FIG. 2.

Expression of MxA protein in stably transfected human HEp-2-MxA and U937-MxA cells leads to inhibition of SFV multiplication. (A) Western blot analysis of cytoplasmic extracts from various HEp-2-MxA and U937-MxA clonal lines. Samples (50 μg of protein per lane) were separated in SDS–10% polyacrylamide gels and subsequently blotted onto nitrocellulose membranes. The blots were immunostained with a monoclonal mouse anti-MxA antibody. The bands were visualized with enhanced chemiluminescence reagents (Amersham). Quantitation of the optical density was carried out with the video documentation system E.A.S.Y (Herolab, Wiesloch, Germany). The relative MxA levels are shown as arbitrary expression units. (B) Reduction of SFV yields by MxA. The different clonal lines were infected with SFV at an MOI of 0.1. Viral yields in culture supernatants 24 h postinfection were determined by the TCID₅₀ method.