Peptides containing a dominant T-cell epitope from red cell band 3 have in vivo immunomodulatory properties in NZB mice with autoimmune hemolytic anemia

Blood ◽  
2003 ◽  
Vol 102 (10) ◽  
pp. 3800-3806 ◽  
Author(s):  
Chia-Rui Shen ◽  
Abdel-Rahman Youssef ◽  
Anne Devine ◽  
Laura Bowie ◽  
Andrew M. Hall ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Hemolytic Anemia ◽  
Autoimmune Hemolytic Anemia ◽  
Cell Epitope ◽  
Band 3 ◽  
T Cell Epitope ◽  
Helper Epitope

Abstract The major target of the pathogenic red blood cell (RBC) autoantibodies in New Zealand black (NZB) mice is the anion channel protein band 3, and CD4+ T cells from NZB mice respond to band 3. Here, we demonstrate that a band 3 peptide 861-875, which is the predominant sequence recognized by NZB T cells in vitro, bears a dominant helper epitope able to modulate the autoimmune hemolyic anemia in vivo. The development of RBC-bound autoantibodies and anemia was accelerated in NZB mice injected with peptide 861-874, which is relatively insoluble, and inhalation of the peptide primed T cells for both peptide 861-874 and band 3 responses. By contrast, inhalation of a soluble analog (Glu861, Lys875) of peptide 861-874 deviated the autoimmune response toward a T helper-2 (Th2) profile, with marked increases in the ratio of interleukin-4 to interferon-γ produced by splenic T cells responding in vitro to either peptide 861-874 or band 3. Moreover, in mice that had received such treatment, the proportion of RBC-bound immunoglobulin G (IgG) molecules that were of the Th2-associated IgG1 isotype was also increased, and anemia was less severe. It is concluded that NZB autoimmune hemolytic anemia is helper dependent and that nasal administration of different peptides containing the dominant T-cell epitope can have potentially detrimental or beneficial effects on the disease. (Blood. 2003; 102:3800-3806)

scholarly journals T cell neoepitope discovery in colorectal cancer by high throughput profiling of somatic mutations in expressed genes

Gut ◽  
2015 ◽  
Vol 66 (3) ◽  
pp. 454-463 ◽  
Author(s):  
Daniele Mennonna ◽  
Cristina Maccalli ◽  
Michele C Romano ◽  
Claudio Garavaglia ◽  
Filippo Capocefalo ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
High Throughput ◽  
High Throughput Sequencing ◽  
Cell Epitope ◽  
Patient Specific ◽  
Cancer Genes ◽  
Healthy Donors

ObjectivePatient-specific (unique) tumour antigens, encoded by somatically mutated cancer genes, generate neoepitopes that are implicated in the induction of tumour-controlling T cell responses. Recent advancements in massive DNA sequencing combined with robust T cell epitope predictions have allowed their systematic identification in several malignancies.DesignWe undertook the identification of unique neoepitopes in colorectal cancers (CRCs) by using high-throughput sequencing of cDNAs expressed by standard cancer cell cultures, and by related cancer stem/initiating cells (CSCs) cultures, coupled with a reverse immunology approach not requiring human leukocyte antigen (HLA) allele-specific epitope predictions.ResultsSeveral unique mutated antigens of CRC, shared by standard cancer and related CSC cultures, were identified by this strategy. CD8+and CD4+T cells, either autologous to the patient or derived from HLA-matched healthy donors, were readily expanded in vitro by peptides spanning different cancer mutations and specifically recognised differentiated cancer cells and CSC cultures, expressing the mutations. Neoepitope-specific CD8+T cell frequency was also increased in a patient, compared with healthy donors, supporting the occurrence of clonal expansion in vivo.ConclusionsThese results provide a proof-of-concept approach for the identification of unique neoepitopes that are immunogenic in patients with CRC and can also target T cells against the most aggressive CSC component.

scholarly journals Immunogenicity of a Recombinant Influenza Virus Bearing Both the CD4+ and CD8+ T Cell Epitopes of Ovalbumin

2011 ◽  
Vol 2011 ◽  
pp. 1-7 ◽  
Author(s):  
Bruno Garulli ◽  
Giuseppina Di Mario ◽  
Ester Sciaraffia ◽  
Yoshihiro Kawaoka ◽  
Maria R. Castrucci
Keyword(s):  
T Cells ◽  
Influenza Virus ◽  
T Cell ◽  
Cell Epitope ◽  
Cd8 T Cell ◽  
Influenza Viruses ◽  
T Cell Epitope ◽  
T Cell Epitopes ◽  
Additional Tool

