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Aghbash PS, Rasizadeh R, Arefi V, Nahand JS, Baghi HB. Immune-checkpoint expression in antigen-presenting cells (APCs) of cytomegaloviruses infection after transplantation: as a diagnostic biomarker. Arch Microbiol 2023; 205:280. [PMID: 37430000 DOI: 10.1007/s00203-023-03623-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Revised: 06/26/2023] [Accepted: 06/30/2023] [Indexed: 07/12/2023]
Abstract
Cytomegalovirus (CMV), a member of the Herpesviridae family, mostly causes only slight feverish symptoms or can be asymptomatic in immunocompetent individuals. However, it is known to be particularly a significant cause of morbidity in immunocompromised patients, including transplant recipients, whose immune system has been weakened due to the consumption of immunosuppressor drugs. Therefore, the diagnosis of CMV infection after transplantation is crucial. New diagnostic methods for the quick detection of CMV have been developed as a result of understanding the clinical importance of invasive CMV. Antigen-presenting cells (APCs) and T cells are important components of the immune system and it may be possible to diagnose viral infections using immunological markers, such as lymphocytosis, cytotoxic T lymphocytes (CTL), and serum cytokine levels. Moreover, PD-1, CTLA 4, and TIGIT, which are expressed on certain T cells and antigen-presenting cells, are over-expressed during the infection. The assessment of CMV infection based on T cell and APC activity, and the expression of immunological checkpoints, can be helpful for the diagnosis of transplant patients at risk for CMV infection. In this review, we will investigate how immune checkpoints affect immune cells and how they impair organ transplantation after CMV infection.
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Affiliation(s)
- Parisa Shiri Aghbash
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Virology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reyhaneh Rasizadeh
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran
- Department of Virology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahid Arefi
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran
- Department of Microbiology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javid Sadri Nahand
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran
| | - Hossein Bannazadeh Baghi
- Immunology Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
- Department of Virology, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran.
- Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, 5166/15731, Iran.
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Dudreuilh C, Jarvis P, Beadle N, Pilecka I, Shaw O, Gardner L, Scottà C, Mamode N, Game DS, Sanchez-Fueyo A, Lombardi G, Learoyd A, Douiri A, Dorling A. Can regulatory T cells improve outcomes of sensitised patients after HLA-Ab incompatible renal transplantation: study protocol for the Phase IIa GAMECHANgER-1 trial. BMC Nephrol 2023; 24:117. [PMID: 37118685 PMCID: PMC10140710 DOI: 10.1186/s12882-023-03157-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 04/06/2023] [Indexed: 04/30/2023] Open
Abstract
BACKGROUND Kidney transplantation is the gold-standard treatment for patients with kidney failure. However, one-third of patients awaiting a kidney transplant are highly sensitized to human leukocyte antigens (HLA), resulting in an increased waiting time for a suitable kidney, more acute and chronic rejection, and a shorter graft survival compared to non-highly sensitised patients. Current standard immunosuppression protocols do not adequately suppress memory responses, and so alternative strategies are needed. Autologous polyclonally expanded regulatory T cells (Tregs) have been demonstrated to be safe in transplant settings and could be a potential alternative to modulate memory immune alloresponses. METHODS The aim of this trial is to determine whether adoptive transfer of autologous Tregs into HLA sensitised patients can suppress memory T and B cell responses against specific HLA antigens. This is a two-part, multi-centre, prospective clinical trial, comprising an observational phase (Part 1) aiming to identify patients with unregulated cellular memory responses to HLA (Pure HLA Proteins) followed by an interventional phase (Part 2). The first 9 patients identified as being eligible in Part 1 will undergo baseline immune monitoring for 2 months to inform statistical analysis of the primary endpoint. Part 2 is an adaptive, open labelled trial based on Simon's two-stage design, with 21 patients receiving Good Manufacturing Practice (GMP)-grade polyclonally expanded Tregs to a dose of 5-10 × 106 cells/kg body weight. The primary EP is suppression of in vitro memory responses for 2 months post-infusion. 12 patients will receive treatment in stage 1 of Part 2, and 9 patients will receive treatment in stage 2 of Part 2 if ≥ 50% patients pass the primary EP in stage 1. DISCUSSION This is a prospective study aiming to identify patients with unregulated cellular memory responses to Pure HLA Proteins and determine baseline variation in these patterns of response. Part 2 will be an adaptive phase IIa clinical trial with 21 patients receiving a single infusion of GMP-grade polyclonally expanded Tregs in two stages. It remains to be demonstrated that modulating memory alloresponses clinically using Treg therapy is achievable. TRIAL REGISTRATION EudraCT Number: 2021-001,664-23. REC Number: 21/SC/0253. Trial registration number ISRCTN14582152.
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Affiliation(s)
- C Dudreuilh
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK.
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK.
| | - P Jarvis
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - N Beadle
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - I Pilecka
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Clinical Trials Unit, King's College London, London, UK
| | - O Shaw
- Guy's and St Thomas's Hospital Trust, London, UK
| | - L Gardner
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - C Scottà
- Peter Gorer Department of Immunobiology, King's College London, London, UK
| | - N Mamode
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK
| | - D S Game
- Department of Transplantation, Guys and St, Thomas's Hospital NHS Trust, London, UK
| | - A Sanchez-Fueyo
- Institute of Liver Studies, King's College London University and King's College Hospital, London, UK
| | - G Lombardi
- Peter Gorer Department of Immunobiology, King's College London, London, UK
| | - A Learoyd
- School of Population Health and Environmental Sciences, King's College London, London, UK
| | - A Douiri
- School of Population Health and Environmental Sciences, King's College London, London, UK
| | - A Dorling
- Centre for Nephrology, Urology and Transplantation, Department of Inflammation Biology, School of Immunology and Microbial Sciences, King's College London & NIHR Biomedical Research Centre-Transplant Theme, Guy's Hospital, Great Maze Pond, London, SE1 9RT, UK
- Centre for Nephrology, Urology and Transplantation, School of Immunology and Microbial Sciences, King's College London, London, UK
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Mederacke YS, Nienen M, Jarek M, Geffers R, Hupa-Breier K, Babel N, Reinke P, Mederacke I, Vondran FWR, Jonigk D, Wedemeyer H, Jaeckel E. T cell receptor repertoires within liver allografts are different to those in the peripheral blood. J Hepatol 2021; 74:1167-1175. [PMID: 33347951 DOI: 10.1016/j.jhep.2020.12.014] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 12/08/2020] [Accepted: 12/10/2020] [Indexed: 12/04/2022]
Abstract
BACKGROUND & AIMS T cells are the main mediators of allogeneic immune responses. Specific T cell clones can be tracked by their unique T cell receptor (TCR), but specificity and function remain elusive and have not been investigated in human liver biopsies thus far. METHODS TCR repertoire analysis of CD4+, CD8+, and regulatory T cells of the peripheral blood and liver graft was performed in 7 liver transplant recipients with either stable course (non-rejector, NR), subclinical cellular rejection (SCR), or acute cellular rejection (ACR) during an observation period from pre-transplant to 6 years post-transplant. Furthermore, donor-reactive T cells, identified by their expression of CD154 and glycoprotein A repetitions predominant (GARP) after allogeneic activation, were tracked longitudinally in peripheral blood and within the liver allograft. RESULTS Although overall clonality of the TCR repertoire did not increase in peripheral blood after liver transplantation, clonality of donor-reactive CD4+ and regulatory T cells increased and these clones accumulated within the liver graft. Surprisingly, the TCR repertoires between the liver graft and the periphery were distinct and showed only limited overlap. Notably, during ACR, TCR repertoires aligned suggesting either graft-specific homing or release of activated T cells from the graft. CONCLUSIONS This is the first study comparing TCR repertoires between liver grafts and blood in patients with NR, SCR, and ACR. Moreover, we attribute specificity and function to a subgroup of intragraft T cell populations. Given the limited overlap between peripheral blood and intragraft repertoires, future studies investigating function and specificities of T cells after liver transplantation should focus on the intragraft immune response. LAY SUMMARY In solid organ transplantation, T cells are key mediators of the recipient's immune response directed at the transplanted organ. In our study, we characterised the T cell repertoire in a cohort of 7 liver transplant recipients. We demonstrate that donor-specific T cells expand clonally and accumulate in the transplanted liver. Moreover, we show that the composition of T cells in peripheral blood differs from the T cells in the liver allograft, only aligning in the context of acute cellular rejection but not in normal graft or subclinical cellular rejection. This indicates that the intragraft immune response is not mirrored in the peripheral blood. Our findings clarify the importance of protocol liver biopsies in identifying intragraft immune responses for future investigations of allo-directed immune responses.
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Affiliation(s)
- Young-Seon Mederacke
- Department of Gastroenterology, Hepatology & Endocrinology, Hannover Medical School, Hannover, Germany.
| | - Mikalai Nienen
- Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin-Brandenburg, Berlin, Germany; Labor Berlin-Charité Vivantes GmbH, Berlin, Germany
| | - Michael Jarek
- Department of Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Robert Geffers
- Department of Genome Analytics, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Katharina Hupa-Breier
- Department of Gastroenterology, Hepatology & Endocrinology, Hannover Medical School, Hannover, Germany
| | - Nina Babel
- Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin-Brandenburg, Berlin, Germany; Medical Department I, University Hospital of the Ruhr-University Bochum, Herne, Germany
| | - Petra Reinke
- Center for Regenerative Therapies, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH), Berlin-Brandenburg, Berlin, Germany; Center for Advanced Therapies, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health (BIH) Berlin-Brandenburg, Berlin, Germany
| | - Ingmar Mederacke
- Department of Gastroenterology, Hepatology & Endocrinology, Hannover Medical School, Hannover, Germany
| | | | - Danny Jonigk
- Institute for Pathology, Hannover Medical School, Hannover, Germany
| | - Heiner Wedemeyer
- Department of Gastroenterology, Hepatology & Endocrinology, Hannover Medical School, Hannover, Germany
| | - Elmar Jaeckel
- Department of Gastroenterology, Hepatology & Endocrinology, Hannover Medical School, Hannover, Germany.
