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1.
Sylvie Rusakiewicz Alejandro Madrigal Paul Travers Anthony I. Dodi 《Cancer immunology, immunotherapy : CII》2009,58(9):1449-1457
The BCR/ABL p210 fusion protein has long been considered an ideal target antigen for the development of immunotherapeutic
strategies in chronic myeloid leukaemia (CML) due to its central role in malignant transformation and to its unique novel
amino acid sequence solely expressed in leukaemia cells. However, the feasibility to expand BCR-ABL-specific T cells remains
still controversial. Using BCR/ABL peptide/MHC tetramers, significantly higher frequencies of tetramer positive cells were
detected in the peripheral blood of HLA-A*0301 (mean 0.38%) and HLA-B*0801 (mean 0.28%) CML patients than in healthy donors
(P = 0.0025 and 0.0026, respectively). However, following stimulation with autologous peptide-pulsed DCs, BCR/ABL-specific T
cells were only expanded from some healthy donors, suggesting that CML patients may have a specific immune deficit with respect
to the BCR/ABL antigen.
Professor A. I. Dodi passed away recently.
This paper is an original contribution from the meeting which took place 28–29 May 2008 in Nottingham, UK, celebrating the
contribution of Prof. A. I. “Tony” Dodi (29 January 2008) to the EU project “Network for the identification and validation
of antigens and biomarkers in cancer and their application in clinical tumour immunology (ENACT)”. 相似文献
2.
Hiroya Kobayashi Shoji Kimura Naoko Aoki Keisuke Sato Esteban Celis Makoto Katagiri 《Immunogenetics》2001,53(8):626-633
It is generally accepted that as the result of positive thymic selection, CD8-expressing T cells recognize peptide antigens presented in the context of MHC class I molecules and CD4-expressing T cells interact with peptide antigens presented by MHC class II molecules. Here we report the generation of TCRalpha/beta(+), CD3(+), CD4(+), CD8(-), MHC class I-restricted alloreactive T-cell clones which were induced using peripheral blood mononuclear cells from healthy individuals following in vitro stimulation with transporter associated with antigen processing (TAP)-deficient cell lines T2. The CD4(+) T-cell clones showed an HLA-A2.1-specific proliferative response against T2 cells which was inhibited by anti-CD3 and anti-CD4 monoclonal antibodies. These results suggest that interaction of the TCR with peptide-bound HLA class I molecules contributes to antigen-specific activation of these co-receptor-mismatched T-cell clones. Antigen recognition by alloreactive MHC class I-restricted CD4(+) T cells was inhibited by removing peptides bound to HLA molecules on T2 cells suggesting that the alloreactive CD4(+) T cells recognize peptides that bind in a TAP-independent manner to HLA-A2 molecules. The existence of such MHC class I-restricted CD4(+) T cells which can recognize HLA-A2 molecules in the absence of TAP function may provide a basis for the development of immunotherapy against TAP-deficient tumor variants which would be tolerant to immunosurveillance by conventional MHC class I-restricted cytotoxic lymphocytes. 相似文献
3.
