scholarly journals Circulating Exosomal miR-17 Inhibits the Induction of Regulatory T Cells via Suppressing TGFBR II Expression in Rheumatoid Arthritis

2018 ◽  
Vol 50 (5) ◽  
pp. 1754-1763 ◽  
Author(s):  
Liping Wang ◽  
Chunyan Wang ◽  
Xuqiang Jia ◽  
Jing Yu

Background/Aims: A reduced prevalence of circulating regulatory T cells (Tregs)is a hallmark of inflammatory rheumatoid arthritis (RA). However, the underlying mechanisms of alterations of Tregs are unclear. Methods: The ratio of Tregs in peripheral blood of healthy controls (HCs) and patients with RA was determined by flow cytometry. MicroRNA (miRNA) expression profiles in exosomes derived from RA patients (RA-exosomes) and in those from HCs (HC-exosomes) were detected by microarray analysis, and miR-17 was measured by quantitative real-time PCR. Transforming growth factor beta receptor II (TGFBR II) expressed by T cells was measured by flow cytometry. The interaction between miR-17 and TGFBR II was evaluated by dual-luciferase reporter assay. Results: We found that RA-exosomes can selectively affect Treg differentiation in vitro. Several miRNAs are more abundant in the RA-exosomes than in HC-exosomes. Among those upregulated in patients with RA, miR-17 can suppress Treg induction by inhibiting the expression of TGFBR II. Conclusion: Our findings imply that altered miRNA expression in RA-exosomes may contribute to the pathogenesis of RA by disrupting the homeostasis of Tregs.

2020 ◽  
Vol 2020 ◽  
pp. 1-8 ◽  
Author(s):  
Mohsen Ghoryani ◽  
Zhaleh Shariati-Sarabi ◽  
Jalil Tavakkol-Afshari ◽  
Mojgan Mohammadi

Rheumatoid arthritis (RA) is an advanced autoimmune disease described by joint involvement. The special properties of mesenchymal stem cells (MSCs) introduced them as a potential therapeutic candidate for RA. In this study, a single dose of autologous MSCs isolated from bone marrow (autologous BM-MSCs, 1×106 per kg) was injected intravenously into 13 patients suffering from refractory RA who were followed up within 12 months after the intervention to evaluate immunological elements. Our results showed that the gene expression of forkhead box P3 (FOXP3) in peripheral blood mononuclear cells (PBMCs) considerably increased at month 12. We found a substantial increasing trend in the culture supernatant levels of IL-10 and transforming growth factor-beta 1 (TGF-β1) in PBMCs from the beginning of the intervention up to the end. Our data may reflect the sufficient immunoregulatory effect of autologous BM-MSCs on regulatory T cells in patients suffering from refractory RA.


2003 ◽  
Vol 198 (8) ◽  
pp. 1179-1188 ◽  
Author(s):  
Atsushi Kitani ◽  
Ivan Fuss ◽  
Kazuhiko Nakamura ◽  
Fumiyuki Kumaki ◽  
Takashi Usui ◽  
...  

Interleukin (IL)-10 and transforming growth factor (TGF)-β1 are suppressor cytokines that frequently occur together during a regulatory T cell response. Here we used a one gene doxycycline (Dox)-inducible plasmid encoding TGF-β1 to analyze this association and test its utility. In initial studies, we showed that intranasal administration of this plasmid (along with Dox) led to the appearance of TGF-β1–producing cells (in spleen and lamina propria) and the almost concomitant appearance of IL-10–producing cells. Moreover, we showed that these cells exert Dox-regulated suppression of the T helper cell (Th)1-mediated inflammation in trinitrobenzene sulfonic acid colitis. In subsequent in vitro studies using retroviral TGF-β1 expression, we established that IL-10 production by Th1 cells occurs after exposure to TGF-β1 from either an endogenous or exogenous source. In addition, using a self-inactivating retrovirus luciferase reporter construct we showed that TGF-β1 induces Smad4, which then binds to and activates the IL-10 promoter. Furthermore, intranasal TGF-β1 plasmid administration ameliorates bleomycin-induced fibrosis in wild-type but not IL-10–deficient mice, strongly suggesting that the amelioration is IL-10 dependent and that IL-10 protects mice from TGF-β1–mediated fibrosis. Taken together, these findings suggest that the induction of IL-10 by TGF-β1 is not fortuitous, but instead fulfills important requirements of TGF-β1 function after its secretion by regulatory T cells.


