Nitrosylation of Platelet MHC Class I Molecules Directs Their Movement into the Immunosuppressive MHC Class I Processing Pathway within Antigen Presenting Cells.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 837-837
Author(s):  
John W. Semple ◽  
Edwin R. Speck ◽  
John Freedman
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Mhc Class I ◽  
Cd8 T Cells ◽  
Brefeldin A ◽  
Antigen Presenting Cells ◽  
Class I ◽  
Antigen Presenting ◽  
Platelet Transfusions

Abstract Previous studies have demonstrated that recipient mice require the production of nitric oxide (NO) within their antigen presenting cells (APC) in order to generate IgG anti-donor immunity against allogeneic platelet transfusions. NO has a complex biochemistry and several of its conjurors could be involved in this response; the most obvious is peroxynitrite (ONOO-) generated by the spontaneous combination of NO and superoxide (O2•−). ONOO- is a potent oxidant that can spontaneously nitrosylate lysine and tyrosine residues in proteins within the phagolysosome. To address the role of ONOO- in platelet immunity, we transfused GP91 PHOX knockout mice that lack the ability to produce O2•− and thus ONOO-. Results show that when wild type C57BL/6 mice were transfused with allogeneic BALB/c platelets, they developed a weak IgG anti-donor antibody response by the fifth transfusion. In contrast, PHOX KO mice generated IgG anti-donor antibodies by the 2nd transfusion and their IgG anti-donor antibody titres were significantly higher than the WT recipients. This suggested that ONOO- and protein nitrosylation may be linked with an immunosuppressive event within the recipient. This was confirmed by demonstrating that in vitro nitrosylation of platelet antigens with the ONOO- donor SIN-1 inhibited the ability of the platelets to mount an IgG immune response when transfused into allogeneic recipients. Nitrosylated platelet antigen trafficking within recipient APC was assessed by using adherent macrophages and various inhibitors of processing. When adherent APC were pulsed with nitrosylated platelet antigens in the presence of either Brefeldin A or proteosome inhibitors, IgG anti-platelet immunity against the platelets was restored. Furthermore, the IgG immunity could also be rescued against the nitrsosylated platelets if the recipients were first depleted of CD8+ T cells by injection of a monoclonal antibody. These results suggest that if platelet antigens are nitrosylated within antigen presenting cells, they are preferentially shunted to the MHC class I processing pathway and presented to CD8+ T cells that suppress the IgG immune response. Thus, it appears that reactive oxygen species act as intracellular regulators that determine whether a productive IgG immune response against platelet transfusions will occur.

Sialoadhesin-Positive Host Macrophages Play an Essential Role in Graft-Versus-Leukemia Reactivity in Mice

Blood ◽  
1999 ◽  
Vol 93 (12) ◽  
pp. 4375-4386 ◽  
Author(s):  
Susanne Müerköster ◽  
Marian Rocha ◽  
Paul R. Crocker ◽  
Volker Schirrmacher ◽  
Victor Umansky
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mhc Class I ◽  
Mhc Class Ii ◽  
Cd8 T Cells ◽  
Class I ◽  
Peptide Epitope ◽  
Peptide Epitopes ◽  
Graft Versus Leukemia

We recently established an effective immune T-cell–mediated graft-versus-leukemia (GVL) murine model system in which complete tumor remissions were achievable even in advanced metastasized cancer. We now describe that this T-cell–mediated therapy is dependent on host macrophages expressing the lymphocyte adhesion molecule sialoadhesin (Sn). Depletion of Kupffer cells in tumor-bearing mice during adoptive immunotherapy (ADI) or the treatment of these animals with anti-Sn monoclonal antibodies led to complete or partial inhibition of the immune T-cell–mediated therapeutic effect. Furthermore, Sn+ host macrophages in livers formed clusters during ADI with donor CD8 T cells. To test for a possible antigen presentation function of these macrophages, we used as an in vitro model the antigen β-galactosidase for which a dominant major histocompatibility complex (MHC) class I Ld-restricted peptide epitope is known to be recognized by specific CD8 cytotoxic T lymphocytes (CTL). We demonstrate that purified Sn+ macrophages can process exogenous β-galactosidase and stimulate MHC class I peptide-restricted CTL responses. Thus, Sn+ macrophages, which are significantly increased in the liver after ADI, may process tumor-derived proteins via the MHC class I pathway as well as via the MHC class II pathway, as shown previously, and present respective peptide epitopes to CD8 as well as to CD4 immune T cells, respectively. The synergistic interactions observed before between immune CD4 and CD8 T cells during ADI could thus occur in the observed clusters with Sn+ host macrophages.