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Shi Y, Lu Y, Zhu C, Luo Z, Li X, Liu Y, Jiang M, Liu X, Luo L, Du Y, You J. Targeted regulation of lymphocytic ER stress response with an overall immunosuppression to alleviate allograft rejection. Biomaterials 2021; 272:120757. [PMID: 33798960 DOI: 10.1016/j.biomaterials.2021.120757] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 03/05/2021] [Accepted: 03/12/2021] [Indexed: 12/20/2022]
Abstract
Transplantation is the most effective, and sometimes the only resort for end-stage organ failure. However, allogeneic graft suffers greatly from lymphocyte-mediated immunorejection, which bears close relationship with a hyperactivation of endoplasmic reticulum (ER) stress response in host lymphocytes, especially in CD8+ T cells (T-8). Therefore, regulating lymphocytic ER unfolded protein response (UPR) might be a potential therapeutic breakthrough in alleviating graft rejection. Here, ER-targetable liposome is prepared via the surface modification of ER-targeting peptide (Pardaxin), which efficiently loads and directly delivers small molecule inhibitor of UPR sensor IRE1α into the ER of lymphocytes, inducing a systemic immunosuppression that facilitates tumorigenesis and metastasis in the tumor inoculation challenge in vivo. And in vitro, a stage-differential dependency of IRE1α in the phase transition of T-8 is identified. Specifically, inhibiting IRE1α at the early responding stages of T-8, especially at the activation phase, results in a shrunk proliferation, impaired effector function, and limited memory commitment, which might contribute centrally to the induced overall immunosuppression. Based on this, a classical acute rejection model, murine full-thickness trunk skin allograft that primary arises from the hyperactivity of T-lymphocyte, is used. Results suggest that lymphocytic IRE1α inactivation attenuates transplant rejection and prolongs graft survival, with a limited effector function and memory commitment of host T-8. Moreover, an even higher immunosuppressive effect is obtained when IRE1α inhibition is used in combination with immunosuppressant tacrolimus (FK506), which might owe to a synergistic regulation of inflammatory transcription factors. These findings provide a deeper insight into the biological polarization and stress response of lymphocytes, which might guide the future development of allogeneic transplantation.
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Affiliation(s)
- Yingying Shi
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Yichao Lu
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Chunqi Zhu
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Zhenyu Luo
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Xiang Li
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Yu Liu
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Mengshi Jiang
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Xu Liu
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Lihua Luo
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Yongzhong Du
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China
| | - Jian You
- College of Pharmaceutical Sciences, Zhejiang University, 866 Yuhangtang Road, Hangzhou, Zhejiang, 310058, PR China.
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Eskandari SK, Sulkaj I, Melo MB, Li N, Allos H, Alhaddad JB, Kollar B, Borges TJ, Eskandari AS, Zinter MA, Cai S, Assaker JP, Choi JY, Al Dulaijan BS, Mansouri A, Haik Y, Tannous BA, van Son WJ, Leuvenink HGD, Pomahac B, Riella LV, Tang L, Seelen MAJ, Irvine DJ, Azzi JR. Regulatory T cells engineered with TCR signaling-responsive IL-2 nanogels suppress alloimmunity in sites of antigen encounter. Sci Transl Med 2020; 12:eaaw4744. [PMID: 33177180 PMCID: PMC8519505 DOI: 10.1126/scitranslmed.aaw4744] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2019] [Revised: 06/03/2020] [Accepted: 09/03/2020] [Indexed: 07/30/2023]
Abstract
Adoptive cell transfer of ex vivo expanded regulatory T cells (Tregs) has shown immense potential in animal models of auto- and alloimmunity. However, the effective translation of such Treg therapies to the clinic has been slow. Because Treg homeostasis is known to require continuous T cell receptor (TCR) ligation and exogenous interleukin-2 (IL-2), some investigators have explored the use of low-dose IL-2 injections to increase endogenous Treg responses. Systemic IL-2 immunotherapy, however, can also lead to the activation of cytotoxic T lymphocytes and natural killer cells, causing adverse therapeutic outcomes. Here, we describe a drug delivery platform, which can be engineered to autostimulate Tregs with IL-2 in response to TCR-dependent activation, and thus activate these cells in sites of antigen encounter. To this end, protein nanogels (NGs) were synthesized with cleavable bis(N-hydroxysuccinimide) cross-linkers and IL-2/Fc fusion (IL-2) proteins to form particles that release IL-2 under reducing conditions, as found at the surface of T cells receiving stimulation through the TCR. Tregs surface-conjugated with IL-2 NGs were found to have preferential, allograft-protective effects relative to unmodified Tregs or Tregs stimulated with systemic IL-2. We demonstrate that murine and human NG-modified Tregs carrying an IL-2 cargo perform better than conventional Tregs in suppressing alloimmunity in murine and humanized mouse allotransplantation models. In all, the technology presented in this study has the potential to improve Treg transfer therapy by enabling the regulated spatiotemporal provision of IL-2 to antigen-primed Tregs.
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Affiliation(s)
- Siawosh K Eskandari
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Division of Nephrology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, Netherlands
| | - Ina Sulkaj
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Mariane B Melo
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Na Li
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Hazim Allos
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Juliano B Alhaddad
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Branislav Kollar
- Division of Plastic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Thiago J Borges
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Transplantation Sciences, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Arach S Eskandari
- Department of Electrical Engineering, Delft University of Technology, 2628 CD Delft, Netherlands
| | - Max A Zinter
- Experimental Therapeutics and Molecular Imaging Unit, Department of Neurology, Neuro-Oncology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
| | - Songjie Cai
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Jean Pierre Assaker
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - John Y Choi
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Basmah S Al Dulaijan
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Amr Mansouri
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Yousef Haik
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Bakhos A Tannous
- Experimental Therapeutics and Molecular Imaging Unit, Department of Neurology, Neuro-Oncology Division, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
| | - Willem J van Son
- Division of Nephrology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, Netherlands
| | - Henri G D Leuvenink
- Department of Surgery, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, Netherlands
| | - Bohdan Pomahac
- Division of Plastic Surgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Leonardo V Riella
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA
- Center for Transplantation Sciences, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA
| | - Li Tang
- Institute of Bioengineering, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
- Institute of Materials Science and Engineering, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| | - Marc A J Seelen
- Division of Nephrology, University Medical Center Groningen, University of Groningen, 9713 GZ Groningen, Netherlands
| | - Darrell J Irvine
- Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, Cambridge, MA 02142, USA.
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
- Ragon Institute of Massachusetts General Hospital, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
- Howard Hughes Medical Institute, Chevy Chase, MD 20815, USA
| | - Jamil R Azzi
- Transplantation Research Center, Brigham and Women's Hospital, Harvard Medical School, Boston, MA 02115, USA.
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Gliwiński M, Piotrowska M, Iwaszkiewicz-Grześ D, Urban-Wójciuk Z, Trzonkowski P. Therapy with CD4 +CD25 + T regulatory cells - should we be afraid of cancer? Contemp Oncol (Pozn) 2019; 23:1-6. [PMID: 31061630 PMCID: PMC6500397 DOI: 10.5114/wo.2019.84110] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 03/24/2019] [Indexed: 12/27/2022] Open
Abstract
This review focuses on the role of regulatory T cells (Tregs) in the process of carcinogenesis. The controversy of this issue arose due to the increasing therapeutic use of Tregs in humans (inter alia, in the treatment of autoimmune diseases). It is mainly due to potential dangers related to immunosuppressive activity of these cells, especially regarding cancer. The natural function of regulatory T cells (which is the suppression of excessive activity of the immune system) is purportedly linked to an increased risk of cancer initiation. This work brings together and summarizes the most important reports of researchers dealing with this problem and attempts to explain doubts and fears related to Tregs and their uncertain connection with cancer initiation and progression. It is clearly shown that regulatory T cells are associated with acceleration of existing tumors (they are attracted by microenvironments created by cancer cells) but cannot initiate them on their own.
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Affiliation(s)
- Mateusz Gliwiński
- Department of Medical Immunology, Medical University of Gdansk, Gdansk, Poland
| | | | | | - Zuzanna Urban-Wójciuk
- International Centre for Cancer Vaccine Science, University of Gdansk, Gdansk, Poland
| | - Piotr Trzonkowski
- Department of Medical Immunology, Medical University of Gdansk, Gdansk, Poland
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Gupta PK, McIntosh CM, Chong AS, Alegre ML. The pursuit of transplantation tolerance: new mechanistic insights. Cell Mol Immunol 2019; 16:324-333. [PMID: 30760917 DOI: 10.1038/s41423-019-0203-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 01/17/2019] [Indexed: 12/11/2022] Open
Abstract
Donor-specific transplantation tolerance that enables weaning from immunosuppressive drugs but retains immune competence to non-graft antigens has been a lasting pursuit since the discovery of neonatal tolerance. More recently, efforts have been devoted not only to understanding how transplantation tolerance can be induced but also the mechanisms necessary to maintain it as well as how inflammatory exposure challenges its durability. This review focuses on recent advances regarding key peripheral mechanisms of T cell tolerance, with the underlying hypothesis that a combination of several of these mechanisms may afford a more robust and durable tolerance and that a better understanding of these individual pathways may permit longitudinal tracking of tolerance following clinical transplantation to serve as biomarkers. This review may enable a personalized assessment of the degree of tolerance in individual patients and the opportunity to strengthen the robustness of peripheral tolerance.
