Activities of First-Choice Antimicrobials against Gamma Interferon-Treated Chlamydia trachomatis Differ in Hypoxia

Gamma interferon (IFN-gamma)-mediated host responses play a central role in resolving genital Chlamydia trachomatis infections but may also result in persistence of the pathogen, which shows reduced susceptibility to antimicrobials. The antichlamydial function of IFN-gamma is oxygen dependent, and the efficacy of antimicrobials against C. trachomatis is reduced in a low-oxygen environment. In this study, we show that the antichlamydial efficacies of azithromycin and doxycycline differ in IFN-gamma-treated cells under hypoxia.