Figure 2.

Optimization of VSV-ΔG-S_CTΔ21 and VSV-ΔG-S_{Omicron-CTΔ21}-GFP production in 125-mL and 1-L bioreactors

(A) Growth curves with VSV-ΔG-S_CTΔ21 in plate- and bioreactor-based virus production runs. We infected 145-cm² tissue culture plates and 125-mL and 1-L Celstir bioreactors at an MOI of 0.05 PFU/cell. Cultures were harvested at the indicated times and titered on Vero cells. (B) Bright-field images of Vero cells in a 145-cm² plate or crystal violet–stained Vero cells grown on Cytodex 1 microcarriers in 125-mL Celstir bioreactors. Cultures were infected with an MOI of 0.05 PFU/cell with VSV-ΔG-S_CTΔ21. Scale bar, 360 μm. (C) Growth curves with VSV-ΔG-S_{Omicron-CTΔ21}-GFP in plate- and bioreactor-based virus production runs. We infected 145-cm² tissue culture plates and 125-mL and 1-L bioreactors with an MOI of 0.002 PFU/cell and harvested at the indicated times and titered on Vero cells. (D) Bright-field images of Vero cells in a 145-cm² plate or crystal violet–stained Vero cells grown on Cytodex 1 microcarriers in 125-mL bioreactors. Cultures were infected with an MOI of 0.002 PFU/cell with VSV-ΔG-S_{Omicron-CTΔ21}-GFP. Scale bar, 360 μm. (E) Schematic of optimized 72-h VSV-ΔG-S_CTΔ21 virus production protocol in 125-mL and 1-L Celstir bioreactors. Mean ± SD is shown. Two-way ANOVA using Sidak’s HSD was used in (A) and (B). For (A), n = 2 for plates, n = 4 for 125-mL and 1-L bioreactors. p values from pairwise comparisons between plates and 125-mL bioreactors are shown below the line graph; comparisons between 125-mL and 1-L bioreactors are shown above the line graph. For (B), n = 2 for plates, n = 2 for 125-mL bioreactor, and n = 1 for 1-L bioreactor. p values are generated only from comparisons between plates and 125-mL bioreactors.