Cryopreservation and xenotransplantation of human ovarian tissue: an ultrastructural study
Received 20 September 2006; received in revised form 23 March 2007; accepted 29 May 2007. published online 30 August 2007.
Objective
To analyze the ultrastructure of human ovarian follicles after cryopreservation and short-term xenografting.
Design
Prospective experimental study.
Setting
Academic gynecology and anatomy research units.
Patient(s)
Ovarian cortical biopsy specimens were obtained from 13 patients.
Intervention(s)
Each ovarian biopsy specimen was dissected into pieces of 1 mm3 and divided into three groups: [1] fresh tissue, [2] frozen-thawed tissue, and [3] frozen-thawed tissue xenografted onto the peritoneum of nude mice for 3 weeks.
Main Outcome Measure(s)
Follicular ultrastructure was assessed by light and transmission electron microscopy in [1] fresh, [2] frozen, and [3] frozen-grafted tissue.
Result(s)
Thirty-five ovarian follicles were analyzed by light and transmission electron microscopy. Twenty-five primordial and primary ovarian follicles were found. Most of them exhibited ultrastructurally well preserved features (fresh [N = 8/10], frozen [N = 7/10], and frozen-grafted [N = 4/5] tissue). Ten secondary follicles were present in xenografts. By transmission electron microscopy, all the healthy-looking secondary follicles (70%) were shown to contain intact oocytes, with features typical of earlier developmental stages, surrounded by several layers of follicular cells.
Conclusion(s)
The present study demonstrates, for the first time, that cryopreservation and xenotransplantation do not appear to greatly affect human primordial/primary follicle ultrastructure. Interestingly, in frozen-thawed xenografts, secondary human ovarian follicles presented a well preserved ultrastructure, but asynchrony between oocyte and granulosa cell development was detected. The possible causes for this asynchrony are discussed.
aDepartment of Anatomy, University of Rome “La Sapienza,” Rome, Italy
bDepartment of Gynecology, Université Catholique de Louvain, Brussels, Belgium
cDepartment of Experimental Medicine, University of L'Aquila, L'Aquila, Italy
Reprint requests: Jacques Donnez, M.D., Ph.D., Department of Gynecology, Université Catholique de Louvain, Cliniques Universitaires St. Luc, Avenue Hippocrate 10, 1200 Brussels, Belgium (FAX: 32-2-764-95-07).
Drs. Nottola and Camboni have contributed equally to this article.
Supported by grants from the Fonds National de la Recherche Scientifique (No. 7.4519.04 and No. 7.4547.06), the Fondation St. Luc, the Belgian Federation Against Cancer, Baron Albert Frère and Comte de Spoelberch, the Italian Ministry of Education, University and Research (PRIN funds 2001–2003 and university grants 2002–2004), and the Italian Ministry of Foreign Affairs: VII Executive Programme of Scientific Collaboration between Italy and the French-speaking Community of Belgium 2005–2006.
ABSTRACT