SrtA/SCPA co-immunization induced more efficient protection against GAS infection.

<p>(A) Mice were i.n immunized three times at 1-week intervals with indicated antigens (SrtA, 10 μg and SCPA, 20 μg) and CTB or infected with GAS (Materials and Methods). 10 days after the last immunization or infection, mice were challenged with a sublethal dose of GAS M1 (Spec^r). NALTs were taken and homogenized for CFU counting 24 hr after challenge. Data are geometric means of two independent experiments. (B) Mice were co-immunized with SrtA/SCPA and CTB or infected with GAS M49 (5 x 10⁷) for three times at 1-week intervals and challenged with M49 (2 x 10⁸) 14 days after the last immunization or infection. CFUs in NALT were determined 24 hr after challenge. * <i>P</i> ≤ 0.05, **<i>P</i> ≤ 0.01, Kruskal-Wallis test.