Usefulness of Chinese Herbal Medicines as Host-Directed Therapeutics against Mycobacterial Infections: A Review.

The high incidence of tuberculosis (TB) in developing countries, the resurgence of TB in industrialized countries, and the worldwide increase in the prevalence of Mycobacterium avium complex infections have prompted the quest for new antimycobacterial drugs. However, the development of such chemotherapeutics is currently making very slow progress. It therefore appears that devising improved administration protocols for clinical treatment against intractable mycobacteriosis using existing chemotherapeutics is more practical than awaiting the development of novel antimycobacterial drugs. The modulation of host immune responses using immunoadjunctive agents may increase the efficacy of antimicrobial treatment against mycobacteriosis. Particularly, the mild and long-term up-regulation of host immune reactions against mycobacterial pathogens using Chinese herbal medicines (CHMs) may be beneficial for immunoadjunctive therapy. This review focuses on the current status and future prospects regarding the development of CHMs that can be useful for the clinical control of intractable mycobacterial infections.