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Affiliation(s)
- Pawan K Gupta
- Department of Medicine, The University of Chicago, Chicago, IL, 60637, USA
| | | | - Anita S Chong
- Department of Surgery, The University of Chicago, Chicago, IL, 60637, USA
| | - Maria-Luisa Alegre
- Department of Medicine, The University of Chicago, Chicago, IL, 60637, USA.
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Cheng HY, Tay SKL, Wen CJ, Lin CF, Wang AYL, Shih LY, Liu SC, Kobayashi E, Lin CH, Wei FC. Bioimaging of alloantigen-stimulated regulatory T cells in rat vascularized composite allotransplantation. PLoS One 2018; 13:e0203624. [PMID: 30192879 PMCID: PMC6128578 DOI: 10.1371/journal.pone.0203624] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2018] [Accepted: 08/23/2018] [Indexed: 11/18/2022] Open
Abstract
Background Tipping the balance toward regulatory T cells (Tregs) through adoptive cell therapy has shown promise to induce transplantation tolerance. Although such strategy has been explored in many mice organ transplantation studies, less knowledge was available in rat systems. Furthermore, the behaviors of the transferred cells have not been well studied in real-time fashion. Methods Tregs from naïve LEW rats were purified in two steps with the autoMACS system. Immunosuppression potential of these cells was examined with mixed lymphocyte reaction. Following stimulation by the alloantigen in vitro, the purified Tregs were infused into the recipients of vascularized composite allotransplantation (VCA). Secondary allogeneic skin grafting challenge was performed on the recipients with long-term survived VCA. Live optical imaging was performed to track luciferase-expressing Tregs following infusion to the VCA recipients. Expression of relevant molecules was studied by flow cytometry or quantitative RT-PCR. Results Rat Tregs were enriched following two-step cell sorting and showed immunosuppressive capacity. Upon infusion into the VCA recipients that have been treated with antilymphocyte serum and short-term Cyclosporin A, the antigen-stimulated Tregs significantly prolonged VCA survival and induced donor-specific tolerance. Tracking of the infused bioluminescent Tregs showed their specific homing to lymph nodes, and then to the VCAs. Following secondary skin grafting, Tregs specifically gathered at the donor-derived skin that was not rejected by the recipient. The in vivo migratory pattern coincided with the altered expression of cell surface molecules of CD62L, CD103, CD134, and CD278, following donor-antigen stimulation. Elevated expression of CCR4 and CCL22 in allograft may also participate in recruiting Tregs for maintenance of VCA survival and promoting donor-specific tolerance. Conclusion Sorted Tregs induced donor-specific tolerance to VCA in rats. Live cell tracking demonstrated that activated CD4+CD25+FoxP3+ Tregs targeted primarily to the lymph nodes and VCA. The Tregs migrated to the secondary grafted donor skin and contributed to the maintenance of donor-specific tolerance. These behaviors were associated with phenotypic changes induced by donor antigen stimulation. Increased expression of CCR4 and CCL22 in VCA skin may also be relevant.
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Affiliation(s)
- Hui-Yun Cheng
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
- * E-mail:
| | - Sheri K. L. Tay
- Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
- Canniesburn Plastic Surgery Unit, Glasgow Royal Infirmary, Glasgow, United Kingdom
| | - Chih-Jen Wen
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Chih-Fan Lin
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Aline Yen-Ling Wang
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Ling-Yi Shih
- Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Shiao-Chin Liu
- Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Eiji Kobayashi
- Department of Organ Fabrication, Keio University School of Medicine, Tokyo, Japan
| | - Cheng-Hung Lin
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
- Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
| | - Fu-Chan Wei
- Center for Vascularized Composite Allotransplantation, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
- Department of Plastic and Reconstructive Surgery, Linkou Chang Gung Memorial Hospital, Gueishan, Taoyuan, Taiwan
- School of Medicine, Chang Gung University, Gueishan, Taoyuan, Taiwan
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10
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Young JS, Yin D, Vannier AGL, Alegre ML, Chong AS. Equal Expansion of Endogenous Transplant-Specific Regulatory T Cell and Recruitment Into the Allograft During Rejection and Tolerance. Front Immunol 2018; 9:1385. [PMID: 29973932 PMCID: PMC6020780 DOI: 10.3389/fimmu.2018.01385] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/04/2018] [Indexed: 01/07/2023] Open
Abstract
Despite numerous advances in the definition of a role for regulatory T cells (Tregs) in facilitating experimental transplantation tolerance, and ongoing clinical trials for Treg-based therapies, critical issues related to the optimum dosage, antigen-specificity, and Treg-friendly adjunct immunosuppressants remain incompletely resolved. In this study, we used a tractable approach of MHC tetramers and flow cytometry to define the fate of conventional (Tconvs) and Tregs CD4+ T cells that recognize donor 2W antigens presented by I-Ab on donor and recipient antigen-presenting cells (APCs) in a mouse cardiac allograft transplant model. Our study shows that these endogenous, donor-reactive Tregs comparably accumulate in the spleens of recipients undergoing acute rejection or exhibiting costimulation blockade-induced tolerance. Importantly, this expansion was not detected when analyzing bulk splenic Tregs. Systemically, the distinguishing feature between tolerance and rejection was the inhibition of donor-reactive conventional T cell (Tconv) expansion in tolerance, translating into increased percentages of splenic FoxP3+ Tregs within the 2W:I-Ab CD4+ T cell subset compared to rejection (~35 vs. <5% in tolerance vs. rejection). We further observed that continuous administration of rapamycin, cyclosporine A, or CTLA4-Ig did not facilitate donor-specific Treg expansion, while all three drugs inhibited Tconv expansion. Finally, donor-specific Tregs accumulated comparably in rejecting tolerant allografts, whereas tolerant grafts harbored <10% of the donor-specific Tconv numbers observed in rejecting allografts. Thus, ~80% of 2W:I-Ab CD4+ T cells in tolerant allografts expressed FoxP3+ compared to ≤10% in rejecting allografts. A similar, albeit lesser, enrichment was observed with bulk graft-infiltrating CD4+ cells, where ~30% were FoxP3+ in tolerant allografts, compared to ≤10% in rejecting allografts. Finally, we assessed that the phenotype of 2W:I-Ab Tregs and observed that the percentages of cells expressing neuropilin-1 and CD73 were significantly higher in tolerance compared to rejection, suggesting that these Tregs may be functionally distinct. Collectively, the analysis of donor-reactive, but not of bulk, Tconvs and Tregs reveal a systemic signature of tolerance that is stable and congruent with the signature within tolerant allografts. Our data also underscore the importance of limiting Tconv expansion for high donor-specific Tregs:Tconv ratios to be successfully attained in transplantation tolerance.
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Affiliation(s)
- James S Young
- Department of Surgery, The University of Chicago, Chicago, IL, United States
| | - Dengping Yin
- Department of Surgery, The University of Chicago, Chicago, IL, United States
| | | | - Maria-Luisa Alegre
- Department of Medicine, The University of Chicago, Chicago, IL, United States
| | - Anita S Chong
- Department of Surgery, The University of Chicago, Chicago, IL, United States
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11
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Zaitsu M, Issa F, Hester J, Vanhove B, Wood KJ. Selective blockade of CD28 on human T cells facilitates regulation of alloimmune responses. JCI Insight 2017; 2:89381. [PMID: 28978798 DOI: 10.1172/jci.insight.89381] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Accepted: 08/29/2017] [Indexed: 01/05/2023] Open
Abstract
T cells are central to the detrimental alloresponses that develop in autoimmunity and transplantation, with CD28 costimulatory signals being key to T cell activation and proliferation. CTLA4-Ig molecules that bind CD80/86 and inhibit CD28 costimulation offer an alternative immunosuppressive treatment, free from some of the chronic toxicities associated with calcineurin inhibition. However, CD80/86 blockade by CTLA4-Ig also results in the loss of coinhibitory CTLA4 signals that are critical to the regulation of T cell activation. Here, we show that a nonactivating monovalent anti-CD28 that spares CTLA4 signaling is an effective immunosuppressant in a clinically relevant humanized mouse transplant model. We demonstrate that selective CD28 blockade prolongs human skin allograft survival through a mechanism that includes a reduction in the cellular graft infiltrate. Critically, selective CD28 blockade promotes Treg function in vivo and synergizes with adoptive Treg therapy to promote transplant survival. In contrast to CTLA4-Ig treatment, selective CD28 blockade promotes regulation of alloimmune responses and facilitates Treg-based cellular therapy.
