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Anyalebechi JC, Sun Y, Davis C, Wagener ME, Liang Z, Burd EM, Coopersmith CM, Ford ML. CD8 + T cells are necessary for improved sepsis survival induced by CD28 agonism in immunologically experienced mice. Front Immunol 2024; 15:1346097. [PMID: 38633258 PMCID: PMC11021695 DOI: 10.3389/fimmu.2024.1346097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Accepted: 03/19/2024] [Indexed: 04/19/2024] Open
Abstract
Introduction A hallmark of T cell dysregulation during sepsis is the downregulation of costimulatory molecules. CD28 is one of T cell costimulatory molecules significantly altered on memory T cells during sepsis. We recently showed that treatment with a αCD28 agonist in septic immunologically experienced mice led to improved survival. Therefore, here we aimed to identify the cell subset(s) necessary for the survival benefit observed in the context of CD28 agonism, and to further investigate the mechanism by which CD28 agonism improves sepsis survival in immunologically experienced mice. Methods: Mice received specific pathogen inoculation to generate memory T cell populations similar in frequency to that of adult humans. Once these infections were cleared and the T cell response had transitioned to the memory phase, animals were rendered septic via cecal ligation and puncture in the presence or absence of an agonistic anti-CD28 mAb. Results Results demonstrated that CD8+ T cells, and not bulk CD4+ T cells or CD25+ regulatory T cells, were necessary for the survival benefit observed in CD28 agonist-treated septic immunologically experienced mice. Upon examination of these CD8+ T cells, we found that CD28 agonism in septic immunologically experienced mice was associated with an increase in Foxp3+ CD8+ T cells as compared to vehicle-treated controls. When CD8+ T cells were depleted in septic immunologically experienced mice in the setting of CD28 agonism, a significant increase in levels of inflammatory cytokines in the blood was observed. Discussion Taken together, these results indicate that CD28 agonism in immunologically experienced mice effectively suppresses inflammation via a CD8+-dependent mechanism to decrease mortality during sepsis.
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Affiliation(s)
- Jerome C. Anyalebechi
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Yini Sun
- Department of Critical Care Medicine, The First Affiliated Hospital of China Medical University, China Medical University, Shenyang, China
| | - Carolyn Davis
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Maylene E. Wagener
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, United States
| | - Zhe Liang
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Eileen M. Burd
- Department of Pathology and Laboratory Medicine, Emory University, Atlanta, GA, United States
| | - Craig M. Coopersmith
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Emory Critical Care Center, Emory University School of Medicine, Atlanta, GA, United States
| | - Mandy L. Ford
- Department of Surgery, Emory University School of Medicine, Atlanta, GA, United States
- Emory Transplant Center, Emory University School of Medicine, Atlanta, GA, United States
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Habib JG, Liu D, Crepeau RM, Wagener ME, Ford ML. Selective CD28 blockade impacts T cell differentiation during homeostatic reconstitution following lymphodepletion. Front Immunol 2023; 13:1081163. [PMID: 36761170 PMCID: PMC9904166 DOI: 10.3389/fimmu.2022.1081163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 12/28/2022] [Indexed: 01/26/2023] Open
Abstract
Introduction Costimulation blockade targeting the CD28 pathway provides improved long-term renal allograft survival compared to calcineurin inhibitors but may be limited as CTLA-4-Ig (abatacept, belatacept) blocks both CD28 costimulation and CTLA-4 coinhibition. Directly targeting CD28 while leaving CTLA-4 intact may provide a mechanistic advantage. Fc-silent non-crosslinking CD28 antagonizing domain antibodies (dAb) are currently in clinical trials for renal transplantation. Given the current standard of care in renal transplantation at most US centers, it is likely that lymphodepletion via thymoglobulin induction therapy could be used in patients treated with CD28 antagonists. Thus, we investigated the impact of T cell depletion (TCD) on T cell phenotype following homeostatic reconstitution in a murine model of skin transplantation treated with anti-CD28dAb. Methods Skin from BALB/cJ donors was grafted onto C56BL/6 recipients which were treated with or without 0.2mg anti-CD4 and 10μg anti-CD8 one day prior to transplant and with or without 100μg anti-CD28dAb on days 0, 2, 4, 6, and weekly thereafter. Mice were euthanized six weeks post-transplant and lymphoid cells were analyzed by flow cytometry. Results Anti-CD28dAb reversed lymphopenia-induced differentiation of memory CD4+ T cells in the spleen and lymph node compared to TCD alone. Mice treated with TCD+anti-CD28dAb exhibited significantly improved skin graft survival compared to anti-CD28dAb alone, which was also improved compared to no treatment. In addition, the expression of CD69 was reduced on CD4+ and CD8+ T cells in the spleen and lymph node from mice that received TCD+anti-CD28dAb compared to TCD alone. While a reduced frequency of CD4+FoxP3+ T cells was observed in anti-CD28dAb treated mice relative to untreated controls, this was balanced by an increased frequency of CD8+Foxp3+ T cells that was observed in the blood and kidney of mice given TCD+anti-CD28dAb compared to TCD alone. Discussion These data demonstrate that CD28 signaling impacts the differentiation of both CD4+ and CD8+ T cells during homeostatic reconstitution following lymphodepletion, resulting in a shift towards fewer activated memory T cells and more CD8+FoxP3+ T cells, a profile that may underpin the observed prolongation in allograft survival.
