title: Residual WBC subsets in filtered prestorage RBCs.
abstract: BACKGROUND
  New-generation RBC filters reduce WBC concentrations by 4 to 5 logs and may prevent or decrease transfusion complications such as HLA alloimmunization, nonhemolytic febrile reaction, and transfusion-transmitted infections. The residual level of WBC subsets may influence efficacy of WBC reduction for preventing various complications. This study analyzed subsets of residual WBCs in WBC-reduced RBC components prepared for a large, multicenter prospective study.
  
  
  METHODS
  The Viral Activation Transfusion Study (VATS) assessed the impact of WBC reduction in HIV-1-infected patients undergoing RBC transfusion. WBC-reduced RBC from 11 clinical sites with variable filtration practices were sorted into "low,""middle," and "high" groups based on residual WBC concentration. Subsets were isolated from units by immunocapture (anti-CD4-, anti-CD8-, anti-CD15-, and anti-CD19-coated magnetic beads) and quantified by PCR amplification.
  
  
  RESULTS
  After validation studies confirming test methodology, 105 VATS WBC-reduced RBC samples were analyzed. Concentrations of subsets in low and middle residual WBC groups were very low in contrast to relatively high concentrations in the high group. Although highly significant differences were identified between the middle and high groups for total WBCs and all subsets, no single subset predominated.
  
  
  CONCLUSIONS
  These results suggest that overall efficacy of WBC filtration correlates with removal of WBC subsets.
authors.affiliation: Department of Medicine, Neonatal Intensive Care Unit, Fukushima Medical University, Japan.
authors.forename: Hiromichi
authors.initials: H
authors.lastname: Ariga
authors.forename: Tzong-Hae
authors.initials: TH
authors.lastname: Lee
authors.forename: Megan E
authors.initials: ME
authors.lastname: Laycock
authors.forename: Beth A
authors.initials: BA
authors.lastname: Mohr
authors.forename: Leslie A
authors.initials: LA
authors.lastname: Kalish
authors.forename: Roslyn
authors.initials: R
authors.lastname: Yomtovian
authors.forename: Terry
authors.initials: T
authors.lastname: Gernsheimer
authors.forename: Michael P
authors.initials: MP
authors.lastname: Busch
mesh_terms: D001781:Blood Component Removal; D001793:Blood Preservation; D004311:Double-Blind Method; D004912:Erythrocytes; D005374:Filtration; D006801:Humans; D007962:Leukocytes; D016256:Lewis X Antigen / Q000032:analysis
chemical_list: D016256:Lewis X Antigen