ΔmotB strain infectivity in mice via needle inoculationa

StrainDosebReisolation from tissues (no. of specimens positive/total no. examined)No. of infected mice/total no. challenged
WT3 × 1032/44/44/44/4
ΔmotB5 × 1030/40/40/40/4
ΔmotB3.75 × 1060/40/40/40/4
motBcom3.4 × 1033/44/44/44/4
  • a C3H/HeN mice were injected intradermally using the indicated in vitro-grown spirochete clones. Mice were sacrificed 3 weeks postinoculation, and infectivity was determined by reisolation or detection of B. burgdorferi genomes by PCR from sacrificed mouse tissue samples.

  • b The number of spirochetes injected per mouse was calculated by direct counting of bacteria using a Petroff-Hausser chamber. The calculated inocula were plated to verify the CFU, and doses shown are the actual CFU injected per mouse.