PSORALEN-MEDIATED PHOTODECONTAMINATION OF PLATELET CONCENTRATES - INACTIVATION OF CELL-FREE AND CELL-ASSOCIATED FORMS OF HUMAN-IMMUNODEFICIENCY-VIRUS AND ASSESSMENT OF PLATELET-FUNCTION IN-VIVO

BACKGROUND: Treatment of platelet concentrates (PCs) with psoralens an d broad-band ultraviolet A (UVA) radiation is being examined for the e limination of pathogens that might be present in donated blood. Previo us studies have demonstrated the inactivation of cell-free viruses and the maintenance of platelet integrity with common in vitro assays. ST UDY DESIGN AND METHODS: Human immunodeficiency virus (HIV) in three fo rms-cell-free, actively replicating, and latently infected cell lines- was added to PCs and treated with 50 mu g per mL of 4'-aminomethyl-4,5 ',8-trimethylpsoralen (AMT), 0.35 mM rutin, and broad-and narrow-band UVA light (320-400 nm and 360-370 nm [UVA1], respectively). The inacti vation of added HIV was assessed in tissue culture; platelet hemostati c activity was assessed in thrombocytopenic rabbits. RESULTS: Each for m of HIV was inactivated completely (greater than or equal to 10(5) in fectious units) on treatment with 30 J per cm(2) of UVA1 light. Simila r results were obtained on treatment of 2.5 mL of PCs in test tubes or intact PC units (50 mL) in blood bags. Latently infected cell lines w ere substantially more sensitive than cell-free HIV or HIV that was ac tively replicating. Human platelets treated with 40 J per cm(2) of UVA 1 light had a fully corrected bleeding time shortly after treatment or after 5 days' storage, as assessed in thrombocytopenic rabbits. Plate let hemostatic function began to decrease with 81 J per cm(2) of UVA1 light and was abolished with 113 J per cm(2). At similar fluences, bro ad-band UVA light was more injurious to platelets than was UVA1 light. CONCLUSION: HIV transmission might be eliminated by PCs after treatme nt with AMT and UVA1 light and without a reduction in platelet hemosta tic function.