FIG. 2.

Serum anti-TTFC IgG1 and IgG2a titers elicited by recombinant lactococci or purified TT. Groups of six mice were immunized, either i.g., i.n., or by i.p. injection, with lactococci expressing TTFC (pTREX1-TTFC) or a control strain (pTREX1). For comparison, a group of mice was injected with TT in FCA, while another group received no treatment. On day 35 post-initial treatment, blood samples were collected, and serum TTFC-specific IgG1 (open bars) and IgG2a (solid bars) titers were measured by ELISA. Bars, mean titers; error bars, standard deviations. Asterisks indicate values significantly different from those for nonvaccinated controls (P < 0.05).