P-309 Injectable “homing-like” bioactive short-fibers for endometrial repair and efficient live births
Authors: Cao Y , Qi J , Wang J , Cui W , Sun Y 
Published: July 2024

Abstract

Study question
To develop effective therapeutic interventions to promote endometrial growth and facilitate the restoration of the damaged endometrium of rats with intrauterine adhesion (IUA).

Summary answer
We have developed injectable “homing-like” bioactive decellularized extracellular matrix short-fibers which can achieve efficient endometrial repair and live births of rats with IUA.

What is known already
The prevalence of infertility caused by endometrial defects has been steadily increasing, posing a significant challenge to women’s reproductive health. Various factors, such as infection and intrauterine surgery, can lead to damage to the basal layer of the endometrium, which hinders functional endometrial repair and results in the pathological development of IUA. However, there is currently no effective clinical treatment strategy for IUA. Therefore, it is imperative to develop effective therapeutic interventions to promote endometrial growth and receptivity, ameliorate endometrial fibrosis, and facilitate the restoration of the damaged endometrium that ultimately reverses the poor pregnancy outcomes of patients with IUA.

Study design, size, duration
We have developed an innovative method for creating injectable acellular extracellular matrix short fibers (DEFs) from porcine skin. We investigated the effects of DEFs by in vitro and in vivo experiments over a period of two years.

Participants/materials, setting, methods
In vitro, we investigated the pro-proliferative, anti-fibrosis and angiogenesis effects of DEFs in human primary endometrial stromal cells (HESCs) and human umbilical vein endothelial cells (HUVECs). In vivo, we constructed a rat IUA model to investigate the promotion of endometrial repair and fertility remodeling by DFEs.

Main results and the role of chance
The DEFs can effectively attract endometrial cells, enabling cell adhesion, spreading, and proliferation on their surface. DEFs are rich in bioactive growth factors, which creates a nourishing microenvironment for endometrial recovery while attracting and recruiting endogenous endometrial cells for in situ regeneration. Initially, DEFs formed stable bonds with the surface of endometrial cells via electrostatic interactions after injection into the uterine cavity, which acted as a physical barrier to prevent intrauterine adhesions. Subsequently, DEFs effectively facilitated the proliferation and angiogenesis of HESCs and HUVECs, and inhibited fibrosis of pretreated HESCs. Next, DEFs could decrease endometrial collagen deposition and promote endometrial repair and endometrial angiogenesis by releasing growth factors. Therefore, bioactive DEFs could efficiently improve endometrial receptivity, promote endometrial repair, and achieve efficient live births in endometrium-injured rats.

Limitations, reasons for caution
The composition of DEFs is complex. The mechanism by which DEFs promotes endometrial repair remains unclear. In our future endeavors, our primary aim is to conduct a proteomic analysis of the DEFs to pinpoint the vital proteins responsible for their ability to induce tissue growth.

Wider implications of the findings
The DEFs can achieve efficient live births and the preparation method is suitable for mass production. In addition, the injectability of DEFs can achieve non-invasive intrauterine injection, which can reduce the risk of endometrial re-injury. Therefore, the DEFs system provides a new promising clinical strategy for endometrial factor infertility.

Trial registration number
enter ‘not applicable