title: Microbiome dynamics of human epidermis following skin barrier disruption.
abstract: BACKGROUND
  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. 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.
  
  
  RESULTS
  We 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.
  
  
  CONCLUSIONS
  We 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.
authors.forename: Patrick L J M
authors.initials: PL
authors.lastname: Zeeuwen
authors.forename: Jos
authors.initials: J
authors.lastname: Boekhorst
authors.forename: Ellen H
authors.initials: EH
authors.lastname: van den Bogaard
authors.forename: Heleen D
authors.initials: HD
authors.lastname: de Koning
authors.forename: Peter M C
authors.initials: PM
authors.lastname: van de Kerkhof
authors.forename: Delphine M
authors.initials: DM
authors.lastname: Saulnier
authors.forename: Iris I
authors.initials: II
authors.lastname: van Swam
authors.forename: Sacha A F T
authors.initials: SA
authors.lastname: van Hijum
authors.forename: Michiel
authors.initials: M
authors.lastname: Kleerebezem
authors.forename: Joost
authors.initials: J
authors.lastname: Schalkwijk
authors.forename: Harro M
authors.initials: HM
authors.lastname: Timmerman
mesh_terms: D000328:Adult; D004817:Epidermis / Q000276:immunology / Q000293:injuries / Q000382:microbiology*; D005260:Female; D006801:Humans; D015603:Keratinocytes / Q000378:metabolism / Q000382:microbiology; D008297:Male; D064307:Microbiota; D010802:Phylogeny; D012329:RNA, Bacterial / Q000032:analysis; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D017422:Sequence Analysis, DNA; D012867:Skin / Q000276:immunology / Q000382:microbiology*
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S