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Affiliation(s)
- Masaaki Zaitsu
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Headington, Oxford, United Kingdom.,Department of Gastroenterological Surgery I, Hokkaido University Graduate School of Medicine, Sapporo, Japan
| | - Fadi Issa
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Headington, Oxford, United Kingdom
| | - Joanna Hester
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Headington, Oxford, United Kingdom
| | - Bernard Vanhove
- Centre de Recherche en Transplantation et Immunologie UMR 1064, INSERM, Université de Nantes, Nantes, France.,Institut de Transplantation Urologie Néphrologie (ITUN), CHU Nantes, Nantes, France.,OSE Immunotherapeutics, Nantes, France
| | - Kathryn J Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Headington, Oxford, United Kingdom
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12
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Zwang NA, Leventhal JR. Cell Therapy in Kidney Transplantation: Focus on Regulatory T Cells. J Am Soc Nephrol 2017; 28:1960-1972. [PMID: 28465379 DOI: 10.1681/asn.2016111206] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Renal transplantation is the renal replacement modality of choice for suitable candidates with advanced CKD or ESRD. Prevention of rejection, however, requires treatment with nonspecific pharmacologic immunosuppressants that carry both systemic and nephrologic toxicities. Use of a patient's own suppressive regulatory T cells (Tregs) is an attractive biologic approach to reduce this burden. Here, we review the immunologic underpinnings of Treg therapy and technical challenges to developing successful cell therapy. These issues include the selection of appropriate Treg subsets, ex vivo Treg expansion approaches, how many Tregs to administer and when, and how to care for patients after Treg administration.
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Affiliation(s)
| | - Joseph R Leventhal
- Comprehensive Transplant Center, Northwestern Memorial Hospital, Chicago, Illinois
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13
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Regulatory immune cells and functions in autoimmunity and transplantation immunology. Autoimmun Rev 2017; 16:435-444. [DOI: 10.1016/j.autrev.2017.03.011] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Accepted: 01/26/2017] [Indexed: 12/15/2022]
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14
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Hall BM, Tran GT, Robinson CM, Hodgkinson SJ. Induction of antigen specific CD4+CD25+Foxp3+T regulatory cells from naïve natural thymic derived T regulatory cells. Int Immunopharmacol 2015; 28:875-86. [DOI: 10.1016/j.intimp.2015.03.049] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2015] [Accepted: 03/28/2015] [Indexed: 12/14/2022]
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15
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Lin K, Chen S, Chen G. Role of Memory T Cells and Perspectives for Intervention in Organ Transplantation. Front Immunol 2015; 6:473. [PMID: 26441978 PMCID: PMC4568416 DOI: 10.3389/fimmu.2015.00473] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Accepted: 08/31/2015] [Indexed: 12/12/2022] Open
Abstract
Memory T cells are necessary for protective immunity against invading pathogens, especially under conditions of immunosuppression. However, their presence also threatens transplant survival, making transplantation a great challenge. Significant progress has been achieved in recent years in advancing our understanding of the role that memory T cells play in transplantation. This review focuses on the latest advances in our understanding of the involvement of memory T cells in graft rejection and transplant tolerance and discusses potential strategies for targeting memory T cells in order to minimize allograft rejection and optimize clinical outcomes.
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Affiliation(s)
- Kailin Lin
- Institute of Organ Transplantation, Tongji Hospital, Huazhong University of Science and Technology , Wuhan , China
| | - Song Chen
- Institute of Organ Transplantation, Tongji Hospital, Huazhong University of Science and Technology , Wuhan , China ; Key Laboratory of Organ Transplantation, Ministry of Education , Wuhan , China ; Key Laboratory of Organ Transplantation, Ministry of Public Health , Wuhan , China
| | - Gang Chen
- Institute of Organ Transplantation, Tongji Hospital, Huazhong University of Science and Technology , Wuhan , China ; Key Laboratory of Organ Transplantation, Ministry of Education , Wuhan , China ; Key Laboratory of Organ Transplantation, Ministry of Public Health , Wuhan , China
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16
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Tang Q, Kang SM. Interpretation of transplant biopsies and immune responses following Treg cell therapy. Curr Opin Organ Transplant 2015; 19:616-20. [PMID: 25313874 DOI: 10.1097/mot.0000000000000132] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
PURPOSE OF REVIEW Regulatory T cells (Treg) are now well established as vital participants in maintaining self-tolerance and preventing autoimmunity. Tregs have already been shown to be effective in preventing graft-versus-host disease in clinical bone marrow transplantation, and numerous animal studies have suggested a therapeutic role for Treg in solid organ transplantation. Recent advances in Treg isolation and expansion have the field poised to perform trials of therapeutic Treg infusion in solid organ transplantation worldwide. An important component of these trials will be the detection of infused cells and the assessment of Treg activity after infusion. RECENT FINDINGS Several animal studies have demonstrated that infused Treg migrate to transplanted tissue in the early period after transplantation. This finding has important implications for the interpretation of biopsy results in human trials. Recent refinements in Treg identification, quantification, and functional assays will be discussed in the context of immune monitoring. SUMMARY Understanding the migration/localization and persistence of infused Treg into transplanted tissues as well as how they impact the peripheral immune response will be critical to the interpretation of early Treg trials.
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Affiliation(s)
- Qizhi Tang
- Department of Surgery, University of California, San Francisco, California, USA
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17
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Juvet SC, Whatcott AG, Bushell AR, Wood KJ. Harnessing regulatory T cells for clinical use in transplantation: the end of the beginning. Am J Transplant 2014; 14:750-63. [PMID: 24592900 DOI: 10.1111/ajt.12647] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 12/19/2013] [Accepted: 12/19/2013] [Indexed: 01/25/2023]
Abstract
Owing to the adverse effects of immunosuppression and an inability to prevent chronic rejection, there is a pressing need for alternative strategies to control alloimmunity. In three decades, regulatory T cells (Tregs) have evolved from a hypothetical mediator of adoptively transferred tolerance to a well-defined population that can be expanded ex vivo and returned safely to patients in clinical trials. Herein, we review the historical developments that have permitted these advances and the current status of clinical trials examining Tregs as a cellular therapy in transplantation. We conclude by discussing the critical unanswered questions that face this field in the coming years.
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Affiliation(s)
- S C Juvet
- Nuffield Department of Surgical Sciences, Transplantation Research Immunology Group, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
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18
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Su Y, Jevnikar AM, Huang X, Lian D, Zhang ZX. Spi6 protects alloreactive CD4(+) but not CD8 (+) memory T cell from granzyme B attack by double-negative T regulatory cell. Am J Transplant 2014; 14:580-93. [PMID: 24730048 DOI: 10.1111/ajt.12614] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Memory T (Tm) cells pose a major barrier to long-term transplant survival. Whether regulatory T cells (Tregs)can control them remains poorly defined. Previously,we established that double-negative (DN) Tregs suppress effector T (Teff) cells. Here, we demonstrate that DNTregs effectively suppress CD4+/CD8+Teff and CD8+Tm but not CD4+Tm cells, whereas the suppression on CD8+Tm is abrogated by perforin (PFN) deficiency in DNTregs. Consistently, in a BALB/c to B6-Rag1-/-skin transplantation, transfer of DN Tregs suppressed the rejection mediated by CD4þ/CD8+Teff and CD8+Tmcells (76.0±4.9, 87.5±5.0 and 63.0±4.7 days, respectively)but not CD4þTmcells (25.3±1.4 days). Both CD8þ effector memory T and central memory T compartments significantly reduced after DN Treg transfer. CD4+Tm highly expresses granzyme B (GzmB) inhibitor serine protease inhibitor-6 (Spi6). Spi6 deficiency renders CD4þTm susceptible to DN Treg suppression. In addition,transfer of WT DN Tregs, but not PFN-/-DN Tregs,inhibited the skin allograft rejection mediated by Spi6-/-CD4þTm(75.5±7.9 days). In conclusion, CD4+ and CD8+Tm cells differentially respond toDNTregs’ suppression.The GzmB resistance conferred by Spi6 in CD4þTm cells might hint at the physiological significance of Tmpersistence
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19
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Bright JD, Schultz HN, Byrne JA, Bright RK. Injection site and regulatory T cells influence durable vaccine-induced tumor immunity to an over-expressed self tumor associated antigen. Oncoimmunology 2013; 2:e25049. [PMID: 24073379 PMCID: PMC3782160 DOI: 10.4161/onci.25049] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2013] [Revised: 05/14/2013] [Accepted: 05/15/2013] [Indexed: 12/29/2022] Open
Abstract
Tumor protein D52 (D52) is constitutively expressed in healthy tissues and overexpressed in multiple cancers, including (but not limited to) breast, prostate and ovarian carcinomas. Although the normal functions of D52 are unknown, it is clear that increased D52 expression levels not only stimulate cell proliferation and metastasis, but also correlate with poor prognosis in a subset of breast cancer patients. The murine orthologs of D52 (mD52) shares 86% identity with its human counterpart (hD52) and mirrors hD52 expression patterns. The forced overexpression of mD52 induces anchorage-independent growth in vitro and promotes tumor formation as well as spontaneous metastasis in vivo. We have previously reported that the intramuscular administration of recombinant mD52 elicits immune responses capable of rejecting a challenge with tumor cells and preventing spontaneous metastasis only in 50% of mice. We hypothesized that mechanisms of peripheral tolerance dampen immune responses against mD52, thus limiting the protective effects of vaccination. To test this hypothesis, mice were depleted of CD25+ regulatory T cells (Tregs) and subcutaneously immunized with mD52 prior to a tumor challenge. The subcutaneous immunization failed to induce protective antitumor immunity unless accompanied by Treg depletion, which resulted in a rate of protection of 70% as compared with
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Affiliation(s)
- Jennifer D Bright
- Department of Immunology and Molecular Microbiology; Texas Tech University Health Sciences Center; Lubbock, TX USA
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20
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Noël G, Belghith M, Bélanger B, Leduc C, Daniel C. Direct Alloreactivity Is More Susceptible to Regulation by Natural Regulatory T Cells Than Indirect Alloreactivity. THE JOURNAL OF IMMUNOLOGY 2013; 190:3764-71. [DOI: 10.4049/jimmunol.1200190] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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21
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Vitova A, Kuffová L, Klaska IP, Holan V, Cornall RJ, Forrester JV. The high-risk corneal regraft model: a justification for tissue matching in humans. Transpl Int 2013; 26:453-61. [PMID: 23398177 DOI: 10.1111/tri.12055] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Revised: 06/18/2012] [Accepted: 12/14/2012] [Indexed: 12/17/2022]
Abstract
Models of high-risk corneal graft rejection involve neovascularization induced via innate immune responses, e.g., suture-mediated trauma. We describe a model of high-risk corneal graft rejection using corneal graft donor-recipient pairing based on a single-antigen disparity. Donor corneas from transgenic mice on B10.BR (H-2k ) background, in which hen-egg lysozyme (HEL) as a membrane-bound antigen (mHEL) was expressed under the major histocompatibility complex (MHC) class I promoter (KLK-mHEL, H-2k), were transplanted into wild type B10.BR recipient mice. Unmanipulated wild type recipient mice rejected KLK-mHEL grafts (39%) slowly over 50-60 days. Graft rejection incidence was maximized (100%) and tempo accelerated (27 days) by priming with HEL-pulsed syngeneic dendritic cells and less so by increasing T-cell precursor frequency. Rejection also reached maximum levels (100%) and tempo (3-8 days) when mice which had rejected a first graft ('rejectors') were regrafted, and was associated with induction of HEL-specific memory T cells. In contrast, 'acceptors' rejected a second graft at rates and tempo similar to naïve mice. These data reveal the importance of (i) donor MHC antigens as alloantigens for indirect recognition, (ii) alloantigen-specific memory in high-risk graft rejection involving regrafts, and (iii) suggest a role for tissue matching in human corneal graft to avoid sensitization to donor MHC antigens.
