Microbiome in healthy skin, update for dermatologists

Abstract

The skin is a complex barrier organ made of a symbiotic relationship between microbial communities and host tissue via complex signals provided by the innate and the adaptive immune systems. It is constantly exposed to various endogenous and exogenous factors which impact this balanced system potentially leading to inflammatory skin conditions comprising infections, allergies or autoimmune diseases. Unlike the gut and stool microbiome which has been studied and described for many years, investigations on the skin or scalp microbiome only started recently. Researchers in microbiology and dermatology started using modern methods such as pyrosequencing assays of bacterial 16S rRNA genes to identify and characterize the different microorganisms present on the skin, to evaluate the bacterial diversity and their relative abundance and to understand how microbial diversity may contribute to skin health and dermatological conditions. This article aims to provide an overview on the knowledge about the skin microbiota, the microbiome and their importance in dermatology.

Dirty Money: A Matter of Bacterial Survival, Adherence, and Toxicity

“…Both banknotes and coins are predominantly handled by multiple humans through touch. The overall human skin microbiome is arguably dominated by four main bacterial phyla: Firmicutes, Actinobacteria, Proteobacteria, and Bacteroidetes [13,14,15], while the hand microbiome is dominated by the Proteobacteria and Bacteroidetes [13,15]. The microbiota of hands can be divided into two groups: firstly, there are the resident microorganisms, which represent a relatively fixed group of microorganisms whose makeup changes very little and tend to recover rapidly following perturbation.…”

“…The microbiota of hands can be divided into two groups: firstly, there are the resident microorganisms, which represent a relatively fixed group of microorganisms whose makeup changes very little and tend to recover rapidly following perturbation. Secondly, there is a group of transient microorganisms that rarely establish a permanent residency on the skin but might exist because of external environmental exposures that might persist for a few hours up to a couple of days [15]. We therefore argue that the most likely source of the microorganisms on currency originates from humans [13,14,15,16,17,18] and could be considered as a heterogeneous microbiome.…”

The microbiome in preadolescent acne: Assessment and prospective analysis of the influence of benzoyl peroxide

“…This prospective, open‐label trial of evaluating the microbiome of preadolescent acne was performed at a single institution in Southern California, where factors of ultraviolet/visible light, heat, and population demographics, such as age and BMI, can influence acne severity . Boys were not included in the study, which limits the external validity.…”

“…In contrast, some researchers have suggested that the predominance of C. acnes is a byproduct of inflammation rather than an initiator or amplifier . Regardless, current literature supports C. acnes as the most prevalent species in sebaceous areas in adults, and this species creates an inhospitable environment for certain pathogens to cultivate …”

Alternative test models for skin ageing research

“…This approach was selected as one of the 10 insights of the decade in Science in 2010 and has progressed rapidly over the past few years due to 2 national projects, Metagenomics of the Human Intestinal Tract (MetaHIT) in the EU and the Human Microbiome Project (HMP) in the United States in 2008. Unlike the gut and stool microbiome, investigations of the skin microbiome began only recently . Shibagaki et al reported alterations of the skin microbiome in relation to skin ageing.…”