Factors affecting the large scale production of human lymphoblastoid interferon.

Large scale production of human lymphoblastoid (Namalva) interferon (IFN) is carried out in pilot-plant-scale fermentors having up to 250 liter culture volume. Cells are grown in a semi-continuous culture. For IFN production, which is an IFN-alpha (Ly), harvested cells were induced by Sendai virus. Variations in IFN yields of up to ten-fold were observed during long-term cell cultivation. Several factors such as cell concentration, virus concentration, "age" of induced cells and serum substitutions, were investigated for their effect on the fluctuation in the IFN yields. Optimization of the above factors were found to be of great importance in controlling the IFN production and maintaining a stable and high IFN yield.