTT protein (relative to GenBank accession CAD38447.1)
The promiscuous presentation of epitopes by similar HLA class I alleles holds promise for a universal T-cell-based HIV-1 vaccine. However, in some instances, cytotoxic T lymphocytes (CTL) restricted by HLA alleles with similar or identical binding motifs are known to target epitopes at different frequencies, with different functional avidities and with different apparent clinical outcomes. Such differences may be illuminated by the association of similar HLA alleles with distinctive escape pathways. Using a novel computational method featuring phylogenetically corrected odds ratios, we systematically analyzed differential patterns of immune escape across all optimally defined epitopes in Gag, Pol, and Nef in 2,126 HIV-1 clade C-infected adults. Overall, we identified 301 polymorphisms in 90 epitopes associated with HLA alleles belonging to shared supertypes. We detected differential escape in 37 of 38 epitopes restricted by more than one allele, which included 278 instances of differential escape at the
The CD4 molecules on the target macrophage and T cell are the primary receptors for the HIV-1 surface glycoprotein, gp120. In addition, chemokine receptors on the macrophage and T cell serve as co-receptors in the virus-cell interactions. An understanding of the mechanism of virus-cell interactions requires quantitative analyses of the structure-function correlations of the surface epitopes on gp120 which contains several constant (C) and variable (V) subdomains linked as C1-V1-V2-C2-V3-C3-V4-C4-V5-C5. The surface epitope inside the C4 loop is critical for CD4 binding. The epitopes inside the V1-V2 and V3 loops elicit HIV-1 neutralizing response as well as determine tropism, fusion, and infectivity of the virus. In absence of a high resolution structure of the entire gp120, we have adopted an alternative approach to analyzing the structural properties of these surface epitopes. For this purpose, we have combined theoretical and experimental techniques including sequence analysis, molecular modeling,
This epitope map visualizes all epitope residues associated with the mAb on to the structure of the DENV E protein. Epitope residues are depicted as spheres, colored according to domain, and with a size corresponding to the epitope resolution, for domain, peptide, and residue-level epitopes ...
Free resource for searching and exporting immune epitopes. Includes more than 95% of all published infectious disease, allergy, autoimmune, and transplant epitope data.
Polymorphism at the MHC locus enhances immune defense across the population by ensuring wide variation in the T cell response to infecting pathogens through presentation of a broad array of target epitopes (22, 23). This report has demonstrated another mechanism through which MHC polymorphism can diversify the immune response to an infecting pathogen. Thus, polymorphic MHC residues can markedly affect peptide binding conformation as well as MHC-peptide binding affinity, and this can have a major impact on the T cell response. Although previous studies have also demonstrated peptide structural alterations induced by MHC polymorphism (24, 25), none have shown that such changes can influence a peptide-specific immune response to this extent.. Our data demonstrate that a single residue polymorphism between HLA-B*3501 and HLA-B*3508 controls responsiveness to the APQP epitope through a mechanism unrelated to peptide-MHC binding efficiency/stability (Fig. 2). Furthermore, HLA-B*3501+, EBV-infected ...
RA is an HLA class II-associated autoimmune disease in which mucosal immunity, often resulting from interaction with oral or gut microbes or from inhaled antigens in the lung, is hypothesized to cause autoimmune phenomena leading to joint inflammation and damage. However, the factors linking mucosal immunity to autoimmunity in joints have been unclear. In this study in which HLA-DR-presented peptides were identified directly from patients synovial tissue or PBMCs, 2 previously unidentified self-antigens, GNS and FLNA, were shown to be targets of T and B cell responses in 52% and 56% of RA patients, respectively. Importantly, the GNS and FLNA HLA-DR-presented T cell epitopes have considerable sequence homology with Prevotella epitopes and with similar epitopes from several related gut commensals belonging to the same order, particularly in areas predicted to be in the HLA-DR-binding groove. Moreover, T cell responses to the corresponding microbial and self-peptides were strongly correlated, ...
soloMERs™ are superior to and differentiated from more traditional antibody platforms as they are pre-disposed to bind novel or cryptic epitopes ("canyon-binders"), seeking out pockets or grooves in protein targets. soloMERs can deliver the equivalent neutralising potency as antibodies, but from a protein only 9% their size.. Their simple modular formats express well in both prokaryotic and eukaryotic systems. soloMER re-formatting is "plug-n-play" with bi and tri-specificity and/or bi-paratopic potency achievable with a final molecular weight of only 25 - 35 kDa.. ...