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La Muraglia GM, Zeng S, Crichton ES, Wagener ME, Ford ML, Badell IR. Superior inhibition of alloantibody responses with selective CD28 blockade is CTLA-4 dependent and T follicular helper cell specific. Am J Transplant 2021; 21:73-86. [PMID: 32406182 PMCID: PMC7665991 DOI: 10.1111/ajt.16004] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Revised: 04/15/2020] [Accepted: 05/07/2020] [Indexed: 01/25/2023]
Abstract
Anti-donor antibodies cause immunologic injury in transplantation. CD28 blockade with CTLA-4-Ig has the ability to reduce the incidence of these donor-specific antibodies (DSA), but its mechanism is suboptimal for the inhibition of alloimmunity in that CTLA-4-Ig blocks both CD28 costimulation and CTLA-4 coinhibition. Thus selective CD28 blockade that spares CTLA-4 has potential to result in improved inhibition of humoral alloimmunity. To test this possibility, we utilized a full allogeneic mismatch murine transplant model and T follicular helper (Tfh):B cell co-culture system. We observed that selective blockade with an anti-CD28 domain antibody (dAb) compared to CTLA-4-Ig led to superior inhibition of Tfh cell, germinal center, and DSA responses in vivo and better control of B cell responses in vitro. CTLA-4 blockade enhanced the humoral alloresponse and, in combination with anti-CD28 dAb, abrogated the effects of selective blockade. This CTLA-4-dependent inhibition was Tfh cell specific in that CTLA-4 expression by Tfh cells was necessary and sufficient for the improved humoral inhibition observed with selective CD28 blockade. As CD28 blockade attracts interest for control of alloantibodies in the clinic, these data support selective CD28 blockade as a superior strategy to address DSA via the sparing of CTLA-4 and more potent targeting of Tfh cells.
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Affiliation(s)
| | - Susan Zeng
- Emory Transplant Center, Atlanta, GA, USA
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Yoseph BP, Breed E, Overgaard CE, Ward CJ, Liang Z, Wagener ME, Lexcen DR, Lusczek ER, Beilman GJ, Burd EM, Farris AB, Guidot DM, Koval M, Ford ML, Coopersmith CM. Correction: Chronic Alcohol Ingestion Increases Mortality and Organ Injury in a Murine Model of Septic Peritonitis. PLoS One 2020; 15:e0239568. [PMID: 32941549 PMCID: PMC7498101 DOI: 10.1371/journal.pone.0239568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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La Muraglia GM, Wagener ME, Ford ML, Badell IR. Circulating T follicular helper cells are a biomarker of humoral alloreactivity and predict donor-specific antibody formation after transplantation. Am J Transplant 2020; 20:75-87. [PMID: 31250973 PMCID: PMC7193899 DOI: 10.1111/ajt.15517] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2019] [Revised: 06/15/2019] [Accepted: 06/16/2019] [Indexed: 01/25/2023]
Abstract
Donor-specific antibodies (DSAs) contribute to renal allograft loss. However, biomarkers to guide clinical management of DSA posttransplant or detect humoral alloimmune responses before alloantibodies develop are not available. Circulating T follicular helper (cTfh) cells are CD4+ CXCR5+ Tfh-like cells in the blood that have been associated with alloantibodies in transplant recipients, but whether they precede antibody formation for their evaluation as a predictive biomarker in transplant is unknown. To evaluate the ability of cTfh cells to predict DSA, we used murine transplant models to determine the temporal relationship between cTfh cells, germinal center formation, and DSA development. We observed that donor-reactive CD4+ CXCR5+ cTfh cells expand after allotransplant. These cTfh cells were equivalent to graft-draining lymph node-derived Tfh cells in their ability to provide B cell help for antibody production. cTfh cell expansion and differentiation into ICOS+ PD-1+ cells temporally correlated with germinal center alloreactivity and preceded the generation of DSAs in instances of modified and unmodified alloantibody formation. Importantly, delayed costimulation blockade initiated after the detection of ICOS+ PD-1+ cTfh cells prevented DSAs. These findings suggest that cTfh cells could serve as a biomarker for humoral alloreactivity before the detection of alloantibodies and inform therapeutic approaches to prevent DSAs.
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Affiliation(s)
| | | | | | - I. Raul Badell
- Emory Transplant Center, Atlanta, GA, USA,Corresponding Author: I. Raul Badell,
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Laurie SJ, Liu D, Wagener ME, Stark PC, Terhorst C, Ford ML. 2B4 Mediates Inhibition of CD8 + T Cell Responses via Attenuation of Glycolysis and Cell Division. J Immunol 2018; 201:1536-1548. [PMID: 30012849 DOI: 10.4049/jimmunol.1701240] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 06/11/2018] [Indexed: 12/17/2022]
Abstract
We recently showed that 2B4 expression on memory T cells in human renal transplant recipients was associated with reduced rates of rejection. To investigate whether 2B4 functionally underlies graft acceptance during transplantation, we established an experimental model in which 2B4 was retrogenically expressed on donor-reactive murine CD8+ T cells (2B4rg), which were then transferred into naive recipients prior to skin transplantation. We found that constitutive 2B4 expression resulted in significantly reduced accumulation of donor-reactive CD8+ T cells following transplantation and significantly prolonged graft survival following transplantation. This marked reduction in alloreactivity was due to reduced proliferation of CD8+ Thy1.1+ 2B4rg cells as compared with control cells, underpinned by extracellular flux analyses demonstrating that 2B4-deficient (2B4KO) CD8+ cells activated in vitro exhibited increased glycolytic capacity and upregulation of gene expression profiles consistent with enhanced glycolytic machinery as compared with wild type controls. Furthermore, 2B4KO CD8+ T cells primed in vivo exhibited significantly enhanced ex vivo uptake of a fluorescent glucose analogue. Finally, the proliferative advantage associated with 2B4 deficiency was only observed in the setting of glucose sufficiency; in glucose-poor conditions, 2B4KO CD8+ T cells lost their proliferative advantage. Together, these data indicate that 2B4 signals function to alter T cell glucose metabolism, thereby limiting the proliferation and accumulation of CD8+ T cells. Targeting 2B4 may therefore represent a novel therapeutic strategy to attenuate unwanted CD8+ T cell responses.
