Microreview The innate immune response in human tuberculosis

Summary Mycobacterium tuberculosis (Mtb) infection can becleared by the innate immune system before theinitiation of an adaptive immune response. Thisinnate protection requires a variety of robust cellautonomous responses from many different hostimmune cell types. However, Mtb has evolvedstrategies to circumvent some of these defences.In this mini-review, we discuss these host–pathogen interactions with a focus on studies per-formed in human cells and/or supported by humangenetics studies (such as genome-wide associa-tion studies).Introduction Mycobacterium tuberculosis (Mtb) is particularly effectiveat subverting many of the host immune defences, and thisis one reason why it is such a successful human pathogenthat has been particularly hard to eradicate. The outcomeof infection by Mtb and therefore the clinical manifestationof tuberculosis (TB) depend on many combined factors,such as host genetics, bacterial genetics (virulencefactors), the health and nutritional status of the host andwhether there has been any prior exposure/immunity andvaccination history. Around half of individuals exposed toMtb do not exhibit a positive tuberculin skin test (Morrison