Self-Assembled Peptide Hydrogels Loaded with Umbilical Cord-Derived Mesenchymal Stem Cells Repairing Injured Endometrium and Restoring Fertility.

Endometrial injury is a major cause of infertility and recurrent miscarriage. However, no clinically available methods currently exist to effectively repair the damaged endometrium. Mesenchymal stem cells (MSCs) have emerged as a promising therapeutic approach for promoting tissue regeneration, yet a biocompatible scaffold capable of delivering MSCs and supporting their growth is needed. Herein, the study reports a peptide hydrogel scaffold, self-assembled from a peptide IVK8-RGD consisting of an ionic complementary peptide sequence IEVEIRVK and a bioactive sequence RGD, to load umbilical cord-derived mesenchymal stem cells (UC-MSCs). This peptide forms a hydrogel under the physiological condition through self-assembly, and the peptide hydrogel exhibits injectability and adhesiveness to uterus, making it suitable for endometrial repair. Importantly, this hydrogel supports the adhesion and proliferation of UC-MSCs in a 3D environment. In vivo experiments using rats with endometrial injury have shown that treatment with IVK8-RGD hydrogel loaded with UC-MSCs effectively restores endometrial thickness, inhibits fibrosis, and facilitates angiogenesis through activating Raf/MEK/ERK pathway, leading to significantly improved fertility and live birth rate. These findings demonstrate the potential of the UC-MSCs-loaded hydrogel in repairing damaged endometrium and may address the unmet clinical needs of treating recurrent miscarriage and infertility induced by endometrial damage.