126
|
Li XC, Bromberg JS, Bromberg JS. Literature watch: Implications for transplantation. Mast cells: inflammatory, immunoregulatory or something in between? Am J Transplant 2012; 12:2265. [PMID: 22925181 DOI: 10.1111/j.1600-6143.2012.04256.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
127
|
|
128
|
Maltzman JS, Bromberg JS. Leukocyte: tempus fugit vel carpe diem. Am J Transplant 2012; 12:1665. [PMID: 22741751 DOI: 10.1111/j.1600-6143.2012.04187.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
129
|
Ford ML, Bromberg JS. Memory T cells: new insights into the molecular basis of sensitivity and heterogeneity. Am J Transplant 2012; 12:1361. [PMID: 22642469 DOI: 10.1111/j.1600-6143.2012.04151.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
130
|
Bromberg JS. Transmissible fatty liver disease. Am J Transplant 2012; 12:1071. [PMID: 22537259 DOI: 10.1111/j.1600-6143.2012.04095.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
131
|
Yin N, Xu J, Ginhoux F, Randolph GJ, Merad M, Ding Y, Bromberg JS. Functional specialization of islet dendritic cell subsets. THE JOURNAL OF IMMUNOLOGY 2012; 188:4921-30. [PMID: 22508930 DOI: 10.4049/jimmunol.1103725] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Dendritic cells (DC) play important roles in both tolerance and immunity to β cells in type 1 diabetes. How and why DC can have diverse and opposing functions in islets remains elusive. To answer these questions, islet DC subsets and their specialized functions were characterized. Under both homeostatic and inflammatory conditions, there were two main tissue-resident DC subsets in islets, defined as CD11b(lo/-)CD103(+)CX3CR1(-) (CD103(+) DC), the majority of which were derived from fms-like tyrosine kinase 3-dependent pre-DC, and CD11b(+)CD103(-)CX3CR1(+) (CD11b(+) DC), the majority of which were derived from monocytes. CD103(+) DC were the major migratory DC and cross-presented islet-derived Ag in the pancreatic draining lymph node, although this DC subset displayed limited phagocytic activity. CD11b(+) DC were numerically the predominant subset (60-80%) but poorly migrated to the draining lymph node. Although CD11b(+) DC had greater phagocytic activity, they poorly presented Ag to T cells. CD11b(+) DC increased in numbers and percentage during T cell-mediated insulitis, suggesting that this subset might be involved in the pathogenesis of diabetes. These data elucidate the phenotype and function of homeostatic and inflammatory islet DC, suggesting differential roles in islet immunity.
Collapse
|
132
|
Alessandrini A, Bromberg JS. Literature watch: implications for transplantation. AHR and tryptophan catabolism: putting the effector T-cell response to sleep. Am J Transplant 2012; 12:801. [PMID: 22458381 DOI: 10.1111/j.1600-6143.2012.04058.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
133
|
|
134
|
Ding Y, Xu J, Bromberg JS. Regulatory T cell migration during an immune response. Trends Immunol 2012; 33:174-80. [PMID: 22305714 DOI: 10.1016/j.it.2012.01.002] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2011] [Revised: 12/19/2011] [Accepted: 01/04/2012] [Indexed: 02/01/2023]
Abstract
CD4(+)CD25(+)Foxp3(+) regulatory T (Treg) cells migrate into both inflammatory sites and draining lymph nodes (LNs) during an immune response, and have unique and overlaping functions in each location. Current studies suggest that Treg cells in draining LNs and inflamatory sites may not simply be a division of labor, but rather Treg cells migrate in a coordinated fashion between peripheral tissues and draining LNs. Trafficking between inflammatory sites and draining LNs is not only crucial for Treg cells to act, but also for them to acquire optimal immune regulatory activities. Furthermore, recent work has revealed that T helper (Th)1, Th2 and Th17 cell master transcription factors control Treg cell function by regulating genes important for Treg cell migration and suppression, and consequently affect disease pathogenesis.
