title: Validation of different replication markers for the detection of beta-cell proliferation in human pancreatic tissue.
abstract: BACKGROUND
  Beta-cell-regeneration is considered as a future option for the therapy of diabetes, but the detection of beta-cell replication in human pancreas is still challenging. Therefore, the expression of Ki67, PCNA and MCM-7 in human pancreatic tissue was quantified in order to validate their use as beta-cell replication markers.
  
  
  METHODS
  Human pancreatic tissue samples were stained for Ki67, PCNA, MCM7, insulin and nuclei, and the expression of replication markers was quantified. Co-expression of the markers was assessed by four-colour fluorescence-staining.
  
  
  RESULTS
  All three markers could be detected in endocrine and exocrine tissue. There was a significant correlation between the expression frequencies of all three markers in the exocrine tissue (r>0.49, respectively) and in beta-cells (r>0.95, respectively). A subset of beta-cells with differential expression of the three replication markers was identified. Quantitative analyses revealed that only 36-55% of all exocrine cells expressed two markers at the same time.
  
  
  CONCLUSIONS
  The expression of Ki67, MCM-7 and PCNA in adult human pancreas is highly correlated, but the labelling of individual cells differs between the markers. The analysis of a combination of markers, preferably MCM7 and Ki67, appears to yield the most reliable results for the determination of beta-cell replication and may allow for a differentiation of cell cycle stages.
authors.affiliation: Department of Medicine I, St. Josef-Hospital, Ruhr-University Bochum, Gudrunstrasse 56, Bochum D-44791, Germany.
authors.forename: Christina U
authors.initials: CU
authors.lastname: Köhler
authors.forename: Alexander
authors.initials: A
authors.lastname: Kreuter
authors.forename: Martha C
authors.initials: MC
authors.lastname: Rozynkowski
authors.forename: Tim
authors.initials: T
authors.lastname: Rahmel
authors.forename: Waldemar
authors.initials: W
authors.lastname: Uhl
authors.forename: Andrea
authors.initials: A
authors.lastname: Tannapfel
authors.forename: Wolfgang E
authors.initials: WE
authors.lastname: Schmidt
authors.forename: Juris J
authors.initials: JJ
authors.lastname: Meier
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000378:metabolism*; D049109:Cell Proliferation; D006801:Humans; D007150:Immunohistochemistry; D007515:Islets of Langerhans / Q000166:cytology* / Q000378:metabolism; D008875:Middle Aged
chemical_list: D015415:Biomarkers