title: Evaluation of a new prestorage leukoreduction filter for red blood cell units.
abstract: OBJECTIVE
  Prestorage leukoreduction offers a variety of potential benefits and is becoming more commonly practiced. The LeukoNet prestorage leukoreduction filtration system is intended for leukoreduction of red blood cells and uses a vent to allow automatic drainage of red cells from the filter.
  
  
  METHODS
  We studied the functional characteristics and the in-vivo and in-vitro properties of leukoreduced AS-1 Red Blood Cells prepared with this new system. Units of AS-1 Red Blood Cells were filtered at 4 degrees C through the LeukoNet filter 24-48 h after collection and stored under usual conditions for 42 days. Residual leukocytes were enumerated using a Nageotte chamber or with a polymerase chain reaction (PCR) technique. In the clinical trial (phase one), 21 donors had units stored with and without leukoreduction for 42 days; biochemical assays were done before and after storage, and 51Cr/99mTc red cell recovery studies at the end of the storage period.
  
  
  RESULTS
  Leukocyte content after filtration was 3.2 +/- 2.6 x 10(4)/unit (n = 21), and all units had < 1 x 10(5) leukocytes (median: 3.8 x 10(4)). In-vivo paired studies showed no difference in 24-hour recovery (control: 82.1 +/- 5.8%; test: 82.9 +/- 6.0%). Hemolysis was halved with leuko-reduction (0.59 +/- 0.30 vs. 0.29 +/- 0.11%; p < 0.05), and glucose consumption was reduced by 5% compared to control units (p = < 0.05). Other biochemical parameters showed no differences. In the practical trial (phase two), filtration time was 41 +/- 23 min. With a residual leukocyte content of 6.6 +/- 4.9 x 10(4)/unit and 14 +/- 3% red cell loss (n = 84). Six additional units underwent leukocyte enumeration by PCR and had 2.6 +/- 1.1 x 10(4) residual leukocytes.
  
  
  CONCLUSIONS
  Under the conditions studied, the LeukoNet leukoreduction filtration system produces about 4-5 log10 leukocyte content reduction.
authors.affiliation: Department of Pathology, Dartmouth-Hitchcock Medical Center, Lebanon, N.H. 03756, USA.
authors.forename: J P
authors.initials: JP
authors.lastname: AuBuchon
authors.forename: M D
authors.initials: MD
authors.lastname: Elfath
authors.forename: M A
authors.initials: MA
authors.lastname: Popovsky
authors.forename: R R
authors.initials: RR
authors.lastname: Stromberg
authors.forename: C
authors.initials: C
authors.lastname: Pickard
authors.forename: L
authors.initials: L
authors.lastname: Herschel
authors.forename: P
authors.initials: P
authors.lastname: Whitley
authors.forename: D
authors.initials: D
authors.lastname: McNeil
authors.forename: N
authors.initials: N
authors.lastname: Arnold
authors.forename: J L
authors.initials: JL
authors.lastname: O'Connor
mesh_terms: D017707:Erythrocyte Transfusion; D005374:Filtration / Q000295:instrumentation*; D006801:Humans; D007937:Leukapheresis / Q000295:instrumentation*