Transplantation
Abstract
Commonly available clinical parameters fail to predict early acute cellular rejection (EAR, occurring within 6 months after transplant), a major risk factor for graft loss after kidney transplantation. We performed whole-blood RNA sequencing at the time of transplant in 235 kidney transplant recipients enrolled in a prospective cohort study (Genomics of Chronic Allograft Rejection [GoCAR]) and evaluated the relationship of pretransplant transcriptomic profiles with EAR. EAR was associated with downregulation of NK and CD8+ T cell gene signatures in pretransplant blood. We identified a 23-gene set that predicted EAR in the discovery (n = 81, and AUC = 0.80) and validation (n = 74, and AUC = 0.74) sets. Exclusion of recipients with 5 or 6 HLA donor mismatches increased the AUC to 0.89. The risk score derived from the gene set was also significantly associated with acute cellular rejection after 6 months, antibody-mediated rejection and/or de novo donor-specific antibodies, and graft loss in a cohort of 154 patients, combining the validation set and additional GoCAR patients with surveillance biopsies between 6 and 24 months (n = 80) posttransplant. This 23-gene set is a potentially important new tool for determination of the recipient’s immunological risk before kidney transplantation, and facilitation of an individualized approach to immunosuppressive therapy.
Authors
Weijia Zhang, Zhengzi Yi, Chengguo Wei, Karen L. Keung, Zeguo Sun, Caixia Xi, Christopher Woytovich, Samira Farouk, Lorenzo Gallon, Madhav C. Menon, Ciara Magee, Nader Najafian, Milagros D. Samaniego, Arjang Djamali, Stephen I. Alexander, Ivy A. Rosales, Rex Neal Smith, Philip J. O’Connell, Robert Colvin, Paolo Cravedi, Barbara Murphy
Abstract
BACKGROUND In preclinical murine and early clinical studies of hematopoietic cell transplantation, engineering of donor grafts with defined ratios of CD4+CD25+FoxP3+ Tregs to conventional T cells (Tcons) results in the prevention of graft-versus-host disease and improved immune reconstitution. The use of highly purified primary graft Tregs for direct cell infusion has potential advantages over impure immunomagnetic selection or culture expansion, but has not been tested clinically. We performed a phase I study of the timed addition of CD34-selected hematopoietic stem cells and Tregs, followed by Tcons for the treatment of patients with high-risk hematological malignancies.METHODS We present interim evaluation of a single-center open phase I/II study of administration of human leukocyte-matched Tregs and CD34-selected hematopoietic cells, followed by infusion of an equal ratio of Tcons in adult patients undergoing myeloablative hematopoietic stem cell transplantation (HCT) for high-risk or active hematological malignancies. Tregs were purified by immunomagnetic selection and high-speed cell sorting.RESULTS Here we report results for the first 12 patients who received Tregs of between 91% and 96% purity. Greater than grade II GVHD was noted in 2 patients in the first cohort of 5 patients, who received cryopreserved Tregs, but neither acute nor chronic GVHD was noted in the second cohort of 7 patients, who received fresh Tregs and single-agent GVHD prophylaxis. Patients in the second cohort appeared to have normal immune reconstitution compared with patients who underwent transplantation and did not develop GVHD.CONCLUSION Our study shows that the use of highly purified fresh Tregs is clinically feasible and supports continued investigation of the strategy.TRIAL REGISTRATION ClinicalTrials.gov NCT01660607.FUNDING NIH NHBLI R01 HL114591 and K08HL119590.
Authors
Everett H. Meyer, Ginna Laport, Bryan J. Xie, Kate MacDonald, Kartoosh Heydari, Bita Sahaf, Sai-Wen Tang, Jeanette Baker, Randall Armstrong, Keri Tate, Cynthia Tadisco, Sally Arai, Laura Johnston, Robert Lowsky, Lori Muffly, Andrew R. Rezvani, Judith Shizuru, Wen-Kai Weng, Kevin Sheehan, David Miklos, Robert S. Negrin
Abstract
Despite current immunosuppressive strategies, long-term lung transplant outcomes remain poor due to rapid allogenic responses. Using a stringent mouse model of allo-airway transplantation, we identify the CCR4-ligand axis as a central node driving secondary lymphoid tissue homing and activation of the allogeneic T cells that prevent long-term allograft survival. CCR4 deficiency on transplant recipient T cells diminishes allograft injury and when combined with CTLA4-Ig leads to an unprecedented long-term lung allograft accommodation. Thus, we identify CCR4-ligand interactions as a central mechanism driving allogeneic transplant rejection and suggest it as a potential target to enhance long-term lung transplant survival.
