TNFα and IFNγ but Not Perforin Are Critical for CD8 T Cell-Mediated Protection against Pulmonary Yersinia pestis Infection
Figure 4
TNFα and IFNγ are critical for T cell-mediated protection against Y. pestis.
(A and B) Wild-type (WT), TNFα-deficient (TNFaKO), IFNγ-deficient (IFNgKO) C57BL/6 mice were immunized intranasally with CT adjuvant alone or CT mixed with YopE69–77 peptide and then challenged intranasally with 20 MLD Y. pestis strain D27. In comparison with YopE69–77–immunized WT mice (n = 15–25), YopE69–77–immunized TNFα-deficient (n = 22) and IFNγ-deficient (n = 18) mice exhibited significantly reduced survival. Data were pooled from 3–5 independent experiments. (C) Wild-type C57BL/6 mice were immunized intranasally with CT alone or CT mixed with YopE69–77 peptide and then challenged intranasally with 20 MLD Y. pestis strain D27. One day before the challenge, the YopE69–77-immunized mice received neutralizing mAb specific for TNFα (anti-TNF), IFNγ (anti-IFN), or an isotype-matched mAb (Ctrl Ig). In comparison with CT-immunized mice (n = 20), YopE69–77-immunized mice treated with isotype-matched mAb (n = 19) or IFNγ-neutralizing mAbs (n = 10) but not TNFα-neutralizing mAb (n = 20) were protected against Y. pestis challenge. Data were pooled from 4 independent experiments.