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Lupsa N, Érsek B, Böröczky C, Kis D, Szarka E, Lumniczky K, Sáfrány G, Zádori ZS, Szöőr Á, Buzás EI, Pós Z. High sensitivity of host Helios +/Neuropilin-1 + Treg to pretransplant conditioning hampers development of OX40 bright/integrin-β7 + regulatory cells in acute gastrointestinal GvHD. Eur J Immunol 2024:e2350619. [PMID: 38532599 DOI: 10.1002/eji.202350619] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 03/15/2024] [Accepted: 03/18/2024] [Indexed: 03/28/2024]
Abstract
This study sought to compare the behavior of Treg subsets displaying different coexpression patterns of Neuropilin-1 (Nrp1) and Helios, under the influence of gut stress unrelated to hematopoietic stem cell transplantation, pretransplantation conditioning, and posttransplant gastrointestinal acute graft versus host disease (GI-aGvHD). Host CD4+/CD25hi/Foxp3+ Treg cells, identified by flow cytometry, were isolated from various tissues of mice affected by these stressors. Expression of CD25, CTLA-4, CD39, OX40, integrin-β7, LAG3, TGFβ/LAP, granzyme-A, -B, and interleukin-10 was compared in four Treg subsets displaying Helios or Nrp1 only, both or none. Fluorescence-activated cell sorter-sorted Treg subsets, displaying markers affected in a conditioning- and GI-aGVHD-restricted manner, were further investigated by transcriptome profiling and T-cell suppression assays. We found that conditioning by irradiation greatly diminished the relative frequency of Helios+/Nrp1+ Treg, shifting the balance toward Helios-/Nrp1- Treg in the host. Upregulation of integrin-β7 and OX40 occurred in GI-aGvHD-dependent manner in Helios+/Nrp1+ cells but not in Helios-/Nrp1- Treg. Sorted Treg subsets, confirmed to overexpress Nrp1, Helios, OX40, or integrin-β7, displayed superior immunosuppressive activity and enrichment in activation-related messenger RNA transcripts. Our data suggest that conditioning-induced shrinkage of the Nrp1+/Helios+ Treg subset may contribute to the development of GI-GvHD by impairing gut homing and decreasing the efficiency of Treg-mediated immunosuppression.
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Affiliation(s)
- Nikolett Lupsa
- Department of Genetics, Cell and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Barbara Érsek
- Department of Genetics, Cell and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Csenge Böröczky
- Department of Genetics, Cell and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Dávid Kis
- Unit of Radiation Medicine, Department of Radiobiology and Radiohygiene, National Public Health Center, Budapest, Hungary
| | - Eszter Szarka
- Unit of Radiation Medicine, Department of Radiobiology and Radiohygiene, National Public Health Center, Budapest, Hungary
| | - Katalin Lumniczky
- Unit of Radiation Medicine, Department of Radiobiology and Radiohygiene, National Public Health Center, Budapest, Hungary
| | - Géza Sáfrány
- Unit of Radiation Medicine, Department of Radiobiology and Radiohygiene, National Public Health Center, Budapest, Hungary
| | - Zoltán S Zádori
- Department of Pharmacology and Pharmacotherapy, Faculty of Medicine, Semmelweis University, Budapest, Hungary
| | - Árpád Szöőr
- Department of Biophysics and Cell Biology, Faculty of Medicine, University of Debrecen, Debrecen, Hungary
| | - Edit I Buzás
- Department of Genetics, Cell and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
- Immunproteogenomics Extracellular Vesicle Research Group of the Hungarian Academy of Sciences-Semmelweis University, Budapest, Hungary
- Extracellular Vesicle Research Group, Hungarian Center of Excellence Molecular Medicine, Budapest, Hungary
| | - Zoltán Pós
- Department of Genetics, Cell and Immunobiology, Faculty of Medicine, Semmelweis University, Budapest, Hungary
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Kumar S, Leigh ND, Cao X. The Role of Co-stimulatory/Co-inhibitory Signals in Graft-vs.-Host Disease. Front Immunol 2018; 9:3003. [PMID: 30627129 PMCID: PMC6309815 DOI: 10.3389/fimmu.2018.03003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2018] [Accepted: 12/05/2018] [Indexed: 12/31/2022] Open
Abstract
Allogeneic hematopoietic cell transplantation (allo-HCT) is an effective immunotherapeutic approach for various hematologic and immunologic ailments. Despite the beneficial impact of allo-HCT, its adverse effects cause severe health concerns. After transplantation, recognition of host cells as foreign entities by donor T cells induces graft-vs.-host disease (GVHD). Activation, proliferation and trafficking of donor T cells to target organs and tissues are critical steps in the pathogenesis of GVHD. T cell activation is a synergistic process of T cell receptor (TCR) recognition of major histocompatibility complex (MHC)-anchored antigen and co-stimulatory/co-inhibitory signaling in the presence of cytokines. Most of the currently used therapeutic regimens for GVHD are based on inhibiting the allogeneic T cell response or T-cell depletion (TCD). However, the immunosuppressive drugs and TCD hamper the therapeutic potential of allo-HCT, resulting in attenuated graft-vs.-leukemia (GVL) effect as well as increased vulnerability to infection. In view of the drawback of overbroad immunosuppression, co-stimulatory, and co-inhibitory molecules are plausible targets for selective modulation of T cell activation and function that can improve the effectiveness of allo-HCT. Therefore, this review collates existing knowledge of T cell co-stimulation and co-inhibition with current research that may have the potential to provide novel approaches to cure GVHD without sacrificing the beneficial effects of allo-HCT.