Blood ◽  
2008 ◽  
Vol 112 (5) ◽  
pp. 1813-1821 ◽  
Author(s):  
Jeremy B. Samon ◽  
Ameya Champhekar ◽  
Lisa M. Minter ◽  
Janice C. Telfer ◽  
Lucio Miele ◽  
...  

Abstract Notch and its ligands have been implicated in the regulation and differentiation of various CD4+ T-helper cells. Regulatory T cells (Tregs), which express the transcription factor Foxp3, suppress aberrant immune responses that are typically associated with autoimmunity or excessive inflammation. Previous studies have shown that transforming growth factor beta (TGFβ1) induces Foxp3 expression and a regulatory phenotype in peripheral T cells. Here, we show that pharmacologic inhibition of Notch signaling using γ-secretase inhibitor (GSI) treatment blocks (1) TGFβ1-induced Foxp3 expression, (2) the up-regulation of Foxp3-target genes, and (3) the ability to suppress naive T-cell proliferation. In addition, the binding of Notch1, CSL, and Smad to conserved binding sites in the foxp3 promoter can be inhibited by treatment with GSI. Finally, in vivo administration of GSI results in reduced Foxp3 expression and development of symptoms consistent with autoimmune hepatitis, a disease previously found to result from dysregulation of TGFβ signaling and regulatory T cells. Together, these findings indicate that the Notch and TGFβ signaling pathways cooperatively regulate Foxp3 expression and regulatory T-cell maintenance both in vitro and in vivo.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Sashwati Roy ◽  
Savita Khanna ◽  
Chandan K Sen

Background . Transforming growth factor beta-1 (TGFbeta-1) is a key cytokine implicated in the development of cardiac fibrosis following ischemia-reperfusion (IR) injury. The profibrotic effects of TGFbeta-1 are primarily attributable to the differentiation of cardiac fibroblasts (CF) to myofibroblasts. Previously, we have reported perceived hyperoxia (Circ Res 92:264 –71), sub-lethal reoxygenation shock during IR, induces differentiation of CF to myofibroblasts at the infarct site. The mechanisms underlying oxygen-sensitive induction of TGFbeta-1 mRNA remain to be characterized. Hypothesis . Fra2 mediates oxygen-induced TGFbeta-1 mRNA expression in adult cardiac fibroblasts. Methods. TGFbeta-1 mRNA expression in infarct tissue was investigated in an IR injury model. The left anterior descending coronary artery of mice was transiently occluded for 60 minutes followed by reperfusion to induce IR injury. Spatially resolved infarct and non-infarct tissues were collected at 0, 1, 3, 5, and 7 days post-IR using laser capture microdissection. TGFbeta-1 mRNA levels were measured using real-time PCR. To investigate the role of oxygen in the regulation of TGFbeta-1, we used our previously reported model of perceived hyperoxia where CF (from 5wks old mice) after isolation were cultured at 5%O 2 (physiological pO 2 ) followed by transferring them to 20%O 2 to induce hyperoxic insult. Results & Conclusions. In vivo, a significant increase (p<0.01; n=5) in TGFbeta-1 mRNA was observed at the infarct site already at day 1 post-IR. The levels continued to increase until day 7 post-IR. In vitro, exposure of CF to 20%O 2 hyperoxic insult induced TGFbeta-1 mRNA (p<0.001; n=4) and protein (p<0.01; n=4) expression. Using a TGFbeta-1 promoter-luciferase reporter and DNA binding assays, we collected first evidence that AP-1 and its component Fra2 as major mediators of oxygen-induced TGFbeta-1 expression. Exposure to 20%O 2 resulted in increased localization of Fra2 in nucleus. siRNA-dependent Fra-2 knock-down completely abrogated oxygen-induced TGFbeta1 expression. In conclusion, this study presents first evidence that Fra-2 is involved in inducible TGFbeta1 expression in CF. Fra2 was noted as being central in regulating oxygen-induced TGFbeta-1 expression.s


