Adeno-associated and lentiviral vector production in 2D and 3D formats
with adherent cells in chemically defined, blood-free media
Abstract
Large scale manufacturing of viral vectors or vaccines with adherent
cells still relies heavily on the inclusion of fetal bovine serum for
the growth and production phases. The inclusion of serum presents
numerous problems with the undefined chemical makeup, the undesirable
safety profile, and the constraints and limitations on the global
supply. Despite these challenges, alternatives to serum for adherent
cells have been limited; however, advances in large-scale production of
recombinant human proteins have enabled the advancement of blood-free
media that can support adherent cell growth. In order to circumvent the
need for serum in adherent platforms, we developed a serum and
blood-free, chemically defined medium specific for adherent human
epithelial kidney cells and evaluated growth kinetics as well as viral
vector production with associated adenovirus and lentivirus. We observed
doubling times equal to or faster than doubling times observed in serum
containing medium. We also demonstrate transfection efficiencies and
viral titers that are equivalent to or higher than that of serum. Our
results demonstrate that fetal bovine serum is not required for culture
of adherent HEK cells, and that a serum-free, blood-free, chemically
defined approach can be reliably implemented in the production of viral
vectors for gene therapy.