Efficacy of the natural cryoprotectant L-proline versus conventional cryoprotectants in human ovarian tissue cryopreservation and transplantation

doi:10.3969/j.issn.1006-7795.2026.04.006

Journal of Capital Medical University ›› 2026, Vol. 47 ›› Issue (4): 673-679.doi: 10.3969/j.issn.1006-7795.2026.04.006

Efficacy of the natural cryoprotectant L-proline versus conventional cryoprotectants in human ovarian tissue cryopreservation and transplantation

Liu Anming¹, Ruan Xiangyan^1*, Du Juan¹, Jiang Lingling¹, Li Yanqiu¹, Gu Muqing¹, Cheng Jiaojiao¹, Zhang Mingzhen¹, Wang Zecheng¹, Alfred O. Mueck^1,2

1.Department of Gynecological Endocrinology, Beijing Obstetrics and Gynecology Hospital, Capital Medical University. Beijing Maternal and Child Health Care Hospital, Beijing 100026, China ；2.Department of Women's Health, Research Centre for Women's Health and University Women's Hospital of Tuebingen, University Hospitals of Tuebingen, Tuebingen D-72076, Germany

Received:2026-04-09 Revised:2026-05-05 Online:2026-08-21 Published:2026-07-26
Supported by:
This study was supported by Beijing Municipal Administration of Hospitals’ Ascent Plan (DFL20181401), Beijing Municipal Health Commission, Demonstration Construction Project of Clinical Research Ward (BCRW202109), National Foreign Experts Individual Project, Establishment of Fertility Preservation and Consultation Center for Gynecological Endocrine Difficult Diseases (S20240236), National Foreign Experts Individual Project, Construction of National Female Ovarian Preservation and Anti-aging Promotion Project (S20240230).

Abstract

Abstract: Objective To evaluate the efficacy of the natural cryoprotectant L-proline (L-pro) in human ovarian tissue cryopreservation and transplantation, and to compare it with the conventional cryoprotectant dimethyl sulfoxide (DMSO).Methods Ovarian cortical tissues obtained from ten patients were cryopreserved using a slow-freezing protocol with either DMSO-based or L-pro-based cryoprotective solutions. After thawing, the tissues were xenotransplanted into ovariectomized female nude mice, while the control group underwent ovariectomy only. Twenty-one days after transplantation, grafts were retrieved for follicle counting, and serum levels of follicle-stimulating hormone (FSH), estradiol (E2), and anti-Müllerian hormone (AMH) were measured.Results The number of quiescent (primordial) follicles was significantly higher in the L-pro group than in the DMSO group (P=0.042), whereas no significant differences were observed in the number of growing follicles or total follicle counts between the two groups (all P> 0.05). Serum hormone levels in both experimental groups were significantly improved compared with the control group (all P<0.05), with no significant differences between the L-pro and DMSO groups.Conclusion L-pro, as a cryoprotectant, demonstrates comparable efficacy to DMSO in preserving follicular integrity and restoring endocrine function following ovarian tissue cryopreservation and xenotransplantation. These findings provide a novel perspective for optimizing cryoprotective agents in ovarian tissue preservation, although further studies are needed to elucidate the underlying mechanisms and long-term functional outcomes.

Key words: L-proline, natural cryoprotectant, ovarian tissue cryopreservation, xenotransplantation, fertility preservation, follicle

CLC Number:

Liu Anming, Ruan Xiangyan, Du Juan, Jiang Lingling, Li Yanqiu, Gu Muqing, Cheng Jiaojiao, Zhang Mingzhen, Wang Zecheng, Alfred O. Mueck, . Efficacy of the natural cryoprotectant L-proline versus conventional cryoprotectants in human ovarian tissue cryopreservation and transplantation[J]. Journal of Capital Medical University, 2026, 47(4): 673-679.

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Efficacy of the natural cryoprotectant L-proline versus conventional cryoprotectants in human ovarian tissue cryopreservation and transplantation

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