XiuFang Weng ZhiHui Liang XiaoLing Lu MaoHua Zhong ShengJun Lu CaiE Zhang Jing Deng XiongWen Wu FeiLi Gong 《中国科学:生命科学英文版》2007,50(2):203-211
The role of the bound peptide in alloreactive T-cell recognition is controversial, ranging from pep-tide-independent to peptide-specific recognition of alloreactive T-cells. The aim of this study is to find the evidence that there exist peptide/MHC complex (pMHC)-specific CTLs among alloreactive T cells generated with long-term mixed lymphocytes culture (LTMLC). A single pMHC was manipulated by loading the TAP-defective, HLA-A2 expressing T2 cells with a viral peptide (LMP2A426-434) or a self-peptide (Tyr369-377). The PBLs samples from 4 HLA-A2 positive (HLA-A2 ve) and 4 HLA-A2 negative (HLA-A2-ve) donors were included in this study. The HLA-A2 ve PBL co-cultured with the LMP2A426-434 pulsed T2 (T2/LMP) stands for the nominal T-cell response to a viral antigen, and the HLA-A2-ve PBLs co-cultured with the Tyr369-377 pulsed T2 (T2/Tyr) for alloreactive T-cell response to an allogeneic antigen. The specificity of the expanded CTLs after the LTMLC was detected by their specific cytotoxicity and binding ability to specific pMHC-tetramer. An HLA-A2 restricted, HIV peptide (Gag77-85)was included for control. The cultural bulk of HLA-A2 ve PBLs with the T2/LMP showed an elevated specific cytotoxicity against the T2/LMP compared to that against the T2/HIV (26.52%±3.72% vs 7.01%±0.87%, P<0.001), and an increased frequency of binding to LMP-tetramer compared to that binding to HIV-tetramer (0.98%±0.33% vs 0.05%±0.01%, P=0.0014). The cultural bulk of HLA-A2-ve PBLs with the T2/Tyr showed a more active cytotoxicity against the T2/Tyr than that against T2/HIV (28.07%±2.58% vs 6.87%±0.01 %, P<0.001), and a higher frequency of binding to the Tyr-tetramer than that binding to the HIV-tetramer (0.88%±0.3% vs 0.06%±0.03%, P=0.0018). Our results indicate that the LTMLC is able to expand the viral antigen-specific CTLs as well as allogeneic antigen-specific CTLs. A relatively large proportion of alloreactive CTLs should be pMHC-specific, i.e., the specificity of the alloreactive lines depends on both the bound peptide and the allotype of MHC. Our observations support the hypothesis that the cumulative effect of T cells specific to each peptide epitope could account for the strength and diversity of the alloresponse. The method using manipulated pMHC and the LTMLC to generate pMHC-specific, alloreactive CTLs is of potential importance for adoptive T-cell immunotherapy. 相似文献
4.
Cullen CM Jameson SC DeLay M Cottrell C Becken ET Choi E Hirsch R 《Cellular immunology》1999,192(1):54-62
Activation of antigen-specific T cell clones in vivo might be possible by generating soluble MHC molecules; however, such molecules do not induce effective T cell responses unless cross-linked. As a first step in generating a soluble MHC molecule that could function as an antigen-specific immunostimulant, the extracellular domains of the murine H-2Kb MHC class I molecule were fused to the constant domains of a murine IgG1 heavy chain, resulting in a divalent molecule with both a TCR-reactive and an Fc receptor (FcR)-reactive moiety. The fusion protein can be loaded with peptide and can induce T cell activation in a peptide-specific, MHC-restricted manner following immobilization on plastic wells or following cross-linking by FcR+ spleen cells. The fusion protein induces partial T cell activation in vivo in a mouse transgenic for a TCR restricted to H-2Kb. This fusion protein molecule may be useful to study peptide-MHC interactions and may provide a strategy for boosting in vivo antigen-specific T cell responses, such as to viral or tumor antigens. 相似文献
5.
Voelkl S Moore TV Rehli M Nishimura MI Mackensen A Fischer K 《Cancer immunology, immunotherapy : CII》2009,58(5):709-718
The immune attack against malignant tumors require the concerted action of CD8+ cytotoxic T lymphocytes (CTL) as well as CD4+ T helper cells. The contribution of T cell receptor (TCR) αβ+ CD4− CD8− double-negative (DN) T cells to anti-tumor immune responses is widely unknown. In previous studies, we have demonstrated
that DN T cells with a broad TCR repertoire are present in humans in the peripheral blood and the lymph nodes of healthy individuals.
Here, we characterize a human DN T cell clone (T4H2) recognizing an HLA-A2-restricted melanoma-associated antigenic gp100-peptide
isolated from the peripheral blood of a melanoma patient. Antigen recognition by the T4H2 DN clone resulted in specific secretion
of IFN-γ and TNF. Although lacking the CD8 molecule the gp100-specifc DN T cell clone was able to confer antigen-specific
cytotoxicity against gp100-loaded target cells as well as HLA-A2+ gp100 expressing melanoma cells. The cytotoxic capacity was found to be perforin/granzymeB-dependent. Together, these data
indicate that functionally active antigen-specific DN T cells recognizing MHC class I-restricted tumor-associated antigen
(TAA) may contribute to anti-tumor immunity in vivo.
