title: Impact of cryopreservation on B cell chronic lymphocytic leukaemia phenotype.
abstract: OBJECTIVE
  Freezing is a practical approach for cell preservation for retrospective studies. The aim of this work was to check the cryopreservation impact on B cell chronic lymphocytic leukaemia phenotype.
  
  
  METHODS
  Blood samples from 15 CLL patients were analyzed freshly and after freezing at -196 degrees C, without separation, and thawing. Results were compared by Student's paired t-test.
  
  
  RESULTS
  The phenotype of fresh CLL cells was as follows: CD19+, CD5+, faint CD20, CD23+/-, weak CD22 and sIg, CD37+, HLA-DR+, FMC7-. After cryopreservation, the percentage of CD5 and CD23 positive cells decreased, whereas HLA-DR positive cells increased moderately. The CLL Matutes's score was modified in 6 cases out of 15 (40%).
  
  
  CONCLUSIONS
  Cryopreservation modifies B cell chronic lymphocytic leukaemia phenotype, by decreasing CD5 and CD23 expression.
authors.affiliation: Université Catholique de Louvain, University Hospital, Immunohaematology Laboratory, 1200, Brussels, Belgium. deneys@sang.ucl.ac.be
authors.forename: V
authors.initials: V
authors.lastname: Deneys
authors.forename: V
authors.initials: V
authors.lastname: Thiry
authors.forename: N
authors.initials: N
authors.lastname: Hougardy
authors.forename: A M
authors.initials: AM
authors.lastname: Mazzon
authors.forename: P
authors.initials: P
authors.lastname: Leveugle
authors.forename: M
authors.initials: M
authors.lastname: De Bruyère
mesh_terms: D000328:Adult; D015703:Antigens, CD / Q000097:blood; D001402:B-Lymphocytes / Q000276:immunology; D001793:Blood Preservation; D018956:CD5 Antigens / Q000097:blood; D015925:Cryopreservation; D005069:Evaluation Studies as Topic; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000097:blood; D006801:Humans; D007145:Immunoglobulin kappa-Chains / Q000097:blood; D007146:Immunoglobulin lambda-Chains / Q000097:blood; D016130:Immunophenotyping; D015448:Leukemia, B-Cell / Q000097:blood* / Q000276:immunology*; D017455:Receptors, IgE / Q000097:blood
chemical_list: D015703:Antigens, CD; D018956:CD5 Antigens; D006684:HLA-DR Antigens; D007145:Immunoglobulin kappa-Chains; D007146:Immunoglobulin lambda-Chains; D017455:Receptors, IgE