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Affiliation(s)
- Andrea Vitova
- Section of Immunology and Infection, Division of Applied Medicine, University of Aberdeen, Aberdeen, UK
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22
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Wood K, Shankar S, Mittal S. Concepts and challenges in organ transplantation. Clin Immunol 2013. [DOI: 10.1016/b978-0-7234-3691-1.00095-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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23
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Issa F, Hester J, Milward K, Wood KJ. Homing of regulatory T cells to human skin is important for the prevention of alloimmune-mediated pathology in an in vivo cellular therapy model. PLoS One 2012; 7:e53331. [PMID: 23300911 PMCID: PMC3534052 DOI: 10.1371/journal.pone.0053331] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2012] [Accepted: 11/28/2012] [Indexed: 11/24/2022] Open
Abstract
Regulatory T cell (Treg) therapy for immune modulation is a promising therapeutic strategy for the treatment and prevention of autoimmune disease and graft-versus-host disease (GvHD) after bone marrow transplantation. However, Treg are heterogeneous and express a variety of chemokine receptor molecules. The optimal subpopulation of Treg for therapeutic use may vary according to the pathological target. Indeed, clinical trials of Treg for the prevention of GvHD where the skin is a major target of the anti-host response have employed Treg derived from a variety of different sources. We postulated that for the effective treatment of GvHD-related skin pathology, Treg must be able to migrate to skin in order to regulate local alloimmune responses efficiently. To test the hypothesis that different populations of Treg display distinct efficacy in vivo based on their expression of tissue-specific homing molecules, we evaluated the activity of human Treg derived from two disparate sources in a model of human skin transplantation. Treg were derived from adult blood or cord blood and expanded in vitro. While Treg from both sources displayed similar in vitro suppressive efficacy, they exhibited marked differences in the expression of skin homing molecules. Importantly, only adult-derived Treg were able to prevent alloimmune-mediated human skin destruction in vivo, by virtue of their improved migration to skin. The presence of Treg within the skin was sufficient to prevent its alloimmune-mediated destruction. Additionally, Treg expressing the skin homing cutaneous lymphocyte antigen (CLA) were more efficient at preventing skin destruction than their CLA-deficient counterparts. Our findings highlight the importance of the careful selection of an effective subpopulation of Treg for clinical use according to the pathology of interest.
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Affiliation(s)
- Fadi Issa
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford
| | - Joanna Hester
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford
| | - Kate Milward
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford
| | - Kathryn J. Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford
- * E-mail:
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24
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Issa F, Robb RJ, Wood KJ. The where and when of T cell regulation in transplantation. Trends Immunol 2012; 34:107-13. [PMID: 23228885 DOI: 10.1016/j.it.2012.11.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Revised: 11/08/2012] [Accepted: 11/13/2012] [Indexed: 01/03/2023]
Abstract
Multiple cell types contribute to the peripheral regulation of T cell alloresponses in haematopoieitc cell transplantation (HCT) and solid organ transplantation (SOT). Of these, regulatory T cells (Tregs) are the principal players and have shown the greatest success in the therapeutic control of detrimental immune responses. Investigations into the induction, location, and mechanism of suppression utilised by Tregs to control alloreactive responses are ongoing. The activation and homing characteristics of Tregs are important to their regulatory capabilities, with activation and homing occurring in the same time and space as conventional T cells. This review discusses these characteristics and recent advances in the field as we move closer to the ultimate goal of utilising Tregs as treatment for allograft rejection and graft-versus-host disease (GvHD).
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Affiliation(s)
- Fadi Issa
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, UK
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25
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Wood KJ, Bushell A, Hester J. Regulatory immune cells in transplantation. Nat Rev Immunol 2012; 12:417-30. [DOI: 10.1038/nri3227] [Citation(s) in RCA: 340] [Impact Index Per Article: 28.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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26
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Mendieta-Zerón H. Developing immunologic tolerance for transplantation at the fetal stage. Immunotherapy 2012; 3:1499-512. [PMID: 22091685 DOI: 10.2217/imt.11.142] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Given the shortage of human organs for transplantation, the waiting lists are increasing annually and consequently so is the time and deaths during the wait. As most immune suppression therapy is not antigen specific and the risk of infection tends to increase, scientists are looking for new options for immunosuppression or immunotolerance. Tolerance induction would avoid the complications caused by immunosupressive drugs. As such, taking into account the experience with autoimmune diseases, one strategy could be immune modulation-induced changes in T-cell cytokine secretion or antigen therapy; however, most clinical trials have failed. Gene transfer of MHC genes across species may be used to induce tolerance to xenogenic solid organs. Other options are induction of central tolerance by the establishment of mixed chimerism through hematopoietic stem cell transplantation and the induction of 'operational tolerance' through immunodeviation involving dendritic or Tregs. I propose that, as the recognition and tolerance of proteins takes place in the thymus, this organ should be the main target for immunotolerance research protocols even as early as during the fetal development.
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Issa F, Chandrasekharan D, Wood KJ. Regulatory T cells as modulators of chronic allograft dysfunction. Curr Opin Immunol 2012; 23:648-54. [PMID: 21752619 DOI: 10.1016/j.coi.2011.06.005] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2011] [Accepted: 06/20/2011] [Indexed: 12/19/2022]
Abstract
Chronic allograft dysfunction (CAD) in solid organ transplantation is a principal cause of patient morbidity and late allograft loss. The pathogenesis of CAD is largely secondary to chronic damage by the adaptive immune system and long-term immunosuppression. Manipulating these factors may be possible with the use of regulatory T cells (Treg), which have the ability to suppress specific immune responses and therefore potentially remove the need for immunosuppressive drugs. Studies of CAD in experimental models have demonstrated the capacity for both mouse and human Treg cellular therapy to prevent the development of some manifestations of CAD. Furthermore, a role for Treg has been demonstrated in clinically tolerant transplant patients. Certain immunosuppressive therapies are also proving to be 'Treg friendly' and may be helpful in promoting Treg while maintaining other immunosuppressive activity. With this in mind, monitoring for biomarkers of operational tolerance with tailored immunosuppressive therapy or controlled weaning in conjunction with Treg cellular therapy may be a useful strategy to pursue.
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Affiliation(s)
- Fadi Issa
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, United Kingdom
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Abstract
T Regulatory cells (Treg) play an important role in the induction and maintenance of immunological tolerance to self and alloantigens. Recent findings in experimental transplant models have demonstrated that Treg can control acute and delayed allograft rejection. Preclinical attempts to use Treg as a cellular therapy have been successfully undertaken demonstrating the safety and feasibility of such treatment, suggesting that they have therapeutic potential.
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Affiliation(s)
- K J Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, United Kingdom.
