Lipoarabinomannan (LAM)

Lipoarabinomannan (LAM) is a complex lipoglycan and a major structural component of the Mycobacterium tuberculosis cell wall, playing an essential role in the pathogenesis of tuberculosis (TB). It acts as a potent immunomodulator that facilitates the survival of mycobacteria within host macrophages by inhibiting phagosome-lysosome fusion and suppressing host T-cell activation (Nature Reviews Microbiology, 2013). LAM exists in several forms, most notably mannose-capped LAM (ManLAM), which interacts with host receptors like DC-SIGN and the mannose receptor to evade the immune response (Journal of Biological Chemistry, 2004). Clinically, LAM is highly significant as a diagnostic biomarker, specifically through the detection of urinary LAM (uLAM) in patients with advanced HIV and tuberculosis co-infection, a method supported by the World Health Organization (WHO Global Tuberculosis Report). Beyond diagnostics, LAM is a focus of therapeutic research involving the development of monoclonal antibodies for neutralization and the study of drugs like ethambutol that interfere with the synthesis of its arabinan core (Scientific Reports, 2017).

Other names

Mannose-capped lipoarabinomannanManLAMPhosphoinositol-capped lipoarabinomannanPILAMAraLAM

Inhibition of mycobacterial cell wall synthesis via arabinosyltransferase inhibition (e.g., Ethambutol) or diagnostic/therapeutic binding by monoclonal antibodies to neutralize immunomodulatory effects.