title: Determination of differential cell counts in feline bone marrow by use of flow cytometry.
abstract: OBJECTIVE
  To evaluate the potential usefulness of 2 flow cytometric methods for determination of differential cell counts in feline bone marrow.
  
  
  METHODS
  10 bone marrow specimens from client-owned cats.
  
  
  METHODS
  Bone marrow specimens were stained with 3,3'-dihexyloxacarbocyanine iodide (DiOC6) and evaluated by use of flow cytometry. Differential counts were also determined by analysis of scatterplots of forward-angle versus side-angle light scatter of unstained specimens, obtained by use of flow cytometry (scatterplot method). Results of both flow cytometric methods were compared with differential cell counts determined by manually counting 1,000 cells on slides of Wright-stained smears.
  
  
  RESULTS
  Staining with DiOC6 resulted in identification of mature and immature erythroid and myeloid cells and lymphocytes. Use of the scatterplot method resulted in identification of mature and immature erythroid and myeloid cells and metamyelocytes. However, to identify lymphocytes by use of the scatterplot method, bone marrow specimens were first labeled with an anti-major histocompatability class-II antibody. Comparison of results of the scatterplot method with manual counts yielded higher correlation coefficients and more similar mean values than did comparison of results of the DiOC6 method.
  
  
  CONCLUSIONS
  The scatterplot method provided more accurate and precise results than the DiOC6 method for determination of bone marrow differential cell counts in cats by use of flow cytometry. When combined with fluorescent labeling of lymphocytes, the scatterplot method has potential to provide rapid semiquantitative assessment of bone marrow differential cell counts in cats.
authors.affiliation: Department of Veterinary PathoBiology, College of Veterinary Medicine, University of Minnesota, St Paul 55108, USA.
authors.forename: D J
authors.initials: DJ
authors.lastname: Weiss
mesh_terms: D000818:Animals; D001772:Blood Cell Count / Q000662:veterinary; D001854:Bone Marrow Cells / Q000166:cytology*; D002232:Carbocyanines; D002371:Cat Diseases / Q000175:diagnosis / Q000473:pathology*; D002415:Cats; D005434:Flow Cytometry / Q000379:methods / Q000662:veterinary*; D005452:Fluoresceins; D005456:Fluorescent Dyes; D006402:Hematologic Diseases / Q000175:diagnosis / Q000473:pathology / Q000662:veterinary*
chemical_list: D002232:Carbocyanines; D005452:Fluoresceins; D005456:Fluorescent Dyes; C007392:3,3'-dihexyl-2,2'-oxacarbocyanine; C037631:2',7'-dichlorofluorescein