Table 4.
Infectivity of B. burgdorferi expressing vlsE and ospA from the flaB promoter
| B. burgdorferi strain | No. of infected mice/ no. of mice injecteda | |
|---|---|---|
| WT | SCID | |
| WT | 9/10 | 10/10 |
| WT/pFpvlsE1 | 4/5 | 3/5 |
| WT/pFpospA | 2/5 | 5/5 |
| ΔospC | 0/10 | 3/10 |
| ΔospC/pFpvlsE1 | 0/5 | 0/5 |
| ΔospC/pFpospA | 0/5 | 5/5b |
a
Both immunocompetent WT mice and immunodeficient C3H-SCID mice were injected intradermally with 104 organisms of the designated B. burgdorferi strain. At three weeks post-injection, WT mice were retro-orbitally bled to test by immunoblot for seroconversion to B. burgdorferi proteins, and all mice were euthanized for attempted isolation of spirochaetes from the ear, bladder, and tibiotarsal joint. All seropositive WT mice were also positive for isolation from all three tissues.
b
The number of SCID mice infected by the ΔospC/pFpospA strain was significantly different from that of ΔospC (P = 0.026, as determined by Fisher's two-tailed exact probability test).