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Affiliation(s)
| | - Danya Liu
- Emory Transplant Center, Atlanta, GA 30322; and
| | | | | | - Cox Terhorst
- Beth Israel Deaconess Medical Center, Boston, MA 02215
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Bozeman AM, Laurie SJ, Haridas D, Wagener ME, Ford ML. Transplantation preferentially induces a KLRG-1 lo CD127 hi differentiation program in antigen-specific CD8 + T cells. Transpl Immunol 2018; 50:34-42. [PMID: 29885905 DOI: 10.1016/j.trim.2018.06.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 06/05/2018] [Accepted: 06/06/2018] [Indexed: 11/27/2022]
Abstract
Models of infection have shaped our understanding of programmed memory T cell differentiation, yet whether these models apply to memory programming in the context of transplantation has yet to be defined. Previous work has identified differences in the response of antigen-specific CD8+ T cells to cognate antigen based on the environment in which the antigen is presented. Thus, we hypothesized that programming of antigen specific CD8+ T cells responding to graft and pathogen may be dissimilar. Here we find that antigen-specific CD8+ T cells primed by a skin graft contract faster than those primed by gammaherpesvirus (gHV), yet are able to expand more rapidly upon rechallenge. Moreover, graft-primed antigen-specific CD8+ T cells exhibited higher frequencies of cells secreting IL-2 and demonstrate lower expression of KLRG-1, which are qualities suggestive of increased recall potential. Additionally, the expression of CD127 at a memory time point suggests graft-elicited CD8+ antigen specific T cells are maintained in a less terminally-differentiated state compared to gHV-elicited CD8+ antigen specific T cells, despite fewer cells being present at that time point. Taken together, our findings suggest that the surface marker expression and functional profiles of T cells depends on the priming conditions and may be used to predict immunologic risk following transplantation after traditional allosensitization or heterologous immune priming.
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Affiliation(s)
- Alana M Bozeman
- Emory Transplant Center, Atlanta 30322, Georgia; Division of Pediatric Nephrology, Department of Pediatrics, Children's Healthcare of Atlanta, Atlanta 30322, Georgia
| | | | | | | | - Mandy L Ford
- Emory Transplant Center, Atlanta 30322, Georgia.
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8
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Badell IR, La Muraglia GM, Liu D, Wagener ME, Ding G, Ford ML. Selective CD28 Blockade Results in Superior Inhibition of Donor-Specific T Follicular Helper Cell and Antibody Responses Relative to CTLA4-Ig. Am J Transplant 2018; 18:89-101. [PMID: 28637095 PMCID: PMC5740006 DOI: 10.1111/ajt.14400] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 06/02/2017] [Accepted: 06/13/2017] [Indexed: 01/25/2023]
Abstract
Donor-specific antibodies (DSAs) are a barrier to improved long-term outcomes after kidney transplantation. Costimulation blockade with CTLA4-Ig has shown promise as a potential therapeutic strategy to control DSAs. T follicular helper (Tfh) cells, a subset of CD4+ T cells required for optimal antibody production, are reliant on the CD28 costimulatory pathway. We have previously shown that selective CD28 blockade leads to superior allograft survival through improved control of CD8+ T cells relative to CTLA4-Ig, but the impact of CD28-specific blockade on CD4+ Tfh cells is unknown. Thus, we identified and characterized donor-reactive Tfh cells in a murine skin transplant model and then used this model to evaluate the impact of selective CD28 blockade with an anti-CD28 domain antibody (dAb) on the donor-specific Tfh cell-mediated immune response. We observed that the anti-CD28 dAb led to superior inhibition of donor-reactive CXCR5+ PD-1high Tfh cells, CD95+ GL7+ germinal center B cells and DSA formation compared with CTLA4-Ig. Interestingly, donor-reactive Tfh cells differentially upregulated CTLA4 expression, suggesting an important role for CTLA4 in mediating the superior inhibition observed with the anti-CD28 dAb. Therefore, selective CD28 blockade as a novel approach to control Tfh cell responses and prevent DSA after kidney transplantation warrants further study.
