Comparison of bacterial microbiota in skin biopsies from normal and psoriatic skin

Abstract

Microorganisms have been implicated in the pathogenesis of psoriasis. Previous studies of psoriasis and normal skin have used swabs from the surface rather than skin biopsies. In this study, biopsies were taken from 10 patients with psoriasis and 12 control subjects from unmatched sites. Samples were analysed with massive parallel pyrosequencing on the 454 platform targeting the 16S rRNA gene and the variable regions V3-V4. The samples grouped into 19 phyla, 265 taxon and 652 operational units (OTUs) at 97% identity. A cut-off abundance level was set at 1%. The three most common phyla in both normal and psoriasis skin were Firmicutes (39% psoriasis, 43% normal skin), Proteobacteria (38% psoriasis, 27% normal skin) and Actinobacteria (5% psoriasis, 16% normal skin, p = 0.034). In trunk skin, Proteobacteria were present at significantly higher levels in psoriasis compared to controls (52 vs. 32%, p = 0.0113). The commonest genera were Streptococci in both psoriasis (32%) and normal skin (26%). Staphylococci were less common in psoriasis (5%) than in controls (16%), as were Propionibacteria (psoriasis 0.0001669%, controls 0.0254%). Both Staphylococci and Propionibacteria were significantly lower in psoriasis versus control limb skin (p = 0.051, 0.046, respectively). This study has shown some differences in microbiota between psoriasis and normal skin. Whether these are of primary aetiological significance, or secondary to the altered skin of psoriasis remains to be determined.

A systematic literature review of the human skin microbiome as biomarker for dermatological drug development

“…32. Similar inconsistencies in findings were also observed in those studies assessing the microbiota 28, 29, 30, 31, 34.…”

“…In 10 studies, the cutaneous microbiome in PV patients was investigated, Table 1 25, 26, 27, 28, 29, 30, 31, 32, 33, 34. In addition to microbiota, these studies have focused on the mycobiota.…”

Microbial Ecology of the Skin in the Era of Metagenomics and Molecular Microbiology

“…Analyses of the bacterial microbiota by 16S rRNA gene-based approaches in crosssectional studies suggest underrepresentation of Propionibacterium and increased representation of the phylum Firmicutes in psoriatic plaques as compared with healthy controls or uninvolved limb skin (Fig. 3B) (Gao et al 2008;Fahlen et al 2012). Longitudinal studies of the skin microbiota in psoriasis plaques may provide insight into the role of microbes in triggering, propagation, and maintenance of plaques.…”

Experimental metagenomics and ribosomal profiling of the human skin microbiome

“…Skin sampling can be performed using non-invasive swabs, [17,[39][40][41][42] biopsies [43,44] or scrapes. [42,45] Swabs are moistened with a buffer solution and are firmly rubbed back and forth for approximately 30 seconds over the skin area, [46] and the procedure can be repeated twice to maximize the amount of collected biomass.…”