Abstract: 329

TRANSPLANTATION OF RABBIT GERM CELLS INTO MOUSE TESTES.

Ina Dobrinski^{1 *}, Mary R. Avarbock¹ , Ralph L. Brinster^{1 *}
School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA ¹

Spermatogonial stem cells of a fertile mouse transplanted into the seminiferous tubules of an infertile mouse develop donor-derived spermatogenesis and transmit the donor haplotype to progeny of the recipient mouse. When testis cells from rats or hamsters were transplanted to the testes of immunodeficient mice, complete donor spermatogenesis occurred in the recipient mouse testes albeit with lower efficiency in the hamster. The objective of this study was to investigate the effect of increasing phylogenetic distance between donor and recipient on the outcome of spermatogonial transplantation. Testis cells were collected from donor rabbits and transplanted into testes of immunodeficient recipient mice (n=25) in which endogenous spermatogenesis had been destroyed. Rabbit testis cells were also frozen and stored in liquid nitrogen before transplantation into mice (n=11). Recipient testes were analyzed from 1 to >12 months after transplantation for the presence of rabbit germ cells by whole mount immunocytochemistry using a donor-specific polyclonal antibody. Rabbit germ cells were present in all recipient testes analyzed. They formed chains and networks of round cells connected by intercellular bridges closely resembling early stages of colonization by proliferating mouse spermatogonia, but later stages of donor spermatogenesis were not observed. These results indicate that fresh and cryopreserved rabbit germ cells could colonize the mouse testis but did not differentiate beyond the stage of spermatogonial expansion. This might be due to incompatibilities between rabbit germ cells and mouse Sertoli cells or deficiencies in the microenvironment of the mouse seminiferous tubules. (NICHD 36504, USDA 95-37205-2353, Commonwealth of Pennsylvania, and the Kleberg Foundation)

    This abstract is being presented on Monday, August 2 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.