title: Initial cord blood unit volume affects mononuclear cell and CD34+ cell-processing efficiency in a non-linear fashion.
abstract: OBJECTIVE
  Umbilical cord blood (UCB) is a source of hematopoietic stem cells that initially was used exclusively for the hematopoietic reconstitution of pediatric patients. It is now suggested for use for adults as well, a fact that increases the pressure to obtain units with high cellularity. Therefore, the optimization of UCB processing is a priority.
  
  
  METHODS
  The present study focused on parameters influencing total nucleated cell (TNC), mononucleated cell (MNC) and CD34+ cell (CD34C) recovery after routine volume reduction of 1553 UCB units using hydroxyethyl starch-induced sedimentation with an automated device, under routine laboratory conditions.
  
  
  RESULTS
  We show that the unit volume rather than the TNC count significantly affects TNC, MNC and CD34C processing efficiency (PEf), and this in a non-linear fashion: when units were sampled according to the collection volume, including pre-loaded anticoagulant (gross volume), PEf increased up to a unit volume of 110-150 mL and decreased thereafter. Thus units with initial gross volumes < 90 mL and > 170 mL similarly exhibited a poor PEf.
  
  
  CONCLUSIONS
  These data identify unit gross volume as a major parameter influencing PEf and suggest that fractionation of large units should be contemplated only when the resulting volume of split units is > 90 mL.
authors.affiliation: Basel University Hospital ,  Basel ,  Switzerland.
authors.forename: Sandrine
authors.initials: S
authors.lastname: Meyer-Monard
authors.forename: André
authors.initials: A
authors.lastname: Tichelli
authors.forename: Carolyn
authors.initials: C
authors.lastname: Troeger
authors.forename: Caroline
authors.initials: C
authors.lastname: Arber
authors.forename: Grazia Nicoloso
authors.initials: GN
authors.lastname: de Faveri
authors.forename: Alois
authors.initials: A
authors.lastname: Gratwohl
authors.forename: Eddy
authors.initials: E
authors.lastname: Roosnek
authors.forename: Daniel
authors.initials: D
authors.lastname: Surbek
authors.forename: Yves
authors.initials: Y
authors.lastname: Chalandon
authors.forename: Olivier
authors.initials: O
authors.lastname: Irion
authors.forename: Damiano
authors.initials: D
authors.lastname: Castelli
authors.forename: Jakob
authors.initials: J
authors.lastname: Passweg
authors.forename: Vincent
authors.initials: V
authors.lastname: Kindler
mesh_terms: D018952:Antigens, CD34 / Q000276:immunology; D001799:Blood Sedimentation; D018929:Cell Culture Techniques / Q000379:methods*; D005312:Fetal Blood / Q000166:cytology*; D006412:Hematopoietic Stem Cells / Q000166:cytology*; D006801:Humans; D006895:Hydroxyethyl Starch Derivatives / Q000737:chemistry; D007963:Leukocytes, Mononuclear / Q000166:cytology*; D013601:T-Lymphocytes / Q000166:cytology / Q000276:immunology
chemical_list: D018952:Antigens, CD34; D006895:Hydroxyethyl Starch Derivatives