Purified flagella from Treponema phagedenis biotype Reiter does not induce protective immunity against experimental syphilis in rabbits.

Thirteen rabbits were immunized three times at weekly intervals with 50 micrograms of flagella purified from Treponema phagedenis biotype Reiter. Fourteen rabbits were inoculated in the same way with a placebo preparation. Rabbits immunized with the flagella developed an immune response to the flagella but showed no statistically significant prolongation of incubation time or diminution of lesion severity when challenged intradermally with 4 X 10(3) Treponema pallidum organisms.