Fig. 4.
Strong NK cell activation and functionality upon systemic rMVA-CD40L immunization. a Systemic mobilization of NK cells upon intravenous rMVA immunization. C57BL/6 mice received PBS (n = 2 mice) or were immunized i.v. with 5 × 107 TCID50 of either rMVA or rMVA-CD40L (n = 3 mice/group). Mice were killed at days 1 or 4 after immunization and the presence of NK cells (defined as CD3- NKp46+ cells) in the spleen, blood, liver, and lung was assessed. Data are expressed as mean ± SEM, representative of two independent experiments. b, c rMVA or rMVA-CD40L induction of NK cell activation. C57BL/6 mice received PBS (n = 2 mice) or were immunized i.v. with 5 × 107 TCID50 of either rMVA or rMVA-CD40L (n = 3 mice/group). Mice were killed at day 1 after immunization and the expression of CD69 (b) and IFN-γ (c) on splenic NK cells was analyzed by flow cytometry. Data are expressed as mean ± SEM, representative of two independent experiments. d, e Activation of splenic- and tumor-infiltrating NK cells upon rMVA-CD40L immunization. B16.OVA tumor-bearing mice (n = 5 mice/group) received PBS or were immunized i.v. with 5 × 107 TCID50 of rMVA-CD40L. Mice were killed at day 2 after immunization and the presence of NK cells (d) as well as the expression of CD69 (e) and IFN-γ (f) on NK cells infiltrating the spleen and tumor was assessed by flow cytometry. Data are expressed as mean ± SEM, representative of two independent experiments. Two-way ANOVA was performed on a and d–f. **p < 0.01; ***p < 0.005