Fig. 5.

T cells proliferation assay. T cells proliferation was examined by Cell Proliferation ELISA BrdU Kit, and results were expressed as a stimulation index (SI) of chickens vaccinated with PBS, L. lactis, L. lactis HA1, L. lactis HA1-Fc and inactivated H9N2 vaccine. The data were showed as means ± SD (n = 5). **P < 0.01 relative to PBS and L. lactis. ^##P < 0.01 relative to L. lactis HA1. ^$$P < 0.01 relative to L. lactis HA1-Fc