title: Viability of umbilical cord blood mononuclear cell subsets until 96 hours after collection.
abstract: BACKGROUND
  Umbilical cord blood (UCB) is a good source of hematopoietic stem cells for transplantation and cell therapy. In 2006, the Brazilian Public Network of Cord Blood Banks was founded; however, because our country is large, logistic problems could hamper the collection of numerous samples. Our aim was to evaluate the viability of several UCB cell subsets until 96 hours after collection, to examine whether this delay would be acceptable for processing and freezing the samples.
  
  
  METHODS
  Two experiments were performed: in the first one, volume reduction of the UCB units was carried out before analysis. In the second one, analysis was carried out with no previous manipulation. Samples were stored at room temperature and one aliquot was taken daily for analysis. We examined CD34+ cell, B-cell precursor, mature B and T lymphocyte, monocyte, granulocyte, and mesenchymal stem cell (MSCs) concentrations.
  
  
  RESULTS
  Thirty-six UCB units were analyzed. CD34+ cells and mature T lymphocytes increased (viability 99%). Mature B lymphocytes and MSCs decreased, maintaining viability. Granulocytes decreased with loss of viability. Monocytes and immature B lymphocytes remained stable. Clonogenic assays showed a decrease in colony-forming unit (CFU) number in UCB units stored for 96 hours.
  
  
  CONCLUSIONS
  UCB manipulation did not influence cell viability. All cell subsets remained viable until 96 hours after collection. CD34+ cells and T lymphocytes increased, probably due to the loss of other subsets. CFU growth during the period analyzed and confirmed stem cell functionality, despite the decrease at 96 hours. Results demonstrated that UCB units could probably be processed up to 96 hours after collection.
authors: Flow Cytometry Laboratory and Public Umbilical Cord Blood Bank of Haematology Hemotherapy Center, INCT do Sangue, Department of Internal Medicine, Faculty of Medical Sciences, University of Campinas, Campinas, Brazil.
authors: Fernanda G
authors: FG
authors: Pereira-Cunha
authors: Adriana S S
authors: AS
authors: Duarte
authors: Fernando F
authors: FF
authors: Costa
authors: Sara T O
authors: ST
authors: Saad
authors: Irene
authors: I
authors: Lorand-Metze
authors: Angela C M
authors: AC
authors: Luzo
mesh_terms: D018952:Antigens, CD34 / Q000378:metabolism; D001402:B-Lymphocytes / Q000166:cytology; D001771:Blood Banks; D001938:Brazil; D002470:Cell Survival / Q000502:physiology*; D015925:Cryopreservation; D005312:Fetal Blood / Q000166:cytology*; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000166:cytology; D006801:Humans; D007963:Leukocytes, Mononuclear / Q000166:cytology*; D013601:T-Lymphocytes / Q000166:cytology
chemical_list: D018952:Antigens, CD34