Affinity recovery of Moloney Murine Leukaemia Virus

Lipid enveloped retroviruses such as Moloney Murine Leukaemia Virus (MoMuLV) are commonly used gene therapy vectors. Downstream processing protocols used for their purification are time consuming and a potentially generic, single step capture method for the recovery of retroviral particles is proposed that exploits streptavidin-biotin affinity chromatography. The ability of four conventional adsorbent solid phases, Fractogel®, Sepharose, Magnespheres® and STREAMLINE immobilised with streptavidin, to capture and recover biotinylated Moloney Murine Leukaemia Virus was studied. MoMuLV can be biotinylated whilst retaining infectivity and the biotinylated virus can be adsorbed to Streptavidin Magnespheres yielding a 2298-fold increase in titre. For optimal virus biotinylation purification using Fractogel® streptavidin can yield a 1896-fold increase in cfu/mg of protein and a 1191-fold decrease in DNA/cfu. Infectious virus can be recovered from Fractogel® streptavidin with a maximum recovery of 16.7%.