T Cell Mediated Immune Responses Against Mycobacterium Tuberculosis

One-third of the world’s population is estimated to be infected with Mycobacterium tuberculosis (M. tuberculosis) and remains asymptomatic. Of these, only 5-10% of the individuals are known to develop active tuberculosis in their lifetime. Host T cell mediated adaptive immune responses are of critical importance against M. tuberculosis infection. However the immune mechanisms that determine why some individuals are protected from disease while others develop infection are yet to be defined. This chapter aims to summarize the role of different T cell subsets against and their regulation against M. tuberculosis infection. INTRODUCTION The outcome of an infection with M. tuberculosis depends on the effect balance between the host innate and adaptive immune response. In most cases, the interaction between M. tuberculosis and the alveolar macrophage results in clearance of the bacillus. Multiple factors are involved in achieving this response and this chapter focuses on the role of adaptive immunity in mycobacterial clearance.