J Allergy Clin Immunol. 2009 Sep; 124(3S2): R13-R18Schauber J, Gallo RLOur skin is constantly challenged by microbes but is rarely infected. Cutaneous production of antimicrobial peptides (AMPs) is a primary system for protection, and expression of some AMPs further increases in response to microbial invasion. Cathelicidins are unique AMPs that protect the skin through 2 distinct pathways: (1) direct antimicrobial activity and (2) initiation of a host response resulting in cytokine release, inflammation, angiogenesis, and reepithelialization. Cathelicidin dysfunction emerges as a central factor in the pathogenesis of several cutaneous diseases, including atopic dermatitis, in which cathelicidin is suppressed; rosacea, in which cathelicidin peptides are abnormally processed to forms that induce inflammation; and psoriasis, in which cathelicidin peptide converts self-DNA to a potent stimulus in an autoinflammatory cascade. Recent work identified vitamin D3 as a major factor involved in the regulation of cathelicidin. Therapies targeting control of cathelicidin and other AMPs might provide new approaches in the management of infectious and inflammatory skin diseases.
Rosacea is a common skin condition but the treatments currently available are not satisfactory. OBJECTIVES: To assess the efficacy of intense pulsed light (IPL) for treatment of stage I rosacea (flushing, erythema and telangiectasia). METHODS: Thirty-four patients were treated, 25 women and nine men, mean age 47 years. The treatment employed was IPL 515-1200 nm, with a 560 nm cut-off filter. The fluence range was 24-32 J cm(-2). Four treatments were administered on the face at 3-week intervals. Erythema values were measured at baseline and at the end of the treatment period on the cheeks and chin. Digital photographs were assessed by a consultant dermatologist on a 10-point visual analogue scale (VAS). Patients' assessments were also made using a 10-point VAS. Outcome measures were repeated 6 months after treatment. RESULTS: After four treatments the mean reduction of the erythema values was 39% on the cheeks (P The severity of rosacea was reduced on average by 3.5 points on the 10...