ABSTRACT
This study is to investigate the protective effects of the SB203580 against radiation induced mortality and intestinal injury of mice. A total of 67 male C57BL/6 mice (20.0-22.0 g) were matched according to body weight and randomly assigned to one of three groups: control, total body irradiation exposure (IR, 7.2 Gy) only, and IR (7.2 Gy) + SB203580 (15 mg x kg(-1)). 30 days survival rate was observed in the experiment. In intestinal injury experiment, the expression levels of caspase-3, Ki67, p53 and p-p38 were assayed in the mice intestine crypts. The results showed that the 30 days survival rate was 100% (control), 0 (IR) and 40% (IR+ SB203580), separately. Compared to the IR groups, the positive cells of caspase-3, p53 and p-p38 in crypt cells decreased 33.00%, 21.78% and 34.63%, respectively. The rate of positive cells of Ki67 increased 37.96%. Significant difference was found between all of them (P < 0.01). SB203580 potently protected against radiation-induced lethal and intestinal injury in mice, and it may be a potential radio protector.
ABSTRACT
BACKGROUND:Bone marrow mesenchymal stem cells have low immunogenicity and immunomodulatory effect,but there are seldom reports concerning the immunomodulatory effect of Wharton's jelly-derived mesenchymal stem cells of human umbilical cord and its mechanims.OBJECTIVE:To investigate the immunomodulatory effects and mechanisms of Wharton's jelly-derived mesenchymal stem cells of human umbilical cord on varient peripheral blood T lymphocytes.METHODS:Mesenchymal stem cells were isolateded from Wharton's jelly of human umbilical cord by tissue culture.T lymphocytes from human peripheral blood were stimulated by phytohemagglutinin and co-cultured with umbilical cord Wharton's jelly-derived mesenchymal stem cells and umbilical cord Wharton's jelly-derived mesenchymal stem cells supernatant respectively to measure A value following 72 hours of coculture using multifunctional microplate reader.Expression of cytokines including transforming growth factor-beta 1(TGF-β1)and interferon-y(IFN-γ)was evaluated by enzyme-labeled immunosorbent assay.RESULTS AND CONCLUSION:Wharton's jelly-derived mesenchymal stem cells could inhibite the proliferation of T lymphocytes induced by phytohemagglutinin.The proliferation inhibition rate was 56%(P＜0.01).Wharton's jelly-derived mesenchymal stem cells supernatant also had inhibitory effects on proliferation of T lymphocytes induced by phytohemagglutinin,in a dose-dependent fashion.The proliferation inhibition rates were 8.3% and 27% respectively in the 50% Wharton's jelly-derived mesenchymal stem cells supernatant and 100% Wharton's jelly-derived mesenchymal stem cells supematant groups(P＜0.05).Wharton's jelly-derived mesenchymal stem cells significantly decreased γ-interferon secrted from T-lymphocytes(P＜0.05).The secretion of TGF-β1 was lower in the coculture of Wharton's jelly-derived mesenchymal stem cells and T lymphocytes group than Wharton's jelly-derived mesenchymal stem cells alone group(P＜0.05).These indicated that Wharton's jelly-derived mesenchymal stem cells and Wharton's jelly-derived mesenchymal stem cells supernatant have inhibitory effects on proliferation of T lymphocytes induced by phytohemagglutinin.The mechanims may be associated with cell contant and inhibition of v-interferon secrted from T-lymphocytes.
ABSTRACT
BACKGROUND:Human mesenchymal stem cells derived from Wharton's jelly(WJCs)display the characteristics of MSCs as defined by the International Society for Cellular Therapy.They can be differentiated into bone,cartilage,adipose,muscle,and neural cells.They can also support the expansion of other stem cells,be weli-tolerated by the immune system,and have the ability to home to tumors.OBJECTIVE:To investigate biological changes of WJCs and brain tumor stem cells(BTSCs)co-cultured in vitro.METHODS:WJCs cultured by situ cultivation and BTSCs used enzyme digestion way respectively,and gathering the 3rd passage of WJCs though subculturing as well as BTSCs.Two kinds of cells co-cultured in 24-well plates in serum-free medium (SFM)without any growth factor.3 and 7 days after co-cultured respectively,CD133 expression of suspension cells in the 24-well plates were identified by flow cytometry,and immunofluorescence was performed for Nestin and glial fibrillary acidic protein (GFAP)expression of adherent cells.Co-culture supernatant(CCS)re-suspended 3~(rd) passage of BTSCs and cultured into 96-well plates at day 3,which were used to determine the difference in cell growth curve in both groups using a microplate reader.RESULTS AND CONCLUSION:With the cocultivation days increasing,the phenomenon that tumor sphere cells began to be decomposed,adherent and differentiated observed by an inverted microscope.BTSCs in the co-cultured group expressed GFAP and Nestin when adherent and differentiated.The higher degree of malignant brain tumor tissue used in culturing BTSCs was,the higher expression of CD133 in BTSCs was.CD 133~+ in BTSCs declined when co-cultured with WJCs.Growth curve of brain tumor stem cells cultured in CCS compared with in SFM at day 3,which indicates that the proliferation of BTSCs inhibited obviously.Results indicated that CD 133~+ expression and proliferative capacity of BTSCs went down and BTSCs underwent differentiation during the co-culture in vitro.