Mycobacterium tuberculosis ESAT6 Drives the Activation and Maturation of Bone Marrow-Derived Dendritic Cells via TLR4-Mediated Signaling

• Published in: Immune network Vol. 19; no. 2; pp. e13 - 10
• Main Authors: Jang, Ah-Ra, Kim, Green, Hong, Jung Joo, Kang, Soon Myung, Shin, Sung Jae, Park, Jong-Hwan
• Format: Journal Article
• Language: English
• Published: Korea (South) The Korean Association of Immunologists 01.04.2019; 대한면역학회
• Subjects: Brief Communication; 면역학; Dendritic cells; Mycobacterium tuberculosis; ESAT6 protein; TLR4 receptor
• ISSN: 1598-2629; 2092-6685
• DOI: 10.4110/in.2019.19.e13

6-kDa early secretory antigenic target (ESAT6), a virulent factor of , is involved in immune regulation. However, the underlying mechanism behind the activation and maturation of dendritic cells (DCs) by ESAT6 remains unclear. In this study, we investigated the effect on TLRs signaling on the regulation of ESAT6-induced activation and maturation of DCs. ESAT6 induced production of IL-6, TNF-α, and IL-12p40 in bone marrow-derived dendritic cells (BMDCs) from wild-type and TLR2-deficient mice, with this induction abolished in TLR4-deficient cells. NF-κB is essential for the ESAT6-induced production of the cytokines in BMDCs. TLR4 was also required for ESAT6-induced activation of NF-κB and MAPKs in BMDCs. ESAT6 additionally upregulated the expression of surface molecules CD80, CD86, and MHC-II, and also promoted the ability of CD4 T cells to secrete IFN-γ via the TLR4-dependent pathway. Our findings suggest that TLR4 is critical in the activation and maturation of DCs in response to ESAT6.