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Affiliation(s)
- IR Badell
- Emory Transplant Center, Atlanta, GA, USA,Corresponding Author: I. Raul Badell, MD,
| | | | - D Liu
- Emory Transplant Center, Atlanta, GA, USA
| | - ME Wagener
- Emory Transplant Center, Atlanta, GA, USA
| | - G Ding
- Emory Transplant Center, Atlanta, GA, USA
| | - ML Ford
- Emory Transplant Center, Atlanta, GA, USA
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9
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Margoles LM, Mittal R, Klingensmith NJ, Lyons JD, Liang Z, Serbanescu MA, Wagener ME, Coopersmith CM, Ford ML. Chronic Alcohol Ingestion Delays T Cell Activation and Effector Function in Sepsis. PLoS One 2016; 11:e0165886. [PMID: 27861506 PMCID: PMC5115670 DOI: 10.1371/journal.pone.0165886] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Accepted: 10/19/2016] [Indexed: 12/21/2022] Open
Abstract
Sepsis is the leading cause of death in intensive care units in the US, and it is known that chronic alcohol use is associated with higher incidence of sepsis, longer ICU stays, and higher mortality from sepsis. Both sepsis and chronic alcohol use are associated with immune deficits such as decreased lymphocyte numbers, impaired innate immunity, delayed-type hypersensitivity reactions, and susceptibility to infections; however, understanding of specific pathways of interaction or synergy between these two states of immune dysregulation is lacking. This study therefore sought to elucidate mechanisms underlying the immune dysregulation observed during sepsis in the setting of chronic alcohol exposure. Using a murine model of chronic ethanol ingestion followed by sepsis induction via cecal ligation and puncture, we determined that while CD4+ and CD8+ T cells isolated from alcohol fed mice eventually expressed the same cellular activation markers (CD44, CD69, and CD43) and effector molecules (IFN-γ, TNF) as their water fed counterparts, there was an overall delay in the acquisition of these phenotypes. This early lag in T cell activation was associated with significantly reduced IL-2 production at a later timepoint in both the CD4+ and CD8+ T cell compartments in alcohol sepsis, as well as with a reduced accumulation of CD8dim activated effectors. Taken together, these data suggest that delayed T cell activation may result in qualitative differences in the immune response to sepsis in the setting of chronic alcohol ingestion.
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Affiliation(s)
- Lindsay M. Margoles
- Division of Infectious Diseases, Emory University, Atlanta, GA, United States of America
| | - Rohit Mittal
- Department of Surgery, Emory University, Atlanta, GA, United States of America
| | | | - John D. Lyons
- Department of Surgery, Emory University, Atlanta, GA, United States of America
| | - Zhe Liang
- Department of Surgery, Emory University, Atlanta, GA, United States of America
| | - Mara A. Serbanescu
- Department of Surgery, Emory University, Atlanta, GA, United States of America
| | - Maylene E. Wagener
- Department of Surgery, Emory University, Atlanta, GA, United States of America
- Emory Transplant Center, Emory University, Atlanta, GA, United States of America
| | - Craig M. Coopersmith
- Department of Surgery, Emory University, Atlanta, GA, United States of America
- Emory Critical Care Center, Emory University, Atlanta, GA, United States of America
| | - Mandy L. Ford
- Department of Surgery, Emory University, Atlanta, GA, United States of America
- Emory Transplant Center, Emory University, Atlanta, GA, United States of America
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Badell IR, Kitchens WH, Wagener ME, Lukacher AE, Larsen CP, Ford ML. Pathogen Stimulation History Impacts Donor-Specific CD8(+) T Cell Susceptibility to Costimulation/Integrin Blockade-Based Therapy. Am J Transplant 2015; 15:3081-94. [PMID: 26228897 PMCID: PMC5416935 DOI: 10.1111/ajt.13399] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Revised: 05/22/2015] [Accepted: 05/26/2015] [Indexed: 01/25/2023]
Abstract
Recent studies have shown that the quantity of donor-reactive memory T cells is an important factor in determining the relative heterologous immunity barrier posed during transplantation. Here, we hypothesized that the quality of T cell memory also potently influences the response to costimulation blockade-based immunosuppression. Using a murine skin graft model of CD8(+) memory T cell-mediated costimulation blockade resistance, we elicited donor-reactive memory T cells using three distinct types of pathogen infections. Strikingly, we observed differential efficacy of a costimulation and integrin blockade regimen based on the type of pathogen used to elicit the donor-reactive memory T cell response. Intriguingly, the most immunosuppression-sensitive memory T cell populations were composed primarily of central memory cells that possessed greater recall potential, exhibited a less differentiated phenotype, and contained more multi-cytokine producers. These data, therefore, demonstrate that the memory T cell barrier is dependent on the specific type of pathogen infection via which the donor-reactive memory T cells are elicited, and suggest that the immune stimulation history of a given transplant patient may profoundly influence the relative barrier posed by heterologous immunity during transplantation.
