IFITM1 and infection: To reveal whether IFITM1 could respond to the infection of HBV, we compared the mRNA amount of IFITM1 in blood samples between healthy persons and hepatitis B surface antigen (HBsAg), hepatitis B extracellular antigen antibody (HBeAb), hepatitis B surface antibody (HBcAb) test positive patients according to 2017 European Association for the Study of the Liver Guidelines (20); the results showed significantly increased expression of IFITM1 in HBsAg, HBeAb, and HBcAb test positive patients (Fig. 1A).