Cathelicidin (CAMP, LL-37 and hCAP), is a major protein in specific granules of neutrophils (Sorensen O et al. 1997). CAMP is also present in subpopulations of lymphocytes and monocytes, squamous epithelial cells and keratinocytes (Agerberth B et al. 2000; Frohm M et al. 1997; Frohm Nilsson M et al. 1999). CAMP is synthesized as preproprotein (Zanetti M et al. 1995). After removal of the signal peptide, CAMP(31-170) is stored in granules as an inactive proform (Sorensen OE et al. 2001). CAMP (31-170) was shown to be processed extracellularly to the active antimicrobial peptide LL-37 (CAMP(134-170)) by proteinase 3 (PRTN3) (Sorensen OE et al. 2001).