Development of a Drug Delivery System using a Model that Mimics Chronic Infection of Mycobacterium bovis Calmette-Guérin in Alveolar Macrophages

Abstract

Macrophages play a dominant role in defense against infective organisms and their regarded abilities can be positioned as their most primitive and important function. On the other hand, tuberculosis, caused by tubercle bacilli which possess the ability to survive in phagosome and grow in cell, poses a serious problem as an intractable disease because the efficacy of drug delivery to the target bacilli is low. We have developed a new approach to therapy against intracellular bacteria using a drug delivery system (DDS), to deliver an effective amount of drug to the target site, based on the phagocytotic ability of macrophages. In this review, the development of an in vitro model of chronic infection by tubercle bacilli and therapy against tuberculosis using phagocytosis by macrophages and a DDS with microspheres are described.