TABLE 2

Number of immunizations required to protect mice against syringe inoculation with B. burgdorferia

ImmunogenNo. of immunizationsChallenge strainNo. of tissue samples culture positive/totalNo. of mice protected/total
PBS-NMS2B31-A322/250/5
Δp66 bacteria2B31-A38/25b2/5c
p66cp bacteria2B31-A39/25b1/5c
PBS-NMS3B31-A324/250/5
Δp66 bacteria3B31-A30/25b5/5d
p66cp bacteria3B31-A31/25b4/5e
PBS-NMS4B31-A324/250/5
Δp66 bacteria4B31-A30/25b5/5d
p66cp bacteria4B31-A30/25b5/5d
  • a All mice were challenged 4 weeks after the last boost with 1 × 105 B. burgdorferi B31-A3 bacteria via subcutaneous injection. Mice were euthanized 2 weeks after the bacterial challenge. In each group, Δp66- or p66cp-immunized mice were compared to the PBS-NMS-treated controls with Fisher's exact test in GraphPad Prism. No statistical information is provided for the PBS-NMS group compared to itself.

  • b P < 0.0001.

  • c No statistically significant difference.

  • d P < 0.01.

  • e P < 0.05.