Figure 4.
The MAYV/IRES attenuated vaccine strain is associated with reduced production of inflammatory mediators in vivo, and upon antigen stimulation ex vivo. 6-week-old BALB/c mice were inoculated either wt MAYV or MAYV/IRES (2 × 105 PFU/50 μL, i.pl.) and levels of (a) IL1-β; (b) IL-6; (c) IFN-γ; (d) TNF-α; (e) VEGF; (f) IL-17; (g) IL-10; (h) CXCL-1; (i) CCL2; (j) CCL3; (k) CCL4 and (l) CCL5 in the spleen were measured in different time-points. Results are expressed as pg/100 mg of spleen. (m–p) Ex vivo stimulation of splenocytes isolated from MOCK-, wt MAYV-, and MAYV/IRES-inoculated mice 28 d.p.i. Splenocytes were then re-stimulated with 2 μg/mL ConA, inactivated wt MAYV or inactivated MAYV/IRES. Cell supernatants were harvested after 48 hours of stimulation for cytokine (m) IFN-γ; (n) IL-17; (o) TNF-α and (p) IL-10 measurements as described in methods. Results are expressed as pg/100 mL of culture supernatant. Data is representative of two experiments expressed as mean ± SEM. *p < 0.05 when compared to control uninfected cells (MOCK). #p < 0.05 when compared to wt MAYV stimulated cells, as assessed by one-way ANOVA followed by Newman-Keuls post-test. ND, not detectable.