Endometrial regenerative cells with galectin-9 high-expression attenuate experimental autoimmune hepatitis

Background Autoimmune hepatitis (AIH) is a T cell-mediated immune disease that activates abnormally against hepatic antigens. We have previously reported that endometrial regenerative cells (ERCs) were a novel source of adult stem cells, which exhibiting with powerful immunomodulatory effects. Galectin-9 (Gal-9) is expressed in ERCs and plays an important role in regulating T cell response. This study aims to explore the role of ERCs in attenuation of AIH and to determine the potential mechanism of Gal-9 in ERC-mediated immune regulation. Methods ERCs were obtained from menstrual blood of healthy female volunteers. In vitro, ERCs were transfected with lentivirus vectors carrying LGALS9 gene and encoding green fluoresce protein (GFP-Gal-9-LVs) at a MOI 50, Gal-9 expression in ERCs was detected by ELISA and Q-PCR. CD4+ T cells isolated from C57BL/6 mouse spleen were co-cultured with ERCs. The proliferation of CD4+ T cells was detected by CCK-8 kit and the level of Lck/zap-70/LAT protein was measured by western blot. Furthermore, AIH was induced by ConA in C57BL/6 mice which were randomly assigned to untreated, unmodified ERC-treated and Gal-9 high-expressing ERC-treated groups. Histopathological score, liver function, CD4+/CD8+ cell infiltration in liver tissues, the proportion of immune cells in the spleen and liver, and ERC tracking were performed accordingly to assess the progression degree of AIH. Results After transfecting with GFP-Gal-9-LVs, Gal-9 expression in ERCs was significantly increased. Additionally, Gal-9 high-expressing ERCs effectively inhibited CD4+ T cell proliferation and downregulated CD4+ T cell active related proteins p-Lck/p-ZAP70/p-LAT in vitro. Furthermore, treatment with Gal-9 high-expressing ERCs restored liver function, ameliorated liver pathological damage, inhibit CD4+ and CD8+ T cell proliferation and suppress Th1 and Th17 cell response in the hepatitis mice. In addition, Gal-9 high-expressing ERCs further markedly enhanced the level of IL-10 but reduced the levels of IFN-γ, TNF-α, and IL-4 in mouse sera and liver. Cell tracking also showed that ERCs could migrate to the damaged liver organs. Conclusions The results suggested that Gal-9 was an essential modulator, which was required by ERCs in regulating T cell response and attenuating ConA-induced experimental hepatitis. And also, it provides a novel idea for the clinical treatment of AIH.

IL-1β pre-stimulation enhances the therapeutic effects of endometrial regenerative cells on experimental colitis

Background Ulcerative colitis (UC) is a chronic, relapsing, and non-specific inflammatory bowel disease, and the current treatment strategies were mainly used to relieve symptoms or for maintenance. Endometrial regenerative cells (ERCs) are mesenchymal-like stromal cells and have been demonstrated to alleviate multiple immune-dysregulation diseases. Pro-inflammatory stimuli were reported to enhance the immunosuppressive functions of ERCs, but the mechanism underlined is not fully understood. Here, we have designed this study to investigate the therapeutic effects of IL-1β-primed ERCs in the attenuation of experimental colitis. Methods BALB/c mice were given 3% dextran sodium sulfate (DSS) for 7 consecutive days and free tap water for 3 days sequentially to induce experimental colitis. PBS (200 μL), ERCs, and IL-1β-primed ERCs (10ng/mL, 48 h) were injected (1 million/mouse/day, i.v.) on day 2, 5, and 8, respectively. Colonic and splenic samples were harvested on day 10 after DSS induction. Results It was found that IL-1β-primed ERC treatment markedly attenuated colonic damage, body weight loss, and colon length shortening in colitis mice. Compared with other treatments, cell populations of CD4+IL-4+Th2 cells, CD4+CD25+FOXP3+ regulatory T cells (Tregs), and CD68+CD206+ macrophages in spleens were also significantly upregulated in the IL-1β-primed ERC-treated group (p < 0.05). In addition, lower expression of pro-inflammatory (IFN-γ, IL-17, TNF-α, and IL-6), but higher levels of anti-inflammatory cytokines (IL-4 and IL-10) were detected in colons in the IL-1β-primed ERC-treated group (p < 0.05 vs. other groups). Importantly, we also found that different generations of ERCs had an overall lower secretion of Dickkopf-1 (DKK1) by IL-1β pre-stimulation (p < 0.05) and a higher expression of β-catenin in colonic and splenic tissues after the administration of IL-1β-primed ERCs. Conclusions This study has demonstrated that IL-1β pre-stimulation effectively downregulated DKK1 expression in ERCs, which in turn promoted the wnt/β-catenin pathway activation in colonic and splenic tissues. Consequently, IL-1β-primed ERCs exhibited an enhanced therapeutic effect in the attenuation of DSS-induced colitis.