2020 ◽  
Vol 48 (6) ◽  
pp. 030006052092641
Author(s):  
Zhili Chen ◽  
Yuxi Chen ◽  
Jue Zhou ◽  
Yong Li ◽  
Changyao Gong ◽  
...  

Objective Inflammation is the primary mechanism of lung ischemia-reperfusion injury (LIRI) and neurologic factors can regulate inflammatory immune responses. Netrin-1 is an axonal guidance molecule, but whether Netrin-1 plays a role in LIRI remains unclear. Methods A mouse model of LIRI was established. Immunohistochemistry was used to detect expression of Netrin-1 and to enumerate macrophages and T cells in lung tissue. The proportion of regulatory T cells (Tregs) was assessed by flow cytometry. Levels of apoptosis were assessed by terminal deoxynucleotidyl transferase dUTP nick end staining. Results Numbers of macrophages and T cells in the lung tissues of mice with LIRI were elevated, while expression of netrin-1 was significantly decreased. Flow cytometry showed that the proportion of Tregs in mice with LIRI was significantly decreased. The proportion of Tregs among lymphocytes was positively correlated with netrin-1 expression. In vitro experiments showed that netrin-1 promoted an increase in Treg proportion through the A2b receptor. Animal experiments showed that netrin-1 could inhibit apoptosis and reduce T cell and macrophage infiltration by increasing the proportion of Tregs, ultimately reducing LIRI. Treg depletion using an anti-CD25 monoclonal antibody blocked the effects of netrin-1. Conclusion Netrin-1 reduced LIRI by increasing the proportion of Tregs.


2011 ◽  
Vol 208 (12) ◽  
pp. 2489-2496 ◽  
Author(s):  
Uri Sela ◽  
Peter Olds ◽  
Andrew Park ◽  
Sarah J. Schlesinger ◽  
Ralph M. Steinman

Foxp3+ regulatory T cells (T reg cells) effectively suppress immunity, but it is not determined if antigen-induced T reg cells (iT reg cells) are able to persist under conditions of inflammation and to stably express the transcription factor Foxp3. We used spleen cells to stimulate the mixed leukocyte reaction (MLR) in the presence of transforming growth factor β (TGF-β) and retinoic acid. We found that the CD11chigh dendritic cell fraction was the most potent at inducing high numbers of alloreactive Foxp3+ cells. The induced CD4+CD25+Foxp3+ cells appeared after extensive proliferation. When purified from the MLR, iT reg cells suppressed both primary and secondary MLR in vitro in an antigen-specific manner. After transfer into allogeneic mice, iT reg cells persisted for 6 mo and prevented graft versus host disease (GVHD) caused by co-transferred CD45RBhi T cells. Similar findings were made when iT reg cells were transferred after onset of GVHD. The CNS2 intronic sequence of the Foxp3 gene in the persisting iT reg cells was as demethylated as the corresponding sequence of naturally occurring T reg cells. These results indicate that induced Foxp3+ T reg cells, after proliferating and differentiating into antigen-specific suppressive T cells, can persist for long periods while suppressing a powerful inflammatory disease.