Authors
Vyacheslav Palchevskiy, Ying Ying Xue, Rita Kern, Stephen S. Weigt, Aric L. Gregson, Sophie X. Song, Michael C. Fishbein, Cory M. Hogaboam, David M. Sayah, Joseph P. Lynch, III, Michael P. Keane, David G. Brooks, John A. Belperio
Abstract
Obliterative bronchiolitis (OB) is a poorly understood airway disease characterized by the generation of fibrotic bronchiolar occlusions. In the lung transplant setting, OB is a pathological manifestation of bronchiolitis obliterans syndrome (BOS), which is a major impediment to long-term recipient survival. Club cells play a key role in bronchiolar epithelial repair, but whether they promote lung transplant tolerance through preventing OB remains unclear. We determined if OB occurs in mouse orthotopic lung transplants following conditional transgene-targeted club cell depletion. In syngeneic lung transplants club cell depletion leads to transient epithelial injury followed by rapid club cell-mediated repair. In contrast, allogeneic lung transplants develop severe OB lesions and poorly regenerate club cells despite immunosuppression treatment. Lung allograft club cell ablation also triggers the recognition of alloantigens, and pulmonary restricted self-antigens reported associated with BOS development. However, CD8+ T cell depletion restores club cell reparative responses and prevents OB. In addition, ex-vivo analysis reveals a specific role for alloantigen-primed effector CD8+ T cells in preventing club cell proliferation and maintenance. Taken together, we demonstrate a vital role for club cells in maintaining lung transplant tolerance and propose a new model to identify the underlying mechanisms of OB.
Authors
Zhiyi Liu, Fuyi Liao, Davide Scozzi, Yuka Furuya, Kaitlyn N. Pugh, Ramsey R. Hachem, Delphine L. Chen, Marlene Cano, Jonathan M. Green, Alexander S. Krupnick, Daniel Kreisel, Anne-Karina T. Perl, Howard J. Huang, Steven L. Brody, Andrew E. Gelman
Abstract
Antibody-mediated lymphoablation is used in solid organ and stem cell transplantation and autoimmunity. Using murine anti-thymocyte globulin (mATG) in a mouse model of heart transplantation, we previously reported that the homeostatic recovery of CD8+ T cells requires help from depletion-resistant memory CD4+ T cells delivered through CD40-expressing B cells. This study investigated the mechanisms by which B cells mediate CD8+ T cell proliferation in lymphopenic hosts. While CD8+ T cell recovery required MHC class I expression in the host, the reconstitution occurred independently of MHC class I, MHC class II, or CD80/CD86 expression on B cells. mATG lymphoablation upregulated the B cell expression of several cytokine genes, including IL-15 and IL-27, in a CD4-dependent manner. Neither treatment with anti-CD122 mAb nor the use of IL-15Rα–/– recipients altered CD8+ T cell recovery after mATG treatment, indicating that IL-15 may be dispensable for T cell proliferation in our model. Instead, IL-27 neutralization or the use of IL-27Rα–/– CD8+ T cells inhibited CD8+ T cell proliferation and altered the phenotype and cytokine profile of reconstituted CD8+ T cells. Our findings uncover what we believe is a novel role of IL-27 in lymphopenia-induced CD8+ T cell proliferation and suggest that targeting B cell–derived cytokines may increase the efficacy of lymphoablation and improve transplant outcomes.
