| Objective To investigate the effect and mechanisms of transplantation induced by infusion CTLA4Ig-BMSCs via the tail vein.To provide an new protocol and idea for inducing limb transplantation toleranceMethods1ã€With AdEasy vector system, the recombinant adenoviruses containing CTLA4—Ig gene was constructed and the viral titer was measured.BMSCs were infected with the recombinant adenoviruses and the expression of CTLA4-Ig was detected by RT--PCR.2. Build limb transplantation in rats were randomly divided into A, B, C, D, four groups.Group A:blank control group Group B:infusion AdCTLA4Ig via the tail vein.Group C:infusion BMSCs via the tail vein Group D:infusion CTLA4Ig-BMSCs via the tail vein。The survival of grafts and transplantation rats were observed after transplantation. The morphological changes of grafts were observed by hematoxylin. eosin staining; cytokines were quantified by ELISA.Results (1)The recombinant adenovirus containing CTLA4-Ig gene was constmcted successfully and its titer was1.0*109efu/ml. The recombinant virus AdCTLA4Ig prepared in this study efficiently infected BMSCs and the infected cells expressed recombinant protein CTLA4Ig。(2) The survival of grafts in group D was significant longer than that in group A, B and D respectively(p<0.05); The survival of group B and C were significantly prolonged compared with group A(p<0.05)and the survival of group B was not significantly different with group C(p>0.05).(3) On day7post—transplantation, hematoxylin—eosin staining of grafts. Blank control group shows severe infiltration of lymphocytes; group B and C shows moderate infiltration of lymphocytes; groupD shows mild infiltration of lymphocytes。Conclusion (1) Recombinant adenoviruses could be obtained quickly and simply by using AdEasy system。(2) Via the tail vein infusion CTLA4Ig-BMSCs can induce immune tolerance, and superior to the single infusion AdCTLA4-Ig and BMSCs group. |