Detection and differentiation of platelet-specific antibodies by flow cytometry: the bead-mediated platelet assay.
BACKGROUND
Platelet-reactive antibodies cause a number of clinical disorders. The detection and differentiation of these antibodies are prerequisites for the adequate treatment of these disorders. The bead-mediated platelet assay described here enables the detection and differentiation of platelet-bound antibodies by the use of flow cytometry.


METHODS
The bead-mediated platelet assay is based on the isolation of human platelet glycoproteins by using flow cytometric standardization beads after the incubation of typed platelets with human sera. The specificity and sensitivity of this assay were tested with five sera, each containing a known platelet-reactive antibody. The monoclonal antibody-specific immobilization of platelet antigens assay was used as a reference test.


RESULTS
The bead-mediated platelet assay was able to determine the glycoprotein specificity of the antibody without cross-reactions in every case. In serial dilution tests, the bead-mediated platelet assay was able to detect the antibodies at higher dilutions than the monoclonal antibody-specific immobilization of platelet antigen assay. Total test time was 3.5 hours.


CONCLUSIONS
The bead-mediated platelet assay is a fast and reliable method for the detection and differentiation of platelet-reactive antibodies.
Helmberg
W
W
Department of Transfusion Medicine, University Hospital Graz, Austria.
Fölsch
B
B
Wagner
T
T
Lanzer
G
G
D000911:Antibodies, Monoclonal / Q000032:analysis; D016824:Antigens, Human Platelet / Q000276:immunology*; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D007518:Isoantibodies / Q000032:analysis* / Q000276:immunology; D008863:Microspheres; D013997:Time Factors
D000911:Antibodies, Monoclonal; D016824:Antigens, Human Platelet; D007518:Isoantibodies