Authors
Katayoun Ayasoufi, Daniel B. Zwick, Ran Fan, Suheyla Hasgur, Michael Nicosia, Victoria Gorbacheva, Karen S. Keslar, Booki Min, Robert L. Fairchild, Anna Valujskikh
Abstract
Chimeric antigen receptor (CAR) technology can be used to engineer the antigen-specificity of regulatory T cells (Tregs) and improve their potency as an adoptive cell therapy in multiple disease models. As synthetic receptors, CARs carry the risk of immunogenicity, particularly when derived from non-human antibodies. Using an HLA-A*02:01-specific CAR (A2-CAR) encoding a single-chain Fv derived from a mouse antibody, we developed a panel of 20 humanized (h)A2-CARs. Systematic testing demonstrated variations in expression, ability to bind HLA-A*02:01, and stimulate human Treg suppression in vitro. In addition, we developed a new method to comprehensively map the alloantigen-specificity of CARs, revealing that humanization reduced HLA-A cross reactivity. In vivo bioluminescence imaging showed rapid trafficking and persistence of hA2-CAR Tregs in A2-expressing allografts, with eventual migration to draining lymph nodes. Adoptive transfer of hA2-CAR Tregs suppressed HLA-A2+ cell mediated xenogeneic graft-versus-host disease and diminished rejection of human HLA-A2+ skin allografts. These data provide a platform for systematic development and specificity testing of humanized alloantigen-specific CARs which can be used to engineer specificity and homing of therapeutic Tregs.
Authors
Nicholas A.J. Dawson, Caroline Lamarche, Romy E. Hoeppli, Peter Bergqvist, Vivian Fung, Emma McIver, Qing Huang, Jana Gillies, Madeleine Speck, Paul C. Orban, Jonathan W. Bush, Majid Mojibian, Megan K. Levings
Abstract
Lung transplantation (LTx) is the only therapeutic option for many patients with chronic lung disease. However, long-term survival after LTx is severely compromised by chronic rejection (chronic lung allograft dysfunction [CLAD]), which affects 50% of recipients after 5 years. The underlying mechanisms for CLAD are poorly understood, largely due to a lack of clinically relevant animal models, but lymphocytic bronchiolitis is an early sign of CLAD. Here, we report that lymphocytic bronchiolitis occurs early in a long-term murine orthotopic LTx model, based on a single mismatch (grafts from HLA-A2:B6–knockin donors transplanted into B6 recipients). Lymphocytic bronchiolitis is followed by formation of B cell–dependent lymphoid follicles that induce adjacent bronchial epithelial cell dysfunction in a spatiotemporal fashion. B cell deficiency using recipient μMT–/– mice prevented intrapulmonary lymphoid follicle formation and lymphocytic bronchiolitis. Importantly, selective inhibition of the follicle-organizing receptor EBI2, using genetic deletion or pharmacologic inhibition, prevented functional and histological deterioration of mismatched lung grafts. In sum, we provided what we believe to be a mouse model of chronic rejection and lymphocytic bronchiolitis after LTx and identified intrapulmonary lymphoid follicle formation as a target for pharmacological intervention of long-term allograft dysfunction after LTx.
Authors
Natalia F. Smirnova, Thomas M. Conlon, Carmela Morrone, Peter Dorfmuller, Marc Humbert, Georgios Stathopoulos, Stephan Umkehrer, Franz Pfeiffer, Ali Ö. Yildirim, Oliver Eickelberg
Abstract
Soluble STimulation-2 (ST2) is increased during graft-versus-host disease (GVHD) while regulatory T cells (Tregs) that express ST2 prevent GVHD through unknown mechanisms. Transplantation of Foxp3- T cells and Tregs sorted from different Foxp3 reporter mice indicated that ST2+Tregs isolated from GVHD mice were thymus-derived and predominantly intestine localized. ST2-/- Tregs transplantation was associated with reduced total intestinal Tregs frequency and activation. ST2-/- vs wild-type intestinal Tregs transcriptomes showed decreased Treg functional markers and reciprocally, increased Rorc expression. Rorc-/- T cells transplantation enhanced the frequency and function of intestinal ST2+Tregs and reduced GVHD through decreased gut-infiltrating soluble ST2-producing type-1 and increased IL-4+IL-10+ producing type-2 T cells. Cotransfer of ST2+Tregs sorted from Rorc-/- mice with WT CD25-depleted T cells decreased GVHD severity and mortality, increased intestinal ST2+KLRG1+ Tregs and decreased type-1 T cells after transplantation, indicating an intrinsic mechanism. Ex vivo IL-33 stimulated Tregs (TregIL-33) expressed higher amphiregulin, displayed better immunosuppression, and adoptive transfer prevented GVHD better than control Tregs or TregIL-33 cultured with IL-23/IL-17. Amphiregulin blockade by neutralizing antibody in vivo abolished the protective effect of TregIL-33. Our data show an inversely expression of ST2 and RORγt in intestinal Tregs, and TregIL-33 is a potential cellular therapy avenue for preventing GVHD.
