A potentially improved approach to methylene blue virus inactivation of plasma: the Maco Pharma Maco‐Tronic system

Abstract

. Plasma was subjected to methylene blue (MB) photochemical virus inactivation using the Maco Pharma Maco‐Tronic system which allows three units to be illuminated together, thus reducing processing time. The plasma bag system used incorporates an integral membrane plasma filter and a dry MB pill which dissolves in the plasma to give a 1‐µm concentration. There is computer‐controlled processing and datalogging. In an assessment of 10 pools of Group A plasma, the losses of coagulation factors, following MB/light treatment, were 23% fibrinogen, 10% FV, 26% FVIII, 11% FIX and 13% FXI. Group O, Group B and Group AB plasmas were not tested. Von Willebrand factor (vWf) multimers showed no substantial change when treated with MB, and no losses were seen for antithrombin III (ATIII), protein C and vWf:Ag. Measurements of C3a, C5a, prothrombin fragment 1+2 and FXIIa indicated that there was no activation as a result of filtration.