Tangential flow filtration is frequently used in the biotechnology industry for the purification of proteins. Here we focus on the use of tangential flow filtration for virus capture. Large scale production of virus vectors for gene therapy applications and viral vaccines is a major challenge. It is estimated that between 1011 and 1014 viral vectors will be required to satisfy gene therapy regimens.

Tangential flow filtration of human influenza A virus and Aedes aegypti densonucleosisvirus (AeDNV) has been investigated. Large scale production of human influenza A virus is important in the manufacture of influenza vaccines. These enveloped virus particles have an average size of about 100 nm. AeDNV is a non enveloped virus. The particle are about 26 nm in size. These virus particles infect the Aedes aegypti mosquito. The Aedes aegypti mosquito is a carrier of viruses that are human pathogens which cause dengue and yellow fever. Consequently development of an AeDNV vector may find important applications in integrated vector borne disease control programs against human pathogens such as dengue and yellow fever.

The results obtained here indicate 100 and 300 kD cut off ultrafiltration membranes may be used to concentrate the human influenza A virus particles in the retentate. However 300 kD membranes allow for better removal of host cell DNA and proteins in the permeate. Use of 0.1 µm microfiltration membranes leads to fractionation of the virus particles. Viral fragments pass into the permeate while aggregated virus particles and virus particles bound to host cell membranes are concentrated in the retentate. In the case of the smaller AeDNV particles 100 kDa membranes are required in order to ensure concentration of the virus particle in the permeate.