Abstract:

Objective To establish quantitative monoclonal antibody-specific immobilization of platelet（PLT） antigen （MAIPA） assay for human PLT antigen（HPA）-1a,HPA-3a and HPA-5b antibodies.Methods MAIPA assay was applied on serial dilutions of standard or reference reagents containing antibodies against HPA-1a,HPA-3a and HPA-5b. Optimal experimental parameters were determined,and standard curves were constructed with linear regression. The sensitivity,specificity and reproducibility of the assay were evaluated. Results The optimal reagents and conditions for MAIPA assay were decided. The determination ranges were 0-4 IU,0-20 AU and 0-20 AU,and accuracies（recovery rates）were 96.20%-103.10%,97.90%-103.10% and 100.20%-106.10%. The within-run precisions [coefficients of variation （CV）] for HPA-1a,HPA-3a and HPA-5b antibodies were 1.3%-3.6%,2.7%-5.2% and 4.7%-5.3%. The between-run precisions （CV） were 4.0%-5.6%,4.4%-5.9% and 3.2%-6.3%. There was no positivity for anti-A,anti-B,anti-I and anti-P humanized antibodies with good specificities.Conclusions The established quantitative MAIPA assay for HPA-1a,HPA-3a and HPA-5b antibodies has good sensitivity,specificity,accuracy and precision. It plays a role in the clinical diagnosis of alloimmunization disease caused by HPA antibodies and safe transfusion of PLT.

Key words: Human platelet antigen, Monoclonal antibody-specific immobilization of platelet antigen, Quantitation, Standard system