Back muscle as a promising site for ovarian tissue transplantation, an animal model.

ABSTRACT

BACKGROUND: The aim of this study was to evaluate the optimal transplantation site for ovarian tissue fragments in murine hosts. We compared the transplantation to the back muscle (B) versus the kidney capsule (K) in a mouse allograft model. METHODS: Hemi-ovaries from 12-day-old mice were allografted into B and K of bilaterally ovariectomized same strain recipients which had undergone gonadotrophin stimulation (n = 15). Graft survival after 27 days, angiogenesis and follicle development were scored and compared to age-matched control ovaries (38-day old, n = 5). The ability of oocytes to be fertilized was studied after IVF, ICSI and embryos were transferred to recipient mothers. Anti-mouse CD 31+ antibody was used to evaluate neo-vascularization in grafts. RESULTS: Primordial follicle survival was higher (P < 0.01) and vascular support was better (P < 0.01) in B- than in K-grafts. From 34 oocytes retrieved from B-grafts (15 metaphase I, of which 14 matured in vitro, and 19 collected at metaphase II), 18 morulae were obtained. Transfer of 12 embryos obtained by ICSI led to three live offspring, and transfer of six IVF embryos to another recipient mother yielded four offspring, one of which was born dead and one showed placental anomalies. CONCLUSIONS: The back muscle is a promising site for ovarian allografts in mice. This is the first report of live offspring obtained after back muscle grafting using both IVF and ICSI.