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Affiliation(s)
- IR Badell
- Emory Transplant Center, Atlanta, GA, USA
| | | | - ME Wagener
- Emory Transplant Center, Atlanta, GA, USA
| | - AE Lukacher
- Department of Microbiology and Immunology, The Pennsylvania State University College of Medicine, Hershey, PA, USA
| | - CP Larsen
- Emory Transplant Center, Atlanta, GA, USA
| | - ML Ford
- Emory Transplant Center, Atlanta, GA, USA
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Pinelli DF, Wakeman BS, Wagener ME, Speck SH, Ford ML. Rapamycin ameliorates the CTLA4-Ig-mediated defect in CD8(+) T cell immunity during gammaherpesvirus infection. Am J Transplant 2015; 15:2576-87. [PMID: 25989700 PMCID: PMC5389899 DOI: 10.1111/ajt.13326] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 03/20/2015] [Accepted: 03/25/2015] [Indexed: 01/25/2023]
Abstract
Latent viral infections are a major concern among immunosuppressed transplant patients. During clinical trials with belatacept, a CTLA4-Ig fusion protein, patients showed an increased risk of Epstein-Barr virus-associated posttransplant lymphoproliferative disorder, thought to be due to a deficient primary CD8(+) T cell response to the virus. Using a murine model of latent viral infection, we observed that rapamycin treatment alone led to a significant increase in virus-specific CD8(+) T cells, as well as increased functionality of these cells, including the ability to make multiple cytokines, while CTLA4-Ig treatment alone significantly dampened the response and inhibited the generation of polyfunctional antigen-specific CD8(+) T cells. However, the addition of rapamycin to the CTLA4-Ig regimen was able to quantitatively and qualitatively restore the antigen-specific CD8(+) T cell response to the virus. This improvement was physiologically relevant, in that CTLA4-Ig treated animals exhibited a greater viral burden following infection that was reduced to levels observed in untreated immunocompetent animals by the addition of rapamycin. These results reveal that modulation of T cell differentiation though inhibition of mTOR signaling can restore virus-specific immune competence even in the absence of CD28 costimulation, and have implications for improving protective immunity in transplant recipients.
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Affiliation(s)
- DF Pinelli
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | | | - ME Wagener
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | - SH Speck
- Emory Vaccine Center, Atlanta, GA
| | - ML Ford
- Emory Transplant Center and Department of Surgery, Atlanta, GA,Corresponding author: Mandy Ford,
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12
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Krummey SM, Floyd TL, Liu D, Wagener ME, Song M, Ford ML. Candida-elicited murine Th17 cells express high Ctla-4 compared with Th1 cells and are resistant to costimulation blockade. J Immunol 2014; 192:2495-504. [PMID: 24493820 DOI: 10.4049/jimmunol.1301332] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Effector and memory T cells may cross-react with allogeneic Ags to mediate graft rejection. Whereas the costimulation properties of Th1 cells are well studied, relatively little is known about the costimulation requirements of microbe-elicited Th17 cells. The costimulation blocker CTLA-4 Ig has been ineffective in the treatment of several Th17-driven autoimmune diseases and is associated with severe acute rejection following renal transplantation, leading us to investigate whether Th17 cells play a role in CD28/CTLA-4 blockade-resistant alloreactivity. We established an Ag-specific model in which Th1 and Th17 cells were elicited via Mycobacterium tuberculosis and Candida albicans immunization, respectively. C. albicans immunization elicited a higher frequency of Th17 cells and conferred resistance to costimulation blockade following transplantation. Compared with the M. tuberculosis group, C. albicans-elicited Th17 cells contained a higher frequency of IL-17(+)IFN-γ(+) producers and a lower frequency of IL-10(+) and IL-10(+)IL-17(+) cells. Importantly, Th17 cells differentially regulated the CD28/CTLA-4 pathway, expressing similarly high CD28 but significantly greater amounts of CTLA-4 compared with Th1 cells. Ex vivo blockade experiments demonstrated that Th17 cells are more sensitive to CTLA-4 coinhibition and therefore less susceptible to CTLA-4 Ig. These novel insights into the differential regulation of CTLA-4 coinhibition on CD4(+) T cells have implications for the immunomodulation of pathologic T cell responses during transplantation and autoimmunity.
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Affiliation(s)
- Scott M Krummey
- Department of Surgery, Emory Transplant Center, Emory University School of Medicine, Atlanta, GA 30322
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13
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Pinelli DF, Wagener ME, Liu D, Yamniuk A, Tamura J, Grant S, Larsen CP, Suri A, Nadler SG, Ford ML. An anti-CD154 domain antibody prolongs graft survival and induces Foxp3(+) iTreg in the absence and presence of CTLA-4 Ig. Am J Transplant 2013; 13:3021-30. [PMID: 24007441 PMCID: PMC4287239 DOI: 10.1111/ajt.12417] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/14/2013] [Accepted: 07/01/2013] [Indexed: 01/25/2023]
Abstract
The use of monoclonal antibodies targeting the CD154 molecule remains one of the most effective means of promoting graft tolerance in animal models, but thromboembolic complications during early clinical trials have precluded their use in humans. Furthermore, the role of Fc-mediated deletion of CD154-expressing cells in the observed efficacy of these reagents remains controversial. Therefore, determining the requirements for anti-CD154-induced tolerance will instruct the development of safer but equally efficacious treatments. To investigate the mechanisms of action of anti-CD154 therapy, two alternative means of targeting the CD40-CD154 pathway were used: a nonagonistic anti-CD40 antibody and an Fc-silent anti-CD154 domain antibody. We compared these therapies to an Fc-intact anti-CD154 antibody in both a fully allogeneic model and a surrogate minor antigen model in which the fate of alloreactive cells could be tracked. Results indicated that anti-CD40 mAbs as well as Fc-silent anti-CD154 domain antibodies were equivalent to Fc-intact anti-CD154 mAbs in their ability to inhibit alloreactive T cell expansion, attenuate cytokine production of antigen-specific T cells and promote the conversion of Foxp3(+) iTreg. Importantly, iTreg conversion observed with Fc-silent anti-CD154 domain antibodies was preserved in the presence of CTLA4-Ig, suggesting that this therapy is a promising candidate for translation to clinical use.
