Affiliations: Department of Basic Laboratory Sciences, Osaka
University Graduate School of Medicine, Suita 565-0871, Japan | University of South Florida College of Medicine,
Tampa, FL 33612, USA
Abstract: Bacterial pneumonia in immunocompromised patients as well as elderly
persons often becomes a life threatening disease, even when effective
antibiotics are used extensively. In addition, the appearance of
antibiotic-resistant bacteria in medical facilities as well as in patients
requires another approach to treat such patients besides treatment with
antibiotics. In this regard, green tea catechins, such as epigallocatechin
gallate (EGCg), may be one of the potential agents for such purpose due to its
possible potential immunomodulatory as well as antimicrobial activity. The
studies by us showed that EGCg enhanced the in vitro resistance of
alveolar macrophages to Legionella pneumophila infection by selective
immunomodulatory effects on cytokine formation. Furthermore, the tobacco
smoking-induced impairment of alveolar macrophages regarding antibacterial as
well as immune activity was also recovered by EGCg treatment. These results
indicate that EGCg may be a possible potential immunotherapeutic agent against
respiratory infections in immunocompromised patients, such as heavy
smokers.