Proper activation of DRs is critical in regulation of T cell development and function. However, the nature of functional receptors, which are expressed on T cells at stages characterized by resistance to the impact of FasL, TNF, and TRAIL, remains to be established. In this study, we have shown that engagement of distinct epitopes on CD99 induced rapid death signaling in the majority of immature T cell lines examined, apparently by a caspase-independent pathway. In contrast, only a few T cell lines were distinctly responsive to apoptosis-inducing anti-Fas and TRAIL. Differences between the Ad20/CD99-mediated death pathway and other novel nonclassical apoptotic pathways were also observed. Thus, our data suggest that CD99 may be a major DR used by the immune system to control T cells at stages before they acquire susceptibility to the impact of death-mediating cytokines of the TNF superfamily.. Previous studies have shown that activation of the CD99 domain specified by mAbs O662, L129, and DN16 ...
Now that we know what kinds of conditions need to be in place on the vaccine side of things for vaccine resistance to develop, how likely is it? How easy is it for the bacteria/viruses to evolve resistance? The short answer is, not very. When talking about diseases, antigens are the parts of viruses and bacteria that kick our immune systems into action. Theyre usually polysaccharides or proteins, and these polysaccharides and proteins have these things called epitopes. Its those epitopes that our antibodies bind to; they are what allow our immune system to latch onto and attack an invading bug. Antigens generally have multiple epitopes, and our antibodies are often able to act against more than one epitope. The more epitopes on an antigen that an antibody can bind to, the stronger the bond and the less chance the invader has of surviving. So even if we have a very narrowly designed vaccine that uses only a single protein from the target bacteria, for instance, the bacteria would need to change ...
Dall, P.; Hekele, A.; Ikenberg, H.; Göppinger, A.; Bauknecht, T.; Pfleiderer, A.; Moll, J.; Hofmann, M.; Ponta, H.; Herrlich, P ...
Dear Netters, Does anyone know of any software for the prediction of T-cell epitopes from peptide sequences? I have access to Mac, PC, VAX, SG & UNIX so the program format does not matter. Hope to hear from someone soon! Thanks, Brian Robertson Max-Planck-Institut fuer Biologie Abt. Infektionsbiologie D74 Tuebingen, FRG. Email robertson at mpib-tuebingen.mpg.de ...
Detection of nuclear epitopes of protein 4.1 by immunofluorescent light microscopy in WI38 cells. Cultured WI38 human fibroblasts were fixed in acetone for prob
A highly conserved cryptic epitope in the receptor-binding domains of SARS-CoV-2 and SARS-CoV Meng Yuan, et al., March 2020 The outbreak of COVID-19, which is caused by SARS-CoV-2 virus, continues to spread globally, but there is currently very little understanding of the epitopes on the…. ...
A young German company, founded in 2016, is specialised in the field of antigen recognition. The founder developed a method for the rapid and reliable characterisation of epitopes at the level of single amino acids and their allowed variations. The method identifies up to thousands of potential epitope/mimotope peptides combining even structural epitopes in single peptides to
|p|The Epitope Tag (Small Motif) Antibody Sampler Kit provides a convenient resource to detect small Epitope Tag fused protein by Western Blot. The DYKDDDDK tag, commonly referred to as Sigma®'s FLAG® Tag, is often used as a protein modification in order to simplify the labeling and detection of pro
Pk (V5) Epitope Tag (GKPIPNPLLGLDST), 1 mg. The V5 epitope tag is derived from a small epitope (Pk) present on the P and V proteins of the paramyxovirus of simian virus 5 (SV5).
Pk (V5) Epitope Tag (GKPIPNPLLGLDST), 0.1 mg. The V5 epitope tag is derived from a small epitope (Pk) present on the P and V proteins of the paramyxovirus of simian virus 5 (SV5).
