Table 2.

Anti-PT IgG levels in serum and lungs at time of challenge

ImmunizationaAntibody titerb (mean ± SE)
Pw active1,600 ± 20NTc
Pw passive1,587 ± 5040 ± 20
Pa active12,800 ± 410NT
Pa passive10,413 ± 1,400320 ± 50
  • a Mice were immunized as described in the legend to Fig. 6, and serum and lung lavage samples were recovered from groups of four mice 2 weeks after active immunization or 4 h after passive immunization.

  • b Mean reciprocal endpoint titer (based on 1.0 ml of lavage fluid for lungs) for four mice in each experimental group.

  • c NT, not tested.