FIG. 3.
Analysis of 35S-labelled polypeptides present in immune precipitates formed by the reaction of MAbs specific for the P (a), HN (b), and F (c) proteins of SeV with soluble antigen extracts made from BF cells infected with SeV for 1 day (lanes 1 and 2) or 3 days (lanes 3 and 4). The cells were pretreated with IFN 24 h (100 IU/ml) prior to infection (lane 1) or left untreated (lanes 2 to 4). At 24 h p.i., exogenous IFN (100 IU/ml) was added to the culture medium of cells used to make the extract shown in lane 4.