Long-term regulation of local cytokine production following immunization in mice

Vaccines based on pathogen components require adjuvants to enhance the antigen-specific adaptive immune response. Intramuscular injection of adjuvanted-vaccines induces inflammatory cytokines and inflammatory nodules at the injection site within 48 hr after injection (Vaccine 2014; 32: 3393-401). In the present study, long-term regulation of cytokine production was investigated at 3, 6, 24, and 48 hr, 5 and 7 days, and 2 and 4 weeks after immunization with human papilloma virus (HPV), diphtheria and tetanus toxoids combined with acellular pertussis (DTaP), Haemophilus influenza type B (Hib), and pneumococcal conjugated (PCV) vaccines in mouse models. The second dose was given 4 weeks later, and cytokine profiles were investigated 2, 5, and 7 days after re-immunization. IL-1β, IL-6, granulocyte-colony stimulating factor (G-CSF), and MCP-1 were produced from 3 hr and peaked at 48 hr after immunization with Cervarix in mice. IL-4, MCP-1, and TNF-α peaked at 5 or 7 days after immunization with Gardasil. These cytokines decreased 7 days after immunization with Cervarix and Gardasil. After the second dose, similar responses were observed. Both vaccines induced neutrophil extracellular traps (NET) in inflammatory nodules. The peak amount of IL-1β, IL-6, G-CSF, and MCP-1 was observed on day 5 of immunization and that of IL-4 on days 5-7 of immunization with DTaP, but no increase in IL-6 and G-CSF was observed after re-immunization. A similar response was noted after immunization with PCV13. An inflammatory response is essential for the development of adaptive immunity through the production of inflammatory cytokines.