A. Mackensen and K. Fischer contributed equally to this work and should be considered joint senior authors. This work was
supported by the Deutsche Forschungsgemeinschaft (MA 1351/5-1, KFO 146) and NIH grants CA90873, CA102280, 104947 (MIN).
Companion paper: “Relationship between CD8-dependent antigen recognition, T cell functional avidity, and tumor cell recognition”
by Tamson V. Moore et al. doi: . 相似文献
6.
Pedersen LE Harndahl M Rasmussen M Lamberth K Golde WT Lund O Nielsen M Buus S 《Immunogenetics》2011,63(12):821-834
In all vertebrate animals, CD8+ cytotoxic T lymphocytes (CTLs) are controlled by major histocompatibility complex class I (MHC-I) molecules. These are highly
polymorphic peptide receptors selecting and presenting endogenously derived epitopes to circulating CTLs. The polymorphism
of the MHC effectively individualizes the immune response of each member of the species. We have recently developed efficient
methods to generate recombinant human MHC-I (also known as human leukocyte antigen class I, HLA-I) molecules, accompanying
peptide-binding assays and predictors, and HLA tetramers for specific CTL staining and manipulation. This has enabled a complete
mapping of all HLA-I specificities (“the Human MHC Project”). Here, we demonstrate that these approaches can be applied to
other species. We systematically transferred domains of the frequently expressed swine MHC-I molecule, SLA-1*0401, onto a
HLA-I molecule (HLA-A*11:01), thereby generating recombinant human/swine chimeric MHC-I molecules as well as the intact SLA-1*0401
molecule. Biochemical peptide-binding assays and positional scanning combinatorial peptide libraries were used to analyze
the peptide-binding motifs of these molecules. A pan-specific predictor of peptide–MHC-I binding, NetMHCpan, which was originally developed to cover the binding specificities of all known HLA-I molecules, was successfully used to
predict the specificities of the SLA-1*0401 molecule as well as the porcine/human chimeric MHC-I molecules. These data indicate
that it is possible to extend the biochemical and bioinformatics tools of the Human MHC Project to other vertebrate species. 相似文献
7.
Investigation of peptide involvement in T cell allorecognition using recombinant HLA class I multimers 总被引:2,自引:0,他引:2
Whitelegg AM Oosten LE Jordan S Kester M van Halteren AG Madrigal JA Goulmy E Barber LD 《Journal of immunology (Baltimore, Md. : 1950)》2005,175(3):1706-1714
Alloreactive T cells are involved in injurious graft rejection and graft-vs-host disease. However, they can also evoke beneficial responses to tumor Ags restricted by foreign MHC molecules. Manipulation of these alloreactivities requires information on the basis of T cell allorecognition. The vigorous T cell response to foreign MHC molecules may arise from peptide-independent recognition of polymorphic residues of foreign MHC molecules or peptide-specific recognition of novel peptides presented by foreign MHC molecules. We investigated CD8+ T cell allorecognition using recombinant HLA class I/peptide complexes. Peptide-specific allorecognition was examined using tetramers of HLA-A*0201 representing five peptides derived from ubiquitously expressed self-proteins that are known to bind endogenously to HLA-A*0201. Distinct subsets of CD8+ T cells specific for each HLA-A*0201/peptide combination were detected within four in vitro-stimulated T cell populations specific for foreign HLA-A*0201. Peptide-independent allorecognition was investigated using artificial Ag-presenting constructs (aAPCs) coated with CD54, CD80, and functional densities of a single HLA-A*0201/peptide combination for four different peptides. None of the four T cell populations specific for foreign HLA-A*0201 were stimulated by the aAPCs, whereas they did produce IFN-gamma upon stimulation with cells naturally expressing HLA-A*0201. Thus, aAPCs did not stimulate putative peptide-independent allorestricted T cells. The results show that these alloreactive populations comprise subsets of T cells, each specific for a self-peptide presented by foreign class I molecules, with no evidence of peptide-independent components. 相似文献
8.
