Human Fetal Testicular Tissue Xenotransplantation: A Platform to Study the Effect of Gonadotropins on Human Germ Cell Development In Utero.

PURPOSE: We examined the effects of long-term hCG stimulation on germ cell maturation, and Sertoli and Leydig cell function in a xenotransplantation model of the human fetal testis. MATERIALS AND METHODS: A total of 20 human fetal testes were ectopically xenografted on 20 castrated NCr male nude mice. Grafts were collected for analysis 24 weeks later. Mice were treated with saline as the control or with hCG beginning 4 weeks after the grafts were transplanted. RESULTS: Of the grafts 65% survived at 24 weeks. In contrast to untreated pregrafted samples, hCG stimulated xenografts showed significantly increased density of seminiferous tubule formation with Sertoli cell migration to the basement membrane. Germ cell proliferation and differentiation from gonocytes (M2A(+)) to prespermatogonia (MAGE-4A(+)) were observed in graft samples recovered from the hCG and nonhCG treated groups at 24 weeks of treatment. Leydig cells in hCG treated grafts produced significantly more testosterone than nonhCG treated grafts. Although further studies are required to investigate the potential for further differentiation and maturation of xenografted human fetal testes, normal in utero testicular development was reproduced under long-term hCG stimulation. CONCLUSIONS: This model represents a means to study long-term effects of gonadotoxins or hormonal stimulation on the maturation of human fetal testes.

The incidence and effect of bacteriospermia and elevated seminal leukocytes on semen parameters.

OBJECTIVE: To determine the incidence of bacteriospermia and elevated seminal leukocytes (ESL) in a subfertile male population and correlate these results with semen parameters. DESIGN: Retrospective cohort study. SETTING: Canadian tertiary-level male infertility clinic and university-affiliated andrology and microbiology laboratories. PATIENT(S): Four thousand nine hundred thirty-five nonazoospermic subfertile men. INTERVENTION(S): Analysis and concurrent culture of 7,852 semen samples. MAIN OUTCOME MEASURE(S): Incidence of bacteriospermia and ESL and comparison of semen parameters between these groups. RESULT(S): The rate of bacteriospermia was 15% (22 species), and the rate of ESL was 19%, with no statistical correlation between these groups. Bacteriospermic patients (without ESL) had a statistically significant deterioration in DNA fragmentation index (DFI) only, compared with patients without bacteriospermia and ESL (24.1 vs. 21.8%). ESL alone was associated with a statistically significant deterioration in sperm concentration (20.6 vs. 55.3 × 10(6)/mL), motility (21.8 vs. 26.9%), normal morphology (12.3 vs. 17.4%), and DFI (26.5 vs. 21.8%), with no additional deterioration identified with bacteriospermia. CONCLUSION(S): Bacteriospermia and ESL were prevalent, but not statistically associated, in subfertile men. Bacteriospermia alone was associated with an increase in DFI only, but the presence of ESL was the dominant factor associated with deterioration in semen parameters.