scholarly journals Regulatory T Cells Improved the Anti-cirrhosis Activity of Human Amniotic Mesenchymal Stem Cell in the Liver by Regulating the TGF-β-Indoleamine 2,3-Dioxygenase Signaling

Author(s):  
Zhenhua Deng ◽  
Jinren Zhou ◽  
Xiaoxin Mu ◽  
Jian Gu ◽  
Xiangyu Li ◽  
...  

Liver fibrosis is a progression stage of chronic liver disease, while current therapies cannot cure or attune cirrhosis effectively. Human amniotic mesenchymal stromal cell (hAMSC) presented immunoregulatory and tissue repairability of multiple illnesses. Regulatory T cells (Treg) had been proved to be functional in reducing immune cell activity. We showed that co-infusion of hAMSC and Treg prevented mild liver fibrosis comparing with hAMSC or Treg alone group. In vitro study indicated that the addition of Treg or the supernatant of Treg improved the hepatocyte growth factor (HGF) secreting and cell differentiation ability of hAMSC. Reduction of TGF-β significantly decreased the HGF secreting and differentiation of hAMSC. Multiple signal neutralizers were added to the culture to understand further the mechanism, which showed that 1-MT, the suppressor of Indoleamine 2,3-dioxygenase (IDO), was involved in the effect of TGF-β in regulating hAMSC. Depletion of TGF-β or IDO signaling successfully abolished the effect of Treg in improving hAMSC’s function both in vitro and vivo. Finally, our result indicated that Treg improved the function of hAMSC by regulating the TGF-β-IDO signaling and co-infusion of hAMSC and Treg provided a promising approach for treating liver cirrhosis.

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Atar Lev ◽  
Amos J. Simon ◽  
Luba Trakhtenbrot ◽  
Itamar Goldstein ◽  
Meital Nagar ◽  
...  

Introduction. Patients with severe combined immunodeficiency (SCID) may present with residual circulating T cells. While all cells are functionally deficient, resulting in high susceptibility to infections, only some of these cells are causing autoimmune symptoms.Methods. Here we compared T-cell functions including the number of circulating CD3+T cells,in vitroresponses to mitogens, T-cell receptor (TCR) repertoire, TCR excision circles (TREC) levels, and regulatory T cells (Tregs) enumeration in several immunodeficinecy subtypes, clinically presenting with nonreactive residual cells (MHC-II deficiency) or reactive cells. The latter includes patients with autoreactive clonal expanded T cell and patients with alloreactive transplacentally maternal T cells.Results. MHC-II deficient patients had slightly reduced T-cell function, normal TRECs, TCR repertoires, and normal Tregs enumeration. In contrast, patients with reactive T cells exhibited poor T-cell differentiation and activity. While the autoreactive cells displayed significantly reduced Tregs numbers, the alloreactive transplacentally acquired maternal lymphocytes had high functional Tregs.Conclusion. SCID patients presenting with circulating T cells show different patterns of T-cell activity and regulatory T cells enumeration that dictates the immunodeficient and autoimmune manifestations. We suggest that a high-tolerance capacity of the alloreactive transplacentally acquired maternal lymphocytes represents a toleration advantage, yet still associated with severe immunodeficiency.


2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Yejin Xu ◽  
Xinyue Tang ◽  
Min Yang ◽  
Shengguo Zhang ◽  
Shanshan Li ◽  
...  

