title: Abrasion arthroplasty increases mesenchymal stem cell content of postoperative joint effusions.
abstract: BACKGROUND
  Abrasion arthroplasty (AAP) is a procedure by which intrinsic cartilage healing is believed to be stimulated. Although clinically accepted for degenerative and traumatic cartilage lesions scientific evidence at a molecular level that proves the effect of AAP is scarce.
  
  
  METHODS
  Mononuclear cells were extracted from postoperative joint effusions 21.5 h post AAP and simple debridement of cartilage lesions. Luminex, ELISA and FACS experiments were performed. Immunohistochemical stainings of cell cultures for cartilage markers were used to confirm the findings.
  
  
  RESULTS
  Postoperative joint effusions after AAP showed increased contents of Mononuclear cells compared to Arthroscopic Chondroplasty (ACP). BMP-4 and IGF were increased in AAP as complared to ACP. Mononuclear cells isolated after AAP express the MSC markers CD 73, CD 105, CD 90, CD 44 and are CD34 negative. Chondrogenic differentiation was demonstrated by positive staining for Sox9, collagen II, proteoglycan, chondroitin-4-sulfate.
  
  
  CONCLUSIONS
  Our results support the clinical application of AAP as a procedure that enhances cartilage repair as an alternative to far more complex procedures that have gained popularity. Furthermore the data presented supports clinical investigations that recommend not to use suction drainage as by this procedure a considerable amount of the regeneratory potential of postoperative joint effusions might be extracted.
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. rbeckmann@ukaachen.de.
authors.forename: Rainer
authors.initials: R
authors.lastname: Beckmann
authors.affiliation: Department of Trauma, University Hospital of Kiel, Kiel, Germany. Sebastian.Lippross@uksh.de.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Lippross
authors.affiliation: Department of Trauma and Orthopaedics, University Hospital Heidelberg, Bergheim, Germany. claudiahartz@hotmail.de.
authors.forename: Claudia
authors.initials: C
authors.lastname: Hartz
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. mtohidnezhad@ukaachen.de.
authors.forename: Mersedeh
authors.initials: M
authors.lastname: Tohidnezhad
authors.affiliation: Department of Hematology, Oncology and Stem Cell Transplantation, Medical Faculty, RWTH Aachen, Aachen, Germany. mventuraferreira@ukaachen.de.
authors.forename: Mónica S Ventura
authors.initials: MS
authors.lastname: Ferreira
authors.affiliation: Department of Hematology, Oncology and Stem Cell Transplantation, Medical Faculty, RWTH Aachen, Aachen, Germany. sabine.neuss@post.rwth-aachen.de.
authors.forename: Sabine
authors.initials: S
authors.lastname: Neuss-Stein
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. andreas.seekamp@uksh-kiel.de.
authors.forename: Andreas
authors.initials: A
authors.lastname: Seekamp
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. snebelung@ukaachen.de.|Department of Orthopaedic Surgery, RWTH Aachen University, Aachen, Germany. snebelung@ukaachen.de.
authors.forename: Sven
authors.initials: S
authors.lastname: Nebelung
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. nkweider@ukaachen.de.
authors.forename: Nisreen
authors.initials: N
authors.lastname: Kweider
authors.affiliation: Department of Orthopaedic Surgery, RWTH Aachen University, Aachen, Germany. brath@ukaachen.de.
authors.forename: Björn
authors.initials: B
authors.lastname: Rath
authors.affiliation: Department of Orthopaedic Surgery, RWTH Aachen University, Aachen, Germany. hjahr@ukaachen.de.
authors.forename: Holger
authors.initials: H
authors.lastname: Jahr
authors.affiliation: Department of Anatomy and Cell Biology, RWTH Aachen University, Wendlingweg 2, 52074, Aachen, Germany. tpufe@ukaachen.de.
authors.forename: Thomas
authors.initials: T
authors.lastname: Pufe
authors.affiliation: Department of Trauma, University Hospital of Kiel, Kiel, Germany. deike.varoga@uksh-kiel.de.
authors.forename: Deike J
authors.initials: DJ
authors.lastname: Varoga
mesh_terms: D000328:Adult; D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000379:methods* / Q000639:trends; D002478:Cells, Cultured; D015331:Cohort Studies; D005260:Female; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000502:physiology; D008297:Male; D059630:Mesenchymal Stem Cells / Q000502:physiology*; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000175:diagnosis* / Q000601:surgery*; D011184:Postoperative Period