Objective: To evaluate the concentration and distribution pattern of interleukin-6-producing cells in ectopic and eutopic endometrium.
Design: Collection of both tissues at the proliferative cycle phase.
Setting: A university endocrinology and laparoscopy program.
Patient(s): Twelve samples from six women were obtained at operative laparoscopy in the proliferative phase of each woman's cycle.
Intervention(s): Paired sampling of ectopic (n = 6) and eutopic endometrium (n = 6).
Main outcome measure(s): Concentration of IL-6 messenger RNA (mRNA) was measured by real-time RT-PCR, and its distribution was determined by in situ RT-PCR.
Result(s): In vitro RT-PCR analysis showed distinct bands at 234 bp and 115 bp for IL-6 mRNA in eutopic and ectopic endometrium and in placenta as positive control. Real-time RT-PCR indicated significantly higher expression of IL-6 in tissue with endometriosis than in tissue without. In all 12 samples subjected to in situ RT-PCR, positive signals of IL-6 mRNA were observed in cytoplasm of epithelial and stroma cells of ectopic and eutopic endometrium tissue.
Conclusion(s): The significant IL-6 mRNA increase in endometriosis compared with in eutopic endometrium may play a role in the development of endometriosis and may provide new directions for endometriosis research.