FIG 1.

1V270/1Z105-induced reduction in lung viral titers correlated with decreased morbidity from influenza virus challenge. WT (BALB/c) mice (4 to 5 animals/group) were immunized with rPR/8 HA adjuvanted with 1V270/1Z105, 1V270, 1Z105, AddaVax, or no adjuvant and subsequently challenged with PR/8 virus 3 weeks after immunization. (A) Virus-challenged mice were monitored for morbidity as measured by weight loss until day 6 postinfection (DPI), when they were sacrificed. Statistical significance of weight loss was assessed by multiple t tests compared to the no-adjuvant group. (B) Lung viral titers from mice sacrificed on day 6 postinfection were quantified by plaque assays. The limit of detection for the plaque assay was 10 PFU/ml. Statistical significance was assessed by an ANOVA for comparison to the no-adjuvant group, and also with the Kruskal-Wallis test. (C) The percentage of body weight lost on day 6 postinfection was plotted against the lung viral titer for each mouse, and a linear regression curve was generated. The Pearson correlation coefficients (r) are shown. *, P < 0.05; **, P < 0.01.