Item

Abstract

Human influenza vaccines are traditionally produced in embryonated chicken eggs. However, due to several disadvantages of this method, mammalian cell culture based influenza vaccine production processes are currently being established demanding new virus purification methods. Our study provides comprehensive results from three different strategies to capture Madin-Darby canine kidney (MDCK) cell culture-derived influenza virus particles (A/Wisconsin/67/2005, A/Puerto Rico/8/34, B/Malaysia/2506/2004) based on affinity and pseudo-affinity adsorption. First, an affinity based capture step, lectin-affinity chromatography (LAC), was developed. This method was investigated concerning the selection of lectins and matrices, viral recoveries and contaminant depletion as well as process robustness. LAC showed a high degree of contaminant reduction, in particular host cell dsDNA depletion. The results from LAC represent a high potential of an affinity capture step at the beginning of a downstream process for production of viral vaccines. Influenza viruses have an affinity to sulfated carbohydrates, such as heparin or sulfated cellulose. Hence, column based Cellufine® sulfate is often used in industrial influenza virus purification. The main disadvantage of this method is the limited flow rate, due to high back pressure, leading to suboptimal process productivity. To overcome this drawback, we have developed a second capturing method for influenza viruses based on sulfated reinforced cellulose membranes (SCM). Compared to commercially available cation exchange membrane adsorbers and column based Cellufine® sulfate resin, these membrane adsorbers achieved high product recoveries and contaminant reduction. In addition, the SCM allow an increased flow rate during capturing leading to superior productivity compared to conventional bead chromatography. Hence, this method is an economic alternative for industrial influenza vaccine production. The third purification strategy was capturing of influenza viruses by immobilized metal affinity chromatography (IMAC) using zinc modified membrane adsorbers. This method shows valuable purification results for the influenza virus strain A/Puerto Rico/8/34. However, IMAC depends highly on the primary structure of viral envelope proteins as well as the accessibility of certain amino acids. Hence, IMAC is an interesting capturing method of A/Puerto Rico/8/34 in a laboratory scale, but is only of limited interest for industrial vaccine production processes.