IL-17C Mitigates Murine Acute Graft-vs.-Host Disease by Promoting Intestinal Barrier Functions and Treg Differentiation

Acute graft-vs.-host disease (aGVHD) is one of the major complications and results in high mortality after allogeneic hematopoietic stem cell transplantation (allo-HSCT). IL-17C is involved in many inflammatory immune disorders. However, the role of IL-17C in aGVHD remains unknown. Here we demonstrated that IL-17C deficiency in the graft significantly promoted alloreactive T cell responses and induced aggravated aGVHD compared with wildtype donors in a fully MHC-mismatched allo-HSCT model. In contrast, IL-17C overexpression ameliorated aGVHD. IL-17C deficiency increased intestinal epithelial permeability and elevated inflammatory cytokine production, leading to an enhanced aGVHD progression. Tregs was reduced in recipients of IL-17C−/− graft, whilst restored after IL-17C overexpression. Decreased Treg differentiation was abrogated after neutralizing IFN-γ, but not IL-6. Moreover, depletion of Tregs diminished the protective effect of IL-17C. Of note, patients with low IL-17C expression displayed higher aGVHD incidence together with poor overall survival, thereby IL-17C could be an independent risk factor for aGVHD development. Our results are the first demonstrating the protective role of IL-17C in aGVHD by promoting intestinal barrier functions and Treg differentiation in a MHC fully mismatched murine aGVHD model. IL-17C may serve as a novel biomarker and potential therapeutic target for aGVHD

Inhibition of Acute Graft-versus-Host Disease with Retention of Graft-versus-Tumor Effects by Dimethyl Fumarate

Acute graft-versus-host disease (aGVHD) remains a clinical challenge and a major source of morbidity and mortality following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Dimethyl fumarate (DMF), an activator of Nrf2, has been shown to have anti-inflammatory and immunomodulatory properties without significant immunosuppression. We therefore hypothesized that DMF could be potentially harnessed for the treatment of aGVHD with retention of graft-versus-tumor effect. In this study, we showed that DMF significantly inhibited alloreactive T cell responses in vitro in mixed lymphocyte reaction assay. Administration of DMF significantly alleviated the severity, histological damage, and the overall mortality of aGVHD in an MHC-mismatched aGVHD model. DMF administration reduced the activation and effector function of donor T cells in vitro and in vivo. In addition, DMF treatment upregulated antioxidant enzymes heme oxygenase-1 and glutathione S-transferase-α1 expressions. Furthermore, DMF treatment markedly increased the frequencies of Treg cells. Depletion of CD25+ cells in DMF recipients aggravated aGVHD mortality compared with IgG control recipients. DMF could promote Treg cell differentiation in a dose dependent manner by upregulating TGF-β expression in vitro. Most importantly, DMF administration preserved graft-versus-leukemia effect after bone marrow transplantation. In conclusion, our findings demonstrated DMF as a promising agent for the prevention of aGVHD after allo-HSCT

Inhibition of Acute Graft-versus-Host Disease with Retention of Graft-versus-Tumor Effects by Dimethyl Fumarate

10.3389/fimmu.2017.01605Frontiers in Immunology8NOV160

High stearic acid diet modulates gut microbiota and aggravates acute graft-versus-host disease

10.1038/s41392-021-00600-9Signal Transduction and Targeted Therapy6127

Characterizing the Tumor Suppressor Role of CEACAM1 in Multiple Myeloma

Background/Aims: Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1), also known as CD66a, is a member of the immunoglobulin (Ig) superfamily that belongs to the carcinoembryonic antigen (CEA) family which plays a dual role in cancer. Previous studies showed high expression of CEACAM1 in multiple myeloma (MM). The aim of this study was to investigate the biological consequences of CEACAM1 overexpression in MM. Methods: pEGFP-N1-CEACAM1 and pcDNA3.1-CEACAM1 expression plasmids were transfected into U-266 and RPMI8266 cell lines . Effect of CEACAM1 overexpression on the proliferation of two cell lines were tested by the CCK8 assay. Cell cycle and Apoptotic changes after CEACAM1 transfection were examined with AnnexinV–FITC/PI by flow cytometry. Hochest staining assay was used to confirm the apoptotic changes. Caspase-3 activity was examined by Western blotting. The cell invasion and migration activity change after CEACAM1 transfection were performed by well chamber assays and a wound healing, respectively. MMP-2 and MMP-9 proteins expression were detected by Western blotting. Flow cytometry immunophenotyping was be evaluated on myeloma cells from bone marrow taken from 50 patients with symptomatic MM newly diagnosed. The correlations between CEACAM1 expression levels and the clinical features across all groups were investigated. Results: CEACAM1 overexpression significantly suppressed MM cell proliferation, induced cell apoptosis, and inhibited cell invasion and migration possibly through activation of caspase-3 and downregulation of MMP-2 and MMP-9. CEACAM1 expression in patients with DS stage I was more frequent (61.5%) than those with DS stage II (21.1%) or III (22.2%). Furthermore, patients with β2-microglobulin levels equal to or less than 3.5 mg/L had higher CEACAM1 expression than those with β2-microglobulin levels greater than 3.5 mg/L. Conclusion: Our findings suggest that CEACAM1 may act as a tumor suppressor in MM