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Affiliation(s)
- DF Pinelli
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | - ME Wagener
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | - D Liu
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | | | - J Tamura
- Bristol Myers Squibb, Princeton, NJ
| | - S Grant
- Domantis/GlaxoSmithKline, Cambridge, United Kingdom
| | - CP Larsen
- Emory Transplant Center and Department of Surgery, Atlanta, GA
| | - A Suri
- Bristol Myers Squibb, Princeton, NJ
| | | | - ML Ford
- Emory Transplant Center and Department of Surgery, Atlanta, GA
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14
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Ferrer IR, Wagener ME, Song M, Ford ML. CD154 blockade alters innate immune cell recruitment and programs alloreactive CD8+ T cells into KLRG-1(high) short-lived effector T cells. PLoS One 2012; 7:e40559. [PMID: 22792369 PMCID: PMC3390379 DOI: 10.1371/journal.pone.0040559] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2012] [Accepted: 06/08/2012] [Indexed: 11/19/2022] Open
Abstract
CD154/CD40 blockade combined with donor specific transfusion remains one of the most effective therapies in prolonging allograft survival. Despite this, the mechanisms by which these pathways synergize to prevent rejection are not completely understood. Utilizing a BALB/c (H2-K(d)) to B6 (H2-K(b)) fully allogeneic skin transplant model system, we performed a detailed longitudinal analysis of the kinetics and magnitude of CD8(+) T cell expansion and differentiation in the presence of CD154/CD40 pathway blockade. Results demonstrated that treatment with anti-CD154 vs. DST had distinct and opposing effects on activated CD44(high) CD62L(low) CD8(+) T cells in skin graft recipients. Specifically, CD154 blockade delayed alloreactive CD8(+) T cell responses, while DST accelerated them. DST inhibited the differentiation of alloreactive CD8(+) T cells into multi-cytokine producing effectors, while CD40/CD154 blockade led to the diminution of the KLRG-1(low) long-lived memory precursor population compared with either untreated or DST treated animals. Moreover, only CD154 blockade effectively inhibited CXCL1 expression and neutrophil recruitment into the graft. When combined, anti-CD154 and DST acted synergistically to profoundly diminish the absolute number of IFN-γ producing alloreactive CD8(+) T cells, and intra-graft expression of inflammatory chemokines. These findings demonstrate that the previously described ability of anti-CD154 and DST to result in alloreactive T cell deletion involves both delayed kinetics of T cell expansion and differentiation and inhibited development of KLRG-1(low) memory precursor cells.
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Affiliation(s)
- Ivana R. Ferrer
- Emory Transplant Center and Department of Surgery, Emory University, Atlanta, Georgia, United States of America
| | - Maylene E. Wagener
- Emory Transplant Center and Department of Surgery, Emory University, Atlanta, Georgia, United States of America
| | - Mingqing Song
- Emory Transplant Center and Department of Surgery, Emory University, Atlanta, Georgia, United States of America
| | - Mandy L. Ford
- Emory Transplant Center and Department of Surgery, Emory University, Atlanta, Georgia, United States of America
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15
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Ferrer IR, Wagener ME, Robertson JM, Turner AP, Araki K, Ahmed R, Kirk AD, Larsen CP, Ford ML. Cutting edge: Rapamycin augments pathogen-specific but not graft-reactive CD8+ T cell responses. J Immunol 2010; 185:2004-8. [PMID: 20631309 DOI: 10.4049/jimmunol.1001176] [Citation(s) in RCA: 97] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Recent evidence demonstrating that exposure to rapamycin during viral infection increased the quantity and quality of Ag-specific T cells poses an intriguing paradox, because rapamycin is used in transplantation to dampen, rather than enhance, donor-reactive T cell responses. In this report, we compared the effects of rapamycin on the Ag-specific T cell response to a bacterial infection versus a transplant. Using a transgenic system in which the Ag and the responding T cell population were identical in both cases, we observed that treatment with rapamycin augmented the Ag-specific T cell response to a pathogen, whereas it failed to do so when the Ag was presented in the context of a transplant. These results suggest that the environment in which an Ag is presented alters the influence of rapamycin on Ag-specific T cell expansion and highlights a fundamental difference between Ag presented by an infectious agent as compared with an allograft.
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Affiliation(s)
- Ivana R Ferrer
- Emory Transplant Center, Emory University, Atlanta, GA 30322, USA
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16
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Coley SM, Ford ML, Hanna SC, Wagener ME, Kirk AD, Larsen CP. IFN-gamma dictates allograft fate via opposing effects on the graft and on recipient CD8 T cell responses. J Immunol 2009; 182:225-33. [PMID: 19109153 PMCID: PMC2683416 DOI: 10.4049/jimmunol.182.1.225] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CD8 T cells are necessary for costimulation blockade-resistant rejection. However, the mechanism by which CD8 T cells mediate rejection in the absence of major costimulatory signals is poorly understood. IFN-gamma promotes CD8 T cell-mediated immune responses, but IFN-gamma-deficient mice show early graft loss despite costimulation blockade. In contrast, we found that IFN-gamma receptor knockout mice show dramatically prolonged graft survival under costimulation blockade. To investigate this paradox, we addressed the effects of IFN-gamma on T cell alloresponses in vivo independent of the effects of IFN-gamma on graft survival. We identified a donor-specific CD8 T cell breakthrough response temporally correlated with costimulation blockade-resistant rejection. Neither IFN-gamma receptor knockout recipients nor IFN-gamma-deficient recipients showed a CD8 breakthrough response. Graft death on IFN-gamma-deficient recipients despite costimulation blockade could be explained by the lack of IFN-gamma available to act on the graft. Indeed, the presence of IFN-gamma was necessary for graft survival on IFN-gamma receptor knockout recipients, as either IFN-gamma neutralization or the lack of the IFN-gamma receptor on the graft precipitated early graft loss. Thus, IFN-gamma is required both for the recipient to mount a donor-specific CD8 T cell response under costimulation blockade as well as for the graft to survive after allotransplantation.
