Figure 4. Blocking IL-10R signalling increases cellular influx into the lungs and delays recovery during RSV infection.

BALB/c mice were infected with 10⁶ PFU RSV i.n. (day 0). Where indicated, mice were injected with anti-IL-10R antibody on day -1 (i.p.), 3 (i.p. and i.n) and 6 (i.p.) post RSV infection. Control groups were injected with rat IgG. (A) Illness was monitored daily by changes in weight for 8 days after RSV infection; the percentage of original weight is shown. (B) Viral titer was measured in the lung on day 4 post infection by quantifying RSV L gene copies by qPCR. (C) Total numbers of cells in the lung and BAL were enumerated on day 4 and 8 from naïve or RSV infected mice. (D) Total numbers of neutrophils in the BAL were quantified using differential cell counting of H&E stained cytospins slides on day 4 and 8 post infection. (E) Total numbers of NK cells (CD3⁻ NKp46⁺) and CD3-gated, CD4⁺Foxp3⁻ and CD8⁺ T cells in the lung were quantified using flow cytometry on day 4 and 8 post RSV infection. Error bars indicate the SEM. The data are representative of two independent experiments with n = 4–5 mice per group.