title: Detection of autoantibodies against platelet glycoproteins in patients with immune thrombocytopenic purpura by flow cytometric immunobead array.
abstract: BACKGROUND
  The goal of this study is to develop a flow cytometric immunobead array (FCIA) assay to detect platelet autoantibodies commonly present in bleeding patients with immune thrombocytopenic purpura (ITP).
  
  
  METHODS
  Polystyrene microbeads coated with antibodies against human platelet glycoproteins (GPs) IX (SZ1), Ib (SZ2), IIIa (SZ21), IIb (SZ22), and P-selectin (SZ51) were incubated with platelet lysate from 50 ITP patients and 86 controls. The platelet antigen-autoantibody complexes were detected by flow cytometry using an FITC-labeled antibody. The results were compared with that of a monoclonal antibody immobilization of platelet antigen (MAIPA) assay.
  
  
  RESULTS
  By FCIA, platelet autoantibodies against GPIb, GPIIb, GPIIIa, GPIX and P-selectin were detected in ITP patients. Mean fluorescent intensity values with antibodies SZ1, SZ2, SZ21, SZ22 and SZ51 were all higher in ITP patients than controls (p values<0.01). In ROC analysis, values of the area under the curve were 0.89, 0.82, 0.93, 0.94 and 0.95, respectively. In ITP diagnosis, the FCIA assay with these five antibodies had better sensitivity and accuracy than the MAIPA assay (96% vs. 44% in sensitivity; 80.9% vs. 64.7% in accuracy, p<0.01).
  
  
  CONCLUSIONS
  FCIA assays with multiple antibodies against platelet GPs may be used to improve the diagnosis of ITP in hospitals.
authors.affiliation: Key Lab of Thrombosis and Hemostasis, Jiangsu Institute of Hematology, the First Affiliated Hospital of Soochow University, Suzhou, China. heyang1963@163.com
authors.forename: Yang
authors.initials: Y
authors.lastname: He
authors.forename: Yun-xiao
authors.initials: YX
authors.lastname: Zhao
authors.forename: Ming-qing
authors.initials: MQ
authors.lastname: Zhu
authors.forename: Qingyu
authors.initials: Q
authors.lastname: Wu
authors.forename: Chang-geng
authors.initials: CG
authors.lastname: Ruan
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000936:Antigen-Antibody Complex / Q000032:analysis*; D001323:Autoantibodies / Q000032:analysis*; D001324:Autoantigens / Q000737:chemistry / Q000276:immunology*; D001792:Blood Platelets / Q000737:chemistry / Q000276:immunology*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005434:Flow Cytometry / Q000379:methods*; D005456:Fluorescent Dyes; D006801:Humans; D007118:Immunoassay; D008297:Male; D008875:Middle Aged; D010980:Platelet Membrane Glycoproteins / Q000737:chemistry / Q000276:immunology*; D011137:Polystyrenes; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000175:diagnosis* / Q000276:immunology; D012372:ROC Curve
chemical_list: D000936:Antigen-Antibody Complex; D001323:Autoantibodies; D001324:Autoantigens; D005456:Fluorescent Dyes; D010980:Platelet Membrane Glycoproteins; D011137:Polystyrenes