For this purpose, PBE cells were challenged with SIV H1N1 (Figure 5) or H3N2 (Figure 6) and the expression of IFN-β and the antiviral factors Mx1, Mx2, IFITM1, OAS1, OAS2, and OASL were evaluated at different hours post-infection. This evidence concerns the gene IFNB1 and infection.