Characterization of immunoglobulins and cytokines in human cervical mucus:influence of exogenous and endogenous hormones

Mucosal immunity in the female reproductive tract is influenced by immunogl obulins (Igs), cytokines, and reproductive hormones. Previous studies of re productive-aged women demonstrated that IgA and IgG increases in cervical m ucus corresponded to elevated levels of IL-1 beta which occurred 1 day befo re the peak of endogenous estradiol production prior to ovulation. We sough t to determine the effect of exogenous hormones on reproductive tract immun ity in women on oral contraceptive pills (OCPs) and to compare the results with respect to naturally cycling women. Twelve women of reproductive age w ho had negative cervical cultures, a normal pap smear, and agreed to abstai n from sexual intercourse during the study initiated OCPs. Cervical mucus a nd vaginal washes were collected at six intervals (2-3 days apart) througho ut the treatment cycle. Fifteen naturally cycling women had similar samples collected prior to, during, and subsequent to ovulation. Cervical mucus sa mples were assayed for IgA, IgG, IL-1 beta, IL-6, and IL-10 by enzyme-linke d immunosorbent assay (ELISA). IgA, IgG and IL-1 beta levels in women on OC Ps paralleled increasing levels of norethindrone. Mean values of IEA increa sed from a low of 14.4+/-3.1 to 41.1+/-9.4 mg/dl and decreased significantl y after the cessation of the pills (P < 0.001). In naturally cycling women, the largest quantities of Igs were detected prior to ovulation. By compari son, mean values of IgA in the cervical mucus of women on OCPs (24.4 mg/dl) exceeded peak levels of IgA in the cervical mucus of naturally cycling wom en (14.6 mg/dl). IgA was the predominant Ig detected in cervical mucus of w omen on OCPs. Both immunoglobulins in each group exhibited changes relative to their hormonal status. The increased levels of IgA in the cervical mucu s of women on OCPs may explain the clinical observation of a lower incidenc e of sexually transmitted diseases. (C) 1999 Elsevier Science Ireland Ltd. All rights reserved.