OSBP and viral infectious disease: As for the mechanism associated with the inhibition of membrane fusion, IFITMs have been reported to curtail viral infection, in part by resulting in the accumulation of cholesterol in late endosomes as a result of IFITM-mediated disruption of the interaction between the vesicle membrane-protein-associated protein A (VAPA) and oxysterol binding protein (OSBP) (23).