Figure 4.

The challenge of GAPDH-B4GALNT2 tagging DF-1 cells with AIV and NDV. (A) Wild-type DF-1 cells and DF-1 clone #12 were infected with H5N8, H9N2, and NDV [Multiplicity of infection (MOI) of 0.1]. Viral titers were determined using TCID₅₀ assays after 12, 24, and 36 h of infection. (B) Survival rates of wild-type DF-1 cells and DF-1 clone #12 were measured using WST-1 reagent after 24, 48, and 72 h of infection of H5N8, H9N2, and NDV. (C) Viral M gene expression of wild-type DF-1 cells and clone #12 was measured after 6 h post-infection through RT-qPCR. Data were analyzed by paired t-test. *p < 0.05, **p < 0.01, ***p < 0.005, ****p < 0.0001.