title: Characterization of adipose tissue macrophages and adipose-derived stem cells in critical wounds.
abstract: BACKGROUND
  Subcutaneous adipose tissue is a rich source of adipose tissue macrophages and adipose-derived stem cells which both play a key role in wound repair. While macrophages can be divided into the classically-activated M1 and the alternatively-activated M2 phenotype, ASCs are characterized by the expression of specific stem cell markers.
  
  
  METHODS
  In the present study, we have investigated the expression of common macrophage polarization and stem cell markers in acutely inflamed adipose tissue. Subcutaneous adipose tissue adjacent to acutely inflamed wounds of 20 patients and 20 healthy subjects were harvested and underwent qPCR and flow cytometry analysis.
  
  
  RESULTS
  Expression levels of the M1-specific markers CD80, iNOS, and IL-1b were significantly elevated in inflammatory adipose tissue when compared to healthy adipose tissue, whereas the M2-specific markers CD163 and TGF-βwere decreased. By flow cytometry, a significant shift of adipose tissue macrophage populations towards the M1 phenotype was confirmed. Furthermore, a decrease in the mesenchymal stem cell markers CD29, CD34, and CD105 was observed whereas CD73 and CD90 remained unchanged.
  
  
  CONCLUSIONS
  This is the first report describing the predominance of M1 adipose tissue macrophages and the reduction of stem cell marker expression in acutely inflamed, non-healing wounds.
authors.affiliation: Plastic and Reconstructive Surgery, Hand Surgery-Burn Center, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.|Department of Medicine, Yale University, New Haven, United States.|Institute of Biochemistry and Molecular Cell Biology, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Bong-Sung
authors.initials: BS
authors.lastname: Kim
authors.affiliation: Department of Medicine, Yale University, New Haven, United States.
authors.forename: Pathricia V
authors.initials: PV
authors.lastname: Tilstam
authors.affiliation: Plastic and Reconstructive Surgery, Hand Surgery-Burn Center, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Katrin
authors.initials: K
authors.lastname: Springenberg-Jung
authors.affiliation: Plastic and Reconstructive Surgery, Hand Surgery-Burn Center, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Arne Hendrick
authors.initials: AH
authors.lastname: Boecker
authors.affiliation: Institute of Biochemistry and Molecular Cell Biology, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Corinna
authors.initials: C
authors.lastname: Schmitz
authors.affiliation: Institute of Biochemistry and Molecular Cell Biology, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Heinrichs
authors.affiliation: Department of Immunology, Yale University, New Haven, United States.
authors.forename: Soo Seok
authors.initials: SS
authors.lastname: Hwang
authors.affiliation: Plastic and Reconstructive Surgery, Hand Surgery-Burn Center, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Jan Philipp
authors.initials: JP
authors.lastname: Stromps
authors.affiliation: Department of Orthopedic Trauma Surgery, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Bergita
authors.initials: B
authors.lastname: Ganse
authors.affiliation: Department of Intensive Care Medicine, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Ruedger
authors.initials: R
authors.lastname: Kopp
authors.affiliation: Department of Orthopedic Trauma Surgery, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Knobe
authors.affiliation: Department of Vascular Biology, Institute for Stroke and Dementia Research, Ludwig-Maximilians-Universität München (LMU), Munich, Germany.|Munich Cluster for Systems Neurology (SyNergy), Ludwig-Maximilians-Universität München (LMU), Munich, Germany.
authors.forename: Juergen
authors.initials: J
authors.lastname: Bernhagen
authors.affiliation: Plastic and Reconstructive Surgery, Hand Surgery-Burn Center, Rheinisch-Westfälische Technische Hochschule Aachen, Aachen, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Pallua
authors.affiliation: Department of Medicine, Yale University, New Haven, United States.
authors.forename: Richard
authors.initials: R
authors.lastname: Bucala
keywords: Adipose tissue; Adipose-derived stem cells; Inflammation; M1; M2; Macrophages; Polarization; Wound repair