Eddie A. James Rebecca LaFond Ivana Durinovic-Bello William Kwok 《Journal of visualized experiments : JoVE》2009,(25)
Major histocompatibility complex (MHC) class II tetramers allow the direct visualization of antigen specific CD4+ T cells by flow cytometry. This method relies on the highly specific interaction between peptide loaded MHC and the corresponding T-cell receptor. While the affinity of a single MHC/peptide molecule is low, cross-linking MHC/peptide complexes with streptavidin increases the avidity of the interaction, enabling their use as staining reagents. Because of the relatively low frequencies of CD4+ T cells (~1 in 300,000 for a single specificity) this assay utilizes an in vitro amplification step to increase its threshold of detection. Mononuclear cells are purified from peripheral blood by Ficoll underlay. CD4+ cells are then separated by negative selection using biotinylated antibody cocktail and anti-biotin labeled magnetic beads. Using adherent cells from the CD4- cell fraction as antigen presenting cells, CD4+ T cells are expanded in media by adding an antigenic peptide and IL-2. The expanded cells are stained with the corresponding class II tetramer by incubating at 37 C for one hour and subsequently stained using surface antibodies such as anti-CD4, anti-CD3, and anti-CD25. After labeling, the cells can be directly analyzed by flow cytometry. The tetramer positive cells typically form a distinct population among the expanded CD4+ cells. Tetramer positive cells are usually CD25+ and often CD4 high. Because the level of background tetramer staining can vary, positive staining results should always be compared to the staining of the same cells with an irrelevant tetramer. Multiple variations of this basic assay are possible. Tetramer positive cells may be sorted for further phenotypic analysis, inclusion in ELISPOT or proliferation assays, or other secondary assays. Several groups have also demonstrated co-staining using tetramers and either anti-cytokine or anti-FoxP3 antibodies. Open in a separate windowClick here to view.(85M, flv) 相似文献
9.
Brian M. Olson Thomas P. Frye Laura E. Johnson Lawrence Fong Keith L. Knutson Mary L. Disis Douglas G. McNeel 《Cancer immunology, immunotherapy : CII》2010,59(6):943-953
Prostatic acid phosphatase (PAP) has been investigated as the target of several antigen-specific anti-prostate tumor vaccines.
The goal of antigen-specific active immunotherapies targeting PAP would ideally be to elicit PAP-specific CD8+ effector T
cells. The identification of PAP-specific CD8+ T-cell epitopes should provide a means of monitoring the immunological efficacy
of vaccines targeting PAP, and these epitopes might themselves be developed as vaccine antigens. In the current report, we
hypothesized that PAP-specific epitopes might be identified by direct identification of pre-existing CD8+ T cells specific
for HLA-A2-restricted peptides derived from PAP in the blood of HLA-A2-expressing individuals. 11 nonamer peptides derived
from the amino acid sequence of PAP were used as stimulator antigens in functional ELISPOT assays with peripheral blood mononuclear
cells from 20 HLA-A2+ patients with prostate cancer or ten healthy blood donors. Peptide-specific T cells were frequently
identified in both groups for three of the peptides, p18–26, p112–120, and p135–143. CD8+ T-cell clones specific for three
peptides, p18–26, p112–120, and p299–307, confirmed that these are HLA-A2-restricted T-cell epitopes. Moreover, HLA-A2 transgenic
mice immunized with a DNA vaccine encoding PAP developed epitope-specific responses for one or more of these three peptide
epitopes. We propose that this method to first identify epitopes for which there are pre-existing epitope-specific T cells
could be used to prioritize MHC class I-specific epitopes for other antigens. In addition, we propose that the epitopes identified
here could be used to monitor immune responses in HLA-A2+ patients receiving vaccines targeting PAP to identify potentially
therapeutic immune responses. 相似文献
10.