Collapse
|
135
|
Burrell BE, Ding Y, Nakayama Y, Park KS, Xu J, Yin N, Bromberg JS. Tolerance and lymphoid organ structure and function. Front Immunol 2011; 2:64. [PMID: 22566853 PMCID: PMC3342028 DOI: 10.3389/fimmu.2011.00064] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 11/07/2011] [Indexed: 12/11/2022] Open
Abstract
This issue of Frontiers in Immunologic Tolerance explores barriers to tolerance from a variety of views of cells, molecules, and processes of the immune system. Our laboratory has spent over a decade focused on the migration of the cells of the immune system, and dissecting the signals that determine how and where effector and suppressive regulatory T cells traffic from one site to another in order to reject or protect allografts. These studies have led us to a greater appreciation of the anatomic structure of the immune system, and the realization that the path taken by lymphocytes during the course of the immune response to implanted organs determines the final outcome. In particular, the structures, microanatomic domains, and the cells and molecules that lymphocytes encounter during their transit through blood, tissues, lymphatics, and secondary lymphoid organs are powerful determinants for whether tolerance is achieved. Thus, the understanding of complex cellular and molecular processes of tolerance will not come from “96-well plate immunology,” but from an integrated understanding of the temporal and spatial changes that occur during the response to the allograft. The study of the precise positioning and movement of cells in lymphoid organs has been difficult since it is hard to visualize cells within their three-dimensional setting; instead techniques have tended to be dominated by two-dimensional renderings, although advanced confocal and two-photon systems are changing this view. It is difficult to precisely modify key molecules and events in lymphoid organs, so that existing knockouts, transgenics, inhibitors, and activators have global and pleiotropic effects, rather than precise anatomically restricted influences. Lastly, there are no well-defined postal codes or tracking systems for leukocytes, so that while we can usually track cells from point A to point B, it is exponentially more difficult or even impossible to track them to point C and beyond. We believe this represents one of the fundamental barriers to understanding the immune system and devising therapeutic approaches that take into account anatomy and structure as major controlling principles of tolerance.
Collapse
|
136
|
Yin N, Zhang N, Lal G, Xu J, Yan M, Ding Y, Bromberg JS. Lymphangiogenesis is required for pancreatic islet inflammation and diabetes. PLoS One 2011; 6:e28023. [PMID: 22132197 PMCID: PMC3223214 DOI: 10.1371/journal.pone.0028023] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2011] [Accepted: 10/30/2011] [Indexed: 11/18/2022] Open
Abstract
Lymphangiogenesis is a common phenomenon observed during inflammation and engraftment of transplants, but its precise role in the immune response and underlying mechanisms of regulation remain poorly defined. Here we showed that in response to injury and autoimmunity, lymphangiogenesis occurred around islets and played a key role in the islet inflammation in mice. Vascular endothelial growth factors receptor 3 (VEGFR3) is specifically involved in lymphangiogenesis, and blockade of VEGFR3 potently inhibited lymphangiogenesis in both islets and the draining LN during multiple low-dose streptozotocin (MLDS) induced autoimmune insulitis, which resulted in less T cell infiltration, preservation of islets and prevention of the onset of diabetes. In addition to their well-known conduit function, lymphatic endothelial cells (LEC) also produced chemokines in response to inflammation. These LEC attracted two distinct CX3CR1hi and LYVE-1+ macrophage subsets to the inflamed islets and CX3CR1hi cells were influenced by LEC to differentiate into LYVE-1+ cells closely associated with lymphatic vessels. These observations indicate a linkage among lymphangiogenesis and myeloid cell inflammation during insulitis. Thus, inhibition of lymphangiogenesis holds potential for treating insulitis and autoimmune diabetes.
Collapse
|
137
|
Bromberg JS. Literature watch implications for transplantation. Am J Transplant 2011; 11:2001. [PMID: 21957935 DOI: 10.1111/j.1600-6143.2011.03792.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
138
|
Azimzadeh AM, Lees JR, Ding Y, Bromberg JS. Immunobiology of transplantation: impact on targets for large and small molecules. Clin Pharmacol Ther 2011; 90:229-42. [PMID: 21716276 DOI: 10.1038/clpt.2011.106] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Organ transplantation is the preferred method of treatment for many forms of end-stage organ failure. However, immunosuppressive drugs that are used to avoid rejection can result in numerous undesirable effects (infection, malignancy, hypertension, diabetes, and accelerated arteriosclerosis). Moreover, they are not effective at preventing chronic rejection resulting in late graft loss. This review summarizes the fundamental concepts underlying the rejection of solid-organ allografts with the aim of highlighting potential new targets for therapeutics. Future improvement will depend on new therapeutic moieties, including biologics, to target various pathways of both the innate and adaptive arms of immunity. Results from some of the most recent clinical trials in transplantation and emerging new therapies are also discussed.