Aim. To explore the therapeutic effects and mechanisms of interleukin 10 gene-modified bone marrow-derived dendritic cells (DC-IL10) on liver fibrosis. Methods. In vitro, BMDCs were transfected with lentiviral-interleukin 10-GFP (LV-IL10-GFP) at the MOI of 1 : 40. Then, the phenotype (MHCII, CD80, and CD86) and allo-stimulatory ability of DC-IL10 were identified by flow cytometry, and the levels of IL-10 and IL-12 (p70) secreted into the culture supernatants were quantified by ELISA. In vivo, DC-IL10 was injected into mice with CCl4-induced liver fibrosis through the tail vein. Lymphocytes were isolated to investigate the differentiation of T cells, and serum and liver tissue were collected for biochemical, cytokine, histopathologic, immune-histochemical, and Western blot analyzes. Results. In vitro, the expressions of MHCII, CD80, and CD86 in DC-IL10 were significantly suppressed, allogeneic CD4+T cells incubated with DC-IL10 showed a lower proliferative response, and the levels of IL-10 and IL-12 (p70) secreted into the DC-IL10 culture supernatants were significantly increased and decreased, respectively. In vivo, regulatory T cells (Tregs) were significantly increased, while ALT, AST, and inflammatory cytokines were significantly reduced in the DC-IL10 treatment group, and the degree of hepatic fibrosis was obviously reversed. The TGF-β/smad pathway was inhibited following DC-IL10 treatment compared to the liver fibrosis group. Conclusion. IL-10 genetic modification of BMDCs may maintain DC in the state of tolerance and allow DC to induce T cell hyporesponsiveness or tolerance. DC-IL10 suppressed liver fibrosis by inducing Treg production and inhibiting the TGF-β/smad signaling pathway.


2009 ◽  
Vol 84 (2) ◽  
pp. 883-893 ◽  
Author(s):  
Devin B. Lowe ◽  
Michael H. Shearer ◽  
Cynthia A. Jumper ◽  
Robert K. Bright ◽  
Ronald C. Kennedy

ABSTRACT The required activities of CD4+ T cells and antibody against the virally encoded oncoprotein simian virus 40 (SV40) Tag have previously been demonstrated by our laboratory to be mediators in achieving antitumor responses and tumor protection through antibody-dependent cell-mediated cytotoxicity (ADCC). In this study, we further characterize the necessary immune cell components that lead to systemic tumor immunity within an experimental pulmonary metastatic model as the result of SV40 Tag immunization and antibody production. Immunized animals depleted of CD8+ T cells at the onset of experimental tumor cell challenge developed lung tumor foci and had an overall decreased survival due to lung tumor burden, suggesting a role for CD8+ T cells in the effector phase of the immune response. Lymphocytes and splenocytes harvested from SV40 Tag-immunized mice experimentally inoculated with tumor cells synthesized increased in vitro levels of the Th1 cytokine gamma interferon (IFN-γ), as assessed by enzyme-linked immunosorbent assay (ELISA) and flow cytometry assays. CD8+ T-cell activity was also heightened in SV40 Tag-immunized and tumor cell-challenged mice, based upon intracellular production of perforin, confirming the cytolytic properties of CD8+ T cells against tumor cell challenge. Altogether, these data point to the role of recombinant SV40 Tag protein immunization in initiating a cytotoxic T-lymphocyte (CTL) response during tumor cell dissemination and growth. The downstream activity of CD8+ T cells within this model is likely initiated from SV40 Tag-specific antibody mediating ADCC tumor cell destruction.


2016 ◽  
Vol 311 (2) ◽  
pp. G313-G323 ◽  
Author(s):  
Gregory Noel ◽  
Muhammad Imran Arshad ◽  
Aveline Filliol ◽  
Valentine Genet ◽  
Michel Rauch ◽  
...  

The IL-33/ST2 axis plays a protective role in T-cell-mediated hepatitis, but little is known about the functional impact of endogenous IL-33 on liver immunopathology. We used IL-33-deficient mice to investigate the functional effect of endogenous IL-33 in concanavalin A (Con A)-hepatitis. IL-33−/− mice displayed more severe Con A liver injury than wild-type (WT) mice, consistent with a hepatoprotective effect of IL-33. The more severe hepatic injury in IL-33−/− mice was associated with significantly higher levels of TNF-α and IL-1β and a larger number of NK cells infiltrating the liver. The expression of Th2 cytokines (IL-4, IL-10) and IL-17 was not significantly varied between WT and IL-33−/− mice following Con A-hepatitis. The percentage of CD25+ NK cells was significantly higher in the livers of IL-33−/− mice than in WT mice in association with upregulated expression of CXCR3 in the liver. Regulatory T cells (Treg cells) strongly infiltrated the liver in both WT and IL-33−/− mice, but Con A treatment increased their membrane expression of ST2 and CD25 only in WT mice. In vitro, IL-33 had a significant survival effect, increasing the total number of splenocytes, including B cells, CD4+ and CD8+ T cells, and the frequency of ST2+ Treg cells. In conclusion, IL-33 acts as a potent immune modulator protecting the liver through activation of ST2+ Treg cells and control of NK cells.


Author(s):  
Yinjiang Zhang ◽  
Hongyun Wei ◽  
Lu Fan ◽  
Mingyan Fang ◽  
Xu He ◽  
...  

Immunosuppressive tumor microenvironment in hepatocellular carcinoma (HCC) is critical in tumor development. C-type (Ca2+ -dependent) lectin (CLEC) receptors, essential in innate pattern recognition, have potential regulatory effects on immune cell trafficking and modulatory effects on cancer cell activity. However, information on the expression and prognostic value of CLECs in HCC is scanty. Herein, we explored the potential role of CLECs in HCC based on TCGA, ONCOMINE, GEPIA, UALCAN, cBioPortal, Metascape, TRRUST, and TIMER databases. Results demonstrated a significantly higher mRNA level of CLEC4A and CLEC4L in HCC tissues than normal liver tissues. Contrarily, we found significantly low CLEC4G/H1/H2/M expression in HCC tissues. The IHC analysis revealed the following: Absence of CLEC4A/J/K/M in normal and liver cancer tissues; high CLEC4C expression in HCC tissues; low expression and zero detection of CLEC4D/E/H1/H2/L in HCC tissues and normal tissues, respectively. And the HepG2 and LX-2 were used to verify the expression level of CLEC4s via qRT-PCR in vitro. Furthermore, the expression of CLEC4H1 (ASGR1) and CLEC4H2 (ASGR2) exhibited a significant relation to clinical stages. However, the expression of CLEC4A, CLEC4D, CLEC4E, CLEC4J (FCER2), CLEC4K (CD207), CLEC4G, CLEC4H1, CLEC4M, and CLEC4H2 decreased with tumor progression. Patients expressing higher CLEC4H1/H2 levels had longer overall survival than patients exhibiting lower expression. Moreover, CLEC4A/D/E/J/K/G/H1/M/H2 had significant down-regulated levels of promoter methylation. The expression level of CLEC4s was correlated with the infiltration of B cells, CD8 + T cells, CD4 + T cells, macrophage cells, neutrophil cells, and dendritic cells. Functional analysis revealed the potential role of CLECL4s in virus infection, including COVID-19. Also, hsa-miR-4278 and hsa-miR-324-5p, two potential miRNA targets of CLEC4s, were uncovered. This article demonstrates that CLEC4 is crucial for the development of HCC and is associated with infiltration of various immune cells, providing evidence for new immunotherapy targets in HCC.


Blood ◽  
2015 ◽  
Vol 126 (23) ◽  
pp. 502-502 ◽  
Author(s):  
Yawara Kawano ◽  
Michele Moschetta ◽  
Katsutoshi Kokubun ◽  
Pavlo Lukyanchykov ◽  
Esilida Sula Karreci ◽  
...  

