FIG 3.

Reduced and unsustained virus-specific and neutralizing serum Ab coincides with decreased virus-specific ASC in the absence of CD19. (A) Virus-specific IgM, IgG, and neutralizing Ab in sera of uninfected (day 0 p.i.) and infected mice at the indicated times p.i. (B and C) CLN (B) and bone marrow (C) were analyzed for virus-specific IgG ASC by ELISPOT assay. Representative wells are shown for CLN at day 14 and BM at day 21 p.i. The graphs show frequencies of virus-specific IgG ASC spots and spot diameters. The data represent the means and SEM of individual mice from 3 separate experiments, each comprising 2 to 4 individual mice per time point and group. Statistically significant differences between WT and CD19^−/− mice, determined by unpaired t test, are indicated by asterisks: *, P < 0.05; **, P < 0.01; ***, P < 0.001. Significant differences between time points within the same group are also indicated: #, P < 0.05.