Galectin-9 is required for endometrial regenerative cells to induce long-term cardiac allograft survival in mice

Background Endometrial regenerative cells (ERCs), a novel type of mesenchymal-like stem cells, were identified as an attractive candidate for immunoregulation and induction of cardiac allograft tolerance. However, the underlying mechanisms of ERCs in immune regulation still remain largely unclear. The present study is designed to determine whether the expression of Galectin-9 (Gal-9), a soluble tandem-repeat member of the galectin family, is crucial for ERC-based immunomodulation. Methods In this study, we measured Gal-9 expression on ERCs and then co-cultured Gal-9-ERCs, ERCs, and ERCs+lactose (Gal-9 blocker) with activated C57BL/6-derived splenocytes. Furthermore, we performed mouse heart transplantation between BALB/c (H-2d) donor and C57BL/6 (H-2b) recipient. ERCs were administrated 24 h after the surgery, either alone or in combination with rapamycin. Results Our data demonstrate that ERCs express Gal-9, and this expression is increased by IFN-γ stimulation in a dose-dependent manner. Moreover, both in vitro and in vivo results show that Gal-9-ERC-mediated therapy significantly suppressed Th1 and Th17 cell response, inhibited CD8+ T cell proliferation, abrogated B cell activation, decreased donor-specific antibody production, and enhanced the Treg population. The therapeutic effect of ERCs was further verified by their roles in prolonging cardiac allograft survival and alleviating graft pathological changes. Conclusions Taken together, these data indicate that Gal-9 is required for ERC-mediated immunomodulation and prevention of allograft rejection.

Downregulation of Dickkopf-1 Augments the Therapeutic Effects of Endometrial Regenerative Cells on Experimental Colitis

Background We have demonstrated that endometrial regenerative cells (ERCs) are mesenchymal-like stromal cells and can attenuate experimental colitis, however, its underlying mechanism needs further investigation. Dickkopf-1 (DKK1), a glucoprotein secreted by mesenchymal stromal cells (MSCs), is a classical inhibitor of Wnt/β-catenin pathway which is closely associated with the development of colitis. Therefore, the objective of this study was to investigate whether ERCs could also secret DKK1, and whether the downregulation of DKK1 (DKK1 low -ERCs) would enhance the therapeutic effects of ERCs in attenuation of experimental colitis. Methods BALB/c mice were given 3% dextran sodium sulfate (DSS) for 7 consecutive days and free tap water for 3 days sequentially to induce experimental colitis. Unmodified ERCs, IL-1β-treated ERCs (DKK1 low -ERCs) and glucocorticoid-treated ERCs (DKK1 high -ERCs) were injected (1 million/mouse/day, i.v. ) on day 2, 5 and 8 respectively. Colonic and splenic samples were harvested on day 10 after DSS-induction. Results It was found that DKK1 low -ERC treatment markedly attenuated colonic damage, body weight loss and colon-length shortening in colitis mice. Compared with other treatments, cell populations of CD4 + IL-4 + Th2, CD4 + CD25 + FOXP3 + Treg, and CD68 + CD206 + macrophages in spleens were also significantly upregulated in DKK1 low -ERC group ( p < 0.05). In addition, lower expression of pro-inflammatory (TNF-α and IFN-γ), but higher levels of anti-inflammatory cytokines (IL-4 and IL-10) and β-catenin were detected in colons in DKK1 low -ERC group ( p < 0.01 vs. other groups). Conclusions DKK1 low -ERCs display augmented immunoregulatory ability and therapeutic effects in DSS-induced colitis.

