title: Differential expression of the protooncogene bcl-2 in normal and osteoarthritic human articular cartilage.
abstract: OBJECTIVE
  To investigate the expression of bcl-2 in healthy and osteoarthritic articular cartilage at the transcriptional level and at the protein level.
  
  
  METHODS
  bcl-2 mRNA was detected by reverse transcriptase/polymerase chain reaction. The expression of bcl-2 protein was studied using flow cytometry analysis with a monoclonal antibody against intracellular bcl-2 and by immunohistochemistry.
  
  
  RESULTS
  mRNA for bcl-2 was detectable in chondrocytes of both healthy and osteoarthritic cartilage. bcl-2 protein was present in the chondrocytes of the middle layer of cartilage by immunohistochemical staining. In osteoarthritis (OA), chondrocytes adjacent to cartilage defects expressed a particularly high signal intensity. Flow cytometry analysis demonstrated the presence of bcl-2 protein in virtually all chondrocytes.
  
  
  CONCLUSIONS
  Our results show that bcl-2 is expressed in healthy adult and osteoarthritic human cartilage. The increased staining of chondrocytes adjacent to osteoarthritic defects indicates a differential regulation of programmed cell death during the degenerative process in OA.
authors.affiliation: Department of Internal Medicine III, University of Vienna, Austria.
authors.forename: L
authors.initials: L
authors.lastname: Erlacher
authors.forename: R
authors.initials: R
authors.lastname: Maier
authors.forename: R
authors.initials: R
authors.lastname: Ullrich
authors.forename: H
authors.initials: H
authors.lastname: Kiener
authors.forename: M
authors.initials: M
authors.lastname: Aringer
authors.forename: M
authors.initials: M
authors.lastname: Menschik
authors.forename: W
authors.initials: W
authors.lastname: Graninger
mesh_terms: D000328:Adult; D000368:Aged; D001483:Base Sequence; D002358:Cartilage, Articular / Q000737:chemistry*; D016923:Cell Death / Q000235:genetics; D005260:Female; D005434:Flow Cytometry; D015870:Gene Expression; D006801:Humans; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D010003:Osteoarthritis / Q000235:genetics* / Q000473:pathology; D016133:Polymerase Chain Reaction; D011518:Proto-Oncogene Proteins / Q000032:analysis*; D019253:Proto-Oncogene Proteins c-bcl-2; D011519:Proto-Oncogenes / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis*
chemical_list: D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger