Fig. 2

Humoral immune responses of the DNA vaccines in the immunized mice. 50 μg of DNA vaccines were biweekly intramuscularly injected into the mice for three times. The IgG titers of multiples groups were detected by ELISA at 1, 3, 5, and 7 weeks after the last immunization. All data were expressed as mean ± SD (n = 6). ^**, p < 0.01. ^***, p < 0.001 versus the pcDNA3.1 group. ^#, p < 0.05, ^##, p < 0.01, ^###, p < 0.001 versus the PAL/PiLE/FLaA group