BST2 and infection: In particular, Myxovirus resistance protein 2 (MX2) inhibits early stages of infection [18], while other ISGs such as Apolipoprotein B mRNA editing enzyme, catalytic polypeptide-like 3G (APOBEC3G), Tripartite motif-containing 22 (TRIM22) and Tetherin target later stages of infection, such as virus release or the infectivity of virus particles [19–21].