title: Ficoll-separated mononuclear cells from sepsis patients are contaminated with granulocytes.
abstract: OBJECTIVE
  To determine the cell content and purity of Ficoll-separated peripheral blood mononuclear cells and granulocyte isolates in sepsis patients compared to healthy controls.
  
  
  METHODS
  Prospective study in the adult and pediatric intensive care departments of the Erasmus University Medical Center in the Netherlands.
  
  
  METHODS
  Three sepsis patients (two adults, one child) and four healthy controls.
  
  
  RESULTS
  Blood leukocytes were separated by Ficoll into an interface and a bottom fraction. The cell content and purity was analyzed by cytospin and flow-cytometric immunofluorescence. In sepsis patients, the interface consisted of 11-52% mononuclear cells only, due to high contamination with granulocytes (48-89%). This was in contrast to a high proportion of mononuclear cells (88-100%) in healthy controls. The bottom fraction showed a cell purity of >or=92% polymorphonuclear granulocytes in sepsis patients as well as in healthy controls.
  
  
  CONCLUSIONS
  Ficoll-separated leukocytes of sepsis patients are not suitable for studying mononuclear cells but can be used for studying granulocytes with high purity. The mononuclear cell fraction is highly contaminated with granulocytes. Additional separation techniques are necessary to obtain a pure cell fraction.
authors.affiliation: Department of Pediatric Endocrinology, Office sp 1536, Erasmus MC, PO Box 2060, 3000 CB Rotterdam, The Netherlands. e.l.t.vandenakker@erasmusmc.nl
authors.forename: Erica L T
authors.initials: EL
authors.lastname: van den Akker
authors.forename: Carla C
authors.initials: CC
authors.lastname: Baan
authors.forename: Bart
authors.initials: B
authors.lastname: van den Berg
authors.forename: Henk
authors.initials: H
authors.lastname: Russcher
authors.forename: Koen
authors.initials: K
authors.lastname: Joosten
authors.forename: Anita C S
authors.initials: AC
authors.lastname: Hokken-Koelega
authors.forename: Steven W J
authors.initials: SW
authors.lastname: Lamberts
authors.forename: Jan W
authors.initials: JW
authors.lastname: Koper
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D002469:Cell Separation / Q000379:methods*; D002499:Centrifugation, Density Gradient / Q000379:methods*; D002648:Child; D005362:Ficoll; D006098:Granulocytes / Q000737:chemistry*; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000737:chemistry*; D008297:Male; D015166:Monitoring, Immunologic; D015203:Reproducibility of Results; D018805:Sepsis / Q000276:immunology*
chemical_list: D005362:Ficoll