Pre-existing immunity to norovirus GII-4 virus-like particles does not impair de novo immune responses to norovirus GII-12 genotype

摘要

Noroviruses (NoVs) are one of the leading causes of acute nonbacterial gastroenteritis in humans of all ages. In the 1990s, NoV genotype GII-4 became responsible for the majority of NoV sporadic gastroenteritis cases and outbreaks worldwide. Vaccine development against NoV GII-4 is underway. At the same time, there is concern of new emerging NoV genotypes, such as GII-12, which has been recently associated with increasing numbers of NoV outbreaks worldwide. The specific question is whether type-specific pre-existing immunity to NoV GII-4 might impair cognate immune response induced by new viral infections or vaccines. Using GII-4 and GII-12 virus-like particles, we tested the impact of the immunity generated against NoV GII-4 on de novo antibody responses to GII-12 in mice. We found that pre-existing immunity to NoV GII-4 did not impair de novo immune response to the novel antigen, therefore suggesting lack of original antigenic sin (OAS).