Group B Streptococcus Induces a Robust IFN-γ Response by CD4⁺ T Cells in an In Vitro and In Vivo Model

Figure 1

Survival curves and bacteremia levels of GBS-infected C57BL/6 mice. (a) Mice () were injected intraperitoneally with different doses of wild-type GBS serotype III strain COH-1 and survival levels recorded. Mock-infected animals (injected with the vehicle solution) were used as controls. (b) Systemic bacteremia levels of infected mice were monitored at 18 h after infection (for mice infected with 10⁶, 10⁷, and 10⁸ CFU) and at 72 h after infection (for mice infected with 10⁶ CFU). Blood was drawn by tail puncture and serially diluted in PBS prior to plating on blood agar dishes. Individual colonies were counted and data expressed as CFU/mL of blood. , compared to higher infectious doses.

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