Figure 15.

Summary of the immune response components indispensable to the control of secondary Brucella infection as a function of the route of infection. Wild-type, CD3^−/−, TCRαβ^−/−, TCRγδ^−/−, MHCII^−/−, TAP1^−/−, MuMT^−/−, IL-12p35^−/−, and IL-17RA^−/− C57BL/6 mice were infected intradermally (i.d.), intranasally (i.n.) or intraperitoneally (i.p.) with 2 × 10⁴ CFU of live wild-type B. melitensis and treated with antibiotics, as described in the Materials and Methods. Naive (primary infection group) and immunized (second infection group) mice were challenged i.d., i.n., or i.p. with 2 × 10⁴ CFU of live mCherry-B. melitensis and sacrificed at 12 days post infection (for i.d.) or 28 days post infection (for i.n. and i.p.). The data represent a qualitative approximation of the CFU count per organ in the present article (i.d. model and Figure S8 for i.p. model) or in our group's previous article characterizing the i.p. (20) and i.n. (21) models. The CFU counts of mice which do not control the secondary infection are in red. “/”, not tested. Note that “Th1 or Th17” indicates that the Th1 response can compensate for the absence of the Th17 response and vice versa.