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Sagoo P, Ali N, Garg G, Nestle FO, Lechler RI, Lombardi G. Human regulatory T cells with alloantigen specificity are more potent inhibitors of alloimmune skin graft damage than polyclonal regulatory T cells. Sci Transl Med 2011; 3:83ra42. [PMID: 21593402 DOI: 10.1126/scitranslmed.3002076] [Citation(s) in RCA: 287] [Impact Index Per Article: 22.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Graft rejection by the immune system is a major cause of transplant failure. Lifelong immunosuppression decreases the incidence of graft rejection; however, nonspecific immunosuppression results in increased susceptibly to infection and cancer. Regulatory T cells (T(regs)), which suppress the activation of the immune system and induce tolerance, are currently under evaluation for use in clinical transplantation. Ex vivo expanded polyclonal T(regs) that are introduced into transplant recipients alter the balance of T effector cells to T(regs); however, experimental data suggest that alloantigen-specific T(regs) would be more effective at preventing graft rejection. We have developed a method to enrich alloantigen-specific human T(regs) based on the coexpression of activation markers, CD69 and CD71. These T(regs) could be readily expanded in vitro and demonstrated potent antigen-specific suppression. In a humanized mouse model of alloimmune-mediated injury of human skin grafts, alloantigen-specific T(regs) resulted in a significant reduction in clinically relevant indicators of dermal tissue injury when compared with polyclonal T(regs), restoring a histology comparable to healthy skin. This method of human allospecific T(reg) selection should be scalable to the clinic. The improved in vivo efficacy of alloantigen-specific T(regs) over polyclonal T(regs) shown here suggests that generating "customized" T(regs) with defined anti-donor allospecificities may improve current practice in clinical immunotherapy.
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Affiliation(s)
- Pervinder Sagoo
- MRC Centre for Transplantation, King's College London, SE1 9RT London, UK
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Yu Y, Miller J, Leventhal JR, Tambur AR, Chandrasekaran D, Levitsky J, Luo X, Mathew JM. Requirement of cognate CD4+ T-cell recognition for the regulation of allospecific CTL by human CD4+ CD127- CD25+ FOXP3+ cells generated in MLR. PLoS One 2011; 6:e22450. [PMID: 21799858 PMCID: PMC3142165 DOI: 10.1371/journal.pone.0022450] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 06/22/2011] [Indexed: 11/27/2022] Open
Abstract
Although immunoregulation of alloreactive human CTLs has been described, the direct influence of CD4+ Tregs on CD8+ cytotoxicity and the interactive mechanisms have not been well clarified. Therefore, human CD4+CD127−CD25+FOXP3+ Tregs were generated in MLR, immunoselected and their allospecific regulatory functions and associated mechanisms were then tested using modified 51Chromium release assays (Micro-CML), MLRs and CFSE-based multi-fluorochrome flow cytometry proliferation assays. It was observed that increased numbers of CD4+CD127−CD25+FOXP3+ cells were generated after a 7 day MLR. After immunoselection for CD4+CD127−CD25+ cells, they were designated as MLR-Tregs. When added as third component modulators, MLR-Tregs inhibited the alloreactive proliferation of autologous PBMC in a concentration dependent manner. The inhibition was quasi-antigen specific, in that the inhibition was non-specific at higher MLR-Treg modulator doses, but non-specificity disappeared with lower numbers at which specific inhibition was still significant. When tested in micro-CML assays CTL inhibition occurred with PBMC and purified CD8+ responders. However, antigen specificity of CTL inhibition was observed only with unpurified PBMC responders and not with purified CD8+ responders or even with CD8+ responders plus Non-T “APC”. However, allospecificity of CTL regulation was restored when autologous purified CD4+ T cells were added to the CD8+ responders. Proliferation of CD8+ cells was suppressed by MLR-Tregs in the presence or absence of IL-2. Inhibition by MLR-Tregs was mediated through down-regulation of intracellular perforin, granzyme B and membrane-bound CD25 molecules on the responding CD8+ cells. Therefore, it was concluded that human CD4+CD127−CD25+FOXP3+ MLR-Tregs down-regulate alloreactive cytotoxic responses. Regulatory allospecificity, however, requires the presence of cognate responding CD4+ T cells. CD8+ CTL regulatory mechanisms include impaired proliferation, reduced expression of cytolytic molecules and CD25+ activation epitopes.
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Affiliation(s)
- Yuming Yu
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Department of Organ Transplantation, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Joshua Miller
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Jesse Brown VA Medical Center, Chicago, Illinois, United States of America
| | - Joseph R. Leventhal
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Anat R. Tambur
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Dhivya Chandrasekaran
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Josh Levitsky
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Division of Hepatology, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - Xunrong Luo
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Division of Nephrology and Hypertension, Department of Medicine, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
| | - James M. Mathew
- Department of Surgery, Comprehensive Transplant Center, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- Jesse Brown VA Medical Center, Chicago, Illinois, United States of America
- Department of Microbiology-Immunology, Northwestern University Feinberg School of Medicine, Chicago, Illinois, United States of America
- * E-mail:
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Zhao Y, Shan Z, Li Q, Zhou Y, Zeng X, Fan Q, Liao C, Zhu Y, Zhao Y, Lu X, Liu J. Effect of CD4+ Memory T Cells on Rejection Response of Ectopic Heart Transplantation in Mice. Transplant Proc 2011; 43:1989-93. [DOI: 10.1016/j.transproceed.2010.12.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 11/05/2010] [Accepted: 12/13/2010] [Indexed: 11/29/2022]
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Feng G, Nadig SN, Bäckdahl L, Beck S, Francis RS, Schiopu A, Whatcott A, Wood KJ, Bushell A. Functional regulatory T cells produced by inhibiting cyclic nucleotide phosphodiesterase type 3 prevent allograft rejection. Sci Transl Med 2011; 3:83ra40. [PMID: 21593400 PMCID: PMC3321352 DOI: 10.1126/scitranslmed.3002099] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Regulatory T cells (T(regs)) manipulated ex vivo have potential as cellular therapeutics in autoimmunity and transplantation. Although it is possible to expand naturally occurring T(regs), an attractive alternative possibility, particularly suited to solid organ and bone marrow transplantation, is the stimulation of total T cell populations with defined allogeneic antigen-presenting cells (APCs) under conditions that lead to the generation or expansion of donor-reactive, adaptive T(regs). Here we demonstrate that stimulation of mouse CD4(+) T cells by immature allogeneic dendritic cells combined with pharmacological inhibition of phosphodiesterase 3 (PDE) resulted in a functional enrichment of Foxp3(+) T cells. Without further manipulation or selection, the resultant population delayed skin allograft rejection mediated by polyclonal CD4(+) effectors or donor-reactive CD8(+) T cell receptor transgenic T cells and inhibited both effector cell proliferation and T cell priming for interferon-γ production. Notably, PDE inhibition also enhanced the enrichment of human Foxp3(+) CD4(+) T cells driven by allogeneic APCs. These cells inhibited T cell proliferation in a standard in vitro mixed lymphocyte assay and, moreover, attenuated the development of vasculopathy mediated by autologous peripheral blood mononuclear cells in a functionally relevant humanized mouse transplant model. These data establish a method for the ex vivo generation of graft-reactive, functional mouse and human T(regs) that uses a clinically approved agent, making pharmacological PDE inhibition a potential strategy for T(reg)-based therapies.
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Affiliation(s)
- Gang Feng
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Satish N. Nadig
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Liselotte Bäckdahl
- Division of Medical Inflammation Research, Department of Medical Biochemistry and Biophysics (MBB), Karolinska Institute, Scheeles väg 2, B2 Plan 4, SE-171 77 Stockholm, Sweden
| | - Stephan Beck
- Medical Genomics Group, UCL Cancer Institute, University College London, Paul O’Gorman Building 72 Huntley Street, London WC1E 6BT, UK
| | - Ross S. Francis
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Alexandru Schiopu
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Andrew Whatcott
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Kathryn J. Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
| | - Andrew Bushell
- Transplantation Research Immunology Group, Nuffield Department of Surgery, University of Oxford’ John Radcliffe Hospital, Oxford OX3 9DU, UK
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Wood KJ, Bushell A, Jones ND. Immunologic unresponsiveness to alloantigen in vivo: a role for regulatory T cells. Immunol Rev 2011; 241:119-32. [PMID: 21488894 DOI: 10.1111/j.1600-065x.2011.01013.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Exposure to alloantigen in vivo or in vitro induces alloantigen reactive regulatory T cells that can control transplant rejection. The mechanisms that underpin the activity of alloantigen reactive regulatory T cells in vivo are common with those of regulatory T cells that prevent autoimmunity. The identification and characterization of regulatory T cells that control rejection and contribute to the induction of immunologic unresponsiveness to alloantigens in vivo has opened up exciting opportunities for new therapies in transplantation. Findings from laboratory studies are informing the design of clinical protocols using regulatory T cells as a cellular therapy.
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Affiliation(s)
- Kathryn J Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
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Francis RS, Feng G, Tha-In T, Lyons IS, Wood KJ, Bushell A. Induction of transplantation tolerance converts potential effector T cells into graft-protective regulatory T cells. Eur J Immunol 2011; 41:726-38. [PMID: 21243638 PMCID: PMC3175037 DOI: 10.1002/eji.201040509] [Citation(s) in RCA: 72] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 09/28/2010] [Accepted: 11/29/2010] [Indexed: 12/14/2022]
Abstract
Naturally occurring FOXP3(+) CD4(+) Treg have a crucial role in self-tolerance. The ability to generate similar populations against alloantigens offers the possibility of preventing transplant rejection without indefinite global immunosuppression. Exposure of mice to donor alloantigens combined with anti-CD4 antibody induces operational tolerance to cardiac allografts, and generates Treg that prevent skin and islet allograft rejection in adoptive transfer models. If protocols that generate Treg in vivo are to be developed in the clinical setting it will be important to know the origin of the Treg population and the mechanisms responsible for their generation. In this study, we demonstrate that graft-protective Treg arise in vivo both from naturally occurring FOXP3(+) CD4(+) Treg and from non-regulatory FOXP3(-) CD4(+) cells. Importantly, tolerance induction also inhibits CD4(+) effector cell priming and T cells from tolerant mice have impaired effector function in vitro. Thus, adaptive tolerance induction shapes the immune response to alloantigen by converting potential effector cells into graft-protective Treg and by expanding alloreactive naturally occurring Treg. In relation to clinical tolerance induction, the data indicate that while the generation of alloreactive Treg may be critical for long-term allograft survival without chronic immunosuppression, successful protocols will also require strategies that target potential effector cells.
