Therapeutic Potential of EO and HEO Complexes in Endometrial Regeneration and Vascularization: A Preclinical Study in Mice

To evaluate the therapeutic potential of EO complex and HEO complex in endometrial regeneration, we established an endometrial injury model in mice and examined the effects of intrauterine complex administration. Six to eight-week-old female SCID mice were subjected to laparotomy under anesthesia, exposing the left uterus. Ligations were placed at both the oviductal and cervical ends of the uterine horns. Subsequently, 95% ethanol was injected into the uterine cavity via the oviductal end, held for 15 seconds, and then flushed with PBS. EO complex and HEO complex, cultured for 2 days in eCHIP supplemented with estradiol, were collected. A volume of 75 μl of each cell complex was injected into the injured uterine cavity using a 1ml syringe. Control groups received either an equal volume of Matrigel or PBS, serving as the Matrigel-treated and natural repair groups, respectively. Three minutes post-injection, the ligatures were removed, the uterus was repositioned, and the abdomen was sutured. Uteri were harvested at 3 and 7 days post-surgery for histological and immunohistochemical analysis. Following a 14-day recovery period, mice were mated with ICR male mice of reproductive age to assess fertility.

To assess the in vivo vascularization capacity of EO complex and HEO complex, 30 μl of each complex was transplanted subcutaneously into the shoulder region of SCID female mice. After 14 days, a fluorescent dye was injected intravenously. Thirty minutes post-injection, the transplants were excised and visualized using confocal microscopy to assess neovascularization.