Report on the 16th international society of blood transfusion platelet immunology workshop.

Background The main aims of the 16th ISBT Platelet Immunology workshop were as follows: (i) to test the ability of the laboratories in the identification of platelet alloantibodies, (ii) to compare the detection of HPA-1a alloantibodies in serum and plasma, (iii) to quantify HPA-1a alloantibodies, (iv) to measure platelet-bound HPA-1a alloantibodies in lysates, (v) to evaluate a new bead-based assay for anti- HPA-1a and anti- HPA-1b detection, (vi) to evaluate the efficiency of a human monoclonal antibody for HPA-5a phenotyping and (vii) to test the ability to genotype for HPA-1, HPA-2, HPA-3, HPA-4, HPA-5, HPA-6, HPA-9, HPA-12w, HPA-13w and HPA-15. Materials and methods Seven exercises were developed to encompass the aims of this workshop. All materials and procedures were distributed for 34 laboratories from 20 countries. Results The platelet alloantibodies identification exercise presented good results compared with previous workshops. Comparison between serum and plasma in titration study showed comparable results for HPA-1a and HPA-5b alloantibodies. For the quantitative determination of HPA-1a alloantibodies, most of the laboratories could reliably assign a similar concentration. It was also possible to identify bound anti- HPA-1a alloantibodies in cell lysates within 2 weeks. The bead assay demonstrated good reproducibility between laboratories although some anti- HPA-1a samples remain an issue. Phenotyping of HPA-5b showed high false-negative error (6%). DNA typing presented excellent results, demonstrating that DNA tests for HPA are very well established in all laboratories. Conclusions This workshop presented high complexity exercises with very good results achieved in most of the exercises and approximately 100% consensus among the participants. [ABSTRACT FROM AUTHOR]