Assessment of Ab responses and protection in mice immunized with recombinant BVH-3 and BVH-11 antigens and chimeric CH-3C-11B protein or its respective counterparts. (A, B, and C) Flow cytometry analysis showing surface Ab binding to live pneumococci. Each square on the x axis represents units from 100 to 104, whereas the maximum cell number on each y axis is 64. (D, E, and F) Protection elicited against heterologous challenges with strain WU2 in a sepsis model of infection (D) or with strain P4241 in a pneumonia model of infection (E and F).