However, this function is poorly studied in mycobacterial infections, and it could be of great importance as MPO exerts an antimicrobial activity against Mycobacterium [66], and it is worth mentioning that MPO+ (azurophilic) granules are released last, and therefore, secretory vesicles, tertiary and secondary granules could be acting on bacteria much earlier. Here, MPO is linked to Mycobacterium infection.