LAP + Cells Modulate Protection Induced by Oral Vaccination with Rhesus Rotavirus in a Neonatal Mouse Model

Despite the introduction of several live attenuated animal and human rotaviruses as efficient oral vaccines, rotaviruses continue to be the leading etiological agent for diarrhea mortality among children under 5 years of age worldwide. Improvement of these vaccines has been partially delayed because immunity to rotaviruses is incompletely understood. In the intestine (where rotavirus replicates), regulatory T cells that express latency-associated peptide (LAP) play a prominent role, which has been explored for many diseases but not specifically for infectious agents. In this paper, we show that neonatal mice given a live oral rotavirus vaccine develop rotavirus-specific LAP + T cells and that depletion of these cells improves the efficiency of the vaccine. These findings may prove useful for the design of strategies to improve rotavirus vaccines.