Targeted drug delivery to the macrophagic cellular tropics in tuberculosis

Tuberculosis (TB) is a bacterial infection caused by Mycobacterium tuberculosis and is known to be one of the deadliest diseases of the 21st century. This contagious disease has existed for ages and can be traced back to 9000 years. TB generally infects macrophages of alveoli and utilizes these cells as the main site for proliferation. The current conventional therapy for TB includes the administration of multiple antimicrobial medications for several months and has varied drawbacks, including the development of drug-resistant strains, severe adverse drug reactions, and poor patient compliance. Several new and improved strategies have been developed in recent years to address these issues, one of the approaches being targeted drug delivery. By directly targeting infected macrophages, targeted drug delivery offers a novel approach to overcoming many of the problems associated with conventional therapy. Recent advancements in nanotechnology have opened several ways to explore drug carriers that can actively target macrophages. By utilizing specialized ligands that engage with specific receptors present on macrophages, targeted nanocarriers facilitate delivery to the targeted site. This chapter, at the beginning briefs about the history of TB and the currently available treatment options to counteract it. Autophagy-induced nanomedicines and the role of different receptors like mannose, hyaluronic acid, tuftsin, and folate, which are overexpressed on macrophages and can be utilized with nanocarriers for active targeting have also been discussed. Finally, the chapter concludes with some challenges for macrophage-directed targeting for the management of TB.