Sialoadhesin-Positive Host Macrophages Play an Essential Role in Graft-Versus-Leukemia Reactivity in Mice

Blood ◽  
1999 ◽  
Vol 93 (12) ◽  
pp. 4375-4386 ◽  
Author(s):  
Susanne Müerköster ◽  
Marian Rocha ◽  
Paul R. Crocker ◽  
Volker Schirrmacher ◽  
Victor Umansky
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mhc Class I ◽  
Mhc Class Ii ◽  
Cd8 T Cells ◽  
Class I ◽  
Peptide Epitope ◽  
Peptide Epitopes ◽  
Graft Versus Leukemia

Abstract We recently established an effective immune T-cell–mediated graft-versus-leukemia (GVL) murine model system in which complete tumor remissions were achievable even in advanced metastasized cancer. We now describe that this T-cell–mediated therapy is dependent on host macrophages expressing the lymphocyte adhesion molecule sialoadhesin (Sn). Depletion of Kupffer cells in tumor-bearing mice during adoptive immunotherapy (ADI) or the treatment of these animals with anti-Sn monoclonal antibodies led to complete or partial inhibition of the immune T-cell–mediated therapeutic effect. Furthermore, Sn+ host macrophages in livers formed clusters during ADI with donor CD8 T cells. To test for a possible antigen presentation function of these macrophages, we used as an in vitro model the antigen β-galactosidase for which a dominant major histocompatibility complex (MHC) class I Ld-restricted peptide epitope is known to be recognized by specific CD8 cytotoxic T lymphocytes (CTL). We demonstrate that purified Sn+ macrophages can process exogenous β-galactosidase and stimulate MHC class I peptide-restricted CTL responses. Thus, Sn+ macrophages, which are significantly increased in the liver after ADI, may process tumor-derived proteins via the MHC class I pathway as well as via the MHC class II pathway, as shown previously, and present respective peptide epitopes to CD8 as well as to CD4 immune T cells, respectively. The synergistic interactions observed before between immune CD4 and CD8 T cells during ADI could thus occur in the observed clusters with Sn+ host macrophages.

An analysis of the adaptive immune response towards an embryonic stem cell grafts

2007 ◽  
Vol 30 (4) ◽  
pp. 98
Author(s):  
Douglas Wu ◽  
Kathryn Wood
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Mhc Class I ◽  
Cd8 T Cells ◽  
Es Cells ◽  
Embryonic Stem ◽  
Adaptive Immune Response ◽  
Class I ◽  
Es Cell ◽  
Mhc Class I Molecule

Background: Although clinical transplantation has had enormous impact on the treatment of premature organ failure, shortage of donor organs continues to be a crucial limiting factor. Embryonic stem cells represent an attractive potential source of replacement tissue because of their inherent pluripotentiality and ability to self-renew. However, before any ES cell-based cellular replacement strategies can be considered, many issues must be addressed. Among these is an evaluation of the potential immune response elicited by any ES cell graft. Because ES cells express very low levels of MHC class I and no MHC class II, their immunogenicity has been questioned. Here we utilize a BM3 TCR transgenic model to analyze the adaptive immune response against an ES cell graft in vivo. Methods: BM3 CD8 TCR-tg T cells (H2K background) specific for the MHC class I molecule H2Kb were labelled with CFSE and adoptively transferred into CBA rag recipients. The following day, ES cells derived from a CBA, B6, or CBK background were implanted beneath the kidney capsule of adoptively transferred mice. Response of the CD8 T cells was measured via CSFE division profiling and graft infiltration. Results: CFSE division profile of naïve BM3 CD8 T cells was unaltered by the presence of either a syngeneic or an allogeneic ES cell graft. These naïve cells were also unable to recognize and infiltrate either a syngeneic or allogeneic ES cell graft on days 5 and 10 post-implantation, despite strong expression of the MHC class I molecule H2Kb by engrafted allogeneic ES cells. On the other hand, H2Kb+ islets begun to be infiltrated by day 5, and were obliterated by a vigorous allogeneic response by day 10. When H2Kb+ islets were implanted into the same kidney as allogeneic ES cells (opposite poles), islet grafts were rapidly infiltrated by CD4 and CD8 T cells and destroyed, but ES cell grafts exhibited markedly reduced cellular infiltrate. In contrast to naïve BM3 CD8 T cells, however, activated cells recognized and mounted an aggressive cytotoxic response against an allogeneic ES cell graft which could be detected by day 6 and resulted in complete graft destruction by day 10. Conclusions: Under certain circumstances, an ES cell graft may have reduced immunogenicity as compared with other conventional tissue or solid organ allografts. This may be due to their lack of passenger APC, which may in turn cripple their ability to elicit a robust allogeneic response via the direct pathway of allorecognition. However, because of their strong upregulation of allogeneic MHC class I molecules after transplantation, they are still likely to elicit a significant rejection response when transplanted into recipients replete with both CD4 and CD8 T cells.

