Transplantation Of Menstrual Blood-Derived Mesenchymal Stem Cells (Mbmscs) Promotes The Regeneration Of Mechanical Injuried Endometrium

Purpose: The ultimate cause of intrauterine adhesions (IUAs) is the substantial destruction of the endometrium, which makes the regeneration of endometrium difficult. The purpose of this study was to observe menstrual blood-derived mesenchymal stem cells (MbMSCs)'s effect on the endometrial regeneration with different methods of transplantation. We also studied whether MbMSCs transfected with the FGF2 gene can improve the regenerative effect. Methods: 75 female SD rats with endometrium removed were used as IUA models. These IUA models were divided into 5 groups: group A was the IUA control, group B received a scaffold transplant, group C received a scaffold+MbMSC transplant, group D received a scaffold+FGF2-MbMSC transplant, and group E received FGF2MbMSCs injected via the tail vein. After the intervention, 5 rats from each group were sacrificed on the 7th day and the 28th day respectively. The distribution of MbMSCs in endometrium was traced using enhanced green fluorescent protein. The endometrial morphology, number of endometrial glands, area of endometrial fibrosis and immunohistochemistry (IHC) of Ki67, VEGF, and CD31 were evaluated. In addition, the fertility of all groups was tested. Results: On the 7th day after transplantation, enhanced green fluorescent protein showed that there were more MbMSCs in the uterine cavity of group D than that of group E. The endometrial morphology of groups A and B was atrophic and thinned with a high proportion of fibrosis in the endometrium. The endometrium of groups C, D and E was thickened, contained more glands, exhibited reduced fibrosis, and had increased expression of Ki67, VEGF and CD31. The endometrial regenerative effect from high to low was D > C > E with significant differences between each two groups. The fertility test verified the regenerative effect. Conclusions: These results suggest that the injection of MbMSCs into the tail vein was an effective way to stimulate endometrial regeneration, but the effect was not so well as the intrauterine transplant of MbMSCs with scaffold. The FGF2-transfected MbMSCs exhibited enhanced regenerative effect.