Exploring vaccinia virus as a tool for large-scale recombinant protein expression

摘要

A recombinant vaccinia virus was engineered to express enhanced green fluorescent protein (EGPP) under control of the T7 promoter using the VOTE expression system in HeLa cells. Infection of HeLa cells with this virus and induction with IPTG demonstrated the utility of this construct for easily measuring protein expression. This construct was used to evaluate several production parameters, specifically, multiplicity of infection (MOI), volume during infections and serum concentration during the infection phase. In static culture, increasing multiplicity of infection was found to increase expression of EGFP up to a plateau around MOI of 1.0. Expression eras also shown to increase with decreasing volume during the infection phase. Serum concentration during the infection phase was only marginally significant from 0 to 7.5%. Cytodex microcarriers were found to have the best characteristics for HeLa cell growth. These cells were grown and infected microcarier spinner flask culture, and tie maximum expression was 2.2 mug EGEP/(million cells at the dine of infection), demonstrating the ability of this system to successfully express recombinant proteins at larger scale.