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Affiliation(s)
- Shana M. Coley
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
| | - Mandy L. Ford
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
| | - Samantha C. Hanna
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
| | - Maylene E. Wagener
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
| | - Allan D. Kirk
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
| | - Christian P. Larsen
- Emory Transplant Center, Department of Surgery, Emory University, 101 Woodruff Circle, WMRB Suite 5203, Atlanta, Georgia, 30322, USA
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17
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Ford ML, Wagener ME, Hanna SS, Pearson TC, Kirk AD, Larsen CP. A critical precursor frequency of donor-reactive CD4+ T cell help is required for CD8+ T cell-mediated CD28/CD154-independent rejection. J Immunol 2008; 180:7203-11. [PMID: 18490719 DOI: 10.4049/jimmunol.180.11.7203] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Ag-specific precursor frequency is increasingly being appreciated as an important factor in determining the kinetics, magnitude, and degree of differentiation of T cell responses, and recently was found to play a critical role in determining the relative requirement of CD8(+) T cells for CD28- and CD154-mediated costimulatory signals during transplantation. We addressed the possibility that variations in CD4(+) T cell precursor frequency following transplantation might affect CD4(+) T cell proliferation, effector function, and provision of help for donor-reactive B cell and CD8(+) T cell responses. Using a transgenic model system wherein increasing frequencies of donor-reactive CD4(+) T cells were transferred into skin graft recipients, we observed that a critical CD4(+) T cell threshold precursor frequency was necessary to provide help following blockade of the CD28 and CD154 costimulatory pathways, as measured by increased B cell and CD8(+) T cell responses and precipitation of graft rejection. In contrast to high-frequency CD8(+) T cell responses, this effect was observed even though the proliferative and cytokine responses of Ag-specific CD4(+) T cells were inhibited. Thus, we conclude that an initial high frequency of donor-reactive CD4(+) T cells uncouples T cell proliferative and effector cytokine production from the provision of T cell help.
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Affiliation(s)
- Mandy L Ford
- Department of Surgery and Emory Transplant Center, Emory University, Atlanta, GA 30322, USA.
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18
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Ford ML, Wagener ME, Gangappa S, Pearson TC, Larsen CP. Antigenic disparity impacts outcome of agonism but not blockade of costimulatory pathways in experimental transplant models. Am J Transplant 2007; 7:1471-81. [PMID: 17511677 DOI: 10.1111/j.1600-6143.2007.01826.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Treatment regimens consisting of CTLA-4 Ig/anti-CD154 or agonistic anti-CD28/rapamycin have both been shown to prevent GVHD in fully allogeneic murine model systems. Using a transgenic approach to track the fate of host-reactive T cells in a minor antigen disparity model of GVHD, we found that while treatment with CTLA-4 Ig/anti-CD154 retained efficacy, the costimulation agonist anti-CD28 combined with rapamycin failed to prevent GVHD. Analysis of the host-reactive CD4(+) and CD8(+) T-cell responses revealed that in contrast to CTLA-4Ig/anti-CD154-treated recipients, host-reactive T cells in recipients treated with agonistic anti-CD28/rapamycin displayed enhanced and accelerated T-cell proliferation and failed to undergo activation-induced cell death. An increase in systemic levels of inflammatory cytokines was observed in the anti-CD28/rapamycin-treated recipients of the minor but not major antigen disparity bone marrow transplants. Our results demonstrate the intricacies of costimulatory receptor signaling pathways, and reveal how agonism of the CD28 pathway can have opposing outcomes depending on the degree of antigenic disparity.
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Affiliation(s)
- M L Ford
- Department of Surgery, Emory Transplant Center, Emory University, Atlanta, GA, USA
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19
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Ford ML, Koehn BH, Wagener ME, Jiang W, Gangappa S, Pearson TC, Larsen CP. Antigen-specific precursor frequency impacts T cell proliferation, differentiation, and requirement for costimulation. ACTA ACUST UNITED AC 2007; 204:299-309. [PMID: 17261633 PMCID: PMC2118720 DOI: 10.1084/jem.20062319] [Citation(s) in RCA: 106] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
After a brief period of antigenic stimulation, T cells become committed to a program of autonomous expansion and differentiation. We investigated the role of antigen-specific T cell precursor frequency as a possible cell-extrinsic factor impacting T cell programming in a model of allogeneic tissue transplantation. Using an adoptive transfer system to incrementally raise the precursor frequency of antigen-specific CD8+ T cells, we found that donor-reactive T cells primed at low frequency exhibited increased cellular division, decreased development of multifunctional effector activity, and an increased requirement for CD28- and CD154-mediated costimulation relative to those primed at high frequency. The results demonstrated that recipients with low CD4+ and CD8+ donor-reactive T cell frequencies exhibited long-term skin graft survival upon CD28/CD154 blockade, whereas simultaneously raising the frequency of CD4+ T cells to ∼0.5% and CD8+ T cells to ∼5% precipitated graft rejection despite CD28/CD154 blockade. Antigenic rechallenge of equal numbers of cells stimulated at high or low frequency revealed that cells retained an imprint of the frequency at which they were primed. These results demonstrate a critical role for initial precursor frequency in determining the CD8+ T cell requirement for CD28- and CD154-mediated costimulatory signals during graft rejection.