Immunological relevance of the tumor associated antigen (TAA) COA-1 in colorectal cancer (CRC)

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 13590-13590
Author(s):  
D. C. Corsi ◽  
C. Maccalli ◽  
M. Ciaparrone ◽  
A. F. Scinto ◽  
G. Cucchiara ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Cd8 T Cells ◽  
Cd4 T Cells ◽  
Specific Antigen ◽  
Class Ii ◽  
Hla Typing ◽  
Class I ◽  
Mhc Molecules

13590 Background: Immunotherapy (IT) in CRC has often produced discouraging results. COA-1 is a new TAA recognized by CD4+ T cells from peripheral blood (PB) of a CRC pt; its immunogenic epitope is presented on the surface of tumor cells in association with DRβ1*1301 or *0402 HLA class II molecules. Our aim is verifying whether an immune response directed against COA-1 mediated by CD4+ T cells can be isolated from PB of CRC pts. To achieve a more efficient anti-tumor response a recognition of a specific antigen by both the CD4+ and CD8+ lymphocytes should be performed; so different epitopes deriving from the processing of the same antigen should be presented to the immune system in association with both class I and class II MHC molecules. We identified a list of COA-1 derived peptides with the calculated score for the binding to HLA-A2, the more common HLA class I molecule within the Caucasian population. A failure in generating COA-1 specific T cells was observed in stage I-II CRC pts. Methods: From Jan 04 to day PB samples from 36 CRC pts (14 stage III/ 22 stage IV) have been collected and the HLA typing has been performed. Pts. expressing HLA DRbβ*0402, HLA DRβ1*1301 or HLA-A2 have been selected to collect other blood drawns and verifying whether an immune response directed against COA-1 could be isolated from their PB. Results: 4 pts were positive for the expression of DRβ1*1301 and 2 for the expression of DRβ1*0402. PB lymphocytes have been in vitro stimulated with the COA-1 derived epitopes and tumor reactivity has been verified. An immune response directed to COA-1 was detected in the PB of these 6 pts; anti-COA-1 CD4+ T cells were in vitro isolated and their cytotoxicity measured by granzyme B release. 9 pts were positive for the expression of HLA-A2 and we are stimulating the lymphocytes isolated from these pts with 6 selected COA-1 derived peptides binding the HLA-A2. We observed specific CD8+ T cells for 2 peptides in 1 pt. Conclusions: Our data identify COA-1 like an immunogenic antigen that can evoke an anti-tumor immune response CD4+ mediated in CRC; the response correlates with disease progression. Experiments are ongoing to evaluate an immune response mediated by both CD4+ and CD8+ T cells. These results will determine whether COA-1 could be used for future protocols of IT in CRC. No significant financial relationships to disclose.

scholarly journals The natural immune response to inhaled soluble protein antigens involves major histocompatibility complex (MHC) class I-restricted CD8+ T cell-mediated but MHC class II-restricted CD4+ T cell-dependent immune deviation resulting in selective suppression of immunoglobulin E production.

