Role of interleukin-1 receptor type II in the pathogenesis of endometriosis.

OBJECTIVE: To determine the role of interleukin-1 receptor type II (IL-1RII) in the pathogenesis of endometriosis.

DESIGN: Cultures of endometrial cells exposed to soluble IL-1RII or the recombinant adenovirus of IL-1RII (rAd-RII).

SETTING: Gynecology clinic and human reproduction research laboratory.

PATIENT(S): Women with endometriosis undergoing hysterectomy.

INTERVENTION(S): Cell culture media were collected 12 hours after addition of soluble IL-1RII or infection of rAd-RII.

MAIN OUTCOME MEASURE(S): The levels of IL-6 and IL-8 in the culture media were measured via enzyme-linked immunoabsorbent assay. Furthermore, proteins of the cells were collected for two-dimensional electrophoresis and the differential protein expression was identified by the matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry.

RESULT(S): Addition of soluble IL-1RII (2.0 microg/mL) significantly inhibited IL-1 beta-induced IL-6 and IL-8 secretion by endometrial cells in vitro. Infection of endometrial cells with rAd-RII significantly decreased IL-1 beta-induced IL-8 secretion, compared with the PBS and rAd-LacZ controls but had no significant effect on IL-6 secretion. Proteins of the infected cells were collected for two-dimensional electrophoresis, and intensities of 62 spots were significantly increased or decreased when compared with those in the PBS group. Thirty-four proteins were identified by MALDI-TOF mass spectrometry. The majority of the identified proteins are related to cellular metabolism and proliferation.

CONCLUSION(S): These results suggest that IL-1RII can neutralize IL-1 beta and counteract its effect on endometrial stromal cells, and may provide a new clinical strategy for the treatment of endometriosis.