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Scrapie removal using Planova virus removal filters
J Tateishi1, T Kitamoto, S Mohri
1Dept. of Neuropathology, Kyushu University, Japan.
Abstract:
As a possible method for reducing the risk of transmissible spongiform encephalopathy (TSE) infection, Planova virus removal filters were tested for their ability to remove scrapie agent ME7. Albumin solution was spiked with high-titre ME7 and filtered through three different pore sizes of Planova filters. Infectivity of the pre- and post-filtration samples was assayed in log dilutions by intracerebral inoculation into C57B1/6 mice. Filtration of albumin solution in the absence or presence of a detergent (Sarkosyl) with Planova 35N (35+/-2 nm mean pore size) removed the contaminating scrapie agent with reduction factors of 4.93 log10 and 1.61 log10, respectively. Filtration, both in the absence and presence of detergent with Planova 15N (15+/-2 nm mean pore size), and in the presence of detergent with Planova 10N (9+/-2 nm mean pore size), showed high levels of scrapie reduction of >5.87 log10, >4.21 log10, and >3.80 log10, respectively, with no residual infectively detected in any of the filtrate samples. The effectiveness of Planova 35N filtration for the removal of infectivity of this TSE agent is greatly reduced in the presence of a strong detergent, but Planova filters with 15 nm or smaller pore size membranes can remove such infectivity at high reduction rates.
Insights
Planova filters effectively remove transmissible spongiform encephalopathy (TSE) agents like scrapie. Smaller pore sizes (15nm or less) demonstrate high reduction rates, even with detergents, ensuring filtrate safety.
Area of Science:
- Biotechnology
- Neuroscience
- Infectious Diseases
Background:
- Transmissible spongiform encephalopathies (TSEs) pose significant health risks.
- Effective methods for removing TSE agents are crucial for product safety.
- Scrapie agent ME7 is a model for TSE contamination.
Purpose of the Study:
- To evaluate the efficacy of Planova virus removal filters in eliminating scrapie agent ME7.
- To determine the impact of filter pore size and detergents on TSE agent removal.
Main Methods:
- Albumin solutions spiked with scrapie agent ME7 were filtered using Planova filters with pore sizes of 35N, 15N, and 10N.
- Filtration was performed with and without the detergent Sarkosyl.
- Infectivity of pre- and post-filtration samples was assessed via intracerebral inoculation in C57B1/6 mice.
Main Results:
- Planova 35N filters showed reduced efficacy in the presence of detergent (1.61 log10 reduction).
- Planova 15N and 10N filters achieved high scrapie reduction rates (>5.87 log10 and >3.80 log10, respectively), with no detectable infectivity in filtrates.
- Smaller pore size filters (≤15 nm) demonstrated robust removal of TSE agents.
Conclusions:
- Planova filters, particularly those with pore sizes of 15 nm or smaller, are highly effective in removing TSE agents like scrapie.
- Filter performance can be affected by detergents, with smaller pore sizes maintaining efficacy.
- These findings support the use of Planova filters for reducing TSE infection risk.