Recombinant influenza viruses that bear the single immunodominant CD8+ T cell epitopeOVA257−264or the CD4+ T cell epitopeOVA323−339of the model antigen ovalbumin (OVA) have been useful tools in immunology. Here, we generated a recombinant influenza virus,WSN-OVAI/II, that bears both OVA-specific CD8+ and CD4+ epitopes on its hemagglutinin molecule. Live and heat-inactivatedWSN-OVAI/IIviruses were efficiently presented by dendritic cellsin vitroto OT-I TCR transgenic CD8+ T cells and OT-II TCR transgenic CD4+ T cells.In vivo,WSN-OVAI/IIvirus was attenuated in virulence, highly immunogenic, and protected mice from B16-OVA tumor challenge in a prophylactic model of vaccination. Thus,WSN-OVAI/IIvirus represents an additional tool, along with OVA TCR transgenic mice, for further studies on T cell responses and may be of value in vaccine design.

Initial Identification of a Mouse Human Factor IX-Specific CD8+ T-Cell Epitope.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 5490-5490
Author(s):  
Brad E. Hoffman ◽  
Roland W. Herzog
Keyword(s):  
T Cells ◽  
T Cell ◽  
Catalytic Domain ◽  
Cell Epitope ◽  
Cd8 T Cell ◽  
Factor Ix ◽  
T Cell Epitope ◽  
Cell Responses ◽  
Ifn Γ

Abstract A significant complication associated with treatment of inherited protein deficiencies, such as hemophilia B, by gene replacement therapy is the potential for the activation of transgene specific B and T cells to the therapeutic protein, coagulation factor IX (F.IX). In addition to the potential for inhibitor formation as a result of MHC class II antigen presentation (CD4+ T cell-dependent activation of B cells, which may also be observed in conventional protein-based therapy), gene expression may lead to MHC class I presentation of F.IX-derived peptides to CD8+ T cells. Upon in vivo gene transfer, such immune responses to may elicit a cytotoxic T lymphocyte (CTL) response capable of destroying target cells that express the F.IX transgene product. Therefore, to better understand the role of F.IX-specific CD8+ T-cell responses, it is essential that MHC I-restricted CD8 T-cell epitopes be identified. Here, we used a peptide library consisting of 82 individual 15-mer peptides overlapping by ten residues that spans the complete human F.IX (hF.IX) protein to preliminarily identify a specific immunodominate CD8+ T-cell epitope. The peptides were pooled into groups, each containing 8–11 peptides to create a matrix of 18 pools, with each peptide represented in two pools. C3H/HeJ were immunized with 5×1010 vector genomes of E1/E3-deleted adenovirus expressing hF.IX (Ad-hF.IX) via intramuscular injection into the quadriceps. Nine days later, the harvested spleen and popliteal lymph node cells were pooled and evaluated for CD8+ T-cell responses by intracellular cytokine staining for IFN-γ after being stimulated for 5h with peptides or controls. The frequency of IFN-γ producing hF.IX-specific CD8+ T-cells was determined by flow cytometry. While 16 pools from Ad-hF.IX immunized C3H/HeJ mice showed no response above the frequency of mock-stimulated cells, lymphocytes from two overlapping pools demonstrated a ~2.5-fold increase in frequency of CD8+ IFN-γ+ cells. From these results we can conclude that peptide 74 (SGGPHVTEVEGTSFL) contains a CD8+ T cell epitope for C3H/HeJ mice (H-2k haplotype). Furthermore, splenocytes from naive mice failed to respond to any of the peptide pools. The amino acid sequence corresponding to peptide 74 is located within the catalytic domain of hF.IX. This finding is of particular interest, in that, we previously reported a peptide containing the immunodominate CD4+ T-cell epitope in C3H/HeJ is also located within the catalytic domain of hF.IX (Blood 108:408). The definitive identification of hF.IX-specific CD8+ epitopes will facilitate the evaluation of experimental gene therapy strategies in murine models by providing a reagent for in vitro stimulation of F.IX specific CD8+ lymphocytes. For example, we can now determine the efficiency of CD8+ T cell activation as a function of vector, route, and dose following in vivo gene transfer.

scholarly journals Inhibition of T cell and antibody responses to house dust mite allergen by inhalation of the dominant T cell epitope in naive and sensitized mice.

