Nucleic acid-targeted pathogen reduction technique in red blood cells by UV-generated oxygen radicals for optimising recipient safety.

Abstract

A novel pathogen reduction technique based on vacuum ultraviolet (VUV) irradiation was developed to reduce pathogen numbers in red blood cell (RBC) components. Contaminated blood components pose a great risk of infection in blood recipients. The continuous development of blood screening techniques and pathogen inactivating systems has significantly reduced this risk, but many limitations remain. Escherichia coli and Bacillus cereus, and bacteriophage (BP) and Lentivirus (LV) were spiked into suspended red blood cells (sRBCs) or plasma. VUV light with maximum emission at 185 nm and an average dosage of 164 μW/cm2 was placed 5 cm above the targeted products to reduce the pathogen numbers. Treatment for 5 minutes was effective; 3 and 10 log reductions of E coli counts were observed in sRBCs and plasma, and 2 and 3 log reductions of B cereus counts were observed in sRBCs and plasma, respectively. The BP titre was reduced by two and five log points in sRBCs and plasma, respectively; the LV titre was reduced by at least three log points in both sRBCs and plasma. VUV-based irradiation of RBCs does not cause significant structural and functional harmful effects. This novel strategy provides moderate photonic energy to generate oxygen radicals from H2 O and O2 and to selectively decrease DNA integrity of the potential pathogens. The VUV-based pathogen reduction technique is a simple and fast procedure with high pathogen reduction efficacy, low toxicity and limited adverse effects on cellular blood products.