Therapeutical effect of local transplantation of bone marrow mesenchymal stem cells mixed with fibrin gel on rats with liver injury

Objective To investigate the method for the treatment of liver injury using bone marrow mesenchymal stem cells ( MSCs) .Methods The cryoprecipitate ( CP) rich in fibrinogen ( FIG) was extracted from rat plasma or human plasma using the freeze-thaw method and was used to make fibrin gel ( FG) . FIG, fibronectin ( Fn) , prothrombin time ( PT) , activated partial thromboplastin time ( APTT) , and factor Ⅷ activity were measured for the CP. The rat FG was mixed with rat MSCs to make FG-MSCs. The FG-MSCs were cultured in vitro, and MTT assay was used to measure the proliferation rate of MSCs. The components Ⅰ ( containing FIG and MSCs) and Ⅱ ( containing thrombin) of FG-MSCs were injected alternately into the same site of liver parenchyma tissue of the rats with liver injury to form FG-embedded MSCs, and a single dose of injection could be assigned to two or more sites. Such injection was repeated on days 21 and 28 after the first transplantation. On day 7 after the third injection, the body weight of rats was measured; the rats were sacrificed and plasma was collected to measure the levels of alanine aminotransferase ( ALT) , total bilirubin ( TBil) , and albumin ( Alb) ; the liver was weighed to calculate liver index [ ( mean liver weight/mean body weight) × 100%]. The t-test was used for comparison between two groups; a one-way analysis of variance was used for comparison between multiple groups, and the least significant difference t-test was used for further comparison between two groups. Results The CP of human plasma had significantly higher concentrations of FIG, Fn, and factor Ⅷ than the former plasma ( t = 9. 669, 12. 317 and 9. 043, all P < 0. 01) , while there were no significant differences in PT and APTT ( both P > 0. 05) . After in vitro culture for 4 days, FG-MSCs had a slightly higher proliferation rate than MSCs ( P > 0. 05) . After the injection of FG-MSCs or MSCs into the liver tissue of the rats with liver injury, there were significant reductions in the plasma levels of ALT and TBil ( both P < 0. 05) and a significant increase in the level of Alb ( P < 0. 05) . Conclusion The injection of FG-MSCs or MSCs into the liver parenchyma tissue can significantly improve the liver function of rats with liver injury, and FG-MSCs can also prevent bleeding after injection.