1993 ◽  
Vol 178 (5) ◽  
pp. 1783-1788 ◽  
Author(s):  
G F Hoyne ◽  
R E O'Hehir ◽  
D C Wraith ◽  
W R Thomas ◽  
J R Lamb
Keyword(s):  
Immune Response ◽  
T Cells ◽  
T Cell ◽  
Cell Epitope ◽  
Cell Recognition ◽  
T Cell Epitope ◽  
T Cell Recognition ◽  
Dust Mite ◽  
Der P 1

Antigen-specific CD4+ T cells play an important role in the allergic immune response to house dust mite (HDM) allergens in humans. The group 1 allergen of Dermatophagoides spp. is a major target antigen in both B and T cell recognition of HDM. In vitro studies have shown that the presentation of peptides to human T cells under appropriate conditions may lead to a state of specific nonresponsiveness. Therefore, to determine if peptides are able to modulate the function of allergen-reactive T cells in vivo, we have used a murine model of T cell recognition of the HDM allergen Der p 1. The results demonstrate that inhalation of low concentrations of peptide containing the major T cell epitope of Der p 1 (residues 111-139), induces tolerance in naive C57BL/6J mice such that they become profoundly unresponsive to an immunogenic challenge with the intact allergen. When restimulated in vitro with antigen, lymph node T cells isolated from tolerant mice secrete very low levels of interleukin 2, proliferative poorly, and are unable to provide cognate help to stimulate specific antibody production. Furthermore, intranasal peptide therapy was able to inhibit an ongoing immune response to the allergen in mice and this has potential implications in the development of allergen-based immunotherapy.

scholarly journals A Method for Individualizing the Prediction of Immunogenicity of Protein Vaccines and Biologic Therapeutics: Individualized T Cell Epitope Measure (iTEM)

2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Tobias Cohen ◽  
Leonard Moise ◽  
Matthew Ardito ◽  
William Martin ◽  
Anne S. De Groot
Keyword(s):  
Immune Response ◽  
T Cell ◽  
Cell Epitope ◽  
Protein Therapeutics ◽  
T Cell Response ◽  
In Vivo Studies ◽  
T Cell Epitope ◽  
Hla Binding

The promise of pharmacogenomics depends on advancing predictive medicine. To address this need in the area of immunology, we developed the individualized T cell epitope measure (iTEM) tool to estimate an individual's T cell response to a protein antigen based on HLA binding predictions. In this study, we validated prospective iTEM predictions using data from in vitro and in vivo studies. We used a mathematical formula that convertsDRB1∗allele binding predictions generated by EpiMatrix, an epitope-mapping tool, into an allele-specific scoring system. We then demonstrated that iTEM can be used to define an HLA binding threshold above which immune response is likely and below which immune response is likely to be absent. iTEM's predictive power was strongest when the immune response is focused, such as in subunit vaccination and administration of protein therapeutics. iTEM may be a useful tool for clinical trial design and preclinical evaluation of vaccines and protein therapeutics.

scholarly journals Both CD4+ and CD8+ T Cells Respond to Antigens Fused to Anthrax Lethal Toxin

2008 ◽  
Vol 76 (6) ◽  
pp. 2603-2611 ◽  
Author(s):  
Christine A. Shaw ◽  
Michael N. Starnbach
Keyword(s):  
T Cells ◽  
T Cell ◽  
Host Cell ◽  
Mhc Class I ◽  
Fusion Proteins ◽  
Lethal Factor ◽  
Cell Epitope ◽  
T Cell Epitope ◽  
Stimulation Of

ABSTRACT The lethal toxin produced by Bacillus anthracis is a bipartite toxin in which the first protein, protective antigen (PA), transports the second protein, lethal factor, across the host cell membrane. We have previously shown that CD8+ T-cell epitopes fused to a nontoxic derivative of lethal factor (LFn) are delivered into the host cell cytosol in a PA-dependent manner. Delivery of these antigens targets them to the intracellular major histocompatibility complex (MHC) class I processing and presentation pathway and leads to the stimulation of antigen-specific CD8+ T cells in vivo. In this report, we describe the generation and characterization of LFn fusion proteins that include not only a CD8+ T-cell epitope but also a CD4+ T-cell epitope. We first show that these fusion proteins induce antigen-specific CD4+ T-cell responses following incubation with dendritic cells in vitro or injection into mice. Stimulation of CD4+ T cells by LFn fusion proteins does not require PA but is enhanced by PA in vitro. We also show that a single LFn fusion protein and PA can deliver antigen to both the MHC class II and the MHC class I pathways, resulting in the simultaneous induction of antigen-specific CD4+ T cells and antigen-specific CD8+ T cells in the same mouse. These results suggest that this toxin delivery system is capable of stimulating protective immune responses where effective immunization requires stimulation of both classes of T cells.

scholarly journals Swine T-Cells and Specific Antibodies Evoked by Peptide Dendrimers Displaying Different FMDV T-Cell Epitopes

2021 ◽  
Vol 11 ◽  
Author(s):  
Patricia de León ◽  
Rodrigo Cañas-Arranz ◽  
Sira Defaus ◽  
Elisa Torres ◽  
Mar Forner ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
Cell Epitope ◽  
T Cell Epitope ◽  
T Cell Epitopes ◽  
B Cell Epitope ◽  
Mouth Disease Virus ◽  
Ifn Γ