Moore TV Lyons GE Brasic N Roszkowski JJ Voelkl S Mackensen A Kast WM Le Poole IC Nishimura MI 《Cancer immunology, immunotherapy : CII》2009,58(5):719-728
Effective immunotherapy using T cell receptor (TCR) gene-modified T cells requires an understanding of the relationship between
TCR affinity and functional avidity of T cells. In this study, we evaluate the relative affinity of two TCRs isolated from
HLA-A2-restricted, gp100-reactive T cell clones with extremely high functional avidity. Furthermore, one of these T cell clones,
was CD4−CD8− indicating that antigen recognition by this clone was CD8 independent. However, when these TCRs were expressed in CD8− Jurkat cells, the resulting Jurkat cells recognized gp100:209–217 peptide loaded T2 cells and had high functional avidity,
but could not recognize HLA-A2+ melanoma cells expressing gp100. Tumor cell recognition by Jurkat cells expressing these TCRs could not be induced by exogenously
loading the tumor cells with the native gp100:209–217 peptide. These results indicate that functional avidity of a T cell
does not necessarily correlate with TCR affinity and CD8-independent antigen recognition by a T cell does not always mean
its TCR will transfer CD8-independence to other effector cells. The implications of these findings are that T cells can modulate
their functional avidity independent of the affinity of their TCRs.
Companion Paper: “Characterization of MHC class-I restricted TCRαβ+ CD4− CD8− double negative T cells recognizing the gp100 antigen from a melanoma patient after gp100 vaccination” by Simon Voelkl, Tamson
V. Moore, Michael Rehli, Michael I. Nishimura, Andreas Mackensen, and Karin Fischer. doi:. 相似文献
11.
Spontaneous T cell responses to melanoma differentiation antigens from melanoma patients and healthy subjects 总被引:2,自引:0,他引:2
Qiyuan Chen Heather Jackson Peter Gibbs Ian D. Davis Joseph Trapani Jonathan Cebon 《Cancer immunology, immunotherapy : CII》1998,47(4):191-197
The spontaneous cytotoxic T cell responses to melanoma differentiation antigens and influenza matrix peptide were compared
in 20 HLA-A2+ melanoma patients and 17 healthy A2+ individuals. Cytotoxic T lymphocyte (CTL) responses were determined by mixed lymphocyte peptide culture (MLPC) involving
two stimulations of unfractionated peripheral blood lymphocytes (PBLs) with peptide in vitro. CTL responses to Melan-A 9-mer
(amino acids 27–35, AAGIGILTV) peptide were detected in 4 out of 16 normal individuals, but in none of the melanoma patients.
CTL specific for influenza matrix peptide were frequently found in both normal individuals and melanoma patients, suggesting
that generalized immuno-suppression was not responsible for this difference. No significant responses were observed in either
normal individuals or melanoma patients to Melan-A 10-mer (26–35, EAAGIGILTV), two gp100 epitopes (280–288, YLEPGPVTA; 457–466,
LLDGTATLRL) and two tyrosinase epitopes (1–9, MLLAVLYCL; 368–376, YMDGMSQV). Melan-A (27–35)-specific CTL cells generated
by normal individuals and melanoma patients recognized both synthetic peptide-pulsed T2 cells and two HLA-A2+, Melan-A+ melanoma cell lines (ME272, LAR1) in an antigen-specific, MHC class I restricted manner. T cells generated against Melan-A
9-mer were also able to recognize Melan-A 10-mer-pulsed target cells. Spontaneous CTL responses to Melan-A 9-mer from three
known responder normal individuals were further evaluated over a prolonged time course (6–11 months). All 3 subjects demonstrated
specific Melan-A 9-mer responses throughout the study period, although lytic activity fluctuated over time for a given individual.
We found the MLPC assay to be reliable and easy to perform for monitoring T cell responses, although it may still not be sufficiently
sensitive to detect low numbers of precursor T cells.
Received: 21 May 1998 / Accepted: 23 July 1998 相似文献
12.
