T-cell receptor recognizing mycobacterial peptide–MHC class II complexes (TCR-mycobacterial pMHCII)

The T-cell receptor (TCR) recognizing mycobacterial peptide–MHC class II complexes is a specialized heterodimeric protein complex essential for the adaptive immune response against Mycobacterium tuberculosis and related pathogens (Sia et al., 2015, Nature Reviews Immunology). Located on the surface of CD4+ T cells, these receptors specifically identify mycobacterial antigens that have been processed and presented by Major Histocompatibility Complex (MHC) class II molecules on antigen-presenting cells (Kaufmann, 2010, Nature Reviews Microbiology). This recognition event is the critical first step in T-cell activation, leading to the secretion of pro-inflammatory cytokines such as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α), which orchestrate the activation of macrophages to control intracellular infection (Flynn & Chan, 2001, Annual Review of Immunology). In clinical medicine, this interaction is exploited for diagnostics through Interferon-Gamma Release Assays (IGRAs) and is the primary focus of global vaccine development efforts, including the BCG vaccine and novel candidates like M72/AS01E (Tait et al., 2019, NEJM). Furthermore, advanced therapeutic strategies are exploring the use of TCR-engineered T cells to provide potent, antigen-specific immunity for patients with drug-resistant tuberculosis (Ogongo et al., 2021, Frontiers in Immunology). The effectiveness of these interventions is often influenced by the high degree of HLA polymorphism in human populations and the potential for mycobacterial strains to evolve epitopes that evade TCR recognition.

Other names

Mycobacterium-specific T-cell receptorMHC class II-restricted T-cell receptorMTB-specific TCRMycobacterial antigen-specific T-cell receptor

Activation of CD4+ T cells through the specific recognition of mycobacterial peptides presented by MHC class II molecules, leading to a protective Th1-mediated immune response and macrophage activation.