KLK5 and rosacea: In the present study we illustrated TLR2-mediated inflammation in rosacea by assessing the expression of TLR2, the serine protease KLK5, cathelicidin peptides, the macrophage-specific marker CD68, and related inflammatory factors using immunohistochemistry staining in the skin from patients with rosacea, in addition to immunofluorescence staining, western blot, and RT-qPCR on samples from rosacea-like mice, revealing that TLR2, KLK5, cathelicidin, and CD68 were all highly expressed in rosacea and rosacea-like lesions.