1993 ◽  
Vol 178 (3) ◽  
pp. 889-899 ◽  
Author(s):  
C McMenamin ◽  
P G Holt
Keyword(s):  
T Cells ◽  
T Cell ◽  
Mhc Class I ◽  
Mhc Class Ii ◽  
Cd8 T Cells ◽  
Immunoglobulin E ◽  
Cd8 T Cell ◽  
T Cell Response ◽  
Class I

The immunological basis for atopy is currently ascribed to an inherent bias in the CD4+ T cell response to nonreplicating antigens presented at mucosal surfaces, resulting in dominance of the T helper 2 (Th2) interleukin 4 (IL-4)-producing phenotype, which favors IgE production. In contrast, the "normal" response to such antigens involves a predominance of interferon gamma (IFN-gamma)-producing Th1 clones. This difference has been suggested to be the result of active selection in atopics for Th2 (and hence against Th1) clones at the time of initial antigen presentation. In the study below, we demonstrate that the natural immune response to inhaled protein antigens, particularly in animals expressing the low immunoglobulin E (IgE) responder phenotype, includes a major histocompatibility complex (MHC) class I-restricted CD8+ T cell component, the appearance of which is associated with active suppression of IgE antibody production. Thus, continued exposure of rats to aerosolized ovalbumin (OVA) antigen elicits a transient IgE response, that is terminated by the onset of a state of apparent "tolerance" to further challenge, and this tolerant state is transferable to naive animals with CD8+ T cells. Kinetic studies on in vitro T cell reactivity in these aerosol-exposed rats demonstrated biphasic CD4+ Th2 responses which terminated, together with IgE antibody production, and coincident with the appearance of MHC class I-restricted OVA-specific IFN-gamma-producing CD8+ T cells. However, the latter were not autonomous in vitro and required a source of exogenous IL-2 for initial activation, which in CD(8+)-enriched splenocyte cultures could be provided by small numbers of contaminating OVA-specific CD4+ T cells. This represents the first formal evidence for the induction of an MHC class I-restricted T cell response to natural mucosal exposure to an inert protein antigen, and is consistent with a growing literature demonstrating sensitization of MHC class I-restricted CD8+ T cells by deliberate immunization with soluble proteins. We suggest that crossregulation of MHC class II-restricted CD4+ T cells via cytokine signals generated in parallel CD8+ T cell responses represents a covert and potentially important selection pressure that can shape the nature of host responses to nonreplicating antigens presented at mucosal surfaces.

Reactivity and Specificity of CD8+ T Cells in Mice with Defects in the MHC Class I Antigen-Presenting Pathway

1996 ◽  
Vol 151 (1) ◽  
pp. 123-148 ◽  
Author(s):  
Hans-Gustaf Ljunggren ◽  
Richard Glas ◽  
Johan K. Sandberg ◽  
Klas Karre
Keyword(s):  
T Cells ◽  
Mhc Class I ◽  
Cd8 T Cells ◽  
Class I ◽  
Mhc Class I Antigen ◽  
Antigen Presenting

Vagaries of the ELISpot assay: Specific detection of antigen responsive cells requires purified CD8+ T cells and MHC class I expressing antigen presenting cell lines

2015 ◽  
Vol 157 (2) ◽  
pp. 216-225 ◽  
Author(s):  
Yannick F. Fuchs ◽  
Gregor W. Jainta ◽  
Denise Kühn ◽  
Carmen Wilhelm ◽  
Marc Weigelt ◽  
...  
Keyword(s):  
T Cells ◽  
Mhc Class I ◽  
Cell Lines ◽  
Cd8 T Cells ◽  
Elispot Assay ◽  
Class I ◽  
Specific Detection ◽  
Antigen Presenting Cell ◽  
Antigen Presenting

scholarly journals Stimulation of mature unprimed CD8+ T cells by semiprofessional antigen-presenting cells in vivo.

1992 ◽  
Vol 176 (5) ◽  
pp. 1291-1302 ◽  
Author(s):  
H Kosaka ◽  
C D Surh ◽  
J Sprent
Keyword(s):  
T Cells ◽  
Parental Strain ◽  
Antigen Presenting Cells ◽  
Class I ◽  
Small Subset ◽  
Effector Cells ◽  
Cd8 Cells ◽  
Antigen Presenting

