Fig. 3.
Plaque-reduction neutralization assay showing the effect of A-virus incubation with anti-A/B–containing human serum.
A and H virus supernatants, diluted to 103 PFU/mL, were incubated with a human O-type reference serum, lacking measles-specific Ab and previously diluted 1:5 in PBS. Similarly, diluted A and H virus supernatants were incubated with the same serum, previously either decomplemented by heat-inactivation, or incubated with A or Galα1-3Galβ1-4GlcNAc trisaccharides. Subsequently, virus/serum mixtures were analyzed for viral titers by a plaque-reduction neutralization assay on Vero cells. Results (mean SEM) in pentuplicates are shown as the mean percentages as compared with the untreated (PBS) A- and H-virus titers (100%). ND denotes experimental conditions involving H virus that were not determined.