[Placenta-derived mesenchymal stem cells with HLA-G positive expression induce Treg in vitro].

OBJECTIVE: To study placenta-derived mesenchymal stem cells with HLA-G (Human Leukocyte Antigen, HLA-G) positive expression induce Treg (regulatory T cell, Treg) in vitro. METHODS: placenta-derived mesenchymal stem cells were separated from neonatal placenta; PEGFP - N1 -HLA-G plasmid was transfected in placenta-derived mesenchymal stem cells by liposome transfection.The cells were divided into 3 groups including control group, PEGFP-N1 group and PEGFP-N1-HLA-G group, 5 complex walls in each group. Expression of HLA-G protein was detected by Western Blotting; after identification of cells, healthy human peripheral blood CD4+ T lymphocytes were cultured with placenta-derived mesenchymal stem cells with HLA-G positive expression, and the ratio of CD4+CD25+Foxp3+Treg in T lymphocytes was accounted. RESULTS: After transfection of PEGFP-N1-HLA-G, the placenta-derived mesenchymal stem cells can express HLA-G protein significantly, compared with the control group and PEGFP - N1 group (P<0.01). After HLA-G positive placenta-derived mesenchymal stem cells and CD4 + T lymphocytes were cultured for 24 h, the ratio of CD4+CD25+Foxp3+Treg in T lymphocytes was (16.41±0.94)%. After HLA - G positive placenta-derived mesenchymal stem cells and CD4+ T lymphocytes were cultured for 48 h, the ratio of CD4+CD25+Foxp3+Treg in T lymphocytes was (16.46±0.59)% significantly, compared with the control group and PEGFP - N1 group (P<0.01). CONCLUSIONS: Placenta-derived mesenchymal stem cells modified by HLA-G gene can effectively induce CD4+CD25+Foxp3+Treg in vitro.

Promotive Effects of Dcr3 Gene on the Occurrence and Progression of Gastric Cancer and its Mechanism.

BACKGROUND/AIMS: To observe the effects of DcR3 gene on the occurrence and progression of gastric cancer and explore its mechanism. METHODOLOGY: DcR3 mRNA expressions in both gastric normal tissue and gastric cancer tissue were detected with RT-PCR. Apoptosis index (AI) was determined with terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL). RESULTS: Positive rate of DcR3 mRNA expression was significantly higher in gastric cancer tissue than in gastric normal tissue (P < 0.01). The level of DcR3 mRNA expression was related to differentiation, lymphatic metastasis and TNM staging (P < 0.05). The level of DcR3 mRNA expression was inversely correlated with AI (P < 0.01). CONCLUSION: DcR3 plays an important role in the occurrence and progression of gastric cancer possibly through inhibiting gastric cancer cell apoptosis.