Our data suggest that interleukin-10 and interferon-γ regulate C trachomatis-specific immune responses in humans and that genetic variation in the expression of their coding genes explains interindividual variation in host immune responses to C trachomatis infection.
We found that the IL-10 -1082 AA genotype and the TNF-alpha -308 A allele increased the risk of severe tubal damage in women with infertility associated with C. trachomatis (odds ratio [OR], 7.3 [95% confidence interval {CI}, 1.3-42] and 4.0 [95% CI, 1.0-16], respectively), suggesting that differences in these genes contribute to the wide spectrum of disease manifestations.
These findings provide a plausible functional explanation for the observed genetic association, and support the hypothesis that an excessive IL10 response to C. trachomatis infection is a risk factor for scarring and blindness.
In a multivariate analysis, elevated levels of IFN-gamma, IL-10, and IL-12 were significantly (p < 0.05) associated with several variables, including current C. trachomatis infection, recent intercourse, and current oral contraceptive pill use.