Downregulation of Dickkopf-1 Augments the Therapeutic Effects of Endometrial Regenerative Cells on Experimental Colitis

Background We have demonstrated that endometrial regenerative cells (ERCs) are mesenchymal-like stromal cells and can attenuate experimental colitis, however, its underlying mechanism needs further investigation. Dickkopf-1 (DKK1), a glucoprotein secreted by mesenchymal stromal cells (MSCs), is a classical inhibitor of Wnt/β-catenin pathway which is closely associated with the development of colitis. Therefore, the objective of this study was to investigate whether ERCs could also secret DKK1, and whether the downregulation of DKK1 (DKK1low-ERCs) would enhance the therapeutic effects of ERCs in attenuation of experimental colitis. Methods BALB/c mice were given 3% dextran sodium sulfate (DSS) for 7 consecutive days and free tap water for 3 days sequentially to induce experimental colitis. Unmodified ERCs, IL-1β-treated ERCs (DKK1low-ERCs) and glucocorticoid-treated ERCs (DKK1high-ERCs) were injected (1 million/mouse/day, i.v.) on day 2, 5 and 8 respectively. Colonic and splenic samples were harvested on day 10 after DSS-induction. Results It was found that DKK1low-ERC treatment markedly attenuated colonic damage, body weight loss and colon-length shortening in colitis mice. Compared with other treatments, cell populations of CD4+IL-4+Th2, CD4+CD25+FOXP3+Treg, and CD68+CD206+macrophages in spleens were also significantly upregulated in DKK1low-ERC group (p < 0.05). In addition, lower expression of pro-inflammatory (TNF-α and IFN-γ), but higher levels of anti-inflammatory cytokines (IL-4 and IL-10) and β-catenin were detected in colons in DKK1low-ERC group (p < 0.01 vs. other groups). Conclusions DKK1low-ERCs display augmented immunoregulatory ability and therapeutic effects in DSS-induced colitis.

Stromal Cell-Derived Factor-1 Enhances the Therapeutic Effects of Human Endometrial Regenerative Cells in a Mouse Sepsis Model

Endometrial regenerative cells (ERCs) are mesenchymal-like stromal cells obtained from human menstrual blood, whose positive therapeutic effects have been validated in several experimental models. Stromal cell-derived factor-1 (SDF-1), the ligand for CXCR4, plays an important role in the migration of mesenchymal stromal cells. The purpose of this study was to investigate the role of the SDF-1/CXCR4 pathway in the therapeutic effects of ERCs in a mouse sepsis model. Through preexperiment and confirmation, wild-type C57BL/6 mice were intraperitoneally injected with 10 mg/kg lipopolysaccharide (LPS). The therapeutic effects of ERCs with different pretreatments were evaluated by assessing sepsis-related symptoms, detecting tissue damage and measuring levels of inflammatory and oxidative stress-related factors. The in vitro experiments demonstrated that there was a much higher CXCR4 expression on ERCs when they were cocultured with SDF-1. The ex vivo experiment results showed that SDF-1 expression significantly increased in mouse tissues. Further experiments also confirmed that, compared with the unmodified ERC treatment group, SDF-1 pretreatment significantly enhanced the therapeutic effects of ERCs on alleviating sepsis symptoms, ameliorating pathological changes, reducing Bax level, and increasing Bcl-2 and PCNA expressions in mouse liver tissues. Furthermore, it was also found that SDF-1-pretreated ERCs contributed to reducing the levels of proinflammatory cytokines (TNF-α, IL-1β) and increasing the levels of anti-inflammatory factors (IL-4, IL10) in mouse serum, liver, and lung. Moreover, SDF-1-pretreated ERCs could also significantly decrease the levels of iNOS and MDA and increase the expression of Nrf2, HO-1, and SOD in liver tissues. Taken together, these results indicate that SDF-1 pretreatment plays a key role in improving the therapeutic effects of ERCs in alleviating sepsis-related symptoms, reducing tissue damage, regulating inflammatory imbalance, and relieving oxidative stress in a mouse sepsis model, which provides more possibilities for the clinical application of ERCs in sepsis and relevant diseases.