Dendrimeric peptide constructs based on a lysine core that comprises both B- and T-cell epitopes of foot-and-mouth disease virus (FMDV) have proven a successful strategy for the development of FMD vaccines. Specifically, B2T dendrimers displaying two copies of the major type O FMDV antigenic B-cell epitope located on the virus capsid [VP1 (140–158)], covalently linked to a heterotypic T-cell epitope from either non-structural protein 3A [3A (21–35)] or 3D [3D (56–70)], named B2T-3A and B2T-3D, respectively, elicit high levels of neutralizing antibodies (nAbs) and IFN-γ-producing cells in pigs. To assess whether the inclusion and orientation of T-3A and T-3D T-cell epitopes in a single molecule could modulate immunogenicity, dendrimers with T epitopes juxtaposed in both possible orientations, i.e., constructs B2TT-3A3D and B2TT-3D3A, were made and tested in pigs. Both dendrimers elicited high nAbs titers that broadly neutralized type O FMDVs, although B2TT-3D3A did not respond to boosting, and induced lower IgGs titers, in particular IgG2, than B2TT-3A3D. Pigs immunized with B2, a control dendrimer displaying two B-cell epitope copies and no T-cell epitope, gave no nABs, confirming T-3A and T-3D as T helper epitopes. The T-3D peptide was found to be an immunodominant, as it produced more IFN-γ expressing cells than T-3A in the in vitro recall assay. Besides, in pigs immunized with the different dendrimeric peptides, CD4+ T-cells were the major subset contributing to IFN-γ expression upon in vitro recall, and depletion of CD4+ cells from PBMCs abolished the production of this cytokine. Most CD4+IFN-γ+ cells showed a memory (CD4+2E3−) and a multifunctional phenotype, as they expressed both IFN-γ and TNF-α, suggesting that the peptides induced a potent Th1 pro-inflammatory response. Furthermore, not only the presence, but also the orientation of T-cell epitopes influenced the T-cell response, as B2TT-3D3A and B2 groups had fewer cells expressing both cytokines. These results help understand how B2T-type dendrimers triggers T-cell populations, highlighting their potential as next-generation FMD vaccines.

scholarly journals A Heterologous Helper T-Cell Epitope Enhances the Immunogenicity of a Multiple-Antigenic-Peptide Vaccine Targeting the Cryptic Loop-Neutralizing Determinant of Bacillus anthracis Protective Antigen

2009 ◽  
Vol 77 (12) ◽  
pp. 5509-5518 ◽  
Author(s):  
Jon Oscherwitz ◽  
Fen Yu ◽  
Kemp B. Cease
Keyword(s):  
T Cell ◽  
B Cell ◽  
Protective Antigen ◽  
Cell Epitope ◽  
Antibody Responses ◽  
T Cell Epitope ◽  
Helper T Cell ◽  
Multiple Antigenic Peptide ◽  
Helper Epitope

ABSTRACT We previously showed that a multiple antigenic peptide (MAP) displaying amino acids (aa) 305 to 319 from the 2β2-2β3 loop of protective antigen (PA) can elicit high-titered antibody that neutralizes lethal toxin (LeTx) in vitro and that this loop-neutralizing determinant (LND) specificity is absent in PA-immune rabbits. Some immune rabbits were, however, nonresponders to the MAP. We hypothesized that the immunogen elicited suboptimal major histocompatibility complex (MHC) class II-restricted T-cell help and that introduction of a functional helper T-cell epitope would increase MHC-restricted responsiveness and the magnitude and affinity of the antibody responses. In the current study, we characterized the T- and B-cell responses to LND peptides in mice, then designed second-generation MAP immunogens for eliciting LND-specific immunity, and tested them in rabbits. The 305-319 sequence was devoid of helper T-cell epitopes in three strains of mice; however, a T-B peptide comprising aa 305 to 319, colinearly synthesized with the P30 helper epitope of tetanus toxin, elicited robust LeTx-neutralizing immunity in mice. T-B MAPs displaying B-cell epitopes 304 to 319 (MAP304) or 305 to 319 (MAP305) elicited high-titer, durable antibody responses in rabbits which exhibited potent neutralization of LeTx in vitro. All MAP304-immune rabbits demonstrated neutralization titers exceeding that of hyperimmune sera of rabbits immunized with PA in Freund's adjuvant, with peak neutralization titers 23-, 6-, and 3-fold higher than that of the PA antiserum. Overall, immunization with MAPs containing the P30 epitope elicited higher antibody and toxin neutralization titers and peptide-specific affinity than immunization with an LND MAP lacking a helper epitope. P30-containing MAP304 represents a promising LND-specific vaccine for anthrax.

Sign in / Sign up

Export Citation Format

Share Document