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Affiliation(s)
- Sandeep Kumar
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
| | - Nicholas D Leigh
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States
| | - Xuefang Cao
- Department of Immunology, Roswell Park Comprehensive Cancer Center, Buffalo, NY, United States.,Department of Microbiology and Immunology, Marlene and Stewart Greenebaum Comprehensive Cancer Center, University of Maryland, Baltimore, MD, United States
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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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Kean LS, Turka LA, Blazar BR. Advances in targeting co-inhibitory and co-stimulatory pathways in transplantation settings: the Yin to the Yang of cancer immunotherapy. Immunol Rev 2017; 276:192-212. [PMID: 28258702 PMCID: PMC5338458 DOI: 10.1111/imr.12523] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
In the past decade, the power of harnessing T-cell co-signaling pathways has become increasingly understood to have significant clinical importance. In cancer immunotherapy, the field has concentrated on two related modalities: First, targeting cancer antigens through highly activated chimeric antigen T cells (CAR-Ts) and second, re-animating endogenous quiescent T cells through checkpoint blockade. In each of these strategies, the therapeutic goal is to re-ignite T-cell immunity, in order to eradicate tumors. In transplantation, there is also great interest in targeting T-cell co-signaling, but with the opposite goal: in this field, we seek the Yin to cancer immunotherapy's Yang, and focus on manipulating T-cell co-signaling to induce tolerance rather than activation. In this review, we discuss the major T-cell signaling pathways that are being investigated for tolerance induction, detailing preclinical studies and the path to the clinic for many of these molecules. These include blockade of co-stimulation pathways and agonism of coinhibitory pathways, in order to achieve the delicate state of balance that is transplant tolerance: a state which guarantees lifelong transplant acceptance without ongoing immunosuppression, and with preservation of protective immune responses. In the context of the clinical translation of immune tolerance strategies, we discuss the significant challenge that is embodied by the fact that targeted pathway modulators may have opposing effects on tolerance based on their impact on effector vs regulatory T-cell biology. Achieving this delicate balance holds the key to the major challenge of transplantation: lifelong control of alloreactivity while maintaining an otherwise intact immune system.
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Affiliation(s)
- Leslie S. Kean
- Ben Towne Center for Childhood Cancer Research, Seattle Children’s Research Institute, The Fred Hutchinson Cancer Research Center and the Department of Pediatrics, University of Washington, Seattle Washington
| | - Laurence A. Turka
- Center for Transplantation Sciences, Department of Surgery, and Immune Tolerance Network, Massachusetts General Hospital and Harvard Medical School, Boston, MA
| | - Bruce R. Blazar
- Division of Blood and Marrow Transplantation, Department of Pediatrics and the Masonic Cancer Center, University of Minnesota, Minneapolis, MN
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Kang SA, Park MK, Cho MK, Park SK, Jang MS, Yang BG, Jang MH, Kim DH, Yu HS. Parasitic nematode-induced CD4+Foxp3+T cells can ameliorate allergic airway inflammation. PLoS Negl Trop Dis 2014; 8:e3410. [PMID: 25522145 PMCID: PMC4270642 DOI: 10.1371/journal.pntd.0003410] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 11/12/2014] [Indexed: 12/14/2022] Open
Abstract
Background The recruitment of CD4+CD25+Foxp3+T (Treg) cells is one of the most important mechanisms by which parasites down-regulate the immune system. Methodology/Principal Findings We compared the effects of Treg cells from Trichinella spiralis-infected mice and uninfected mice on experimental allergic airway inflammation in order to understand the functions of parasite-induced Treg cells. After four weeks of T. spiralis infection, we isolated Foxp3-GFP-expressing cells from transgenic mice using a cell sorter. We injected CD4+Foxp3+ cells from T. spiralis-infected [Inf(+)Foxp3+] or uninfected [Inf(-)Foxp3+] mice into the tail veins of C57BL/6 mice before the induction of inflammation or during inflammation. Inflammation was induced by ovalbumin (OVA)-alum sensitization and OVA challenge. The concentrations of the Th2-related cytokines IL-4, IL-5, and IL-13 in the bronchial alveolar lavage fluid and the levels of OVA-specific IgE and IgG1 in the serum were lower in mice that received intravenous application of Inf(+)Foxp3+ cells [IV(inf):+(+) group] than in control mice. Some features of allergic airway