Warren B. Nothnick

Immunomodulation of Rat Endometriotic Implant Growth and Protein Production

PROBLEM: The immune system has been implicated in the pathophysiology of endometriosis. To determine if modulation of the immune system influences endometriotic implant growth and protein production, the following experiment was conducted.

Detection of a unique 32-kd protein in the peritoneal fluid of women with endometriosis * †

OBJECTIVE To test the hypothesis that endometriotic tissue secretes endometriotic-specific proteins into the peritoneal fluid (PF) of women with endometriosis. DESIGN A prospective design was utilized in this study. SETTING Tertiary care, university-based center and reproductive endocrinology laboratory. PARTICIPANTS Women of reproductive age who were infertile with endometriosis (n = 19), as well as without endometriosis (n = 7), and fertile women undergoing tubal ligation (n = 6). INTERVENTIONS Collection of PF fluid via laparoscopy. MAIN OUTCOME MEASURES Peritoneal fluid proteins were isolated and assessed by two-dimensional polyacrylamide gel electrophoresis. RESULTS Two-dimensional electrophoresis of PF proteins isolated a group of proteins (M(r) = 32 to 40 kd, pI = 4.5 to 5.2) in all PF samples that was similar to the rat endometriotic implant-specific protein, Endo-1. This group of proteins consisted of 5 to 12 individual proteins with endometriosis PF containing a significantly higher number of proteins (median = 11) compared with either PF from infertile women without endometriosis (median = 8) or from women undergoing tubal ligation (median = 7). In addition, one protein (M(r) = 32 kd, pI = 5.8), termed EPF-32, was detected predominantly (18 of 19 samples analyzed) in PF from women with endometriosis. This protein was also detected in PF from infertile women without endometriosis (2 of 7 samples) but not in the PF of fertile women undergoing tubal ligation (0 of 6 samples). The appearance of this protein was not associated with the severity of endometriosis. CONCLUSION It is concluded from this study that PF from women with endometriosis predominantly contains a 32-kd protein (EPF-32) compared with the PF of women without the disease. The role of EPF-32 in the pathophysiology of endometriosis is not established but this protein may function as a diagnostic marker for endometriosis.

Mifepristone and ovarian function.

In summary, RU 486 has been a powerful instrument in delineating progesterone action on the ovary. However, early experiments using RU 486 must be interpreted with the understanding that systemic administration of the antiprogestin may have had extraovarian sites of action, such as at the hypothalamic-pituitary axis or at the adrenal, that in turn led to indirect ovarian responses. Treatment with progesterone, agonist, or antagonist at periods during which the ovary lacks progesterone receptors would further suggest extraovarian sites of action or nongenomic mechanisms of action. Furthermore, the dose of ligand or antagonist administered and the hormonal milieu at the time of administration may dictate the ovarian response (Espey L, personal communication). For example, low doses of exogenous progesterone may elicit a biologic response, whereas high doses are without effect or may inhibit the biologic effect observed at lower doses. Although RU 486 is classically described as an antiprogestin, agonist actions have been observed in addition to its the well documented antiglucocorticoid effects. All of these variables may contribute to the confounding observations of progesterone and RU 486 action on the ovary. Regardless of these caveats, experimental paradigms have demonstrated that RU 486, either indirectly or directly, regulates ovarian folliculogenesis, stimulates and/or inhibits steroidogenesis depending on the species and time of RU 486 administration, inhibits ovulation, and modulates luteal function. These findings supports a progesterone-dependent mechanism in these varied aspects of ovarian function.