Authors
Jinfeng Yang, Abdulraouf Ramadan, Dawn K. Reichenbach, Michael Loschi, Jilu Zhang, Brad Griesenauer, Hong Liu, Keli L. Hippen, Bruce R. Blazar, Sophie Paczesny
Abstract
BACKGROUND. Human cytomegalovirus (CMV) reactivation is a common occurrence early after transplant and is associated with heterogeneous NK cell subset expansion. These adaptive NK cell expansions are highly variable between recipients, with respect to magnitude and relative frequencies of adaptive NK cell subsets. METHODS. To gain insight into the factors that influence adaptive NK cell expansion from a CMV naive graft source, we performed a high-resolution NK cell and CD8+ T cell phenotypic analysis of 215 patients with hematological malignancies that were transplanted with 2 partially HLA matched CMV negative umbilical cord blood units. RESULTS. We found that adaptive NK cells were significantly higher in recipients who received nonmyeloablative conditioning (NMAC) relative to myeloablative conditioning (MAC), and high CMV neutralizing antibody titers correlated with the degree of adaptive NK cell expansion. The frequencies of adaptive NK cell subsets (defined by NKG2C, FcεRγ, EAT-2, and SYK expression) that reconstitute from donor hematopoietic progenitor cells largely matched the frequencies observed in the NK cell compartment of the recipient prior to conditioning, suggesting that host — as well as viral reactivation factors — may determine the phenotypic diversification after transplant. Additionally, multivariable analyses show that higher adaptive NK cell expansion associated with better disease-free survival. CONCLUSIONS. Our findings provide important insights into adaptive NK cell reconstitution after transplant and support a role for adaptive NK cells in promoting better clinical outcomes. FUNDING. The NIH and the National Marrow Donor Program.
Authors
Frank Cichocki, Emily Taras, Flavia Chiuppesi, John E. Wagner, Bruce R. Blazar, Claudio Brunstein, Xianghua Luo, Don J. Diamond, Sarah Cooley, Daniel J. Weisdorf, Jeffrey S. Miller
Abstract
CD4+ follicular helper T (Tfh) cells are specialized providers of T cell help to B cells and can function as pathogenic mediators of murine antibody-dependent chronic graft-versus-host disease (GvHD). Using a parent→F1 model of lupus-like chronic GvHD, in which Tfh cell and germinal center (GC) B cell differentiation occurs over 14 days, we demonstrate that absence of CD4+ T cell–expressed C5a receptor 1 (C5ar1) or pharmacological C5aR1 blockade abrogated generation/expansion of Tfh cells, GC B cells, and autoantibodies. In a Tfh cell–dependent model of chronic GvHD manifested by bronchiolitis obliterans syndrome (BOS), C5aR1 antagonism initiated in mice with established disease ameliorated BOS and abolished the associated differentiation of Tfh and GC B cells. Guided by RNA-sequencing data, mechanistic studies performed using murine and human T cells showed that C5aR1 signaling amplifies IL-6–dependent expression of the transcription factor c-MAF and the cytokine IL-21 via phosphorylating phosphokinase B (AKT) and activating the mammalian target of rapamycin (mTOR). In addition to linking C5aR1-initiated signaling to Tfh cell differentiation, our findings suggest that C5aR1 may be a useful therapeutic target for prevention and/or treatment of individuals with Tfh cell–dependent diseases, including those chronic GvHD patients who have anti-host reactive antibodies.
Authors
Divya A. Verghese, Nicholas Chun, Katelyn Paz, Miguel Fribourg, Trent M. Woodruff, Ryan Flynn, Yuan Hu, Huabao Xiong, Weijia Zhang, Zhengzi Yi, Jing Du, Bruce R. Blazar, Peter S. Heeger
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