IL17A and infection: By day 2 of infection, significant fold increases above background in the mean levels of IL-6 (40–55-fold), IL-17 (9–14-fold), KC (8–11-fold), MCP-1 (10–14-fold), and RANTES (2–4-fold) were observed in lung homogenates from all vaccinated groups, but not unvaccinated control mice.