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Affiliation(s)
- Mandy L Ford
- Department of Surgery and Emory Transplant Center, Emory University, Atlanta, GA 30322, USA
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20
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Inoue Y, Konieczny BT, Wagener ME, McKenzie AN, Lakkis FG. Failure to induce neonatal tolerance in mice that lack both IL-4 and IL-13 but not in those that lack IL-4 alone. J Immunol 2001; 167:1125-8. [PMID: 11441125 DOI: 10.4049/jimmunol.167.2.1125] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Current evidence suggests that neonatal tolerance to a foreign Ag is the consequence of IL-4-mediated Th2 immunity rather than the thymic deletion of Ag-specific T cells. Here, we addressed the role of IL-4 in neonatal tolerance by testing whether tolerance to a minor histocompatibility Ag can be induced in newborn mice that lack IL-4 (IL-4(-/-)). We found that IL-4 does not play a dominant role in the induction of neonatal tolerance as newborn female IL-4(-/-) mice could be readily tolerized to the H-Y male Ag. In contrast, mice that lack both IL-4 and IL-13 (IL-4(-/-)/IL-13(-/-)) were resistant to the induction of neonatal tolerance, and their splenocytes produced exaggerated amounts of IFN-gamma on rechallenge with the same Ag encountered during the neonatal period. These findings argue against the view that IL-4 alone is critical for the induction of neonatal tolerance and suggest that the combined actions of both IL-4 and IL-13 are essential for this process.
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Affiliation(s)
- Y Inoue
- Renal Division, Department of Medicine, Emory University and Veterans Affairs Medical Center, 1670 Clairmont Road, Atlanta, GA 30033, USA
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21
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Wagener ME, Konieczny BT, Dai Z, Ring GH, Lakkis FG. Alloantigen-driven T cell death mediated by Fas ligand and tumor necrosis factor-alpha is not essential for the induction of allograft acceptance. Transplantation 2000; 69:2428-32. [PMID: 10868653 DOI: 10.1097/00007890-200006150-00037] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Fas ligand (FasL)-Fas and tumor necrosis factor alpha (TNFalpha)-tumor necrosis factor receptor (TNFR) interactions regulate immune responses and contribute to self-tolerance by mediating antigen-driven T cell apoptosis. It is not known whether FasL and TNFalpha, expressed by the recipient's lymphoid or nonlymphoid cells, are essential for the apoptosis of alloreactive T lymphocytes and the induction of allograft acceptance. METHODS We compared the survival of fully allogeneic vascularized cardiac allografts between wild-type (wt) and FasL-mutant (gld) recipient mice. In addition, we studied cardiac allograft survival in gld mice injected with TNFalpha-neutralizing antibody. Allograft acceptance (graft survival >100 days) was induced by treating the recipients with CTLA4Ig, a recombinant fusion protein that blocks B7-CD28 T cell costimulation. In vivo alloantigen-driven apoptosis of mature CD4+ and CD8+ T lymphocytes was analyzed in mice repeatedly stimulated with allogeneic splenocytes. RESULTS We found that CTLA4Ig induces 100% long-term acceptance of cardiac allografts in wt and gld mice. Similarly, CTLA4Ig induced 100% allograft acceptance in gld recipients injected with TNFalpha-neutralizing antibody. In vivo alloantigen-driven apoptosis of mature CD4+ and CD8+ T cells was significantly reduced in gld mice and in wt mice treated with anti-TNFalpha antibody. However, neutralizing TNFalpha activity in gld mice failed to abrogate alloantigen-driven T cell apoptosis. CONCLUSIONS These data indicate that: (1) FasL and TNFalpha expression are not obligatory for the induction of long-term allograft acceptance by CTLA4Ig and (2) FasL- and TNFalpha-independent death pathways contribute to alloantigen-driven T cell apoptosis.
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Affiliation(s)
- M E Wagener
- The Carlos and Marguerite Mason Transplantation Research Center, Department of Medicine, Emory University and the Medical and Research Services, Veterans Affairs Medical Center, Atlanta, GA 30033, USA
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22
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Abstract
Emery-Dreifuss muscular dystrophy (EDMD) is the third most common X-linked muscular dystrophy. This disorder is characterized by childhood onset of early contractures, humeroperoneal muscle atrophy, and cardiac conduction abnormalities. Weakness is slowly progressive, but there is a broad spectrum of clinical severity. Patients and carriers are at risk of sudden death. Regular cardiac evaluation is mandatory to assess the risk of cardiac arrhythmias. Unique atrial pathology is seen at autopsy. The mutated gene in EDMD is localized to the long arm of the X chromosome. Mutations in the gene lead to abolished synthesis of the gene product, emerin. Emerin is localized to the nuclear membrane of skeletal, cardiac, and smooth muscle. The term Emery-Dreifuss syndrome describes patients who have the EDMD phenotype without X-linked inheritance. There is no treatment for the underlying disease, but early placement of pacemakers may be lifesaving.
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Affiliation(s)
- A S Zacharias
- Department of Neurology, Emory University School of Medicine, Atlanta, Georgia 30322, USA
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