Virus inactivation of plasma by methylene blue/light treatment using a DEHP-free bag system

Background

DEHP is a widely used plasticizer in blood bags. Due to its endocrine disrupting properties European regulators decided to ban its use in medical devices. Although, the final sunset date is not yet clear, DEHP-free blood bags will be essential in Europe within the next years. Inactivation capacity of model viruses varying in structure and biophysical characteristics by Methylene blue (MB)/light treatment of plasma using THERAFLEX MB-plasma system (DEHP-free, Macopharma) was investigated.

Methods

Leuko-depleted plasma was prepared from whole blood using standard blood banking technology (containing DEHP). Plasma units were spiked with virus suspension (10% v/v; Suid Herpes Virus (SHV-1), Bovine Viral Diarrhea Virus (BVDV), Feline Calici Virus (FCV), Vesicular Stomatitis Virus (VSV)). MB/light treatment was done according to manufacturer"s instructions (Macotronic B2 illumination device) with the DEHP-free THERAFLEX MB-Plasma system PROSDV1. Samples were taken after spiking and after illumination with different light doses (30, 60, 90 J/cm²: n=3 and 120 (standard) J/cm²: n=6) The virus titer were determined as tissue culture infective dose (TCID₅₀) by endpoint titration Large volume plating was done to improve the detection limit.

Results

Log₁₀ reduction factors of ≥ 5.89 and ≥ 5.50 log steps were achieved for BVDV at a light dose of 120 J/cm² in the respective experiments with and without intermediate sampling. Log₁₀ reduction factors of ≥ 4.29 and ≥ 4.17 log steps were achieved for FCV, ≥ 4.96 and ≥ 4.92 log steps for SHV-1 and ≥ 5.35 and 4.77 log steps for VSV with and without intermediate sampling.

Conclusion

All of the viruses tested in this study were inactivated with reduction factors ≥ 4 log steps at the final illumination dose of 120 J/cm² using the DEHP-free bag disposable PROSDV1 and the illumination device Macotronic B2. Reduction factors are comparable to data achieved in the past for the DEHP-containing THERAFLEX MB-Plasma system.

Offenlegung Interessenkonflikt:

Study was sponsored by Macopharma Productions (CS).