To test whether unprimed CD8+ cells can recognize class I alloantigens presented selectively on non-bone marrow (BM)-derived cells, unprimed parental strain CD8+ cells were transferred to long-term parent-->F1 BM chimeras prepared with supralethal irradiation. Host class I expression in the chimeras was undetectable on BM-derived cells and, in spleen, was limited to low-level staining of vascular endothelium and moderate staining of follicular dendritic cells (a population of nonhemopoietic cells in germinal centers). Despite this restricted expression of antigen, acute blood-to-lymph recirculation of parental strain T cells through the chimeras led to selective trapping of 95% of CD8+ cells reactive to normal F1 spleen antigen presenting cells (APC) in vitro. Subsequently, a small proportion of the trapped cells entered cell division and gave rise to effector cells expressing strong host-specific CTL activity. The activation of host-specific CD8+ cells was also prominent in double-irradiated chimeras, and cell separation studies showed that the effector cells were generated from resting precursor cells rather than from memory-phenotype cells. It is suggested that the non-BM-derived cells in the chimeras acted as semiprofessional APC. These cells were nonimmunogenic for most host-reactive CD8+ cells but were capable of stimulating a small subset of high-affinity T cells. The possible relevance of the data to the prolonged immunogenicity of vascularized allografts in humans is discussed.

T Cell Responses to AAV Vector Capsid Limit the Duration of Transgene Expression in Humans after Liver-Directed Gene Therapy.

Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 3055-3055
Author(s):  
Federico Mingozzi ◽  
Marcela V. Maus ◽  
Denise E. Sabatino ◽  
Daniel Hui ◽  
Catherine S. Manno ◽  
...  
Keyword(s):  
Clinical Trial ◽  
Gene Therapy ◽  
T Cells ◽  
T Cell ◽  
Mhc Class I ◽  
Cd8 T Cells ◽  
Transgene Expression ◽  
Class I ◽  
Homologous Peptide

Abstract In a Phase I/II study of gene transfer for hemophilia B, an adeno-associated viral vector serotype 2 (AAV2) was introduced into the liver of human subjects and therapeutic levels of transgene expression (up to 11% of normal) were reached in one subject. However, the duration of gene expression was limited; four weeks after infusion, levels of circulating factor IX (F.IX) began to decline, and returned to baseline by week 10. This phenomenon was accompanied by a mild, self-limited, increase in liver enzymes (transaminitis). After a similar phenomenon was observed in another subject, the clinical trial was halted. One hypothesis for the loss of transgene expression is that immune mediated destruction of transduced hepatocytes caused the delayed rise in transaminases and loss of F.IX expression. IFNγ ELISpot analysis of peripheral blood mononuclear cells (PBMCs) from subjects in the clinical study and from normal donors, and bioinformatics tools for the prediction of MHC class I binders, were used to define two possible MHC Class I-restricted T cell epitopes for two HLA types common in the general population (B*0702 and B*0801). We then designed MHC class I epitope-specific pentamers for the detection and study of CD8+ T cells reacting to the predicted AAV2 capsid epitopes. Indeed, in the two subjects who developed transaminitis after vector infusion, AAV-specific CD8+ T cells were detected by pentamer staining of PBMCs up to two years later. In contrast, normal donors rarely had detectable AAV-specific CD8+ T cells in peripheral blood; even after several rounds of in vitro stimulation with vector capsid antigens, we often did not find AAV-specific CD8+ T cells by pentamer staining. We also performed functional assays, including intracellular cytokine staining (ICCS) and cytotoxic T lymphocyte (CTL) assays, on expanded AAV-specific T cells from one of the subjects in the clinical trial. An Epstein-Barr-virus-transformed lymphoblastoid cell line (LCL) derived from an HLA-matched donor was incubated with an AAV2 epitope, with the homologous peptide from the AAV-8 capsid sequence, or with a known HIV gag that is also HLA B*0702 restricted. Similarly to what observed in mice (Sabatino et al., unpublished), we found that IFNγ was specifically produced when the expanded T cells were stimulated with AAV antigens of both serotype 2 and serotype 8, but not with the HIV gag epitope, in the context of HLA B*0702. Peptide-loaded LCLs were used as targets in a CTL assay and incubated with in vitro expanded T cells (effectors). Specific lysis was observed at an effector-target ratio of 100:1 for the AAV2 epitope and for the homologous peptide from the AAV8 capsid. Together, these data provide direct evidence that humans can mount a cytotoxic immune response to AAV capsid proteins. This T cell response may account for the limited duration of transgene expression that we have observed in our clinical study. Moreover, the use of alternate serotypes may not easily avoid this immune response, as T cells from subjects infused with AAV2 showed functional responses to AAV8-derived peptides by both ICCS and CTL assays. We conclude that the use of immunomodulatory therapy may be a better approach to ensure durable transgene expression in the setting of liver-directed gene therapy.

Sign in / Sign up

Export Citation Format

Share Document