Fig. 2From: Roles of the highly conserved amino acids in the second receptor binding site of the Newcastle disease virus HN proteinQualitative detection results of cell surface expression efficiency of mutant HN proteins. Monolayers of BHK-21 cells transfected with wt or mutant HN genes were incubated with a mixture of two monoclonal antibodies specific for the NDV HN protein and FITC-labelled goat anti-rabbit IgG. (Magnification: 200 × ). a The IIFA results of site-directed mutants. b The IIFA results of fragment deletion or replacement mutantsBack to article page