クロイツフェルトヤコブ病 (CJD) の原因物質の膜除去方法

抄録

We intended to show the possibility of the removal of the Creutzfeldt-Jakob disease (CJD) causative agent by the filtration using the virus removal membrane BMM®, that is, cuprammonium regenerated cellulose hollow fiber. The BMMs with various mean pore size 2r_f ranging between 35 and 75 nm were employed. The supernatant of the centrifuged homogenate obtained from the mouse brains infected with CJD was filtered through BMMs and each filtrate was injected intracerebrally into mice. The concentration of the CJD infectious agent was evaluated through the mean death day caused by CJD after the injection. The dependence of this concentration of the filtrate on 2r_f the change in this concentration of the double filtration, and the change in the concentration of the filtrate from the solution after the treatment of the surfactant “Sarkosyl” was investigated. The infection of CJD was judged from the pathology of spongiform encephalopathy and from the generation of the CJD isoform of Prion Protein (PrPCJD).
The results were summerized as follows : (1) The infectivity of the filtrate decreased when 2r_f decreases, and after the filtration using the BMM with 2r_f value of 35 nm, this infectivity desappeared completely indicating the logarithmic rejection coefficient was more than 6. (2) The double step filtration using two BMMs with 2r_f of 60nm gave about 10% increase in the rejection coefficient comparing with the case of the single step filtration. (3) The treatment of the Sarkosyl made the permeability of the CJD causative agent through the BMM with 2r_f of 40nm increased to 100% and the infectivity increased to about five hundreds times of that of the original solution.