Umbilical cord derived-mesenchymal stem cells affect the immune response of umbilical cord blood CD_(34)~+ cells

【Objective】To investigate whether the umbilical cord-derived mesenchymal stem cells (UC-MSCs) can affect the immune response of umbilical cord blood (UCB) CD34+ cells,affecting the secretion of immune regulatory cytokines effectively. 【Methods】MSCs were isolated from umbilical cord; the morphology of UC-MSCs were observed by microphotograph,surface markers were identified by flow cytometry; we added a different number of UC-MSCs into co-cultivation system of UCB CD34+ cells and peripheral blood mononuclear cells (PBMC),in addition,we mixed this three kinds of cells using Transwell,UBC CD34+ cells and PBMC were cultured in the upper separated from UC-MSCs,and cultivation of CD34+ cells and PBMC as negative group,supernatants were collected and detected of the IFN-γ and IL-10 level by ELISA.【Results】Flow cytometry showed that UC-MSCs did not express CD40,CD80,CD86 and major histocompatibility complex Ⅱ class molecules. It can inhibit IFN-γ secretion (19.30±0.78) vs (27.00±1.11),(P 0.05),promote IL-10 secretion (50.28±1.29) vs (31.68±3.08),(P 0.05) and had a dosedepended. Using Transwell,UC-MSCs have this immunomodulation too,but the effects decreased.【Conclusions】 UC-MSCs can inhibited the secretion of IFN-γ and promoted the secretion of IL-10 in the immune response of UCB CD34+ cells,and partly depended on the contacts between cells. Co-transplantation of UC-MSCs and UBC CD34+ could can serve as alternative of stem cells transplantation for ischemic cardiomyopathy.