The role of cytokines in chlamydial infections

Chlamydiae are important human pathogens responsible for a wide range of infections and diseases. Chronic infections can be particularly devastating, as shown by diseases caused by Chlamydia trachomatis, such as trachoma and post-infectious tubal infertility, or possibly associated with Chlamydia pneumoniae, such as atherosclerosis. Cytokines are likely to be involved for the early resolution of chlamydial infections. However, recent data suggest a role played by cytokines in establishing chlamydial persistence, thus possibly contributing to chronic disease through immunopathological responses. Recent information from in-vitro cell culture systems and experimental animal models is discussed. Moreover, some new evidence about the effector functions of other immune mediators is presented.