Collagen Scaffold with Human Umbilical Cord Mesenchymal Stem Cells Remarkably Improves Intrauterine Adhesions in a Rat Model

<b><i>Background:</i></b> Intrauterine adhesion (IUA) is the second leading cause of secondary infertility in women. Research has shown that stem cells can promote endometrial regeneration and that biomaterials are also helpful in tissue regeneration. Therefore, we compared the efficacy of a collagen scaffold combined with either human umbilical cord mesenchymal stem cells (hUCMSC) or estrogen for the treatment of IUA. <b><i>Methods:</i></b> The IUA-induced rats were injected with hUCMSCs or estrogen, and with a collagen scaffold. The endometrial glands and amount of fibrosis were assessed using hematoxylin and eosin and Masson staining. The extent of fibrosis and levels of regeneration-related cytokines were examined by real-time quantitative PCR, and the expression levels of the estrogen receptor, KI67 and cytokeratin were analyzed using an immunochemistry assay. In addition, human nuclear antigen (HuNu) and vimentin were examined by immunofluorescence microscopy. <b><i>Results:</i></b> The collagen scaffold administered with hUCMSCs markedly increased the number of endometrial glands and reduced the area of fibrosis compared with either the collagen scaffold or hUCMSCs alone. In addition, the collagen scaffold with hUCMSCs significantly regulated the expression levels of fibrosis, estrogen, and differentiation-related genes relative to the collagen scaffold or hUCMSCs alone. Furthermore, the hUCMSCs alone or in combination with the collagen scaffold increased the expression of HuNu and vimentin in the IUA-induced rat model. In addition, protein levels of the p-transcriptional co-activator with PDZ-binding motif, stromal cell-derived factor-1, and C-X-C chemokine receptor type 4 were upregulated in the group that received the collagen scaffold in combination with ­hUCMSCs. <b><i>Conclusion:</i></b> Our results suggest that the combination of the collagen scaffold with hUCMSCs may be an alternative approach for treating IUA.