2.2 Cell line and media formulation
A GSK proprietary HEK293T suspension-adapted stable cell line was used for this study. This cell line has the green fluorescence protein (GFP) transgene as well as the LVV packaging constructs stably integrated in the host genome (Chen et al., 2020). When induced, this cell line produces LVV with an RNA genome encoding for GFP. For cell culture, the proprietary media formulation from GSK’s 2 L bioreactor (Sartorius AG, Gottingen, Germany) process model was utilised. For the STR cultures, the media was also supplemented with 0.5 mL/L antifoam (Cytiva, Washington, United States) to allow direct sparging and prevent excessive foaming.