Polyclonal T-cell receptors (TCRs) recognizing BCG-derived peptide–MHC complexes (BCG-specific TCRs)

Polyclonal T-cell receptors (TCRs) recognizing BCG-derived peptide–MHC complexes are a diverse population of immune receptors that mediate the cellular immune response against Mycobacterium bovis Bacillus Calmette-Guérin (BCG) (Kaufmann, 2001, Nature Reviews Immunology). These TCRs specifically bind to mycobacterial antigens, such as Ag85B or PPD, presented by Major Histocompatibility Complex (MHC) molecules on antigen-presenting cells or tumor cells (Sia et al., 2015, PLOS Pathogens). In the context of tuberculosis vaccination, these receptors are essential for establishing long-term protective immunity by generating memory T-cell populations. In oncology, particularly for non-muscle invasive bladder cancer (NMIBC), the activation of these TCRs via intravesical BCG instillation induces a potent anti-tumor immune response characterized by Th1 cytokine production and direct tumor cell lysis (Redelman-Sidi et al., 2014, Nature Reviews Urology). The interaction between these TCRs and BCG-derived peptides leads to T-cell activation, proliferation, and the recruitment of other immune effectors to the site of infection or malignancy. Understanding the repertoire and specificity of these polyclonal TCRs is vital for improving vaccine efficacy and developing next-generation TCR-based immunotherapies.

Other names

BCG-reactive T-cell receptorsMycobacterium bovis BCG-specific TCRsBCG-peptide-MHC-specific TCRsBCG-responsive T-cell receptors

Recognition of mycobacterial peptides presented by MHC molecules, leading to T-cell activation, cytokine secretion, and targeted cytotoxicity against infected or malignant cells.