Abstract
Parvovirus B19 (B19), which may contaminate red cell components for blood transfusion, is known to be resistant to several viral inactivation methods. To increase the safety of hemoglobin solutions as a source of red cell substitutes, we investigated the removal of parvovirus B19 from hemoglobin solution using nanofiltration. The hemoglobin solution spiked with parvovirus B19 was tangentially filtered using the BMM-35 filter (mean pore size of 35 nm) followed by BMM-15. The parvovirus B19 of 108.5 PT50 (median PCR titer)/10 μL was not changed after the BMM-35 filtration. However, the BMM-15 filtration decreased the parvovirus B19 from 108.3−8.7 PT50 to 101.3−2.2 PT50, indicating more than 6 log10 reduction. When the initial parvovirus B19 of 106.0 PT50 was subjected to the BMM-15 filtration, the residual virus was 10−0.3−0.5 PT50 or undetected in some fraction of the filtrate. Hemoglobin recovery was 70.4 ± 3.4%. The ratio of methemoglobin was not changed during the filtration. These findings indicate that the BMM-15 filtration is a promising approach to prepare a safer hemoglobin solution for red cell substitutes.