Abstract Introduction. Growing evidence suggests that immune cells that reside within the tumor microenvironment are dysregulated and functionally impaired, leading to defective anti-tumor immunity of the host. One of the major immunosuppressive mechanisms during tumor progression is expansion of regulatory immune cells. Here, we analyzed the immune cells within the bone marrow (BM) and the peripheral blood (PB) of 2 immunocompetent multiple myeloma (MM) mouse models. We next studied the role of regulatory T cells (Tregs) in MM pathogenesis. Materials and methods. To study the immune cell populations of the BM and PB, we used two immuncompetent mouse models and transplanted VK*MYC cells or 5TGM1 cells into C57BL/6 and C57BL/Kalwrij mice respectively. The immune cell populations and checkpoint receptor expressions were analyzed by CyTOF mass cytometer or flow-cytometry. Treg induction assay was performed in vitro to study the mechanism of Treg increase in the BM of myeloma injected mice. CD4+ CD25- cells were obtained from C57BL/Kalwrij mice and were co-cultured with 5TGM1 cells or B cells from C57BL/Kalwrij mice in vitro. Treg induction was compared by flow-cytometry. Transplantable VK*MYC cells were injected into "depletion of regulatory T cell" (DEREG) mice, which expresses a simian diphtheria toxin (DT) receptor-enhanced GFP fusion protein under the control of the FOXP3 gene locus, or their wild type littermates. DT injection into these mice leads to depletion of Tregs as previously described (J Exp Med. 2007; 204: 57-63). DT was given once every week for a total 3 times i.p to the DEREG mice or the littermate controls to specifically deplete Tregs and to study the role of Tregs during MM progression. Tregs (CD4+ FOXP3-GFP+ cells) were sorted from VK*MYC injected mice or non-injected DEREG mice BM using FACSAria cell sorter. Cells isolated were subjected to RNA sequencing. Gene Set Enrichment Analysis (GSEA) was performed to define differences in molecular signatures between MM-associated and normal Tregs. Results. The Treg proportion was significantly increased within the CD4+ T cells in the BM of myeloma cell injected mice from the early stage of disease compared to control mice, while in the PB, the increase was observed only at the late stages of disease progression. The effector T cell (Teff)/Treg ratio was significantly decreased in the BM at the end-stage myeloma bearing mice (P<0.01). Checkpoint related molecules (PD-1, LAG-3 and Tim-3) on Tregs and Teffs were up-regulated at the protein level in the BM of myeloma injected mice compared to control (P<0.01). These data indicate the activation of Tregs and decrease of Teff activity, leading to suppression of anti-myeloma T cell activity in the MM BM. Under in vitro co-culture conditions, 5TGM1 cells induced a significant increase in the number of Tregs from non-Treg CD4+ T cells compared to controls (P<0.01). 5TGM1 cell-induced Tregs presented with enhanced ki-67 expression, thus suggesting the ability of MM cells to induce Treg proliferation. Additionally, the trans-well co-culture experiment showed that the major mechanism for Treg induction by 5TGM1 was by direct contact with T cells rather than secreting factors. Significant increase in survival was observed in the VK*MYC injected DEREG mice under Treg depletion compared to the DEREG mice without Treg depletion and wild type littermates under DT treatment (P<0.001). The Treg depleted DEREG mice were accompanied with an increase of Teffs (P<0.01), indicating recovery of anti-myeloma T cell activity. RNA sequencing of BM Tregs from VK*MYC injected mice showed increased expression of immune checkpoint related molecules and increased Treg effector molecules (IL-10, Granzyme B) compared to BM Tregs from control mice, indicating a more functionally active phenotype of VK*MYC associated Tregs. GSEA showed an enrichment of genes involved in type-1 interferon signaling in VK*MYC associated Tregs. Conclusions. We used 2 immunocompetent MM mouse models to study the characterization and significance of Tregs in MM progression. CyTOF analysis and RNA sequencing data indicated Treg activation in the MM BM microenvironment. The Treg in vivo depletion experiment showed that Tregs have a significant role in MM progression. These data indicate that immunotherapy targeting Tregs may represent a novel therapeutic strategy for MM. Studies are ongoing to understand the roles of Tregs in human MM patients. Disclosures No relevant conflicts of interest to declare.


1983 ◽  
Vol 158 (4) ◽  
pp. 1048-1060 ◽  
Author(s):  
G Tosato ◽  
S E Pike ◽  
R M Blaese

