IFNAR1 and infection: Although the production of both cytokines in IFNAR-blocked BMMCs was lower than that of IFNAR−/− cells, it was still significantly higher than IFNAR-intact cells at 20 h post-infection (9.30% ± 0.79% for IL-6 and 14.75% ± 1.20% for TNF-α) (Figure 5).