title: Exploring the possibility of DNA ploidy measurements in tissue sections using liver as a model.
abstract: OBJECTIVE
  To evaluate DNA image cytometry (ICM) in tissue sections, human and rat liver was used as a model. These tissues have distinct DNA ploidy histograms of mainly diploid (human) and predominantly tetraploid (rat) plus octaploid nuclei.
  
  
  METHODS
  Section thickness varied from 4 to 12 microns in rat liver and 4 to 10 microns in human liver, in steps of 2 microns. The measurements were made using a commercially available ICM system, strictly following a measurement protocol.
  
  
  RESULTS
  Four-micrometer-thick sections gave very broad histograms. Six-micrometer-thick sections gave better results, but with increasing DNA PLOIDY (> 4c), modal peaks were broad and increasingly shifted to the left. Sections of 8-10 microns gave linear results of the 2c, 4c and 8c peaks and also the narrowest peaks. The 12-micron sections of rat liver were more difficult to measure, and the results were not improved.
  
  
  CONCLUSIONS
  The 8-micron sections gave the best results and were easiest to measure. These results are promising, but since liver is a fairly simple model, further studies are required to elucidate whether DNA ploidy measurements can be performed reliably on tissue sections of human tumors.
authors.affiliation: St. Vincent's Department of Anatomic Pathology, Wangaratta Service, University of Melbourne, Australia.
authors.forename: R A
authors.initials: RA
authors.lastname: Williams
authors.forename: J P
authors.initials: JP
authors.lastname: Baak
authors.forename: G A
authors.initials: GA
authors.lastname: Meijer
authors.forename: I G
authors.initials: IG
authors.lastname: Charlton
mesh_terms: D000818:Animals; D002467:Cell Nucleus; D004247:DNA / Q000032:analysis*; D006801:Humans; D019044:Image Cytometry / Q000379:methods*; D008099:Liver / Q000737:chemistry*; D011003:Ploidies; D051381:Rats
chemical_list: D004247:DNA