Figure 3.
Caspase-1 dependent increase of IL-1β and IL-18 secretion in mice infected with SFTSV. Five-week-old C57BL/6 mice (male) were infected with SFTSV (1 × 105 PFU) and measurement of IL-1β secretion and viral load in mouse sera was carried out at day 0, 2, 4, 6 and 8 p.i. Viral RNA copy numbers in the blood were determined by extraction of total RNA from the whole blood and RT-PCR with specific primers for the viral S genomic segment, while serum IL-1β levels by ELISA. (A) Viral RNA copy numbers and (B) IL-1β levels in the sera of the mice infected with SFTSV. C57BL/6 WT mice (5 weeks old, male) were pretreated with DMSO or Ac-YVAD-cmk (8 mg/kg) by intraperitoneal injection and then infected with SFTSV (1 × 105 PFU) or with PBS. At each time point, on day 0, 2, 4, 6, and 8 days p.i., six mice from the Ac-YVAD-cmk or control group were sacrificed, and viral RNA copy numbers in the blood were determined by RT-PCR (C). The levels of IL-1β, IL-18 and IL-6 in mouse sera were determined by ELISA (D–F). Data shown were whiskers: min.-max.; *P < 0.05, ***P < 0.01, ***P < 0.001 (one-way ANOVA with SNK post-hoc test).