Human Amniotic Mesenchymal Stem Cells Inhibit aGVHD by Regulating Balance of Treg and T Effector Cells

Abstract

Background Acute graft versus host disease (aGVHD) remains a leading cause of transplant-related mortality following allogeneic haematopoietic cell transplantation (allo-HCT). Human amniotic mesenchymal stem cells (hAMSCs) are a novel mesenchymal stem cells (MSCs), which have stronger proliferation and immunomodulatory ability compared with bone marrow mesenchymal stem cells (BM-MSCs). Besides, as the amniotic membrane is often treated as medical waste after delivery, hAMSCs can be obtained conveniently and noninvasively. The aim of this study was to explore the therapeutic efficacy and underlying mechanisms of hAMSCs transplantation for the humanized aGVHD mouse model. Methods We established a humanized aGVHD mouse model by transplanting human peripheral blood mononuclear cells (PBMCs) into NOD-Prkdc scid IL2rγ null (NPG) mice, human amniotic membrane collected from discarded placenta of healthy pregnant women after delivery and hAMSCs were extracted from amniotic membrane and expanded in vitro. Mice were divided into untreated group (Control), aGVHD group (aGVHD), and hAMSCs treatment group (aGVHD+hAMSCs), the hAMSCs labeled with GFP were administered to aGVHD mice to explore the homing ability of hAMSCs. T effector and regulatory T cells (Tregs) levels and cytokines of each group in target organs were detected by flow cytometry and cytometric bead array (CBA), respectively. Results We successfully established a humanized aGVHD mouse model using NPG mice. The hAMSCs have the ability to inhibit aGVHD in this mouse model through reduced villous blunting and lymphocyte infiltration of the gut while reducing inflammatory edema, tissue destruction and lymphocyte infiltration into the parenchyma of the liver and lung. hAMSCs suppressed CD3+CD4+ T and CD3+CD8+ T cell expression and increased the proportion of Tregs, and besides, hAMSCs can reduce the levels of IL-17A, INF-γ, and TNF in aGVHD target organs. Conclusion The NPG murine environment was capable of activating human T cells to produce aGVHD pathology to mimic aGVHD as in humans. The hAMSCs controlled aGVHD by decreasing inflammatory cytokine secretion within target organs by modulating the balance of Tregs and T effector cells in humanized mice.

Therapeutic Effects of HLA-G5 Overexpressing hAMSCs on aGVHD After Allo-HSCT: Involving in the Gut Microbiota at the Intestinal Barrier

“…The authors also declared that hAMSCs could mitigate aGVHD by regulating T cell immune balance in vivo. 11 Therefore, the author established hAMSCs overexpressing HLA-G5 to verify whether they have an effective therapy for aGVHD in vivo. A schematic of the animal experimental design is shown in Figure 3A , and examination of the expression of HLA-G5 protein in hAMSCs and lentivirus transfected hAMSCs through Western Blot and ELISA was shown in Figure S1 .…”

“…Humanized aGVHD mouse models induced by irradiation and human peripheral blood mononuclear cells (PBMCs) injection were constructed using an established protocol in our group. 11 Briefly, NPG mice were randomly divided into four groups, namely the Control group, aGVHD group, hAMSCs group and HLA-G5 group, and there were 14 mice in each group apart from 4 mice in the Control group. Mice in aGVHD, hAMSCs and HLA-G5 groups were irradiated followed by 3 × 10 6 PBMCs injection by tail vein after 3–4 h. On the third day after transplantation, mice in each group were given a tail vein infusion of 5 × 10 5 hAMSCs (hAMSCs group), 5 × 10 5 HLA-G5 overexpressing hAMSCs (HLA-G5 group) or 500 μL PBS (aGVHD group and Control group).…”

“… 9 Human amniotic mesenchymal stem cells (hAMSCs) are a type of novel MSCs derived from post-partum placenta, a medical waste, which could be obtained easily, massively and safely without invasive procedures and ethical or moral disputes compared with bone marrow mesenchymal stem cells (BM-MSCs), making them an ideal source of MSCs for GVHD therapy. 10 We have demonstrated that hAMSCs are yet a favorable therapeutic strategy beneficial to aGVHD, 11 and the gut microbiota could be altered after hAMSCs treatment, 12 but the mechanism remains unclear.…”

Insights into mechanisms of graft-versus-host disease through humanised mouse models

“…NPG (2 Gy) 3 × 10 6 (i.v.) CD45 + and CD3 + Blood, spleen, liver, lung and intestine Spleen, liver, lung and intestine (158) Abbreviations: NSG: NOD-scid-IL2Rγ null , NOG: NOD/Shi-scid-IL2Rγ null , NPG: NOD-Prkdc scid IL2rγ null , Gy: gray, PBMCs: peripheral blood mononuclear cells, i.v. : intravenous, i.p.…”

Mesenchymal Stem Cells and Their Small Extracellular Vesicles as Crucial Immunological Efficacy for Hepatic Diseases

“…MSCs/MSC-sEVs also induce Treg/Breg-cell differentiation. Promoting Treg differentiation (87) reverses the imbalance of T effector and Treg cells (88). MSC-sEVs induce differentiation through the miR-1246/Nfat5 axis (89) and the mTOR-mediated…”