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Affiliation(s)
- Ross S Francis
- Transplant Research Immunology Group, Nuffield Department of Surgery, University of Oxford John Radcliffe Hospital, Oxford, UK
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Peters JH, Koenen HJPM, Hilbrands LB, Joosten I. Immunotherapy with regulatory T cells in transplantation. Immunotherapy 2011; 1:855-71. [PMID: 20636028 DOI: 10.2217/imt.09.45] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Regulatory T cell (Treg)-based immunotherapy is of great interest to induce tolerance in clinical transplantation settings. In fact, the first clinical trials of Treg infusion after stem cell transplantation have recently begun. However, many important issues regarding human Treg immunotherapy are still to be resolved. In this review, we provide a short update on Tregs and elaborate on various strategies for Treg-based immunotherapy. First, infusion of ex vivo-selected naturally occurring Tregs is addressed, with emphasis on Treg isolation, expansion, antigen specificity, homing and stability. Next, the potential of ex vivo-induced Treg transfusion strategies is discussed. Finally, therapies aimed at in vivo increase of Treg numbers or function are addressed. In addition, we summarize the current knowledge on effects of immunosuppressive drugs on Tregs. In the following years, we expect exciting new data regarding the clinical application of Treg immunotherapy in transplantation to be released.
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Affiliation(s)
- Jorieke H Peters
- Department of Blood Transfusion & Transplantation Immunology, Radboud University Nijmegen Medical Centre, PO Box 9101, 6500 HB Nijmegen, The Netherlands
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Intestinal Tolerance Requires Gut Homing and Expansion of FoxP3+ Regulatory T Cells in the Lamina Propria. Immunity 2011; 34:237-46. [DOI: 10.1016/j.immuni.2011.01.016] [Citation(s) in RCA: 649] [Impact Index Per Article: 49.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2010] [Revised: 08/10/2010] [Accepted: 12/08/2010] [Indexed: 12/17/2022]
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Ex vivo-expanded human regulatory T cells prevent the rejection of skin allografts in a humanized mouse model. Transplantation 2011; 90:1321-7. [PMID: 21048528 DOI: 10.1097/tp.0b013e3181ff8772] [Citation(s) in RCA: 161] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
BACKGROUND Composite tissue transplantation effectively reconstructs the most complex defects, but its use is limited because of harmful immunosuppression and the high susceptibility of skin to rejection. Development of tolerance is an ideal solution, and protocols using regulatory T cells (Tregs) to achieve this have been promising in experimental animal models. The aim of this study was to investigate the ability of human Tregs to regulate immune responses to a human skin allograft in vivo. METHODS We isolated and expanded naturally occurring CD127loCD25+CD4+ human Tregs from peripheral blood mononuclear cells (PBMCs) and examined their phenotype and suppressive activity in vitro. Using a clinically relevant chimeric humanized mouse system, we transplanted mice with human skin grafts followed by allogeneic populations of PBMCs with or without Tregs derived from the same PBMC donor. RESULTS Ex vivo-expanded Tregs maintain the appropriate Treg markers and retain suppressive activity against allostimulated and polyclonally stimulated autologous PBMCs in vitro. Mice receiving allogeneic PBMCs alone consistently reject human skin grafts, whereas those also receiving Tregs display stable long-term human skin transplant survival along with a reduction in the CD8+ human cellular graft infiltrate. CONCLUSIONS We show for the first time the unique ability of human Tregs to prevent the rejection of a skin allograft in vivo, highlighting the therapeutic potential of these cells clinically.
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Jones ND, Brook MO, Carvalho-Gaspar M, Luo S, Wood KJ. Regulatory T cells can prevent memory CD8+ T-cell-mediated rejection following polymorphonuclear cell depletion. Eur J Immunol 2010; 40:3107-16. [PMID: 20865790 PMCID: PMC3021718 DOI: 10.1002/eji.201040671] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/12/2010] [Accepted: 08/17/2010] [Indexed: 01/01/2023]
Abstract
Accumulating evidence suggests that alloreactive memory T cells (Tm) may form a barrier to tolerance induction in large animals and humans due in part to a resistance to suppression by Treg. However, why Tm are resistant to regulation and how the Tm response to an allograft differs from that of naïve T cells, which are amenable to suppression by Treg, remains unknown. Here, we show that accelerated graft rejection mediated by CD8+ Tm was due to the enhanced recruitment of PMN to allografts in a mouse skin allograft model. Importantly, depletion of PMN slowed the kinetics of (but did not prevent) rejection mediated by Tm and created a window of opportunity that allowed subsequent suppression of rejection by Treg. Taken together, we conclude that CD8+ Tm are not intrinsically resistant to suppression by Treg but may rapidly inflict substantial graft damage before the establishment of regulatory mechanisms. These data suggest that if Tm responses can be attenuated transiently following transplantation, Treg may be able to maintain tolerance through the suppression of both memory and naïve alloreactive T-cell responses in the long term.
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Affiliation(s)
- Nick D Jones
- Transplantation Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, John Radcliffe Hospital, Oxford, UK.
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Wieckiewicz J, Goto R, Wood KJ. T regulatory cells and the control of alloimmunity: from characterisation to clinical application. Curr Opin Immunol 2010; 22:662-8. [PMID: 20869224 PMCID: PMC3025322 DOI: 10.1016/j.coi.2010.08.011] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Revised: 08/19/2010] [Accepted: 08/24/2010] [Indexed: 12/26/2022]
Abstract
T regulatory cells (Treg) play an important role in the induction and maintenance of immunological tolerance. Recent findings in experimental transplant models combined with the development of functional reporter mice have opened new avenues to study Treg biology and their therapeutic potential. In particular, recent advances in understanding Treg function and lineage stability revealed unexpected plasticity of this lineage. Nevertheless, pre-clinical and pilot clinical trials using Treg cells as cellular therapies have been initiated suggesting the safety and feasibility of such treatment.
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Affiliation(s)
- Joanna Wieckiewicz
- Transplant Research Immunology Group, Nuffield Department of Surgical Sciences, University of Oxford, Oxford, UK
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Endogenous dendritic cells mediate the effects of intravenously injected therapeutic immunosuppressive dendritic cells in transplantation. Blood 2010; 116:2694-705. [PMID: 20576812 DOI: 10.1182/blood-2009-10-251058] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
The prevailing idea regarding the mechanism(s) by which therapeutic immunosuppressive dendritic cells (DCs) restrain alloimmunity is based on the concept that they interact directly with antidonor T cells, inducing anergy, deletion, and/or regulation. However, this idea has not been tested in vivo. Using prototypic in vitro-generated maturation-resistant (MR) DCs, we demonstrate that once MR-DCs carrying donor antigen (Ag) are administered intravenously, they decrease the direct and indirect pathway T-cell responses and prolong heart allograft survival but fail to directly regulate T cells in vivo. Rather, injected MR-DCs are short-lived and reprocessed by recipient DCs for presentation to indirect pathway CD4(+) T cells, resulting in abortive activation and deletion without detrimental effect on the number of indirect CD4(+) FoxP3(+) T cells, thus increasing the regulatory to effector T cell relative percentage. The effect on the antidonor response was independent of the method used to generate therapeutic DCs or their viability; and in accordance with the idea that recipient Ag-presenting cells mediate the effects of therapeutic DCs in transplantation, prolongation of allograft survival was achieved using donor apoptotic MR-DCs or those lacking surface major histocompatibility complex molecules. We therefore conclude that therapeutic DCs function as Ag-transporting cells rather than Ag-presenting cells to prolong allograft survival.
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Guilbride DL, Gawlinski P, Guilbride PDL. Why functional pre-erythrocytic and bloodstage malaria vaccines fail: a meta-analysis of fully protective immunizations and novel immunological model. PLoS One 2010; 5:e10685. [PMID: 20502667 PMCID: PMC2873430 DOI: 10.1371/journal.pone.0010685] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2009] [Accepted: 04/16/2010] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND Clinically protective malaria vaccines consistently fail to protect adults and children in endemic settings, and at best only partially protect infants. METHODOLOGY/PRINCIPAL FINDINGS We identify and evaluate 1916 immunization studies between 1965-February 2010, and exclude partially or nonprotective results to find 177 completely protective immunization experiments. Detailed reexamination reveals an unexpectedly mundane basis for selective vaccine failure: live malaria parasites in the skin inhibit vaccine function. We next show published molecular and cellular data support a testable, novel model where parasite-host interactions in the skin induce malaria-specific regulatory T cells, and subvert early antigen-specific immunity to parasite-specific immunotolerance. This ensures infection and tolerance to reinfection. Exposure to Plasmodium-infected mosquito bites therefore systematically triggers immunosuppression of endemic vaccine-elicited responses. The extensive vaccine trial data solidly substantiate this model experimentally. CONCLUSIONS/SIGNIFICANCE We conclude skinstage-initiated immunosuppression, unassociated with bloodstage parasites, systematically blocks vaccine function in the field. Our model exposes novel molecular and procedural strategies to significantly and quickly increase protective efficacy in both pipeline and currently ineffective malaria vaccines, and forces fundamental reassessment of central precepts determining vaccine development. This has major implications for accelerated local eliminations of malaria, and significantly increases potential for eradication.
