RAB27A and leukemia: After differentiation into mature macrophage-like cells by Phorbol 12-myristate 13-acae-tate (PMA) stimulation for 7 days, human monocytic leukemia cells (THP-1 cells) were then infected with Bacillus Calmette–Guérin (BCG) vaccine, which is an attenuated form of Mycobacterium bovis, with or without inhibiting small EV biogenesis or secretion using siRNA oligos against Alix or Rab27a, as previously described (Figure 5A,B) [24].