Authors: AI Webb, MA Dunstone, WS Chen, MI Aguilar, QY Chen, H Jackson, L Chang, L Kjer-Nielsen, T Beddoe, J McCluskey, J Rossjohn, AW Purcell
Mouse Monoclonal Anti-DYKDDDDK Epitope Tag Antibody (29E4.G7) [DyLight 405]. Validated: WB, ELISA, IHC, IHC-P. Tested Reactivity: Human, Non-species specific. 100% Guaranteed.
Approximately 20% of human breast cancers are characterized by overexpression of the HER2 receptor tyrosine kinase molecule. Multiple anitbodies have been designed to specifically target HER2, and each is able to target the molecule at a different epitope.
Despite widespread uses of tetanus toxoid (TT) as a vaccine, model antigen and protein carrier, TT epitopes have been poorly characterized. Herein we defined the human CD4+ T cell epitope repertoire by reevaluation of previously described epitopes and evaluation of those derived from prediction of HLA Class II binding. Forty-seven epitopes were identified following in vitro TT stimulation, with 28 epitopes accounting for 90% of the total response. Despite this diverse range of epitopes, individual responses were associated with only a few immunodominant epitopes, with each donor responding on average to 3 epitopes. For the top 14 epitopes, HLA restriction could be inferred based on HLA typing of the responding donors. HLA binding predictions re-identified the vast majority of known epitopes, and identified 24 additional novel epitopes. With these epitopes, we created a TT epitope pool, which allowed us to characterize TT responses directly ex vivo using a cytokine-independent Activation Induced ...
Antigen-binding receptors on T lymphocytes and IgG antibodies with the same antigen-binding specificity as the T-cell receptors display shared or identical idiotypes. This was shown using a system where adult F1 hybrid rats between two inbred strains were inoculated with T lymphocytes from one parental strain. Such F1 hybrid rats produce antibodies directed against idiotypic determinants present on IgG alloantibodies, produced in the T donor genotype strain and with specificity for the alloantigens of the other parental strain. The idiotypic nature of the F1 antialloantibody serum against the parental alloantibodies was demonstrated both by indirect hemagglutination tests or by gel diffusion using alloantisera with different specificity as targets. Furthermore, the F1 anti-T-lymphocyte sera could be shown to contain antibodies against idiotypic parental T lymphocytes as well. This was shown by the capacity of the antisera, in the presence of complement, to wipe out the relevant parental T-cell ...
Two-site immunometric assays for multideterminant antigens are described in which the antigen is reacted with an immobilized monoclonal antibody directed against one antigen determinant and a second monoclonal antibody that is directed against a distinct antigenic determinant and is of a different class or subclass than the immobilized monoclonal antibody. The second monoclonal antibody is labeled in direct versions of the assay and is reacted with a labeled antibody against it in indirect versions of the assay. The immobilizing medium and classes (subclasses) of the antibodies may be selected so as to reduce the likelihood of nonspecific binding enhance sensitivity and/or permit signal amplification.
Autoimmunity is frequently involved in the pathogenesis of insulin-dependent diabetes, and viral infections have been implicated in some cases. We have investigated the possibility that islet cells and viruses share antigenic determinants with the result that antiviral antibodies would cross-react with islet cells. Antibody titers to Coxsackie B2, B3, B4, and B5, Influenza A and B, and mumps viruses were compared with islet cell antibody (ICA) titers in newly diagnosed insulin-dependent diabetic patients and in some diabetic patients followed prospectively for 1 yr postdiagnosis. Nondiabetic patients, with cultureproven Coxsackie B4 infections and large rises in Coxsackie B4 antibody titers, were evaluated for islet cell antibodies. No relationship between ICA and viral antibody titers was found either in diabetic or nondiabetic patients. We conclude that it is unlikely that islet cells and the viruses tested share antigenic determinants and other mechanisms relating viral infection and ...
