A Multiagent Alphavirus DNA Vaccine Delivered by Intramuscular Electroporation Elicits Robust and Durable Virus-Specific Immune Responses in Mice and Rabbits and Completely Protects Mice against Lethal Venezuelan, Western, and Eastern Equine Encephalitis Virus Aerosol Challenges

Figure 5

Virus-neutralizing antibody responses of vaccinated rabbits. New Zealand White rabbits ( per group) were vaccinated on days 0, 28, and 230 with 0.5 mg of the VEEV, WEEV, or EEEV DNA vaccine or with 0.5 mg each of the VEEV, WEEV, and EEEV DNA vaccines (3-EEV DNA vaccine) delivered by IM EP. Serum samples obtained on days 27, 42, 230, 266, and 349 were assayed for neutralizing antibodies against VEEV IAB (a), WEEV (c), or EEEV (d) by PRNT. The day 42 serum samples from rabbits vaccinated with the VEEV DNA or 3-EEV DNA were also assayed for neutralizing activity against heterologous VEEV subtypes IC, ID, and IE and MUCV (b) by PRNT. The group mean log₁₀ PRNT₈₀ titers along with the SEM are shown. for comparison of titers between groups.

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