ANTICHLAMYDIAL ACTIVITY OF VAGINAL SECRETION

OBJECTIVE: The purpose of this study was to investigate the possible a ntichlamydial activity of vaginal secretion and to partially character ize the inhibitory principle. STUDY DESIGN: Vaginal secretions obtaine d from 156 women attending a family planning or gynecologic outpatient clinic for contraceptive advice were studied for the influence on the inclusion formation of Chlamydia trachomatis in cycloheximide-treated McCoy cell cultures. RESULTS: Vaginal secretions from 156 women inhib ited the inclusion formation of Chlamydia trachomatis. The inhibition was concentration dependent and the inhibitory principle had a molecul ar weight of <10,000 d. It was heat labile. It was not related to anti chlamydial antibodies in vaginal secretions. Only three (2%) of the wo men had a positive culture for Chlamydia trachomatis. Three had immuno globulin A and three had immunoglobulin G antichlamydial antibodies in vaginal secretions. Secretions or those with a vaginal pH of 3.5 to 4 .5 decreased the chlamydial inclusion count by 75% compared with contr ols. The corresponding percentage for those with a pH of 5.0 to 6.0 wa s 48% and for those with pH > 6 was 33%. Vaginal secretions of oral co ntraceptive users and nonusers did not differ in the capacity to decre ase the chlamydial inclusion count, p > 0.01. CONCLUSIONS: When vagina l secretions were added to McCoy cell cultures infected by Chlamydia t rachomatis, the chlamydia inclusion number decreased. There was a corr elation between pH of the vaginal secretion and the inhibitory princip le. Oral contraceptive use had no influence on the inhibition.