Dual preparation of plasma and platelet concentrates in platelet additive solution from platelet concentrates in plasma using a novel filtration system

Background and Objectives Platelet concentrates suspended in a platelet additive solution (PAS-PC) are associated with a reduction in allergic response and are suitable for preparing pathogen-inactivated PC. We aimed to develop an efficient platform for the dual preparation of PAS-PC and platelet-poor plasma. Materials and Methods PAS-PC was prepared in six steps by using a hollow-fibre system based on cross-flow filtration: priming, loading PC, loading PAS, collection of filtered liquid (flow-through) and collection of platelets by washing with PAS followed by washing with air. In this study, the efficacy of platelet and plasma protein recovery and characteristics of recovered PAS-PC and flow-through plasma were analysed in detail. Results Recoveries of platelet in PAS-PC and plasma protein in the flow-through were 95.4% +/- 3.7% and 61.6% +/- 5.0%, respectively. The residual plasma protein in PAS-PC was 34.1% +/- 2.8%. Although the expression level of CD62P, a platelet activation marker, in recovered platelets was approximately 1.2-fold of that in original platelets, swirling patterns were well retained, and aggregation in PAS-PC was not visible. Agonist-induced aggregabilities, platelet morphology and hypotonic shock recovery were conserved. The patterns of plasma protein and lipoprotein in the flow-through were comparable with those in the original PCs. The multimeric pattern analysis of VWF remained unaltered. Conclusion We propose a highly efficient preparation system that enables the simultaneous production of PAS-PC and platelet-poor plasma. It also achieves a high recovery of functionally well-retained platelets with very low activation.