inflammation were ameliorated by the intravenous application of Inf(-)Foxp3+ cells [IV(inf):+(-) group], but the effects were less distinct than those observed in the IV(inf):+(+) group. We found that Inf(+)Foxp3+ cells migrated to inflammation sites in the lung and expressed higher levels of Treg-cell homing receptors (CCR5 and CCR9) and activation markers (Klrg1, Capg, GARP, Gzmb, OX40) than did Inf(-)Foxp3+ cells. Conclusion/Significance T. spiralis infection promotes the proliferation and functional activation of Treg cells. Parasite-induced Treg cells migrate to the inflammation site and suppress immune responses more effectively than non-parasite-induced Treg cells. The adoptive transfer of Inf(+)Foxp3+ cells is an effective method for the treatment and prevention of allergic airway diseases in mice and is a promising therapeutic approach for the treatment of allergic airway diseases. Many studies have investigated the down-regulation of the immune system by parasite infection. CD4+CD25+Foxp3+T (Treg) cells are key players in parasite-mediated immune downregulation. Our previous study suggested that Treg cells recruited by Trichinella spiralis infection were the key cells mediating the amelioration of allergic airway inflammation in mice. In the present study, we investigated the functions of parasite-induced Treg cells using mice expressing GFP-tagged Foxp3. T. spiralis infection increased the number of Treg cells. Adoptive transfer of the parasite-induced Treg cells to mice with allergic airway inflammation ameliorated allergic airway inflammation. The transferred cells were recruited to inflammation sites in the lung. Cells from parasite-infected mice expressed higher levels of Treg-cell homing receptors and activation markers than did cells from uninfected mice. This study might help explain why immune disorders (often of unknown cause) are more prevalent among people in developed countries (areas with low parasite infection) than among those in developing countries (areas with parasite epidemics). Our finding might improve current cell therapy techniques and facilitate the development of new techniques that use parasites or parasite-borne materials to treat diverse immune disorders.
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Affiliation(s)
- Shin Ae Kang
- Department of Parasitology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
- Immunoregulatory therapeutics group in Brain Busan 21 project, Yangsan, Republic of Korea
| | - Mi-Kyung Park
- Department of Parasitology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
- Immunoregulatory therapeutics group in Brain Busan 21 project, Yangsan, Republic of Korea
| | - Min Kyoung Cho
- Department of Parasitology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
| | - Sang Kyun Park
- Department of Parasitology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
- Immunoregulatory therapeutics group in Brain Busan 21 project, Yangsan, Republic of Korea
| | - Min Seong Jang
- Academy of Immunology and Microbiology (AIM), Institute for Basic Science (IBS), Pohang, Republic of Korea
| | - Bo-Gie Yang
- Academy of Immunology and Microbiology (AIM), Institute for Basic Science (IBS), Pohang, Republic of Korea
| | - Myoung Ho Jang
- Academy of Immunology and Microbiology (AIM), Institute for Basic Science (IBS), Pohang, Republic of Korea
| | - Dong-Hee Kim
- Department of Nursing, College of Nursing, Pusan National University, Yangsan, Republic of Korea
| | - Hak Sun Yu
- Department of Parasitology, School of Medicine, Pusan National University, Yangsan, Republic of Korea
- Immunoregulatory therapeutics group in Brain Busan 21 project, Yangsan, Republic of Korea
- * E-mail:
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Mays JW, Fassil H, Edwards DA, Pavletic SZ, Bassim CW. Oral chronic graft-versus-host disease: current pathogenesis, therapy, and research. Oral Dis 2012; 19:327-46. [PMID: 23107104 DOI: 10.1111/odi.12028] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 09/11/2012] [Accepted: 09/11/2012] [Indexed: 12/13/2022]
Abstract
Optimal management of complex autoimmune diseases requires a multidisciplinary medical team including dentists to care for lesions of the oral cavity. In this review, we discuss the presentation, prevalence, diagnosis, and treatment of oral manifestations in chronic graft-versus-host disease (cGVHD), which is a major late complication in patients treated by allogeneic hematopoietic stem cell transplantation. We assess current general knowledge of systemic and oral cGVHD and present general treatment recommendations based on literature review and our clinical experience. Additionally, we review areas where the understanding of oral cGVHD could be improved by further research and address tools with which to accomplish the long-term goal of providing better health and quality of life to patients with cGVHD.
