Successful heterotransplantation of human endometrium in SCID mice

Objective: To establish an experimental system useful for long-term evaluation of human endometrial tissue by its heterotransplantation to SCID mice. Methods: Human endometrium was transplanted subcutaneously into SCID mice, nude mice, or nude mice given anti-asialo GM₁ antibody, a natural killer activity suppressor. The transplant was observed by ultrasonography for up to 10 weeks and then morphologically. To assess the drug susceptibility of the transplant, danazol (10–100 mg/kg/day orally), buserelin (0.01 mg/kg/day subcutaneously), or estradiol (0.5 mg/kg/day intraperitoneally) was administered to the host mice for up to 10 weeks after the transplantation. Multiple-comparison procedures were used for statistical evaluation. Results: The heterotransplant was accepted 100% in SCID mice and natural killer activity-suppressed nude mice, but was significantly inferior (40%) in nude mice at 10 weeks after the transplantation. The transplant size was volumetrically measurable noninvasively by ultrasonography. Using this SCID mouse model, we could evaluate drug effects on the transplanted endometrium. Conclusion: This system in SCID mice may be useful for evaluating drug actions on human endometrium and endometriotic tissues.