Treatment with anti-CCL11 does not compromise protection. Levels of RSV-specific IgG1 (a), IgG2a (b), and Ig (c) were measured by ELISA. The data presented are mean absorbance values ± SEM of four mice per group at a serum dilution of 1:200 (a and b) or 1:800 (c). Similar results were obtained at other serum dilutions. (d) Recovery of infectious virus from whole lung homogenates of individual mice, primed and treated as indicated, was measured by titration on HEp-2 monolayers 4 days after challenge with RSV. Each data point represents a single mouse.