Zhang HG Chen HS Peng JR Shang XY Zhang J Xing Q Pang XW Qin LL Fei R Mei MH Leng XS Chen WF 《Cancer immunology, immunotherapy : CII》2007,56(12):1945-1954
The MAGE-A3 protein, one of the promising tumor antigens for immunotherapy, is highly expressed in human hepatocellular carcinoma
(HCC). In this study, we estimated the specific CD8+ T cell immune response to MAGE-A3 p271–279 peptide (M3271) in the peripheral blood of HCC patients without antigen vaccination in order to evaluate its immunotherapeutic potential
in these patients. After expansion in vitro, the functional IFN-γ producing M3271 specific CD8+ T cells were detected in 30.8% (8/26) of HLA-A2+MAGE-A3+ HCC patients. The effector CD8+ T cells could release cytotoxic molecules of granzyme B and perforin after restimulation with natural HLA-A2+MAGE-A3+ HCC cell lines in the samples tested. The functional supertype of HLA-A2 in the presentation of HLA-A*0201 restricted M3271 peptide has been identified in the Chinese HCC patients of Han ethnicity, that widely expanded the applicability of this
tumor peptide vaccine in Chinese HCC patients. Thus, the functionally detectable pre-existence of M3271-specific CD8+ T cells in HCC patients makes M3271 a potential target for immunotherapy in these patients. The responsive CD8+ T cells to both NY-ESO-1 and MAGE-A3 antigens provide a rationale for the application of a bivalent vaccine in HCC patients
with tumors expressing both antigens.
H-G Zhang, H-S Chen, and J-R Peng are contributed equally to this paper. 相似文献
13.
Dorota Hoja-Łukowicz Małgorzata Przybyło Ewa Pocheć Anna Drabik Jerzy Silberring Marcelina Kremser Dirk Schadendorf Piotr Laidler Anna Lityńska 《Cancer immunology, immunotherapy : CII》2009,58(9):1471-1480
Nucleolin is multifunctional protein mainly present in nucleoli but also detected in cytoplasm and plasma membranes. Extranuclear
nucleolin differs from the nuclear form by its glycosylation. Studies on expression of nucleolin in breast cancer suggest
a possible association to the metastatic cascade. In the present study, Vicia villosa lectin (VVL) precipitation followed by subsequent polyacrylamide gel electrophoresis and mass spectrometry analysis demonstrates
nucleolin as a VVL-positive glycoprotein expressed in melanoma. The presence of VVL-positive nucleolin in the melanoma cell
membrane and cytoplasm was confirmed by confocal microscopy. Using bioinformatic peptide prediction programs, nucleolin was
shown to contain multiple possible MHC class-I binding peptides in its sequence which makes nucleolin an interesting melanoma
marker and target for immunodiagnostic and possibly therapeutic purposes.
This paper is an original contribution from the meeting which took place on 28–and 29 May, 2008, in Nottingham, UK, celebrating
the contribution of Professor I.A. “Tony” Dodi (+29.1.2008) to the EU project “Network for the identification and validation
of antigens and biomarkers in cancer and their application in clinical tumour immunology (ENACT)”. 相似文献
14.
Iero M Squarcina P Romero P Guillaume P Scarselli E Cerino R Carrabba M Toutirais O Parmiani G Rivoltini L 《Cancer immunology, immunotherapy : CII》2007,56(12):1979-1991
The use of “altered peptide ligands” (APL), epitopes designed for exerting increased immunogenicity as compared with native
determinants, represents nowadays one of the most utilized strategies for overcoming immune tolerance to self-antigens and
boosting anti-tumor T cell-mediated immune responses. However, the actual ability of APL-primed T cells to cross-recognize
natural epitopes expressed by tumor cells remains a crucial concern. In the present study, we show that CAP1-6D, a superagonist
analogue of a carcinoembriyonic antigen (CEA)-derived HLA-A*0201-restricted epitope widely used in clinical setting, reproducibly
promotes the generation of low-affinity CD8+ T cells lacking the ability to recognized CEA-expressing colorectal carcinoma (CRC) cells. Short-term T cell cultures, obtained
by priming peripheral blood mononuclear cells from HLA-A*0201+ healthy donors or CRC patients with CAP1-6D, were indeed found to heterogeneously cross-react with saturating concentrations
of the native peptide CAP1, but to fail constantly lysing or recognizing through IFN- γ release CEA+CRC cells. Characterization of anti-CAP1-6D T cell avidity, gained through peptide titration, CD8-dependency assay, and staining
with mutated tetramers (D227K/T228A), revealed that anti-CAP1-6D T cells exerted a differential interaction with the two CEA
epitopes, i.e., displaying high affinity/CD8-independency toward the APL and low affinity/CD8-dependency toward the native
CAP1 peptide. Our data demonstrate that the efficient detection of self-antigen expressed by tumors could be a feature of
high avidity CD8-independent T cells, and underline the need for extensive analysis of tumor cross-recognition prior to any
clinical usage of APL as anti-cancer vaccines. 相似文献
15.
