title: CD34⁺ cell content in unrelated allogeneic peripheral blood stem cell grafts transported internationally. Does the inter-laboratory variability affect comparability of graft quality data?
abstract: BACKGROUND
  Increasing numbers of unrelated hematopoietic stem cell grafts are transported internationally and evaluated concurrently in different laboratories. The graft quality assessment using the CD34(+) enumeration could be influenced by inter-laboratory variability.
  
  
  METHODS
  We retrospectively analyzed the content of CD34(+) cells in 154 consecutive collections being performed in different transplant centers during two periods (2003-2004, 2007-2010). All samples were tested twice in our own and partner laboratories. CD34(+) percentage and absolute number were compared.
  
  
  RESULTS
  The percentage and the total CD34(+) content correlated well in both observed periods (CD34(+)%: r=0.899 and r=0.922; CD34(+)×10(8)/kg: r=0.966 and r=0.880; p<0.0001). Median CD34(+) percentages obtained in our centre in comparison with other laboratories were 0.54% vs. 0.46% in 2003-2004 and 0.69% vs. 0.70% in 2007-2010 period. The degree of laboratory compliance was affected by the laboratory identity. CD34(+) percentage reported by one laboratory and CD34(+)×10(8)/kg reported by three from twelve laboratories lacked statistically significant correlation with our own data.
  
  
  CONCLUSIONS
  The study documented that results of CD34(+) cell dose assessment of the same grafts reported by different transplant centers are comparable. The graft quality data and the CD34(+) enumeration possess a limited level of inter-laboratory variability.
authors: Charles University in Prague, Faculty of Medicine in Pilsen, Czech Republic. lysak@fnplzen.cz
authors: D
authors: D
authors: Lysák
authors: L
authors: L
authors: Merglová
authors: J
authors: J
authors: Navrátilová
authors: T
authors: T
authors: Svoboda
authors: P
authors: P
authors: Jindra
authors: V
authors: V
authors: Koza
mesh_terms: D018952:Antigens, CD34 / Q000097:blood / Q000276:immunology*; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000276:immunology*; D006801:Humans; D007753:Laboratories / Q000592:standards*; D036102:Peripheral Blood Stem Cell Transplantation; D012189:Retrospective Studies; D014184:Transplantation, Homologous
chemical_list: D018952:Antigens, CD34