IFITM3 monoclonal antibody

Interferon-induced transmembrane protein (IFITM) family members are composed of short amino- and carboxy-termini, two transmembrane domains, and a cytoplasmic domain. There are four family members in humans: IFITM1, IFITM2, IFITM3, and IFITM5. Mice have two additional family members, IFITM6 and IFITM7. Basal expression of IFITM proteins is observed in some cells and expression can also be induced by type I and type II interferons. The primary function of IFITM family proteins appears to be viral restriction, as IFITM proteins inhibit cytosolic entry of viruses by preventing fusion of viral and host membranes. The mechanism by which IFITM proteins inhibit fusion is unclear. Although IFITM proteins are present on both the plasma membrane and intracellular membranes, they most effectively restrict viral fusion in late endosomes and lysosomes. In addition, different family members exhibit specific viral preferences. For example, IFITM3 is most effective at restricting influenza A infection, while IFITM1 is more successful in controlling filoviruses and SARS.