Use of the Microparticle Nanoscale Silicon Dioxide as an Adjuvant To Boost Vaccine Immune Responses against Influenza Virus in Neonatal Mice.

Vaccines can fail to protect the most at-risk populations, including the very young, the elderly, and the immunocompromised. There is a gap in neonatal immunity between the waning of maternal protection and routine infant immunization schedules, exacerbated by the failure of vaccines to work in the first months of life. One approach is to design age-specific formulations, with more-effective adjuvants, based on our understanding of the nature of the neonatal immune response. We chose to target the inflammasome, a molecular complex capable of detecting infection and cell damage and of triggering IL-1β-driven inflammation. We screened a range of compounds in vitro and in vivo and identified three lead candidates: NanoSiO2, CPPD, and M-Tri-DAP. Of these, NanoSiO2 was the most effective and boosted the anti-influenza virus response in both adult and neonatal mice. This finding is important for the development of age-specific vaccines, designed using our knowledge of the neonatal immune response.