Antigen-specific CD4+ T cells play a critical role in protective immunity to many infectious pathogens. Although the antigen-specific CD4+ T cells can be measured by functional assays such as proliferation or cytokine enzyme-linked immunospot, such assays are limited to a specific function and cannot quantify anergic or suppressed T cells. In contrast, major histocompatiblity complex (MHC) class II tetramers can enumerate epitope-specific CD4+ T cells independent of function. In this paper, we report the construction of bovine leukocyte antigen MHC class II tetramers using a novel mammalian cell system to express soluble class II DRA/DRB3 molecules and defined immunodominant peptide epitopes of Anaplasma marginale major surface proteins (MSPs). Phycoerythrin-labeled tetramers were either loaded with exogenous peptide or constructed with the peptide epitope linked to the N terminus of the DRB3 chain. A DRB3*1101 tetramer loaded with MSP1a peptide F2-5B (ARSVLETLAGHVDALG) and DRB3*1201 tetramers loaded with MSP1a peptide F2-1-1b (GEGYATYLAQAFA) or MSP2 peptide P16-7 (NFAYFGGELGVRFAF) specifically stained antigen-specific CD4+ T cell lines and clones. Tetramers constructed with the T-cell epitope linked to the DRB3 chain were slightly better at labeling CD4+ T cells. In one cell line, the number of tetramer-positive T cells increased to approximately 94% of the CD4+ T cells after culture for 21 weeks with specific antigen. This novel technology should be useful to track the fate of antigen-specific CD4+ T-cell responses in cattle after immunization or infection with persistent pathogens, such as A. marginale, that modulate the host immune response. 相似文献
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18.
Appel H Kuon W Kuhne M Wu P Kuhlmann S Kollnberger S Thiel A Bowness P Sieper J 《Arthritis research & therapy》2004,6(6):R521-R534
Reports of the use of HLA-B27/peptide tetrameric complexes to study peptide-specific CD8+ T cells in HLA-B27+-related diseases are rare. To establish HLA-B27 tetramers we first compared the function of HLA-B27 tetramers with HLA-A2
tetramers by using viral epitopes. HLA-B27 and HLA-A2 tetramers loaded with immunodominant peptides from Epstein–Barr virus
were generated with comparable yields and both molecules detected antigen-specific CD8+ T cells. The application of HLA-B27 tetramers in HLA-B27-related diseases was performed with nine recently described Chlamydia-derived peptides in synovial fluid and peripheral blood, to examine the CD8+ T cell response against Chlamydia trachomatis antigens in nine patients with Chlamydia-triggered reactive arthritis (Ct-ReA). Four of six HLA-B27+ Ct-ReA patients had specific synovial T cell binding to at least one HLA-B27/Chlamydia peptide tetramer. The HLA-B27/Chlamydia peptide 195 tetramer bound to synovial T cells from three of six patients and HLA-B27/Chlamydia peptide 133 tetramer to synovial T cells from two patients. However, the frequency of these cells was low (0.02–0.09%). Moreover,
we demonstrate two methods to generate HLA-B27-restricted T cell lines. First, HLA-B27 tetramers and magnetic beads were used
to sort antigen-specific CD8+ T cells. Second, Chlamydia-infected dendritic cells were used to stimulate CD8+ T cells ex vivo. Highly pure CD8 T cell lines could be generated ex vivo by magnetic sorting by using HLA-B27 tetramers loaded with an EBV peptide. The frequency of Chlamydia-specific, HLA-B27 tetramer-binding CD8+ T cells could be increased by stimulating CD8+ T cells ex vivo with Chlamydia-infected dendritic cells. We conclude that HLA-B27 tetramers are a useful tool for the detection and expansion of HLA-B27-restricted
CD8+ T cells. T cells specific for one or more of three Chlamydia-derived peptides were found at low frequency in synovial fluid from HLA-B27+ patients with Ct-ReA. These cells can be expanded ex vivo, suggesting that they are immunologically functional. 相似文献
19.