Collapse
|
139
|
Hippen KL, Merkel SC, Schirm DK, Sieben CM, Sumstad D, Kadidlo DM, McKenna DH, Bromberg JS, Levine BL, Riley JL, June CH, Scheinberg P, Douek DC, Miller JS, Wagner JE, Blazar BR. Massive ex vivo expansion of human natural regulatory T cells (T(regs)) with minimal loss of in vivo functional activity. Sci Transl Med 2011; 3:83ra41. [PMID: 21593401 DOI: 10.1126/scitranslmed.3001809] [Citation(s) in RCA: 285] [Impact Index Per Article: 21.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Graft-versus-host disease (GVHD) is a frequent and severe complication after hematopoietic cell transplantation. Natural CD4(+)CD25(+) regulatory T cells (nT(regs)) have proven highly effective in preventing GVHD and autoimmunity in murine models. Yet, clinical application of nT(regs) has been severely hampered by their low frequency and unfavorable ex vivo expansion properties. Previously, we demonstrated that umbilical cord blood (UCB) nT(regs) could be purified and expanded in vitro using good manufacturing practice (GMP) reagents; however, the initial number of nT(regs) in UCB units is limited, and average yield after expansion was only 1 × 10(9) nT(regs). Therefore, we asked whether yield could be increased by using peripheral blood (PB), which contains far larger quantities of nT(regs). PB nT(regs) were purified under GMP conditions and expanded 80-fold to yield 19 × 10(9) cells using anti-CD3 antibody-loaded, cell-based artificial antigen-presenting cells (aAPCs) that expressed the high-affinity Fc receptor and CD86. A single restimulation increased expansion to ~3000-fold and yield to >600 × 10(9) cells while maintaining Foxp3 expression and suppressor function. nT(reg) expansion was ~50 million-fold when flow sort-purified nT(regs) were restimulated four times with aAPCs. Indeed, cryopreserved donor nT(regs) restimulated four times significantly reduced GVHD lethality induced by the infusion of human T cells into immune-deficient mice. The capability to efficiently produce donor cell banks of functional nT(regs) could transform the treatment of GVHD and autoimmunity by providing an off-the-shelf, cost-effective, and proven cellular therapy.
Collapse
|
140
|
Drachenberg CB, Torrealba JR, Nankivell BJ, Rangel EB, Bajema IM, Kim DU, Arend L, Bracamonte ER, Bromberg JS, Bruijn JA, Cantarovich D, Chapman JR, Farris AB, Gaber L, Goldberg JC, Haririan A, Honsová E, Iskandar SS, Klassen DK, Kraus E, Lower F, Odorico J, Olson JL, Mittalhenkle A, Munivenkatappa R, Paraskevas S, Papadimitriou JC, Randhawa P, Reinholt FP, Renaudin K, Revelo P, Ruiz P, Samaniego MD, Shapiro R, Stratta RJ, Sutherland DER, Troxell ML, Voska L, Seshan SV, Racusen LC, Bartlett ST. Guidelines for the diagnosis of antibody-mediated rejection in pancreas allografts-updated Banff grading schema. Am J Transplant 2011; 11:1792-802. [PMID: 21812920 DOI: 10.1111/j.1600-6143.2011.03670.x] [Citation(s) in RCA: 105] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The first Banff proposal for the diagnosis of pancreas rejection (Am J Transplant 2008; 8: 237) dealt primarily with the diagnosis of acute T-cell-mediated rejection (ACMR), while only tentatively addressing issues pertaining to antibody-mediated rejection (AMR). This document presents comprehensive guidelines for the diagnosis of AMR, first proposed at the 10th Banff Conference on Allograft Pathology and refined by a broad-based multidisciplinary panel. Pancreatic AMR is best identified by a combination of serological and immunohistopathological findings consisting of (i) identification of circulating donor-specific antibodies, and histopathological data including (ii) morphological evidence of microvascular tissue injury and (iii) C4d staining in interacinar capillaries. Acute AMR is diagnosed conclusively if these three elements are present, whereas a diagnosis of suspicious for AMR is rendered if only two elements are identified. The identification of only one diagnostic element is not sufficient for the diagnosis of AMR but should prompt heightened clinical vigilance. AMR and ACMR may coexist, and should be recognized and graded independently. This proposal is based on our current knowledge of the pathogenesis of pancreas rejection and currently available tools for diagnosis. A systematized clinicopathological approach to AMR is essential for the development and assessment of much needed therapeutic interventions.
