TECHNICAL ASPECTS OF CHLAMYDIA TRACHOMATIS ANTIMICROBIAL SUSCEPTIBILITY TESTING IN CELL CULTURE SYSTEM

Chlamydia trachomatis (C. frachomatis) is the most common bacterial agent of sexually transmitted infections and an obligate intracellular bacterium with a unique life cycle. Cell culture systems using McCoy cells and immunofluorescent staining to identify characteristic chlamydial inclusions represent the most common methodology employed in antimicrobial susceptibility testing of this prevalent pathogen. The testing process can be broken down into four technical steps - preisolation stage, isolation of C. frachomatis in cell culture, preparatory steps for antimicrobial susceptibility testing and, finally, testing phase with a determination of minimal inhibitory concentration (MIC) and minimal chlamydicidal concentration (MCC). As this technique requires precision and careful attention to conditions which may influence both the ability of chlamydial organisms to infect cells in culture and the efficacy of a tested antibiotic through mechanisms such as intracellular uptake, following these steps is pivotal in order to ensure reproducibility and comparability of obtained results.