Anti-corpus luteum antibody: A novel serological marker for ovarian dysfunction in systemic lupus erythematosus?

Objective, To investigate the presence of autoantibodies directed to corpus luteum (CoL) in systemic lupus erythematosus (SLE) sera and its correlatio n with menstrual disturbances. Methods. We evaluated 87 female patients with SLE < 40 years old, and 23 wo men with normal menses as controls. Anti-corpus luteum antibody was detecte d by immunoblot technique, Results. Reactivity to a bovine CoL antigen was found in 22% of SLE sera. C haracterization of the target antigen revealed a 67 kDa glycoprotein highly enriched in corpus luteum, but nearly absent in total ovary extract. Simil arly, target antigen was also weakly detectable in tissues that produce or metabolize steroids, such as testis, adrenal cortex, and liver, and it was absent in adrenal medulla or HEp-2 cells. Anti-CoL antibody was easily dist inguished from other frequent reactivities of SLE sera, including anti-RNP, anti-Sm, anti-Ro/La, anti-dsDNA, or anticardiolipin. The observation of an ti-67 kDa reactivity to human CoL suggests a possible pathogenic role in go nadal dysfunction, Indeed, we observed an inverse association of anti-CoL a ntibody with the duration of hypergonadotropic amenorrhea. Supporting this hypothesis, in patients with normal or irregular menses, the presence of th is antibody was associated with elevated serum level of follicle stimulatin g hormone, an early and specific sign of ovarian lesion. Conclusion Anti-CoL antibody seems to be associated with early stages of ov arian dysfunction in SLE. Moreover, since similar association of antiovaria n antibodies has been observed in an experimental model of autoimmune oopho ritis, our findings raise the possibility of autoimmune ovarian lesion in p atients with SLE.