Computational methods provide approaches to identify epitopes in protein Ags to help characterizing potential biomarkers identified by high-throughput genomic or proteomic experiments. PEPOP version 1.0 was developed as an antigenic or immunogenic peptide prediction tool. We have now improved this tool by implementing 32 new methods (PEPOP version 2.0) to guide the choice of peptides that mimic discontinuous epitopes and thus potentially able to replace the cognate protein Ag in its interaction with an Ab. In the present work, we describe these new methods and the benchmarking of their performances. Benchmarking was carried out by comparing the peptides predicted by the different methods and the corresponding epitopes determined by X-ray crystallography in a dataset of 75 Ag-Ab complexes. The Sensitivity (Se) and Positive Predictive Value (PPV) parameters were used to assess the performance of these methods. The results were compared to that of peptides obtained either by chance or by using the
We determined the antigenic specificity and protective immunogenicity of two chemically synthesized peptides of type 5 streptococcal M protein. The synthetic peptides, designated S-M5(1-20) and S-M5(20-40), represent the amino-terminal amino acid sequence of the native pepsin-extracted M5 molecule, which is known to contain at least one heart cross-reactive epitope. Initial studies showed that neither of the synthetic peptides was able to bind purified heart-reactive M5 antibodies. In addition, S-M5(1-20), but not S-M5(20-40), contained type-specific antigenic determinants as measured by enzyme-linked immunosorbent inhibition assays. When covalently linked to tetanus toxoid, S-M5(1-20), but not S-M5(20-40), evoked significant levels of type-specific, opsonic (and presumably protective) antibodies in rabbits without evoking heart cross-reactive antibodies. ...
We have identified six monoclonal antibodies (MAbs) mapping to both linear and conformation-dependent epitopes within the V2 region of the human immunodeficiency virus type 1 clone HXB10. Three of the MAbs (12b, 66c, and 66a) were able to neutralize the molecular clones HXB10 and HXB2, with titers in the range of 9.5 to 20.0 micrograms/ml. MAbs mapping to the crown of the V2 loop (12b, 60b, and 74) bound poorly to cell surface-expressed oligomeric gp120, suggesting an explanation for the poor or negligible neutralizing activity of MAbs to this region. In contrast, MAbs 12b and 60b demonstrated good reactivity with recombinant gp120 in an enzyme-linked immunosorbent assay format, suggesting differential epitope exposure between the recombinant and native forms of gp120. Cross-competition analysis of these MAbs and additional V1V2 MAbs for gp120 binding enabled us to assign the MAbs to six groups (A to F). Selection of neutralization escape mutants with MAbs 10/76b and 11/68b, belonging to nonoverlapping
CD8+ T cells have the potential to control HSV-2 infection. However, limited information has been available on CD8+ T cell epitopes or the functionality of antigen specific T cells during infection or following immunization with experimental vaccines. Peptide panels from HSV-2 proteins ICP27, VP22 and VP13/14 were selected from in silico predictions of binding to human HLA-A*0201 and mouse H-2Kd, Ld and Dd molecules. Nine previously uncharacterized CD8+ T cell epitopes were identified from HSV-2 infected BALB/c mice. HSV-2 specific peptide sequences stabilized HLA-A*02 surface expression with intermediate or high affinity binding. Peptide specific CD8+ human T cell lines from peripheral blood lymphocytes were generated from a HLA-A*02+ donor. High frequencies of peptide specific CD8+ T cell responses were elicited in mice by DNA vaccination with ICP27, VP22 and VP13/14, as demonstrated by CD107a mobilization. Vaccine driven T cell responses displayed a more focused immune response than those induced
The details of bibliography - Towards a vaccine for rheumatic fever: identification of a conserved target epitope on M protein of group a strepococci
The vast majority of therapeutic antibodies have a conformational or discontinuous epitope. Pepscan developed its proprietary CLIPSTM technology to construct constrained peptides which enable the 3D spatial conformation of these epitopes to be addressed. Our epitope mapping platform allows you to identify any type of epitope in a cost-effective and timely manner.. Pepscan developed this epitope mapping platform using solid support with a proprietary hydrogel matrix into which peptide sequences are directly synthesized using robust Fmoc peptide synthesis in a high density. This results in highly sensitive arrays and enables reliable detection of even the weakest binding signals. These immobilized peptide arrays are reusable and can be tested multiple times. This therefore permits screening of a series of antibodies or sera on a single array, making linear epitope mapping a fast and cost-effective option for best candidate selection and further development.. ...
