U J Sachs1, V Kiefel, H Kroll, G Bein, S Santoso. 1. Institute for Clinical Immunology and Transfusion Medicine, Justus Liebig University, Giessen, Germany. ulrich.sachs@med.uni-giessen.de
Abstract
BACKGROUND AND OBJECTIVES: The aim of the 15th ISBT Platelet Immunology Workshop was to evaluate the detection of free platelet-reactive autoantibodies from ITP patients by the use of a standardized MAIPA protocol, to compare sensitivity and specificity of antibody detection for anti-HPA-1a and serologically difficult-to-assess antibodies against HPA-3, to identify whether anti-HPA-1a titration results can be compared between laboratories, and to evaluate HPA genotyping methods. MATERIALS AND METHODS: Workshop materials were shipped from the organizing laboratory in Giessen, Germany. Thirty laboratories from 19 countries participated. RESULTS: Results for the detection of autoantibodies differed greatly between the laboratories and no consensus was reached for one of the two sera. Detection and titration of antibodies against HPA-1a, in contrast, gave largely congruent results. Serologically difficult-to-assess antibodies recognizing HPA-3a and HPA-3b were not detected by many laboratories. For genotyping, good agreement was achieved. CONCLUSIONS: Detection of HPA-1a antibodies, titration of anti-HPA-1a, and HPA genotyping are well performed in most participating laboratories. The workshop has identified two specific areas with room and need for improvement: the detection of autoantibodies and the detection of HPA-3 alloantibodies. Recommendations of the Working Party on techniques that can help to overcome these problems are desirable.
BACKGROUND AND OBJECTIVES: The aim of the 15th ISBT Platelet Immunology Workshop was to evaluate the detection of free platelet-reactive autoantibodies from ITP patients by the use of a standardized MAIPA protocol, to compare sensitivity and specificity of antibody detection for anti-HPA-1a and serologically difficult-to-assess antibodies against HPA-3, to identify whether anti-HPA-1a titration results can be compared between laboratories, and to evaluate HPA genotyping methods. MATERIALS AND METHODS: Workshop materials were shipped from the organizing laboratory in Giessen, Germany. Thirty laboratories from 19 countries participated. RESULTS: Results for the detection of autoantibodies differed greatly between the laboratories and no consensus was reached for one of the two sera. Detection and titration of antibodies against HPA-1a, in contrast, gave largely congruent results. Serologically difficult-to-assess antibodies recognizing HPA-3a and HPA-3b were not detected by many laboratories. For genotyping, good agreement was achieved. CONCLUSIONS: Detection of HPA-1a antibodies, titration of anti-HPA-1a, and HPA genotyping are well performed in most participating laboratories. The workshop has identified two specific areas with room and need for improvement: the detection of autoantibodies and the detection of HPA-3 alloantibodies. Recommendations of the Working Party on techniques that can help to overcome these problems are desirable.