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Toll-like receptor 2 in host defense against Mycobacterium tuberculosis: to be or not to be-that is the question.

ABSTRACT: Toll-like receptor (TLR) 2 is expressed on immune cells and respiratory epithelial cells lining the lung. TLR2 is not critical for protection during acute Mycobacterium tuberculosis (Mtb) infection but it has a significant multi-faceted role in containing chronic infection. This review highlights the contribution of TLR2 to host protection, immune evasion by Mtb and immune regulation during chronic Mtb infection. The TLR2-triggered pro-inflammatory cytokines initiate protective mechanisms and limit Mtb replication while the immune evasion pathways counterattack anti-bacterial effector mechanisms. The immune regulation pathways that are activated dampen TLR2 signaling. The combinatorial effect of these functional responses is persistence of Mtb with minimal immunopathology.

SUBMITTER: Gopalakrishnan A

PROVIDER: S-EPMC5086274 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature

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Toll-like receptor 2 in host defense against Mycobacterium tuberculosis: to be or not to be-that is the question.

Gopalakrishnan Archana A Salgame Padmini P

Current opinion in immunology 20160618

Toll-like receptor (TLR) 2 is expressed on immune cells and respiratory epithelial cells lining the lung. TLR2 is not critical for protection during acute Mycobacterium tuberculosis (Mtb) infection but it has a significant multi-faceted role in containing chronic infection. This review highlights the contribution of TLR2 to host protection, immune evasion by Mtb and immune regulation during chronic Mtb infection. The TLR2-triggered pro-inflammatory cytokines initiate protective mechanisms and li ...[more]

PMID: 27326654

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