Fig. 1.

T cells responses and protection against Mtb in different animal facilities. (A) Cytokine responses of T cells to antigen 85A. BALB/c mice were immunized with Ad85A i.d. or i.n. in an animal house with open top cages (OTC) or an animal house with individually ventilated cages (IVC). Lung and splenic lymphocytes were isolated 5 weeks post immunization and stimulated with pooled 85A peptides. The percentage of CD8+ cells expressing IFNγ was determined by flow cytometry. Error bars show SD. (B) Mtb growth after Ad85A i.d. or i.n. immunization in IVCs. In two experiments, BALB/c mice were immunized with Ad85A i.d. or Ad85A i.n. One month (B) or 8 months (C) later they were challenged with Mtb and lung CFU enumerated 5 weeks later. Data from the two experiments with 5–7 mice/group are shown. ***p < 0.001, **p < 0.01, *p < 0.05 from naïve or between the indicated groups, one-way ANOVA with Tukey's post test.