Early anti-IL-10 therapy improves virus control 30 days p.i. a) Spleen cells from naïve, LCMVARM, and LCMVClone13-infected mice with and without anti-IL-10 treatment (day 30 p.i.) were stained with LCMV tetramers DbGP33 and DbNP396. The numbers shown are the frequency of tetramer+ cells per CD8+ T cells. Plots are representative of 5 mice. b) IFNγ production by CD8 T cells 30 days p.i. Splenocytes were stimulated with LCMV MHC class I restricted peptides, GP33-41 or NP396-404 or class II peptides GP61-80 and NP309-324 and then assayed for IFNγ production by ICCS. All plots are gated on CD8 T cells and the numbers indicate the frequency of CD69+ IFNγ+ cells. c) Anti-IL-10 treated mice exhibited lower viremia at 30 days p.i Sera from LCMVClone13-infected mice without (open circles) and with (filled circles) anti-IL-10 treatment were tittered for infectious virus by plaque assay. Naïve and LCMVARM immune mice were free of virus (not shown). d) Anti-IL-10 treatment in mice with established persistent infections does not lead to lowering of viral titers. Cohorts of mice infected 30 days earlier with LCMVClone13 were injected with anti IL-10 therapy on days 30–34 p.i Their sera were collected two weeks later and assayed for infectious virus by plaque assay. The LCMV titers from untreated (open cirlces) and anti-IL-10 treated (filled circles) mice are shown.