2004 ◽  
Vol 200 (3) ◽  
pp. 277-285 ◽  
Author(s):  
Michael R. Ehrenstein ◽  
Jamie G. Evans ◽  
Animesh Singh ◽  
Samantha Moore ◽  
Gary Warnes ◽  
...  

Regulatory T cells have been clearly implicated in the control of disease in murine models of autoimmunity. The paucity of data regarding the role of these lymphocytes in human autoimmune disease has prompted us to examine their function in patients with rheumatoid arthritis (RA). Regulatory (CD4+CD25+) T cells isolated from patients with active RA displayed an anergic phenotype upon stimulation with anti-CD3 and anti-CD28 antibodies, and suppressed the proliferation of effector T cells in vitro. However, they were unable to suppress proinflammatory cytokine secretion from activated T cells and monocytes, or to convey a suppressive phenotype to effector CD4+CD25− T cells. Treatment with antitumor necrosis factor α (TNFα; Infliximab) restored the capacity of regulatory T cells to inhibit cytokine production and to convey a suppressive phenotype to “conventional” T cells. Furthermore, anti-TNFα treatment led to a significant rise in the number of peripheral blood regulatory T cells in RA patients responding to this treatment, which correlated with a reduction in C reactive protein. These data are the first to demonstrate that regulatory T cells are functionally compromised in RA, and indicate that modulation of regulatory T cells by anti-TNFα therapy may be a further mechanism by which this disease is ameliorated.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 855-855
Author(s):  
Andrea Pellagatti ◽  
Martin Jädersten ◽  
Ann-Mari Forsblom ◽  
Helen Cattan ◽  
Birger Christensson ◽  
...  

Abstract The immunomodulatory drug lenalidomide induces cytogenetic remissions in 75% of patients with myelodysplastic syndrome (MDS) and del(5)(q31) through unknown mechanisms. We investigated the in vitro effects of lenalidomide on growth and maturation in differentiating erythroblasts from MDS patients with del(5)(q31) (n=13) and from healthy controls (n=10). Lenalidomide selectively inhibited growth of del(5q) erythroblasts, while not affecting normal cells, including cytogenetically normal cells from MDS del(5q) patients. The inhibitory effect was more pronounced in erythroid than in myeloid cells. In order to gain insight into the mode of action of lenalidomide and to identify the molecular targets of this drug, we have investigated the gene expression profiles of the lenalidomide-treated and untreated intermediate erythroblasts from MDS del(5q) patients (n=9) and from healthy controls (n=8). GeneChip Human Genome U133 Plus 2.0 arrays (Affymetrix), covering over 47,000 transcripts representing 39,000 human genes, were used. Treatment with lenalidomide significantly influenced the pattern of gene expression in del(5q) intermediate erythroblasts, with up-regulation of VSIG4, PPIC, TPBG, and SPARC in all samples, and down-regulation of many genes involved in erythropoiesis, including HBA2, GYPA, and KLF1, in most samples. Up-regulation of SPARC (median 4.4-fold, range 2.4–9.5) is of particular interest since SPARC, a gene with known tumor suppressor functions, is both anti-proliferative and anti-angiogenic, and is located at 5q31–q32, within the commonly deleted region in MDS 5q- syndrome. Activin A was one of the most significant differentially expressed genes between lenalidomide-treated cells of MDS del(5q) patients and healthy controls. Activin A is a member of the transforming growth factor-beta superfamily, with pleiotropic functions including apoptosis of hemopoietic cells. We conclude that lenalidomide specifically inhibits growth of del(5q) erythroid progenitors, while not affecting cytogenetically normal cells. These novel findings suggest that up-regulation of SPARC and Activin A may underlie the potent effects of lenalidomide, in particular growth inhibition and anti-angiogenesis, in MDS with del(5)(q31). The localization of the SPARC gene to the CDR of the 5q- syndrome is intriguing and, in relation to the findings of the present study, we suggest that SPARC may well play a role in the molecular pathogenesis of the 5q- syndrome.


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