Acne vulgaris is caused and aggravated by a number of different factors, among which colonisation of sebaceous glands with Propionibacterium acnes appears to play a key role in the etiology of the disease. Prop. acnes has been shown to produce and secrete a number of lipolytic enzymes, causing enzymatic degradation of sebum and production of pro-inflammatory metabolites from polyunsaturated fatty acids within glands. Furthermore, Prop. acnes recently has been shown to secrete a number of chemotactic polysaccharides attracting cutaneous cell types of relevance in mediating inflammatory responses. Thus, erradication of the pathogen appeared to be a suitable road for anti-acne therapy. A number of cosmetic and dermatologic principles based on broad spectrum antimicrobial efficacy against gram-positive and gram-negative microorganisms were developped and successfully marketed as anti-acne ingredients in the past. However, as most of the very efficient therapeuticals were obtained from the range of antibiotics, many of them had to be considered as pharmaceuticals requiring medical prescription. In addition, the risk of multiresistance of cutaneous pathogens, especially of Prop. acnes, against antibiotics commonly used in anti-acne therapy is presently dramatically increasing. As a result of excessive use of antibiotics a high proportion of cutaneous propionibacteria have already been rendered resistant against antibiotics commonly used in anti-acne therapy.In order to obtain novel principles for anti-acne therapy avoiding the risk of microbial resistance against the antimicrobial principles, lantibiotics were investigated for their antimicrobial efficacy against Prop. acnes. It could be demonstrated that a lantibiotic produced by Lactococcus lactis is highly effective in vitro and in vivo against cutaneous propionibacteria. Due to the high degree of selectivity towards coryneform bacteria the described lantibiotic is already effective against Prop. acnes in doses not affecting the remaining resident microflora of human skin, thus being a very mild, but also efficient antimicrobial against cutaneous propionibacteria. The evaluation of its biocompatibility revealed that it was of excellent biocompatibility and well tolerated by human volunteers. Furthermore, due to the fact that the biosynthesis of lantibiotics is not encoded by bacterial plasmids easily to be exchanged within the microbial community, but encoded on the bacterial chromosome itself, the risk of rapid generation of multiresistance against lantibiotics could be effectively avoided. As the GRAS status has already been assigned to the described lantibiotic by the FDA, and it has already been used extensively in the food industry for cheese preservation, convincing evidence has been accumulated in the past for the excellent tolerance of man to this lantibiotic. Thus a novel antimicrobial efficacy system based on a lantibiotic from Lactococcus lactis has been developped for the treatment of acne vulgaris in man.
