TABLE 2.

Protection of BALB/cByJ mice passively immunized with anti-PspA serum

Challenge strainCapsule serotypePspA serotypeNo. of mice alive/ no. totalbPc
Without antibodyWith antibody
WU2310/1212/12<0.0001
MA10253250/55/50.0079
D392254/146/14NS
MA139/MA158a213/146/14NS
JD803/JD804a3256/147/14NS
  • a Data was combined for the two independently obtained derivatives, which did not differ from each other.

  • b Mice were infected intravenously with 107 CFU 1 h after intraperitoneal immunization with anti-PspA polyclonal antiserum (with antibody) or a control antiserum lacking PspA-specific antibody (without antibody).

  • c Calculated by using Fisher's exact test. NS, not significant.