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Affiliation(s)
- J W Mays
- Clinical Research Core, National Institute of Dental and Craniofacial Research, Bethesda, MD 20892-4320, USA.
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Lin SJ, Yan DC, Lee YC, Hsiao HS, Lee PT, Liang YW, Kuo ML. Umbilical cord blood immunology: relevance to stem cell transplantation. Clin Rev Allergy Immunol 2012; 42:45-57. [PMID: 22134956 DOI: 10.1007/s12016-011-8289-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Because of its easier accessibility and less severe graft-versus-host disease, umbilical cord blood (UCB) has been increasingly used as an alternative to bone marrow for hematopoietic stem cell transplantation. Naiveté of UCB lymphocytes, however, results in delayed immune reconstitution and infection-related mortality in transplant recipients. This review updates the phenotypic and functional deficiencies of various immune cell populations in UCB compared with their adult counterparts and discusses clinical implications and possible therapeutic strategies to improve the outcome of stem cell transplantation.
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Affiliation(s)
- Syh-Jae Lin
- Division of Asthma, Allergy, and Rheumatology Department of Pediatrics, Chang Gung Children's Hospital, College of Medicine, Chang Gung University, Taoyuan, Taiwan, Republic of China
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Qu Y, Zhao Y. Regulatory CD4+CD25+T-cells are Controlled by Multiple Pathways at Multiple Levels. Int Rev Immunol 2009; 26:145-60. [PMID: 17558742 DOI: 10.1080/08830180701365917] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
CD4(+)CD25(+) regulatory T-cells (Treg cells) are an important subset of T-cells that functions to negatively control immune responses to self or non-self antigens. Depletion of CD4(+)CD25(+) Treg cells leads to the occurrence of lymphoproliferative autoimmune diseases in animals and humans. Therefore, CD4(+)CD25(+) Treg cells must be tightly regulated in the physiologic situation. In this article, we try to summarize the regulating pathways of the development, survival, and function of CD4(+)CD25(+) Treg cells at multiple levels and multiple pathways, including the dendritic cells, costimulatory signals, cytokines, as well as intracellular signals.
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Affiliation(s)
- Yanyan Qu
- Transplantation Biology Research Division, State Key Laboratory of Biomembrane and Membrane Biotechnology, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
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Liu Y, Chen Y, Liu FQ, Lamb JR, Tam PKH. Combined treatment with triptolide and rapamycin prolongs graft survival in a mouse model of cardiac transplantation. Transpl Int 2008; 21:483-94. [PMID: 18266776 DOI: 10.1111/j.1432-2277.2007.00630.x] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Current immunosuppressive strategies for transplantation have failed to achieve long-term graft survival. In this study, we investigate the effects of combined treatment with triptolide (TPT) and rapamycin (Rapa) on graft survival as well as changes in pathology and immunological responses. Heterotopic heart transplantation was performed. TPT and Rapa were administered either alone or in combination. The mean survival time (MST) for the cardiac allografts in animals receiving the combination of TPT and Rapa was 93.5 +/- 6.7 days compared to treatment with TPT (MST: 23.5 +/- 5.3 days), Rapa (22 +/- 1.3 days) alone or no treatment (7.66 +/- 0.8 days). Histopathological evaluation showed that inflammatory cell infiltration was markedly reduced in grafts with combined treatment groups. Down-regulation of CCL19, CCR5, CCR7, interferon gamma and interleukin (IL)-12 in the combination treatment was accompanied by increased expression of IL-4, IL-10 and CD4(+)CD25(+)Foxp3(+) regulatory T (Tr) cells in spleen. Finally, dendritic cell (DC) maturation was impaired by treatment with TPT/Rapa. Our results demonstrate that combination therapy with TPT and Rapa markedly prolongs cardiac allograft survival. This effect is accompanied by inhibition of DCs maturation, conditioning DCs to adopt tolerogenic phenotype, and the expansion of Tr cells. These results add weight to the application of combination therapy in transplantation.
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Affiliation(s)
- Yan Liu
- Department of Surgery, University of Hong Kong Medical Centre, Queen Mary Hospital, Hong Kong, China
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