Disposable Bioreactors - Disposable Bioprocessing Systems - page 107

38. J Virol Methods . 2007 Nov;
145(2):155-61. Epub 2007 Jul 2.
Production of recombinant
adeno-associated vectors using
two bioreactor configurations at
different scales. Negrete A, Kotin
RM. Laboratory of Biochemical
Genetics, National Heart, Lung,
and Blood Institute, US National
Institutes of Health, Bethesda,
MD 20892.

The conventional methods for producing recombinant
adeno-associated virus (rAAV) rely on transient
transfection of adherent mammalian cells. To gain
acceptance and achieve current good manufacturing
process (cGMP) compliance, a clinical-grade rAAV
production process should have the following
qualities: simplicity, consistency, cost-effectiveness,
and scalability. Currently, the only viable method for
producing rAAV in large scale, for example, > or
=10(16) particles per production run, utilizes
baculovirus expression vectors (BEVs) and insect
cells suspension cultures. The previously described
rAAV production in 40 L culture using a stirred-tank
bioreactor requires special conditions for
implementation and operation that are not available
in all laboratories. Alternatives to producing rAAV in
stirred-tank bioreactors are single-use, disposable
bioreactors, for example, Wave. The disposable bags
are purchased presterilized, thereby eliminating the
need for end-user sterilization and also avoiding
cleaning steps between production runs, thus
facilitating the production process. In this study,
rAAV production in stirred tank and Wave
Bioreactors was compared. The working volumes
were 10 and 40 L for the stirred-tank bioreactors and
5 and 20 L for the Wave Bioreactors. Comparable
yields of rAAV, approximately 2E+13 particles per
liter of cell culture, were obtained in all volumes and
configurations. These results demonstrate that
producing rAAV in large scale using BEVs is
reproducible, scalable, and independent of the
bioreactor configuration.

39. Bioprocess Biosyst Eng . 2007 Jul;
30(4):231-41. Evaluation of a
novel Wave Bioreactor cellbag
for aerobic yeast cultivation.
Mikola M, Seto J, Amanullah A.
Fermentation and Cell Culture,
Merck and Co., P.O. Box 4,
Mailstop WP26C-1, West Point,
PA 19486. mark_mikola@merck.
com

The Wave Bioreactor is widely used in cell culture due
to the benefits of disposable technology and ease of
use. A novel cellbag was developed featuring a frit
sparger to increase the system's oxygen transfer. The
purpose of this work was to evaluate the sparged
cellbag for yeast cultivation. Oxygen mass transfer
studies were conducted in simulated culture medium,
and the sparged system's maximum oxygen mass
transfer coefficient (K L a) was 38 h(-1). These
measurements revealed that the sparger was
ineffective in increasing the oxygen transfer capacity.
Cultures of Saccharomyces cerevisiae were successfully
grown in oxygen-blended sparged and oxygen-
blended standard cellbags. Under steady-state
conditions for both cellbag designs, K L a values as high
as 60 h(-1) were obtained with no difference in growth
characteristics. This is the first report of a successful
cultivation of a microbe in a Wave Bioreactor,
compared to conventional seed expansion in shake
flasks and stirred-tank bioreactors.