ABSTRACT
Mesenchymal stem cells (MSCs) play an important role as immune modulator through interaction with several immune cells, including macrophages. In this study, the immunomodulatory potency of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) was demonstrated in the in vivo middle cerebral artery occlusion (MCAo)-induced brain injury rat model and in vitro THP-1-derived macrophages model. At 24 h after induction of MCAo, hUC-MSCs was administered via tail vein as a single dose. Remarkably, hUC-MSCs could inhibit M1 polarization and promote M2 polarization of microglia in vivo after 14 days induction of MCAo. Compared with THP-1-derived macrophages which had been stimulated by lipopolysaccharide, the secretion of proinflammatory cytokines, tumor necrosis factor-α (TNF-α) and interferon-γ inducible protein (IP-10), were significantly reduced in the presence of hUC-MSCs. Moreover, the secretion of anti-inflammatory cytokine, interleukin-10 (IL-10), was significantly increased after cocultured with hUC-MSCs. Prostaglandins E2 (PGE2), secreted by hUC-MSCs, is one of the crucial immunomodulatory factors and could be inhibited in the presence of COX2 inhibitor, NS-398. PGE2 inhibition suppressed hUC-MSCs immunomodulatory capability, which was restored after addition of synthetic PGE2, establishing the minimum amount of PGE2 required for immunomodulation. In conclusion, our data suggested that PGE2 is a crucial potency marker involved in the therapeutic activity of hUC-MSCs through macrophages immune response modulation and cytokines regulation. This study provides the model for the development of a surrogate quantitative potency assay of immunomodulation in stem cells production.
Subject(s)
Brain Ischemia/therapy , Dinoprostone/metabolism , Mesenchymal Stem Cell Transplantation/methods , Animals , Brain Ischemia/metabolism , Cell Differentiation/immunology , Coculture Techniques/methods , Cytokines/metabolism , Dinoprostone/immunology , Female , Fetal Blood/metabolism , Human Embryonic Stem Cells/metabolism , Humans , Immunity/drug effects , Immunomodulation/immunology , Macrophages/drug effects , Macrophages/metabolism , Male , Mesenchymal Stem Cells/metabolism , Mesenchymal Stem Cells/physiology , Microglia/metabolism , Prostaglandins E/immunology , Prostaglandins E/metabolism , Rats , Rats, Sprague-Dawley , Tumor Necrosis Factor-alpha/metabolism , Umbilical Cord/cytologyABSTRACT
OBJECTIVE: Previous study has demonstrated that EphA2 is a biomarker of mesenchymal stem cells (MSCs) from human placenta or umbilical cord and is able to distinguish MSCs from fibroblasts. In this study, we further examine the potential efficacy of EphA2+ human umbilical cord-derived MSCs (hUC-MSCs). MATERIALS AND METHODS: MSCs specific markers, EphA2 and CD146 expression on the surface of hUC-MSCs were determined by flow cytometry analysis. Quantitative real time polymerase chain reaction was used to examine pro-fibrotic gene expression of TGF-ß1-stimulated lung fibroblast (MRC-5 cells). On the other hand, ELISA was used to analyze the content of pro-inflammatory cytokines (TNF-É; and IP-10) in the LPS-activated macrophages culture supernatant. RESULTS: The pro-fibrotic gene (TGF-ß1, CTGF, fibronectin, collagen I and TIMP-1) expression in TGF-ß1-activated MRC-5 cells and the pro-inflammatory cytokines (TNF-É and IP-10) in the LPS-activated macrophages culture supernatant were both attenuated when in present of EphA2+ hUC-MSCs. Moreover, once EphA2+ hUC-MSCs treated with prostaglandin E2 specific inhibitor NS-398, both anti-fibrotic and anti-inflammatory effects of EphA2+ hUC-MSCs were abolished. CONCLUSION: EphA2+ hUC-MSCs possess immunomodulatory and anti-fibrotic properties, and PGE2 plays an important role in these activities. This implies that EphA2+ hUC-MSCs have potentially effectiveness for treatment of acute inflammatory and chronic fibrotic lung diseases.
