P004: 2014 XM-ONE PROFICIENCY TESTING (PT) PROGRAM UPDATE

Abstract

Aim These PT surveys are designed to emulate clinical testing for antibodies against Non-HLA Ags expressed on endothelial progenitor cells (EPC) as well as optional testing for antibodies against HLA Ags present on T and B lymphocytes, simultaneously in the same tube or well (3:1). This year more than seventeen laboratories have participated in these exercises. Four international sites have joined the national (USA) laboratories. Methods Since inception in 2011, the exchange includes 2 whole blood cells as targets and 5 analytes. All sites used similar negative and positive controls and their Clinical Interpretations (CI) are compared to the consensus. Of the 17 centers participating in the 2014-I survey, 3/17 requested to be considered as Educational Participants (EP), 12/17 reported IgG & IgM results, while 2/17 reported IgG results only. Nine of the 17 sites reported 3:1 results. In the evaluation, only the positive or negative CI was taken into consideration. Nevertheless, all reported results were meticulously examined to explain the posted CI. In the 2014-I survey, one weak analyte was posted as an Educational Challenge (EC). Results All 14/17 sites graded received a successful participation (SP) recommendation. Those requesting their results to be consider as EP only were not graded or considered in the consensus analysis. Ten of the fourteen sites had perfect scores when reporting for IgG and/or IgM in the EPC category. The EPC IgG results from three different sites missed consensus for one analyte each, one due to a technical switch that affected all other categories. A fourth site missed two analytes. The EPC IgM was only missed by 1/14 sites in two analyte. On the T and B cell categories, 4/9 sites missed one IgG or IgM and 2/9 sites missed one IgG analyte consensus, respectively. The EC analyte (2014-I-03) reached a 60% borderline positive consensus for IgG when tested against B013 EPC target cells. Conclusions We look forward to having laboratories consolidate their clinical data for better clinical correlation and improvement in their “cut off” and CI. We continue our commitment to maximize the educational aspects of these exercises and to improve the PT program. The use of CD31 and CD34/HLADR staining and their use in the EPC selective analysis, continues to be a viable approach for several laboratories. M.R. Carreno: Consultant; Company/Organization; OLERUP. Inc. B. Vanherberghen: Employee; Company/Organization; Absorber, AB. H. Hall: Employee; Company/Organization; Absorber, AB.