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Lan T, Chen J, Xia J, Wang Y, Xie B, Wang F, Qi Z. Inhibition of Alloantigen-Primed Memory CD4+ and CD8+ T Cells by Hematopoietic Chimerism in Mice. Scand J Immunol 2010; 72:86-93. [DOI: 10.1111/j.1365-3083.2010.02412.x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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Boks MA, Zwaginga JJ, Van Ham SM, Ten Brinke A. An Optimized CFSE-based T-cell Suppression Assay to Evaluate the Suppressive Capacity of Regulatory T-Cells Induced by Human Tolerogenic Dendritic Cells. Scand J Immunol 2010; 72:158-68. [DOI: 10.1111/j.1365-3083.2010.02414.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Issa F, Schiopu A, Wood KJ. Role of T cells in graft rejection and transplantation tolerance. Expert Rev Clin Immunol 2010; 6:155-69. [PMID: 20383898 DOI: 10.1586/eci.09.64] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Transplantation is the most effective treatment for end-stage organ failure, but organ survival is limited by immune rejection and the side effects of immunosuppressive regimens. T cells are central to the process of transplant rejection through allorecognition of foreign antigens leading to their activation, and the orchestration of an effector response that results in organ damage. Long-term transplant acceptance in the absence of immunosuppressive therapy remains the ultimate goal in the field of transplantation and many studies are exploring potential therapies. One promising cellular therapy is the use of regulatory T cells to induce a state of donor-specific tolerance to the transplant. This article first discusses the role of T cells in transplant rejection, with a focus on the mechanisms of allorecognition and the alloresponse. This is followed by a detailed review of the current progress in the field of regulatory T-cell therapy in transplantation and the translation of this therapy to the clinical setting.
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Affiliation(s)
- Fadi Issa
- Nuffield Department of Surgery, University of Oxford, John Radcliffe Hospital, Oxford, OX3 9DU, UK.
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46
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Regulatory T cells in kidney allograft infiltrates correlate with initial inflammation and graft function. Transplantation 2010; 89:194-9. [PMID: 20098282 DOI: 10.1097/tp.0b013e3181c3ca11] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
BACKGROUND The relevance of borderline change (BL) and subclinical cellular rejection (SCR) observed in renal transplantation remains to be determined. Several studies have shown in BL and SCR the presence of a Th1 immune response, qualitatively similar to but quantitatively reduced in comparison with infiltrates typical of acute cellular rejection (ACR). METHODS To elucidate the role of regulatory T cells (Tregs) in the local control of the allogenic response, we studied their presence by immunohistochemistry in 24 biopsies with graft dysfunction (12 ACR and 12 BL) and in 16 protocol biopsies at 1 year (eight SCR and eight subclinical BL). RESULTS The proportion of Tregs in CD4 T infiltrates was higher in BL and SCR when compared with ACR. Moreover, their presence was correlated with the intensity of interstitial inflammation (r=-0.35, P=0.027, n=40) and with graft function at the time of the biopsy (r=-0.37, P=0.018, n=40). CONCLUSION These data suggest Treg recruitment at the acute phase of the allogenic response, where they could act to diminish the interstitial inflammation and its associated lesions.
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Alpha-1,2-mannosidase and hence N-glycosylation are required for regulatory T cell migration and allograft tolerance in mice. PLoS One 2010; 5:e8894. [PMID: 20126660 PMCID: PMC2811199 DOI: 10.1371/journal.pone.0008894] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2009] [Accepted: 12/11/2009] [Indexed: 11/19/2022] Open
Abstract
Background Specific immunological unresponsiveness to alloantigens can be induced in vivo by treating mice with a donor alloantigen in combination with a non-depleting anti-CD4 antibody. This tolerance induction protocol enriches for alloantigen reactive regulatory T cells (Treg). We previously demonstrated that alpha-1,2-mannosidase, an enzyme involved in the synthesis and processing of N-linked glycoproteins, is highly expressed in tolerant mice, in both graft infiltrating leukocytes and peripheral blood lymphocytes. Principal Findings In this study we have identified that alpha-1,2-mannosidase expression increases in CD25+CD4+ Treg when they encounter alloantigen in vivo. When alpha-1,2-mannosidase enzyme activity was blocked, Treg retained their capacity to suppress T cell proliferation in vitro but were unable to bind to physiologically relevant ligands in vitro. Further in vivo analysis demonstrated that blocking alpha-1,2-mannosidase in Treg resulted in the migration of significantly lower numbers to the peripheral lymph nodes in skin grafted mice following adoptive transfer, where they were less able to inhibit the proliferation of naïve T cells responding to donor alloantigen and hence unable prevent allograft rejection in vivo. Significance Taken together, our results suggest that activation of alloantigen reactive Treg results in increased alpha-1,2-mannosidase expression and altered N-glycosylation of cell surface proteins. In our experimental system, altered N-glycosylation is not essential for intrinsic Treg suppressive capacity, but is essential in vivo as it facilitates Treg migration to sites where they can regulate immune priming. Migration of Treg is central to their role in regulating in vivo immune responses and may require specific changes in N-glycosylation upon antigen encounter.
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Wei B, Baker S, Wieckiewicz J, Wood KJ. IFN-gamma triggered STAT1-PKB/AKT signalling pathway influences the function of alloantigen reactive regulatory T cells. Am J Transplant 2010; 10:69-80. [PMID: 19889125 PMCID: PMC3158990 DOI: 10.1111/j.1600-6143.2009.02858.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 08/08/2009] [Accepted: 08/26/2009] [Indexed: 01/25/2023]
Abstract
CD4+CD25+Foxp3+ regulatory T cells (Tregs) play a key role in the induction and maintenance of peripheral tolerance. Rapid and transient production of IFN-gamma by Tregs from mice tolerized to alloantigen in vivo has been shown to be critical for their regulatory function. This IFN-gamma has the potential to affect the function of cells present in the same local microenvironment as the Tregs, including the Tregs themselves. Here we investigated the mechanism by which IFN-gamma produced by Tregs triggered signaling pathways in alloantigen reactive Tregs themselves thereby influencing their function in vivo. We show that IFN-gamma production and STAT1 activation was increased, while STAT1-dependent PKB/AKT activation was downregulated in alloantigen reactive Tregs. Further, the activation of STAT1 was blocked in IFN-gamma receptor deficient as well as IFN-gamma-deficient Tregs, suggesting that IFN-gamma produced by the alloantigen reactive Tregs might act in an autocrine manner to induce STAT1 activation. Importantly, STAT1-deficient Tregs failed to control allograft rejection in vivo. Overall, these findings suggest that the IFN-gamma-induced STAT1-PKB/AKT signaling pathway plays a key role in upregulating the ability of alloantigen reactive Tregs to control graft rejection in vivo.
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Affiliation(s)
- B Wei
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of OxfordOxford OX3 9DU, UK
- Laboratory of Molecular Cell Biology, Institute of Biochemistry and Cell Biology, Chinese Academy of SciencesShanghai 200031, China (current address)
| | - S Baker
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of OxfordOxford OX3 9DU, UK
| | - J Wieckiewicz
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of OxfordOxford OX3 9DU, UK
| | - K J Wood
- Transplantation Research Immunology Group, Nuffield Department of Surgery, John Radcliffe Hospital, University of OxfordOxford OX3 9DU, UK
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Abstract
PURPOSE OF REVIEW Donor reactive regulatory T cells (Treg) play an important role in tolerance induction and maintenance in experimental transplant models. In this review we focus on the formation of the donor reactive Treg pool and explore the potential of these cells for therapeutic application in clinical transplantation. RECENT FINDINGS Donor reactive Treg can arise by both conversion of alloreactive nonregulatory cells and expansion of naturally occurring Treg (nTreg) cross-reactive with donor alloantigen but the quantitative contribution of each of these pathways is at present unclear. However, the fact that donor reactive Treg can be driven both in vivo and ex vivo by alloantigen challenge of nonregulatory precursors is encouraging as it demonstrates that the functional potential of these cells for use in clinical transplantation will not be limited by fortuitous cross-reactivity between nTreg and donor alloantigens. Treg can be generated in vivo by transplantation or alloantigen challenge in combination with Treg-permissive immunosuppression, or ex vivo by phenotypic selection or by polyclonal or antigen-specific stimulation. A number of ex-vivo protocols exist for the enrichment of Treg in the laboratory and in many cases these cells have demonstrable function both in vitro and in relevant graft-versus-host disease (GVHD) or organ transplant models. The challenge now is to understand the clinical opportunities and limitations that these populations present. SUMMARY Combined with appropriate immunosuppression, Treg generated/expanded in vivo or ex vivo may hold the final key to operational tolerance in clinical setting.
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Abstract
Clinical and experimental evidences suggest that alloreactive memory T cells may be part of the normal T-cell repertoire and that such cells are detrimental to the survival of foreign organ allografts induced by the administration of conventional immunosuppression or experimental tolerance-inducing therapies. The potential mechanisms by which alloreactive memory T cell may form a barrier to the induction of tolerance will be discussed.
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Affiliation(s)
- Nick D Jones
- Nuffield Department of Surgery, Transplantation Research Immunology Group, University of Oxford, John Radcliffe Hospital, Oxford, United Kingdom
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