PTGS2 and infection: Indeed, it was shown that infection of macrophages with the M. tuberculosis vaccine strain Bacille Calmette-Guérin (BCG) leads to both an accumulation of LDs containing cyclooxygenase-2 (COX-2) on their surface, and enhanced production of PGE2, suggesting that LDs may serve as platforms for eicosanoid production during mycobacterial infection [19,20].