Water-Filtered Infrared A (wIRA) Irradiation: Novel Treatment Options for Chlamydial Infections

Abstract

AbstractwIRA has been shown to reduce extracellular chlamydial forms and intracellular chlamydial inclusions in different cell culture infection models, and similarly on different human or animal chlamydial species. Repeated wIRA applications increase the efficacy of treatment in vitro, and in vivo in a guinea pig ocular model of inclusion conjunctivitis. The guinea pig model reflects the human ocular disease trachoma, the most common cause of infectious blindness worldwide which is caused by ocular strains of Chlamydia trachomatis. In this model, ocular wIRA treatment reduces conjunctival chlamydial load and ocular pathology. First insights into the mechanisms of anti-chlamydial activity indicate the involvement of both thermal and non-thermal effects. Interestingly, wIRA treatment of non-infected cells renders them more resistant to subsequent chlamydial infection, suggesting cell-related mechanisms that might involve cytochrome C. Further studies envisage the refinement of wIRA treatment protocols, the enhancement of anti-chlamydial activity by adding photodynamic substances, and characterization of the mechanisms underlying the therapeutic benefit of wIRA.