Epstein-Barr virus-induced infectious mononucleosis (IM) is associated with the activation of suppressor T lymphocytes that profoundly inhibit immunoglobulin (Ig) production in vitro. We have examined the nature of signals operating in the interaction between IM suppressor T cells and their targets, and explored the possibility that a lectin-like receptor molecule and its specific sugar might provide specificity to this interaction. When D-mannose or some of its derivatives, including alpha-methyl-D-mannoside, mannose-6-phosphate, and mannan, were added to suppressed cultures containing IM T lymphocytes and pokeweed mitogen (PWM)-stimulated normal mononuclear cells, a significant enhancement of Ig production was observed. These sugars had little or no effect on Ig production by the PWM-stimulated responder cells alone and thus the enhanced Ig production could be attributed to the reversal of suppression in the co-cultures by these sugars. This was further confirmed by the observation that the sugars were effective only if present during the first 24 h of culture, a time when IM suppressor T cells exert their principal effect. The effect of sugars on Ig production by suppressed cultures was similar to that achieved by decreasing by about fourfold the number of IM T cells in culture. The effect of the sugars is unlikely to represent a form of nonspecific toxicity, since inhibited cultures become responders in the presence of the sugar. Furthermore, toxicity restricted to the suppressor T cells is unlikely, since preincubation of the T cells with the sugars did not reduce their subsequent ability to suppress in secondary indicator cultures. In addition, there was no correlation between the effect of the sugars on T cell proliferation and their effect on T cell-mediated suppression. The reversal of suppression by sugars was dose dependent and demonstrated stereo-specificity in that L-mannose was without effect while D-mannose reversed suppression. These data indicate that D-mannose and some of its derivatives consistently reverse suppression of Ig production by IM T cells and strongly suggest a role for saccharides as critical components in the cellular receptors involved in certain physiologic immune cell interactions.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Jian Lu ◽  
Weiwei Wang ◽  
Peiyuan Li ◽  
Xiaodong Wang ◽  
Chao Gao ◽  
...  

AbstractRegulatory T cells (Tregs), which characteristically express forkhead box protein 3 (Foxp3), are essential for the induction of immune tolerance. Here, we investigated microRNA-146a (miR-146a), a miRNA that is widely expressed in Tregs and closely related to their homeostasis and function, with the aim of enhancing the function of Tregs by regulating miR-146a and then suppressing transplant rejection. The effect of the absence of miR-146a on Treg function in the presence or absence of rapamycin was detected in both a mouse heart transplantation model and cell co-cultures in vitro. The absence of miR-146a exerted a mild tissue-protective effect by transiently prolonging allograft survival and reducing the infiltration of CD4+ and CD8+ T cells into the allografts. Meanwhile, the absence of miR-146a increased Treg expansion but impaired the ability of Tregs to restrict T helper cell type 1 (Th1) responses. A miR-146a deficiency combined with interferon (IFN)-γ blockade repaired the impaired Treg function, further prolonged allograft survival, and alleviated rejection. Importantly, miR-146a regulated Tregs mainly through the IFN-γ/signal transducer and activator of transcription (STAT) 1 pathway, which is implicated in Treg function to inhibit Th1 responses. Our data suggest miR-146a controls a specific aspect of Treg function, and modulation of miR-146a may enhance Treg efficacy in alleviating heart transplant rejection in mice.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Feng Wang ◽  
Bryant Chau ◽  
Sean M. West ◽  
Christopher R. Kimberlin ◽  
Fei Cao ◽  
...  

AbstractGlucocorticoid-induced tumor necrosis factor receptor-related protein (GITR) and GITR ligand (GITRL) are members of the tumor necrosis superfamily that play a role in immune cell signaling, activation, and survival. GITR is a therapeutic target for directly activating effector CD4 and CD8 T cells, or depleting GITR-expressing regulatory T cells (Tregs), thereby promoting anti-tumor immune responses. GITR activation through its native ligand is important for understanding immune signaling, but GITR structure has not been reported. Here we present structures of human and mouse GITR receptors bound to their cognate ligands. Both species share a receptor–ligand interface and receptor–receptor interface; the unique C-terminal receptor–receptor enables higher order structures on the membrane. Human GITR–GITRL has potential to form a hexameric network of membrane complexes, while murine GITR–GITRL complex forms a linear chain due to dimeric interactions. Mutations at the receptor–receptor interface in human GITR reduce cell signaling with in vitro ligand binding assays and minimize higher order membrane structures when bound by fluorescently labeled ligand in cell imaging experiments.


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