Substantial Alterations of the Cutaneous Bacterial Biota in Psoriatic Lesions

Abstract

For psoriasis, an idiopathic inflammatory disorder of the skin, the microbial biota has not been defined using cultivation-independent methods. We used broad-range 16S rDNA PCR for archaea and bacteria to examine the microbiota of normal and psoriatic skin. From 6 patients, 19 cutaneous samples (13 from diseased skin and 6 from normal skin) were obtained. Extracted DNA was subjected to the broad range PCR, and 1,925 cloned products were compared with 2,038 products previously reported from healthy persons. Using 98% sequence identity as a species boundary, 1,841 (95.6%) clones were similar to known bacterial 16S rDNA, representing 6 phyla, 86 genera, or 189 species-level operational taxonomic unit (SLOTU); 84 (4.4%) clones with <98% identity probably represented novel species. The most abundant and diverse phylum populating the psoriatic lesions was Firmicutes (46.2%), significantly (P<0.001) overrepresented, compared to the samples from uninvolved skin of the patients (39.0%) and healthy persons (24.4%). In contrast, Actinobacteria, the most prevalent and diverse phylum in normal skin samples from both healthy persons (47.6%) and the patients (47.8%), was significantly (P<0.01) underrepresented in the psoriatic lesion samples (37.3%). Representation of Propionibacterium species were lower in the psoriatic lesions (2.9±5.5%) than from normal persons (21.1±18.2%; P<0.001), whereas normal skin from the psoriatic patients showed intermediate levels (12.3±21.6%). We conclude that psoriasis is associated with substantial alteration in the composition and representation of the cutaneous bacterial biota.

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.…”

Expert consensus document: The International Scientific Association for Probiotics and Prebiotics (ISAPP) consensus statement on the definition and scope of prebiotics

“…The ability to increase water retention on the skin and reduce erythema formation is an emerging attribute of GOS ingestion, as reported in mouse studies 68 . On the skin, application of a prebiotic might stimulate changes in bacterial 69 or fungal 70 profiles perhaps by targeting epidermal growth factor receptor. The health consequences of this approach are currently unclear, but might include psoriasis, acne, dermatitis, eczema and wound development 66,67,71 .…”

Distinct cutaneous bacterial assemblages in a sampling of South American Amerindians and US residents

“…Investigators now are using molecular, DNA-based methodologies to assess the microbial populations present in and on human skin (Fredricks, 2001;Paulino et al, 2006Paulino et al, , 2008Gao et al, 2007Gao et al, , 2008Gao et al, , 2010Fierer et al, 2008Fierer et al, , 2010Grice et al, 2008Grice et al, , 2009Costello et al, 2009;Grice and Segre, 2011). However, these studies were all performed in humans who live in developed countries, as does the large-scale National Institute of Health (NIH)-initiated Human Microbiome Project (Peterson et al, 2009), that shares this focus on humans living lifestyles associated with postmodern socioeconomic development.…”

“…We sought to describe the composition and uniformity of the sampled Amerindian cutaneous microbiome in a community of Amerindian subjects, to identify correlates with particular clustering patterns, and to determine whether Amerindian and US populations could be distinguished. For these studies, we sampled a single cutaneous site, the volar mid-forearm, as this site is easily identified and sampled, permits examining laterality of populations, is washed less than hands, and is subject to an extensive sequence database that is currently growing (Paulino et al, 2006;Gao et al, 2007Gao et al, , 2008Gao et al, , 2010Paulino et al, 2008;Costello et al, 2009;Staudinger et al, 2011).…”