Waeckerle-Men Y Uetz-von Allmen E Fopp M von Moos R Böhme C Schmid HP Ackermann D Cerny T Ludewig B Groettrup M Gillessen S 《Cancer immunology, immunotherapy : CII》2006,55(12):1524-1533
Background: Dendritic cell (DC)-based immunotherapy is a promising approach to augment tumor antigen-specific T cell responses in cancer patients. However, tumor escape with down-regulation or complete loss of target antigens may limit the susceptibility of tumor cells to the immune attack. Concomitant generation of T cell responses against several immunodominant antigens may circumvent this potential drawback. In this trial, we determined the immunostimulatory capacity of autologous DC pulsed with multiple T cell epitopes derived from four different prostate-specific antigens in patients with advanced hormone-refractory prostate cancer. Patients and methods: Autologous DC of HLA-A*0201+ patients with hormone-refractory prostate cancer were loaded with antigenic peptides derived from prostate stem cell antigen (PSCA14–22), prostatic acid phosphatase (PAP299–307), prostate-specific membrane antigen (PSMA4–12), and prostate-specific antigen (PSA154–163). DC were intradermally applied six times at biweekly intervals followed—in the case of an enhanced immune response—by monthly booster injections. Immune monitoring during the time of ongoing vaccinations (12–59 weeks) included ex vivo ELISPOT measurements, MHC tetramer analysis and in vitro cytotoxicity assays. Results: Of the initial six patients, three qualified for long-term multi-epitope DC vaccination. This regime was tolerated well by all three patients. The vaccination elicited significant cytotoxic T cell responses against all prostate-specific antigens tested. In addition, memory T cell responses against the control peptides derived from influenza matrix protein and tetanus toxoid were efficiently boosted. Clinically, the long-term DC vaccination was associated with an increase in PSA doubling time. Conclusions: DC-based multi-epitope immunotherapy with repeated boosting in men with hormone-refractory prostate carcinoma is feasible and generates efficient cellular antitumor responses.
Grant
sponsors: Cancer League St. Gallen-Appenzell; Swiss Cancer League; Foundation Propter Homines Vaduz Liechtenstein; Cancer Research Institute USA; Foundation for Clinical Cancer Research of Eastern Switzerland (OSKK) 相似文献
20.
Pedro A. Andrade Filho Daisuke Ito Albert B. DeLeo Robert L. Ferris 《Cancer immunology, immunotherapy : CII》2010,59(10):1561-1568
The TP53 tumor suppressor gene contains a well-studied polymorphism that encodes either proline (P) or arginine (R) at codon
72, and over half of the world’s population is homozygous for R at this codon. The wild-type sequence (wt) p53 peptide, p5365–73, has been identified as a CD8+ T cell-defined tumor antigen for use in broadly applicable cancer vaccines. However, depending
on the TP53 codon 72 polymorphism of the recipient, the induced responses to the peptides incorporating R (p5372R) or P (p5372P) can be “self” or “non-self.” Thus, we sought to determine which wt p5365–73 peptide should be used in wt p53-based cancer vaccines. Despite similar predicted HLA-A2-binding affinities, the p5372P peptide was more efficient than the p5372R peptide in HLA-A2 stabilization assays. In vitro stimulation (IVS) of CD8+ T cells obtained from healthy HLA-A2+ donors with these two peptides led to the generation of CD8+ T cell effectors in one-third of the samples tested, at a frequency
similar to the responsiveness to other wt p53 peptides. Interestingly, regardless of their p53 codon 72 genotype, CD8+ T cells
stimulated with either p5372P or p5372R peptide were cross-reactive against T2 cells pulsed with either peptide, as well as HLA-A2+ head and neck cancer (HNC) cell lines presenting p5372P and/or p5372R peptides for T cell recognition. Therefore, the cross-reactivity of CD8+ T cells for the polymorphic wt p5365–73 peptides, irrespective of their p53 codon 72 polymorphism, suggests that employing either peptide in wt p53-based vaccines
can result in efficient targeting of this epitope. 相似文献