Collapse
|
141
|
Lees JR, Azimzadeh AM, Bromberg JS. Myeloid derived suppressor cells in transplantation. Curr Opin Immunol 2011; 23:692-7. [PMID: 21802931 DOI: 10.1016/j.coi.2011.07.004] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2011] [Accepted: 07/06/2011] [Indexed: 12/19/2022]
Abstract
Myeloid derived suppressor cells (MDSC) are a heterogeneous population of hematopoietic derived cell precursors that can suppress immune responses in a variety of inflammatory settings. Here we review recent studies detailing expansion of phenotypically and functionally disparate MDSC. Findings related to MDSC accumulation, activation, and mechanisms utilized in immune suppression are presented. Further, we discuss recent reports that suggest MDSC are expanded during transplantation and that modulation of MDSC can participate in preventing graft rejection.
Collapse
|
142
|
|
143
|
Dinavahi R, George A, Tretin A, Akalin E, Ames S, Bromberg JS, Deboccardo G, Dipaola N, Lerner SM, Mehrotra A, Murphy BT, Nadasdy T, Paz-Artal E, Salomon DR, Schröppel B, Sehgal V, Sachidanandam R, Heeger PS. Antibodies reactive to non-HLA antigens in transplant glomerulopathy. J Am Soc Nephrol 2011; 22:1168-78. [PMID: 21566057 DOI: 10.1681/asn.2010111183] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Although T and B cell alloimmunity contribute to transplant injury, autoimmunity directed at kidney-expressed, non-HLA antigens may also participate. Because the specificity, prevalence, and importance of antibodies to non-HLA antigens in late allograft injury are poorly characterized, we used a protein microarray to compare antibody repertoires in pre- and post-transplant sera from several cohorts of patients with and without transplant glomerulopathy. Transplantation routinely induced changes in antibody repertoires, but we did not identify any de novo non-HLA antibodies common to patients with transplant glomerulopathy. The screening studies identified three reactivities present before transplantation that persisted after transplant and strongly associated with transplant glomerulopathy. ELISA confirmed that reactivity against peroxisomal-trans-2-enoyl-coA-reductase strongly associated with the development of transplant glomerulopathy in independent validation sets. In addition to providing insight into effects of transplantation on non-HLA antibody repertoires, these results suggest that pretransplant serum antibodies to peroxisomal-trans-2-enoyl-coA-reductase may predict prognosis in kidney transplantation.
Collapse
|
144
|
Bromberg JS. Stimulation of beta cells: trying to reap what we grow. Am J Transplant 2011; 11:877. [PMID: 21521461 DOI: 10.1111/j.1600-6143.2011.03547.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
145
|
Xu J, Yang Y, Qiu G, Lal G, Yin N, Wu Z, Bromberg JS, Ding Y. Stat4 is critical for the balance between Th17 cells and regulatory T cells in colitis. THE JOURNAL OF IMMUNOLOGY 2011; 186:6597-606. [PMID: 21525389 DOI: 10.4049/jimmunol.1004074] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Th17 play a central role in autoimmune inflammatory responses. Th1 are also necessary for autoimmune disease development. The interplay of Th1 signals and how they coordinate with Th17 during inflammatory disease pathogenesis are incompletely understood. In this study, by adding Stat4 deficiency to Stat6/T-bet double knockout, we further dissected the role of Stat4 in Th1 development and colitis induction. We showed that in the absence of the strong Th2 mediator Stat6, neither Stat4 nor T-bet is required for IFN-γ production and Th1 development. However, addition of Stat4 deficiency abolished colitis induced by Stat6/T-bet double-knockout cells, despite Th1 and Th17 responses. The failure of colitis induction by Stat4/Stat6/T-bet triple-knockout cells is largely due to elevated Foxp3(+) regulatory T cell (Treg) development. These results highlight the critical role of Stat4 Th1 signals in autoimmune responses in suppressing Foxp3(+) Treg responses and altering the balance between Th17 and Tregs to favor autoimmune disease.
