Recent progress in the research about Propionibacterium acnes strain diversity and acne: pathogen or bystander?

Abstract

Recent progress has steadily reported the existence of the diverse strains of Propionibacterium acnes, and these studies have contributed to the elucidation of their contradictory roles between normal commensals and pathogens. In this review, the authors aimed to provide an update on the recent understanding of research about P. acnes strain diversity and acne, analyzing the potential implications for clinical applications. Before the era of genomic research, P. acnes was known to be distinguished based on serological agglutination tests, cell wall sugar analysis, or fermentation traits. Since the complete genome sequence of P. acnes was first deciphered, genetic studies based on sequence data have expanded with the introduction of more refined and precise DNA-based typing methods, including multilocus sequence typing and metagenomics. These sophisticated techniques have revealed that P. acnes consists of phylogenetically distinct cluster groups with various pathogenic traits, including elicitation of inflammation, protein secretome profile, and unique distribution patterns in various skin loci. In following large-scale studies from patients' acne samples have revealed that specific sequence types are included within the phylogenetic divisions and further suggested that particular P. acnes strains play an etiologic role in acne while others are associated with health, providing a firm platform for evidential-based research into the exact role of this organism in acne. We strongly believe that future research would provide fruitful results in not only clarifying the apparent controversy with respect to roles of P. acnes but also developing therapeutic drugs by pinpointing specific targets of the pathogenic strain only.

Cutibacterium acnes (Propionibacterium acnes) and acne vulgaris: a brief look at the latest updates

“…Phylogenic studies also showed that acquired DNA sequences and bacterial immune elements may have roles in determining virulence properties of C. acnes strains. Moreover, biochemical, transcriptomic and proteomic analyses demonstrated that C. acnes phylotypes exhibit differences in inflammatory potential and expression of various putative virulence factors that may explain their distinct involvement in acne disease . These factors include neuraminidase, lipase, polyunsaturated fatty acid isomerase, the iron acquisition protein HtaA (a highly immunoreactive cell surface antigen) and heat shock proteins (HSP20, DnaK, DnaJ, GrpE and GroEL) .…”

“…Moreover, biochemical, transcriptomic and proteomic analyses demonstrated that C. acnes phylotypes exhibit differences in inflammatory potential and expression of various putative virulence factors that may explain their distinct involvement in acne disease. 40,42 These factors include neuraminidase, lipase, polyunsaturated fatty acid isomerase, the iron acquisition protein HtaA (a highly immunoreactive cell surface antigen) and heat shock proteins (HSP20, DnaK, DnaJ, GrpE and GroEL). 3 Host-interacting factors, such as CAMP factors, hemolysins and dermatan sulphate-binding adhesins (DsA1 and DsA2) have also been identified as possible pathogenic factors.…”

The role of the skin microbiota in acne pathophysiology

“…Microbial dysbiosis of C. acnes , Malassezia , bacteriophages, and perhaps other microbes, coupled with disturbed skin barrier formation and immune responses, are all factors correlated with acne . A recent metagenomic study that compared acne skin with healthy skin revealed that the balance among bacterial, fungal and bacteriophage components was important in the maintenance of skin health . Microbial dysbiosis can influence innate immunity through multiple targets, which include peroxisome proliferator‐activated receptors, interferon signalling, tumour necrosis factor activation, ILs and Toll‐like receptors.…”

“…43,61,62 A recent metagenomic study that compared acne skin with healthy skin revealed that the balance among bacterial, fungal and bacteriophage components was important in the maintenance of skin health. 11,66 Microbial dysbiosis can influence innate immunity through multiple targets, which include peroxisome proliferator-activated receptors, interferon signalling, tumour necrosis factor activation, ILs and Toll-like receptors. Matrix metalloprotease activity, being one of the factors of innate immunity response to C. acnes, has also been proposed as a cause of hyperkeratinization in pilosebaceous units, which is important for acne pathogenesis.…”

Edible Plants and Their Influence on the Gut Microbiome and Acne

“…The role of P. acnes is not clear, as this bacterium is ubiquitous. However, certain strains of acne may be more associated with acne and be pro-inflammatory [4,5,6]. Regardless of the ongoing debate regarding P. acnes , antibiotics used in the treatment of acne appear to have anti-inflammatory effects independent of their antimicrobial effects [7,8,9].…”