Protein tyrosine kinases (PTKs) play pivotal roles in human cancer and are the targets of a major class of emerging anti-cancer drugs. In a single tumor, multiple PTKs are active and a substantial number are essential for maintaining the transformed phenotype. Though large numbers of phosphorylation sites have been mapped in cancer cells through mass spectrometry (MS), the identity of the specific kinases that phosphorylate these sites are with very few exceptions unknown. We propose to use emerging peptide microarray technology to identify consensus phosphorylation sequences for the entire set of human PTKs. We will generate a set of mammalian expression vectors producing every PTK fused to glutathione S-transferase. Each PTK will be affinity purified from a mammalian cell overexpression system and subjected to peptide microarray screening. These screens will reveal specific sequences preferred by each kinase at phosphorylation sites in their target substrates. We will use this data to mine ...
Journal of Immunology Research is a peer-reviewed, Open Access journal that provides a platform for scientists and clinicians working in different areas of immunology and therapy. The journal publishes research articles, review articles, as well as clinical studies related to classical immunology, molecular immunology, clinical immunology, cancer immunology, transplantation immunology, immune pathology, immunodeficiency, autoimmune diseases, immune disorders, and immunotherapy.
We recently discover a new immune escape mechanism that may help viruses escape from immune detection, which might compromise vaccine efficacy. Viruses that cause chronic infection in human contain higher numbers of T cell epitopes whose TCR-facing amino acids are identical to those of numerous peptides from the human proteome. We postulate that viruses that incorporate such human-like epitopes may exploit host tolerance to avoid or suppress effector responses. In order to predict these human-like epitopes, we developed an immunoinformatics tool, JanusMatrix.. Using JanusMatrix, we have identified T cell epitopes in H7N9 influenza HA protein that are highly conserved with human genome epitopes, and these epitopes possess low immunogenicity, activate natural Tregs and suppress bystander effector T cell responses in vitro. The human like T cell epitopes may contribute to the delayed, low titer of H7N9 hemagglutination inhibiting antibody responses and diminished seroconversion rates that have been ...
Background: Identification and validation of a targeted therapy for triple-negative breast cancer (TNBC), that is, breast cancers negative for oestrogen receptors, progesterone receptors and HER2 amplification, is currently one of the most urgent problems in breast cancer treatment. EGFR is one of the best-validated driver genes for TNBC. EGFR is normally activated following the release of ligands such as TGF alpha, mediated by the two MMP-like proteases ADAM (a disintegrin and metalloproteinase)-10 and ADAM-17. The aim of this study was to investigate the antitumour effects of a monoclonal antibody against ADAM-17 on an in vitro model of TNBC. Methods: We investigated an inhibitory cross-domain humanised monoclonal antibody targeting both the catalytic domain and the cysteine-rich domain of ADAM17-D1(A12) in the HCC1937 and HCC1143 cell lines. Results: D1(A12) was found to significantly inhibit the release of TGFa, and to decrease downstream EGFR-dependent cell signalling. D1(A12) treatment ...
Advances in the field of T cell immunology have contributed to the understanding that cross-reactivity is an intrinsic characteristic of the T cell receptor (TCR), and that each TCR can potentially interact with many different T cell epitopes. To better define the potential for TCR cross-reactivity between epitopes derived from the human genome, the human microbiome, and human pathogens, we developed a new immunoinformatics tool, JanusMatrix, that represents an extension of the validated T cell epitope mapping tool, EpiMatrix. Initial explorations, summarized in this synopsis, have uncovered what appear to be important differences in the TCR cross-reactivity of selected regulatory and effector T cell epitopes with other epitopes in the human genome, human microbiome, and selected human pathogens. In addition to exploring the T cell epitope relationships between human self, commensal and pathogen, JanusMatrix may also be useful to explore some aspects of heterologous immunity and to examine T cell
Monoclonal antibodies on MOUSE Tissue - posted in Immunology: Heres a question for the ages..Does anyone have a CLUE as to whether a protocol exists to use mouse monoclonal antibodies on mouse tissues without the outrageous background staining?? All suggestions are welcome. Thanx.
