FIG 7.

Protection against lethal challenge. (A) Groups of vaccinated mice and a mock-vaccinated control were challenged intranasally with a lethal dose of influenza virus A/PR/8/34 (5× LD₅₀). Mice were immunized with HA-CAP, HA2-CAP, HA2-CAP–M2-CAP, LAH-CAP, and M2-CAP VLPs and with GFP-CAP VLPs and PBS (mock) alone. Survival was monitored for 14 days and is expressed as the percentage of surviving mice. (B) The body weights of the infected mouse groups (n = 6) were monitored for 14 days. Values represent the weights of individual mice expressed as a percentage of the initial weight on the day of inoculation (100%).