Sex steroid hormones and antibodies to Candida albicans

The effect of changes in progesterone (P) and estradiol (E2) on titres of antibodies to Candida albicans was studied by measurement of these three parameters in the following endocrinologically diverse human groups: normal females, gonadal dysgenetics, users of a sequential oral contraceptive (Oracon) and normal males. In females, C. albicans titres (mean +/- s.e.m.) were significantly higher (P less than 0.05) in the luteal (74 +/- 14) than in the follicular phase (34 +/- 19) of the cycle, and there were similar significant increases in P and E2. In the gonadal dysgenetic group (n = 29), with E2 levels comparable with males, the antibody titres were also equivalent to those in normal males (40 +/- 0.5), but were significantly lower than those of normal females in the follicular phase (P less than 0.05). In contrast, Oracon users, with high blood progestin levels, had C. albicans titres (118 +/- 15) significantly higher (P less than 0.001) than those of control subjects during the follicular phase. A significant correlation (P less than 0.05) was observed between P and C. albicans titres (mainly IgA) in randomly selected samples (n = 112) from normal females during the follicular and luteal phases, and in two subjects from whom blood samples were drawn daily for the entire cycle. In the latter, an increase in E2 but not P in the late follicular phase was accompanied by a marked decrease in C. albicans titres. No changes were observed in total immunoglobulin levels or antibodies to SRBC or Herpes virus in response to the marked changes in hormones. These results indicate that the production of antibodies to C. albicans may be specifically influenced by sex steroid hormones, being enhanced by P and E2 at low levels but depressed by E2 at high levels.