IFNB1 and infection: NS1 mutants D2N†, L98S, M106I + L98S, M106V + M124I, and D125G all significantly enhanced viral growth throughout the course of infection in IFN-β primed cells when compared to rHK-wt (p<0.001, p<0.01, p<0.01, p<0.05, p<0.001, respectively; two-tailed paired t-test) (Fig. 6, right panel).