In‐vitro evaluation of the PALL Leukotrap Affinity Prion Reduction Filter as a secondary device following primary leucoreduction

Background and Objectives  A filter (PRF1) designed to remove abnormal prion proteins from red-cell units has been developed. The purpose of this study was to evaluate the quality of red cells produced using this device. Materials and Methods  Leucocyte-depleted red-cell units (CPD, CPD-A1 and CPD/SAGM) processed according to standard UK practices were filtered using PRF1. Filtered and control units were stored and sampled on day 1, day 7 and on the date of expiry and were tested using standard measures of red-cell quality. Results  Filtered units were found to have significantly higher percentage haemolysis levels, lower haemoglobin levels and a smaller volume compared with controls. All results, however, were well within the permitted 0·8% haemolysis level at the end of storage and all units met the UK guidelines for haemoglobin and volume. The other test parameters measured showed no significant differences between the test and control units. Conclusions  The PRF1 filter was found to be easy to use and resulted in red-cell units that met all relevant UK and European Guidelines.