 Cathelicidin is cleaved into the antimicrobial peptide LL-37 by both kallikrein 5 and kallikrein 7 serine proteases.Excessive production of LL-37 is suspected to be a contributing cause in all subtypes of Rosacea.Antibiotics have been used in the past to treat rosacea, but antibiotics may only work because they inhibit some SCTEs.