MX1 and infection: Of interest, 3pRNA prophylaxis provided long-term protection (i.e., 5 days after treatment) against subsequent IAV infection in vitro (using MLF) or in vivo (i.n. infection) only in B6.A2G-Mx1 mice, although when examining mRNA levels in MFL or mouse lung 5 days after treatment we did not detect evidence of upregulated Mx1 expression.