Microbiome dynamics of human epidermis following skin barrier disruption.

Patrick Ljm Zeeuwen,Jos Boekhorst,Ellen H Van Den Bogaard,Peter Mc Van De Kerkhof,Heleen D De Koning,Joost Schalkwijk,Sacha Aft Van Hijum,Delphine M Saulnier,Iris I Van Swam,Michiel Kleerebezem,Harro M Timmerman

doi:10.1186/gb-2012-13-11-r101

Abstract

BackgroundRecent advances in sequencing technologies have enabled metagenomic analyses of many human body sites. Several studies have catalogued the composition of bacterial communities of the surface of human skin, mostly under static conditions in healthy volunteers. Skin injury will disturb the cutaneous homeostasis of the host tissue and its commensal microbiota, but the dynamics of this process have not been studied before. Here we analyzed the microbiota of the surface layer and the deeper layers of the stratum corneum of normal skin, and we investigated the dynamics of recolonization of skin microbiota following skin barrier disruption by tape stripping as a model of superficial injury.ResultsWe observed gender differences in microbiota composition and showed that bacteria are not uniformly distributed in the stratum corneum. Phylogenetic distance analysis was employed to follow microbiota development during recolonization of injured skin. Surprisingly, the developing neo-microbiome at day 14 was more similar to that of the deeper stratum corneum layers than to the initial surface microbiome. In addition, we also observed variation in the host response towards superficial injury as assessed by the induction of antimicrobial protein expression in epidermal keratinocytes.ConclusionsWe suggest that the microbiome of the deeper layers, rather than that of the superficial skin layer, may be regarded as the host indigenous microbiome. Characterization of the skin microbiome under dynamic conditions, and the ensuing response of the microbial community and host tissue, will shed further light on the complex interaction between resident bacteria and epidermis.

Highlights

Recent advances in sequencing technologies have enabled metagenomic analyses of many human body sites
We found that the upper buttock had the largest bacterial diversity of the analyzed sites: rarefaction curves show that the phylogenetic diversity observed in different body sites is highest in upper buttock skin for this limited number of samples (Figure 1b)
Based on our findings we here present a working model that there is a shortlived recolonization of the damaged skin with microbial constituents from the surrounding superficial skin layer and that this transient microbiome is replaced by the microbiome that inhabits the deeper layers of the stratum corneum (Figure 8)

Summary

Introduction

Recent advances in sequencing technologies have enabled metagenomic analyses of many human body sites. Several studies have catalogued the composition of bacterial communities of the surface of human skin, mostly under static conditions in healthy volunteers. Consortium started 5 years ago to characterize the human microbial communities present at specific body sites, including skin [5,6]. These efforts have recently resulted in an extensive map of the microbes that live in and on us [7,8]. As skin is relatively accessible, and invasive procedures to study skin injury in human subjects are available [10,11], we here studied the dynamics of the cutaneous microbiome in a model for standardized skin barrier disruption

Methods

Results

Discussion

Conclusion