Restriction of the typically nonrestricted MLV-LP and drastically aberrant morphology with a “foamy” appearance (Fig. S1C) suggest that recombinantly overexpressed IFITMs in HUVEC, which naturally already express IFITM2 and IFITM3 at high levels, may lead to visibly distorted cellular membranes and vesicles and nonspecific effects on infection. This evidence concerns the gene IFITM2 and infection.