title: [Comparison of the immunophenotype of patients with B lineage acute lymphoblastic leukemia at diagnosis and relapse].
abstract: OBJECTIVE
  To compare the leukemia-associated immunophenotypes (LAIP) in patients with B lineage acute lymphoblastic leukemia (B-ALL) at diagnosis and relapse, and investigate its implications for minimal residual disease (MRD) detection.
  
  
  METHODS
  The immunophenotype of leukemia cells from 410 newly diagnosed and 6 relapsed patients with B-ALL were detected by four to six antibody combination, mainly CD34/CD10/CD45/CD19 of 4-color CD45/SSC gating flow cytometry (FCM).
  
  
  RESULTS
  The proportion of CD45 under-expressed or negative in relapsed patients was much higher than that in newly diagnosed patients, being 69.2% and 37.8% respectively. Immunophenotypic changes occurred in 9 relapsed patients (including 8 hematological relapse and 1 central nerves system relapse) when analyzed by paired samples analysis at diagnosis vs at relapse: 4 cases showed CD45 down-modulation and 2 up-modulation; 4 CD34 down-modulation and 2 CD10 up-modulation, while the expression of CD19 remained no change. MRD was observed in all 7 cases of hematological relapse 2 - 4 months before relapse, and the immunophenotype of MRD cells was the same as that in relapse.
  
  
  CONCLUSIONS
  A high frequency of immunophenotypic changes occurred at relapse and even in MRD before relapse, however the accuracy of MRD monitoring seemed not affected by the FCM strategy used in this investigation.
authors.affiliation: Institute of Hematology, People's Hospital of Peking University, Beijing 100044, China.
authors.forename: Yan-rong
authors.initials: YR
authors.lastname: Liu
authors.forename: Yan
authors.initials: Y
authors.lastname: Chang
authors.forename: Jia-yu
authors.initials: JY
authors.lastname: Fu
authors.forename: Yi-fei
authors.initials: YF
authors.lastname: Cheng
authors.forename: Le-ping
authors.initials: LP
authors.lastname: Zhang
authors.forename: Ling-di
authors.initials: LD
authors.lastname: Li
authors.forename: Hui
authors.initials: H
authors.lastname: Wang
authors.forename: Gui-lan
authors.initials: GL
authors.lastname: Liu
authors.forename: Shan-shan
authors.initials: SS
authors.lastname: Chen
authors.forename: Xiao-jun
authors.initials: XJ
authors.lastname: Huang
authors.forename: Dao-pei
authors.initials: DP
authors.lastname: Lu
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018941:Antigens, CD19 / Q000276:immunology; D018952:Antigens, CD34 / Q000276:immunology; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D016130:Immunophenotyping / Q000379:methods*; D017493:Leukocyte Common Antigens / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000175:diagnosis / Q000276:immunology / Q000473:pathology*; D015260:Neprilysin / Q000276:immunology; D015452:Precursor B-Cell Lymphoblastic Leukemia-Lymphoma / Q000175:diagnosis / Q000276:immunology / Q000473:pathology*; D012008:Recurrence; D055815:Young Adult
chemical_list: D018941:Antigens, CD19; D018952:Antigens, CD34; D017493:Leukocyte Common Antigens; D015260:Neprilysin