OBJECTIVETo study the immunocharacteristics of bone marrow mesenchymal stem cell (MSC) and provide experimental evidence for the potential therapeutic application.

METHODSMSCs were isolated from rat bone marrow and confirmed by immunophenotype, and the growth dynamic and cell cycle were analyzed. MSCs were cultured with or without 200 U/ml interferon gamma (IFNg) , the expression of PDL-1, CD54, CD40, CD80, CD86, MHC-I, and MHC-II was detected by flow cytometry. MSCs were used as regulatory cells in mixed lymphocyte reaction (MLR), the PDL-1 and CD54 molecules on MSCs were blocked to explore their roles in MLR. The IFN, IL-2, IL-4 and IL-10 molecules in culture supernatant were quantified by ELISA. The homing of MSCs to liver and induction of microchimerism were analyzed after MSCs transplantation.

RESULTSThe purity of MSCs was high. The growth curve showed that the first two days were the lag phase; the third, fourth, fifth days were the log phase; the sixth and seventh days were the stationary phase. Flow cytometry indicated that 76.0%+/-2.0% of the MSCs were in G1/G0 phase, 13.0%+/-2.0% in S phase, 10.0%+/-1.7% in G2 and M phase. IFNg treatment led to up-regulation of CD54, PDL-1, MHC-I and MHC-II, however, CD40, CD80 and CD86 were not expressed on MSCs even after IFNg treatment. MSCs inhibited MLR, IFNg treatment enhanced the inhibitory effect of MSCs on MLR. Blocking of PDL-1 or CD54 on MSCs partially alleviated the inhibition effect. There were high levels of IFNg and IL-10, and low level of IL-4 in the culture supernatant of MLR, however, IL-2 was not detected. MSCs can home to the liver and induce formation of microchimerism after transplantation.

CONCLUSIONIFNg treatment enhances the inhibitory effect of MSCs on MLR, PDL-1 and CD54 are key molecules mediating this inhibitory effect. MSC can home to the liver and induce formation of microchimerism after transplantation.

Animals ; B7-1 Antigen ; immunology ; metabolism ; Bone Marrow Cells ; drug effects ; immunology ; metabolism ; Cell Proliferation ; Cells, Cultured ; Intercellular Adhesion Molecule-1 ; immunology ; metabolism ; Interferon-gamma ; administration & dosage ; pharmacology ; Lymphocyte Activation ; Lymphocyte Culture Test, Mixed ; Mesenchymal Stem Cell Transplantation ; Mesenchymal Stromal Cells ; drug effects ; immunology ; metabolism ; Rats ; T-Lymphocytes ; drug effects ; immunology ; metabolism

Objective To study the clinical and experimental efficacy of end-to-side gastro jejunostomy with circular stapler after distal subtotal gastrectomy.Methods Twelve Beagle dogs were randomly divided into group A and B. End-to-side gastroduodenostomy was finished with circular staplers or hand-sewn after gastrectomy. Side-to-side gastroduodenostomy was done in the second operation after three months.Healing and diameter of end-to-side gastroduodenostomy in Beagle'S were observed dogs.Perimeter of side-to-side gastroduodenostomy and duodenum adjacent to anastomosis were measured. One hundred and forty-five patients suffered from stomach cancer were randomly divided into group A and B.Group A had 71 cases and Group B 74 cases.End-to-side gastrojejunostomy was finished with circular stapler or hand-sewn after distal subtotal gastrectomy.Leakage and stricture of anastomosis were observed after operation.Size of anastomosis and track of Barium fluid and gastric residual Barium fluids two hours later were observed one year after operation.Results All operations in 12 dogs were successful.Healing of anastomoses and triangles at small curvature were satisfied three months after operation.Diameters of end-to-side gastroduodenostomy in group A and B were (1.18±0.13)am and(1.20±0.09)cm respectively，which were not significantly different between the two groups(t=-0.255，P=0.804).Circumferences of side-to-side gastroduodenostomy and duodenum adjacent to anastomosis were(6.46±0.06)cm and(7.26±0.12)cm respectively.All operations in 106 cases were successful and no complications of leakage and stricture of anastomosis occurred.Thin Barium fluid passed over anastomosis quickly under X-ray after one year.There was a little Barium fluid in the residual stomach in two hours later. Conclusion End-to-side gastrojejunostomy with circular stapler after distal subtotal gastrectomy is feasible. Anastomosis at the original position of residual stomach ensures adequate remove of stomach and prevents from trauma of spleen and vessel around spleen.

Objective To study the clinical and experimental efficacy of end-to-side gastro jejunostomy with circular stapler after distal subtotal gastrectomy.Methods Twelve Beagle dogs were randomly divided into group A and B. End-to-side gastroduodenostomy was finished with circular staplers or hand-sewn after gastrectomy. Side-to-side gastroduodenostomy was done in the second operation after three months.Healing and diameter of end-to-side gastroduodenostomy in Beagle'S were observed dogs.Perimeter of side-to-side gastroduodenostomy and duodenum adjacent to anastomosis were measured. One hundred and forty-five patients suffered from stomach cancer were randomly divided into group A and B.Group A had 71 cases and Group B 74 cases.End-to-side gastrojejunostomy was finished with circular stapler or hand-sewn after distal subtotal gastrectomy.Leakage and stricture of anastomosis were observed after operation.Size of anastomosis and track of Barium fluid and gastric residual Barium fluids two hours later were observed one year after operation.Results All operations in 12 dogs were successful.Healing of anastomoses and triangles at small curvature were satisfied three months after operation.Diameters of end-to-side gastroduodenostomy in group A and B were (1.18±0.13)am and(1.20±0.09)cm respectively，which were not significantly different between the two groups(t=-0.255，P=0.804).Circumferences of side-to-side gastroduodenostomy and duodenum adjacent to anastomosis were(6.46±0.06)cm and(7.26±0.12)cm respectively.All operations in 106 cases were successful and no complications of leakage and stricture of anastomosis occurred.Thin Barium fluid passed over anastomosis quickly under X-ray after one year.There was a little Barium fluid in the residual stomach in two hours later. Conclusion End-to-side gastrojejunostomy with circular stapler after distal subtotal gastrectomy is feasible. Anastomosis at the original position of residual stomach ensures adequate remove of stomach and prevents from trauma of spleen and vessel around spleen.