Figure 6.

Plasma IgG1 and IgG2a titers in infected aged mice. Fifteen‐month‐old mice were infected with a mouse‐adapted strain of influenza A/Puerto Rico/8/34 (H1N1; PR8) and treated with Placebo (I + Placebo) or GSH‐C4 (I + GSH‐C4) as described in the Materials and Methods section. At day 8 pi, IgG1 (A) and IgG2a (B) were determined by ELISA as described in the Materials and Methods section. Antibody titers are reported as optical density (OD) of the 1/32000 dilution. Values represent the mean ± SD of five mice, each run in duplicate (n = 10). Unpaired data were analyzed with the Student's t test with Welch correction: *P = 0.01, **P < 0.005, ***P < 0.0005