title: Quantifying loss of CD34+ cells collected by apheresis after processing for freezing and post-thaw.
abstract: BACKGROUND
  CD34(+) cells collected for autologous bone marrow transplantation (BMT) are usually quantified in the apheresis product after collection, but the necessity to repeat these measures post-thaw is controversial.
  
  
  METHODS
  We examined the loss of CD34(+) cells after collection, preparation for freezing and post-thaw in apheresis products collected for BMT.
  
  
  RESULTS
  Median number of CD34(+) cells collected per unit was 1.61×10(6)/kg, viability: 97-100%. This number decreased to 1.38×10(6)/kg, viability: 96-100% before freezing and was 1.17×10(6)/kg post-thaw. Viability decreased to 86-98%. The relative loss of viable PBHPC showed an inverse correlation with the ratio "CD34(+) cells/total nucleated cells" (r=-0.45; p=<0.0005). This relative loss was largest in patients with Hodgkin's lymphoma.
  
  
  CONCLUSIONS
  Cryopreservation and thawing of PBHPCs in leukapheresis products provokes a small but significant stem cell loss. So, quantification of viable CD34(+) cells post-thaw is important, especially in poorly mobilizing patients. Besides, the ratio "CD34(+) cells/total nucleated cells" after leukapheresis is an important parameter for prediction of neutrophil recovery after BMT.
authors: Hematology and Hemotherapy Center, State University of Campinas, Rua Carlos Chagas 480, Campinas, SP, Brazil.
authors: Mariana V
authors: MV
authors: Castelhano
authors: Suiellen C
authors: SC
authors: Reis-Alves
authors: Afonso C
authors: AC
authors: Vigorito
authors: Felipe F
authors: FF
authors: Rocha
authors: Fernanda G
authors: FG
authors: Pereira-Cunha
authors: Carmino A
authors: CA
authors: De Souza
authors: Irene
authors: I
authors: Lorand-Metze
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism*; D001854:Bone Marrow Cells / Q000378:metabolism / Q000473:pathology; D016026:Bone Marrow Transplantation; D002470:Cell Survival; D015925:Cryopreservation; D005260:Female; D006801:Humans; D007937:Leukapheresis; D008228:Lymphoma, Non-Hodgkin / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D008297:Male; D009101:Multiple Myeloma / Q000378:metabolism / Q000473:pathology / Q000628:therapy; D013997:Time Factors; D014182:Transplantation, Autologous
chemical_list: D018952:Antigens, CD34