Impact of administering umbilical cord-derived mesenchymal stem cells to cynomolgus monkeys with endometriosis.

Purpose: This study aimed to explore whether umbilical cord-derived mesenchymal stem cells (UC-MSCs) could be used as a therapeutic resource for endometriosis.
Methods: Of seven cynomolgus monkeys with endometriosis, five were administered UC-MSCs (intervention group) and two were administered saline (control group). First, intravenous US-MSC treatment was administered for three months. Second, weekly intravenous US-MSC administration combined with monthly intraperitoneal US-MSC administration was conducted for 3 months. Finally, weekly intraperitoneal US-MSC administration was conducted for 3 months. The dose of UC-MSCs was set to 2 × 10 ⁶ cells/kg for all administration routes. Laparoscopic findings and serum cancer antigen 125 (CA125) levels were also evaluated. The Revised American Society for Reproductive Medicine classification was used for laparoscopic evaluation.
Results: Laparoscopic findings showed exacerbation of endometriosis after intraperitoneal UC-MSC administration, although no changes were observed in the control group. Intravenous UC-MSC administration decreased the level of CA125 in all monkeys; however, the difference was not significant. Intraperitoneal UC-MSC administration significantly exacerbated endometriosis compared with intravenous administration ( p  = 0.02).
Conclusions: This study revealed that intraperitoneal UC-MSC administration exacerbates endometriosis in a nonhuman primate model of the disease.
Competing Interests: Author T. Murakami is an Editorial Board member of Reproductive Medicine and Biology and a co‐author of this article. To remove bias, he was excluded from all editorial decision‐making related to the acceptance of this article for publication.
(© 2023 The Authors. Reproductive Medicine and Biology published by John Wiley & Sons Australia, Ltd on behalf of Japan Society for Reproductive Medicine.)