IFNA1 and hepatitis B virus infection: In addition, we observed that ZAP-S protein expression was further induced in primary human hepatocytes by IFN-α treatment (Fig. 9D), and the levels of ZAP mRNA were elevated in the livers of hepatitis B patients during the immune active phase (Fig. S4), implying that ZAP may also play a role in host immune responses against HBV infection in vivo.