title: Ploidy analysis on Wilms' tumour touch imprints using ethidium bromide and automated image analysis integrated confocal laser scanning microscopy.
abstract: Although image analysis (IA) is increasingly being used to quantitate nuclear DNA, comparative data between fluorescence methods of IA and flow cytometry (FCM) is limited. In this study fluorescence IA was compared with FCM data in a series of Wilms' tumour touch preparations. Airdried touch imprints that had previously been Giemsa stained were restained with ethidium bromide. Confocal fluorescence images were obtained with a confocal laser scanning microscope and assessed by a fully automated IA package. Data was collected from 400 nuclei per imprint. The resulting DNA histograms were analysed and ploidy status and DNA indices determined using standard criteria. Results were compared with those derived from FCM analysis of nuclear suspensions. Ten of twelve tumours were concordant by both techniques. However in two cases assessed as diploid by FCM, IA identified aneuploidy. Excellent correlation between DNA indices as assessed by both techniques was observed (r = 0.987). In the three cases for which both unstained and Giemsa stained touch imprints were available for IA, the histogram configurations did not differ significantly. Fluorescence IA is an accurate and sensitive technique for DNA quantitation, which appears at least comparable to FCM assessment and which has a number of important advantages.
authors.affiliation: Department of Medicine, University of Liverpool, UK.
authors.forename: S J
authors.initials: SJ
authors.lastname: Hayes
authors.forename: S A
authors.initials: SA
authors.lastname: Hinchliffe
authors.forename: J D
authors.initials: JD
authors.lastname: Pope
authors.forename: P
authors.initials: P
authors.lastname: Eccles
authors.forename: M M
authors.initials: MM
authors.lastname: Khine
authors.forename: R O
authors.initials: RO
authors.lastname: Kaschula
authors.forename: A
authors.initials: A
authors.lastname: Sampedro
authors.forename: D
authors.initials: D
authors.lastname: van Velzen
mesh_terms: D002675:Child, Preschool; D004247:DNA / Q000032:analysis*; D004996:Ethidium; D005434:Flow Cytometry; D006801:Humans; D019044:Image Cytometry; D007680:Kidney Neoplasms / Q000235:genetics*; D018613:Microscopy, Confocal; D011003:Ploidies; D009396:Wilms Tumor / Q000235:genetics*
chemical_list: D004247:DNA; D004996:Ethidium