Different species of Propionibacterium acnes contribute to healthy skin
Jan 05, 2016
The mainstay treatment of acne has involved the targeting of p.Acnes as a critical component, however different p.Acnes strains are actually involved in healthy skin. Not everyone who has p.Acnes as a part of the skin microflora develop acne.
Research conducted at UCLA and published in the Journal of Investigative Dermatology, identified that some strains of the bacteria caused acne, whereas other strains resulted in healthy skin.
By combining a metagenomic study of the skin microbiome and genome sequencing of this major skin commensal, this study provides insight into potential bacterial genetic determinants in acne pathogenesis and emphasizes theimportance of strain-level analysis of the human microbiometo understand the role of commensals in health and disease.
The researchers sampled the pilosebaceous units of 49 acne patients and 52 healthy individuals by removing P. acnes bacteria with OTC pore strips. After extracting the microbial DNA from the strips, the researchers tracked a genetic marker to identify the bacterial strains in each volunteer's pores and recorded whether the person suffered from acne. They then cultured the bacteria from the strips to isolate more than 1,000 strains.
Analysis of the strains was done on a genomic level. Acne and non acne skins both had an abundance of P. acnes, however, the strain population structures were significantly different.
Certain strains were highly associated with acne, and other strains were enriched in healthy skin. Washington University scientists sequenced 66 previously unreported P. acnes strains and compared 71 P. acnes genomes, enabling researchers to identify genes unique to each strain that are associated with acne or healthy skin.
The researchers found two strains of P. acnes that appeared in 20% of those with acne but in few healthy skin individuals. In addition, they found a third strain that is common in healthy skin but not found in acneic skin. The researchers believe the third strain may defend the skin from harmful acne bacteria and may be used as a future skin care target to prevent or treat acne.
Each unique DNA sequence (allele) was called a Ribotype. The most abundant P. acnes sequence was defined as ribotype 1 (RT1). Ribotype 8 and 10 were not found on normal skin but was found on acneic skins. Ribotypes 4, 5, 7, 8, 9, and 10 were found predominantly in acne patients, with four of these six ribotypes being statistically significantly enriched in acne. Ribotypes 4, 5, and 10 contain a nucleotide substitution in the DNA sequence,
The path for probiotics has been set for a cream that kills the bad strains of P. acnes while preserving the good strains.
References:
Fitz-Gibbon, S; Tomida, S; Chiu, B-H; Nguyen, L; Du, C; Liu, M; Elashoff, D; Erfe, M; Loncaric, A; Kim, J; Modlin, R; Miller, J; Sodergren, E; Craft, N; Weinstock, G; Li, H. (2013) Propionibacterium acnes Strain Populations in the Human Skin Microbiome Associated with Acne. Journal of Investigative Dermatology, 133 (9).
Be the first to know.
Subscribe to our newsletter for regular updates and announcements.