Collapse
|
146
|
Bromberg JS. Markers of organ function: if you search, what will you find? Am J Transplant 2011; 11:643. [PMID: 21446965 DOI: 10.1111/j.1600-6143.2011.03521.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
147
|
Chen C, Chai J, Singh L, Kuo CY, Jin L, Feng T, Marzano S, Galeni S, Zhang N, Iacovino M, Qin L, Hara M, Stein R, Bromberg JS, Kyba M, Ku HT. Characterization of an in vitro differentiation assay for pancreatic-like cell development from murine embryonic stem cells: detailed gene expression analysis. Assay Drug Dev Technol 2011; 9:403-19. [PMID: 21395400 DOI: 10.1089/adt.2010.0314] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Embryonic stem (ES) cell technology may serve as a platform for the discovery of drugs to treat diseases such as diabetes. However, because of difficulties in establishing reliable ES cell differentiation methods and in creating cost-effective plating conditions for the high-throughput format, screening for molecules that regulate pancreatic beta cells and their immediate progenitors has been limited. A relatively simple and inexpensive differentiation protocol that allows efficient generation of insulin-expressing cells from murine ES cells was previously established in our laboratories. In this report, this system is characterized in greater detail to map developmental cell stages for future screening experiments. Our results show that sequential activation of multiple gene markers for undifferentiated ES cells, epiblast, definitive endoderm, foregut, and pancreatic lineages was found to follow the sequence of events that mimics pancreatic ontogeny. Cells that expressed enhanced green fluorescent protein, driven by pancreatic and duodenal homeobox 1 or insulin 1 promoter, correctly expressed known beta cell lineage markers. Overexpression of Sox17, an endoderm fate-determining transcription factor, at a very early stage of differentiation (days 2-3) enhanced pancreatic gene expression. Overexpression of neurogenin3, an endocrine progenitor cell marker, induced glucagon expression at stages when pancreatic and duodenal homeobox 1 message was present (days 10-16). Forced expression (between days 16 and 25) of MafA, a pancreatic maturation factor, resulted in enhanced expression of insulin genes, glucose transporter 2 and glucokinase, and glucose-responsive insulin secretion. Day 20 cells implanted in vivo resulted in pancreatic-like cells. Together, our differentiation assay recapitulates the proceedings and behaviors of pancreatic development and will be valuable for future screening of beta cell effectors.
Collapse
|
148
|
Gehrie E, Van der Touw W, Bromberg JS, Ochando JC. Plasmacytoid dendritic cells in tolerance. Methods Mol Biol 2011; 677:127-47. [PMID: 20941607 DOI: 10.1007/978-1-60761-869-0_9] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Dendritic cells (DC) are professional antigen-presenting cells (APCs) that modulate the outcome of the immune response toward immunity or tolerance. There are a large variety of DC subsets according to surface phenotype, function, and tissue distribution. Murine plasmacytoid DC (pDC) represent a distinctive DC population and are characterized by the expression of CD11c, B220, Gr-1, CD45RA, Ly49Q, BST2, and siglec-H on the cell surface. PDC act as immunogenic cell sentinels by secreting large amounts of type I interferon (IFN) in the lymph nodes in response to viral stimulation. PDC also act as tolerogenic cells when expressing the inducible tolerogenic enzyme indoleamine 2,3-dioxygenase (IDO), the inducible costimulator ligand (ICOS-L), and/or the programmed death 1 ligand (PD-L1), which mediate regulatory T-cell (Treg) development and suppression of self- and alloreactive cells. The PDC ability to induce Treg development is associated with capture and presentation of antigenic peptides associated with major histocompatibility complex (MHC) class I and II. Here, we provide the tools to study PDC development from bone marrow cultures, their antigen presentation properties, and their interactions with Treg under a tolerogenic setting of sterile inflammation.
Collapse
|
149
|
|
150
|
Lal G, Yin N, Xu J, Lin M, Bernd S, Ding Y, Marie I, Levy DE, Bromberg JS. Distinct inflammatory signals have physiologically divergent effects on epigenetic regulation of Foxp3 expression and Treg function. Am J Transplant 2011; 11:203-14. [PMID: 21219575 PMCID: PMC3079560 DOI: 10.1111/j.1600-6143.2010.03389.x] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Foxp3 expression in regulatory T cells (Treg) is required for their development and suppressive function. How different inflammatory signals affect Foxp3 chromatin structure, expression and Tregs plasticity are not completely known. In the present study, the Toll-like receptor 2 (TLR2) ligand peptidoglycan inhibited Foxp3 expression in both natural Treg (nTreg) and TGFβ-driven adaptive Treg (aTreg). Inhibition was independent of paracrine Th1, Th2 and Th17 cytokines. PGN-induced T cell-intrinsic TLR2-Myd88-dependent IFR1 expression and induced IRF1 bound to IRF1 response elements (IRF-E) in the Foxp3 promoter and intronic enhancers, and negatively regulated Foxp3 expression. Inflammatory IL-6 and TLR2 signals induced divergent chromatin changes at the Foxp3 locus and regulated Treg suppressor function, and in an islet transplant model resulted in differences in their ability to prolong graft survival. These findings are important for understanding how different inflammatory signals can affect the transplantation tolerance and immunity.
Collapse
|