Human endometriotic xenografts in immunodeficient RAG-2/gamma(c)KO mice.

OBJECTIVE: The purpose of this study was to create a novel animal model for studies of endometriosis. STUDY
DESIGN: To facilitate the study of the transplantation of endometriosis into immunodeficient RAG-2/gamma(c)KO mice, endometriosis biopsy specimens were collected from 19 women by laparoscopic surgery and grafted subcutaneously into the mice, which were treated subsequently with estradiol and progesterone to create 28-day artificial cycles. The grafts were collected during the first, second, and fourth cycles and were evaluated histologically for evidence of bleeding and immunocytochemically for estrogen receptor and progesterone receptor.
RESULTS: Biopsy specimens that contained endometrium-like glands were well accepted (>90% success). These grafts maintained glandular morphologic condition, estrogen receptor, and progesterone receptor; bled after progesterone withdrawal; and formed chocolate cysts. However, biopsy specimens that lacked glands or that consisted of peritoneal adhesions and stroma were accepted poorly <5% success) and failed to show evidence of estrogen receptor, progesterone receptor, or cyclic bleeding.
CONCLUSION: Human endometriosis transplanted into RAG-2/gamma(c)KO mice can provide a model for endometriotic bleeding.