IFITM3 and viral infectious disease: Zhu et al. (2015) evaluated how interferon-inducible transmembrane protein 3 (IFITM3), which is transferred by flotillin-2+ CD63+ exosomes from DENV-2 NGC-infected HUVECs and 293T cells, is expressed in exosome-stimulated HeLa cells, increasing cell resistance to viral infection and significantly reducing DENV-2 entry [92].