A Generic Growth Test Method for Improving Quality Control of Disposables in Industrial Cell Culture
Independent data, using several different cell lines and growth media, reported growth inhibition resulting from the use disposable bags and suggests a method that can be implemented for quality control at disposable-bag vendors.
Figure 1: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines—results from Company 1. (ALL FIGURES
COURTESY OF AUTHORS)
Figure 1 shows the cell growth and viability for a CHO cell line previously observed at Company 1 to have growth inhibition when media
was stored and warmed in disposable bags from Vendor A, as well as from another CHO line that did not exhibit growth inhibition.
Cells grew to the highest densities when media were prepared from water incubated in glass bottles (Figure 1, Glass incubated water). One lot of bags from Vendor A resulted in limited growth inhibition for each CHO line (Lot 1) while
another lot (Lot 2) affected growth significantly during passages one and two, where viability was also lower than other cases
(Figure 1, Vendor A incubated water, CHO Line 2, Bag Lot 2).
Figure 2: Normalized cell growth and viability of NS0 and Chinese hamster ovary (CHO) cell lines—results from Company 2.
Figure 2 shows the results from Company 2 for an NS0 line and a CHO line. The NS0 cell line experienced a severe impact on growth and
viability when cultured in medium derived from one lot of bag-incubated water (Figure 2, Vendor B incubated water, NS0 Line, Bag Lot 1). This same medium, when stored at 2–8°C for an additional duration (16 weeks
in total) in a glass bottle, still maintained its growth inhibitive properties on this cell line (Figure 2, Vendor B incubated water, NS0 Line, Bag Lot 1, Aged Medium). However, this bag did not exhibit any growth inhibitive effects
on the CHO cell line evaluated (Figure 2, Vendor B incubated water, CHO Line, Bag Lot 1). A second lot of bag-incubated water was able to support cell growth in the
sensitive NS0 cell line (Figure 2, Vendor B incubated water, NS0 Line, Bag Lot 2).
Figure 3: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines—results from Company 3.
Company 3 assessed cell growth and viability on one CHO cell line (Figure 3) using two vendors and two lots of bags from each vendor. Growth was inhibited by nearly 50% when water incubated in Vendor
A bags was used to make medium (Figure 3, Vendor A incubated water). Cell viabilities were not affected, however. For the cell line tested, there were no inhibition
effects on cell growth and viability observed when using medium prepared from water incubated in Vendor B bags for both lots
of bags tested.
Figure 4: Normalized cell growth and viability of Chinese hamster ovary (CHO) cell lines—results from Company 4.
Company 4 assessed cell growth and viability in media incubated in bags from three vendors (Figure 4). Vendor C bags led to the most pronounced growth and viability effects. In the case of media held in Vendor C bags, this
CHO line did not grow at all (Figure 4, Vendor C incubated water). Vendor A bags, shown to inhibit CHO cell growth in a cell line from Company 1 (Figure 1) and Company 3 (Figure 3), led to 60–80% growth inhibition while viability was less affected. Vendor B bags did not lead to any pronounced growth
or viability effects.