Bacillus Calmette-Guérin mycobacterial surface (BCG surface)

The Bacillus Calmette-Guérin (BCG) mycobacterial surface is a complex, lipid-rich multi-molecular structure that serves as the primary interface between the attenuated Mycobacterium bovis strain and the host immune system. It is composed of various immunostimulatory molecules, including mycolic acids, lipoarabinomannan (LAM), and trehalose dimycolate (TDM), as well as proteins like fibronectin attachment protein (FAP) (Source: PMID: 24434717). In clinical practice, the BCG surface is the functional component of the BCG vaccine used for tuberculosis prevention and the gold-standard immunotherapy for non-muscle invasive bladder cancer. Its therapeutic effect is mediated by the binding of FAP to host fibronectin, followed by the activation of Toll-like receptors (TLR2 and TLR4) on macrophages and urothelial cells (Source: PMID: 26258544). This interaction triggers a robust Th1-polarized immune response, characterized by the secretion of cytokines such as IFN-gamma and IL-12, which recruit and activate cytotoxic T-lymphocytes and natural killer cells to eliminate tumor cells (Source: PMID: 11733463). While highly effective, the complexity of the BCG surface also presents challenges, including the risk of systemic infection and significant local toxicity.

Other names

BCG cell wallMycobacterium bovis BCG envelopeBCG surface antigensBCG cell wall skeletonBCG-CWS

Activation of host pattern recognition receptors (TLR2, TLR4, Dectin-1), induction of Th1-polarized cytokine production, and facilitation of bacterial attachment to the urothelium via fibronectin-binding proteins (Source: PMID: 24434717, PMID: 26258544).