FIG. 4.

Polyclonal antibody to CD46 does not inhibit infections by the Montefiore 89 wild-type strain of measles virus. Antibodies to CD46 and the marmoset SCR1 were combined and tested for their ability to inhibit infections by Montefiore 89 and Edmonston measles virus in B95-8 and Vero cells. Cells were treated with CD46 and SCR1 immune antibodies (A, C, and E) or preimmune serum (B, D, and F). CD46 antibodies at dilutions of 1:10 had no effect upon infections of B95-8 cells by the wild-type Montefiore 89 virus (A) but partially inhibited infections of the same type of cells by the Edmonston strain of virus (C). The same antibodies at dilutions as low as 1:400 completely inhibited the infection of Vero cells by the Edmonston virus (E). Infections were assessed by the formation of syncytia or multinucleated cells. Bar, 3 μm.