CAMP and type 2 diabetes mellitus: Vitamin D directly and indirectly regulates the expression of the antimicrobial peptides cathelicidin (LL-37) and human β defensin-2 (HBD2), which exert bactericidal activity [15, 16], Because low sera levels of vitamin D were associated with significantly higher intracellular mycobacterial growth, we decided to evaluate the expression of LL-37 and HBD2 in monocytes from T2D patients with lower sera vitamin D levels in comparison with monocytes from healthy volunteers with adequate serum vitamin D levels.