Multilaboratory Evaluation of Serum Analysis for HLA Antibody and Crossmatch Reactivity by Lymphocytotoxicity Methods

Abstract Context.—This report presents results of the serum antibody analysis and crossmatch challenges in the proficiency testing program for histocompatibility testing jointly sponsored by the American Society for Histocompatibility and Immunogenetics and the College of American Pathologists. Objective.—To obtain information about consensus rates among participating laboratories that reported antibody screening and crossmatch results by direct complement-dependent lymphocytotoxicity (CDC) and/or anti-human globulin (AHG)–augmentation methods. Design.—We analyzed responses from approximately 165 laboratories participating in 32 surveys during 1993–2000. Most of the testing was done by CDC methods, but increasing proportions of laboratories are using AHG augmentation of these techniques; almost one half of the serum screenings and crossmatches were done by AHG. Results.—A total of 40 serum specimens were screened to determine the percent panel-reactive antibody (PRA) and identify HLA-specific antibodies. ...