Lymphocyte Proliferation Assay

A T-cell proliferation assay was performed on the splenocytes using a 3-(4,5-dimethylthiazol-2-yl)-2-5-diphenyltetrazolium bromide (MTT) assay. The cells were adjusted to a concentration of 2 × 10⁶ cells/mL and added to a 96-well plate at 100 μL per well. The cells were stimulated with concanavalin A (positive stimulus), inactivated FMDV 146S of serotype A, or RPMI 1640 medium (negative stimulus). The final concentration of each stimulus was 10 μg/mL. The stimulation index (SI) was the ratio of the optical density at a wavelength of 490 nm (OD₄₉₀) of the stimulated group to that of the unstimulated group.