Epitope Mapping covers all the major methods for the identification and definition of epitopes. The Pepscan assay is used to define B cell epitopes and makes use of synthetic peptides but can only be used if the amino acid sequence is known. It can be adapted for the delineation of both helper T cells and cytotoxic T cells. The identification of combined B and T cell epitopes can also be achieved using synthetic peptides.
Characterization of human leukocyte antigen (HLA) class I restricted epitopes derived from viral pathogens is imperative for formulating therapeutic interventions, as well as for vaccine design and monitoring. Sensitive, easy and cost-effective assays that measure the frequency of antigen-specific T lymphocytes are crucial for evaluating and improving vaccines and therapies. This paper reviews the ELISPOT technique that allows for quantifying HIV-specific T lymphocytes at the single cell level from peripheral blood by detection of antigen-induced cytokine secretion. The assay can be used successfully to quantify T cell immune responses in humans infected with different pathogens and to assess T cell immunogenicity of vaccines in phase I/II and III clinical trials. This review focuses on the ELISPOT methodology and discusses how it can be standardized and potentially used by multiple international laboratories attached to clinical trial sites.
Autoantibodies targeting extracellular, rather than intracellular, domains of an antigen have a higher probability of being pathogenic by modulating receptor function, which can be studied in vitro and in vivo. However, since epitopes may vary between species, matching epitope targets between human autoantibodies and murine models is important for animal studies. For instance, the majority of patients with anti-MOG antibodies did not recognize conformational intact mMOG [56], whereas epitopes recognized by anti-NMDAR antibodies are similar between the two species [35], or at least share some cross-reactivity as in the case of anti-AQP4 antibodies [62, 134]. Longitudinal studies of autoimmune neurological disorders in humans are necessary to substantiate findings from animal models and determine whether the same mechanisms are relevant to human disease. Based on these results, decisions can be made as to whether the therapies that have proved effective in animal models are translatable to human ...
Peptides that are antigenic for T lymphocytes are ligands for two receptors, the class I or II glycoproteins that are encoded by genes in the major histocompatibility complex, and the idiotypic / chain T-cell antigen receptor1-9. That a peptide must bind to an MHC molecule to interact with a T-cell antigen receptor is the molecular basis of the MHC restriction of antigen-recognition by T lymphocytes10,11. In such a trimolecular interaction the amino-acid sequence of the peptide must specify the contact with both receptors: agretope residues bind to the MHC receptor and epitope residues bind to the T-cell antigen receptor12,13. From a compilation of known antigenic peptides, two algorithms have been proposed to predict antigenic sites in proteins. One algorithm uses linear motifs in the sequence14, whereas the other considers peptide conformation and predicts antigenicity for amphipathic -helices15,16. We report here that a systematic delimitation of an antigenic site precisely identifies a ...
Adoptive transfer of transplant donor or third party donor derived CMV-specific T cells (CMV-CTL) can effectively treat CMV infections in HSCT recipients. In clinical trials, infusion of partially matched third party CMV-CTLs, has demonstrated high response rates against persistent CMV infection. T-cells (TC) generated in vitro or directly selected in vivo demonstrate a striking preponderance of specificity for 1-2 immunodominant (ID) epitopes presented by specific HLA alleles. ID epitopes elicit higher TC functional activity in vivo, compared to sub-dominant (SD) epitopes. The relative clinical efficacy of TC directed against ID versus SD epitopes in vivo remains undefined. Agents augmenting activity of TC responsive to SD epitopes are unexplored. When these alleles are co-inherited in humans, epitopes of CMVpp65 presented by HLA A*02:01 are ID over HLA A*24:02 presented epitopes. We describe an in vivo model to assess efficacy of CMV-CTLs using colon carcinoma cells (coca)transduced to express ...
Tumour-specific mutations are ideal targets for cancer immunotherapy as they lack expression in healthy tissues and can potentially be recognized as neo-antigens by the mature T-cell repertoire.