KLK5 and Papule: Cathelicidin is further cleaved into LL-37, its active peptide form, by kallikrein 5 (KLK5), causing leukocyte chemotaxis, activation of NF-kB and promotion of angiogenesis [103,104], resulting in morphologic changes in rosacea, such as telangiectasia, facial erythema, papules and pustules.