Rotavirus VP6 as a potential vaccine candidate.

By the age of 5 years, virtually all children have been infected by group A rotavirus (RVA), which is responsible for around half million mortality annually prior to vaccination. Relatively high rate of the morbidity and mortality highlights the necessity of applying preventive procedures particularly in developing countries. Two live attenuated RVA vaccines (Rotarix and RotaTeq) are licensed and now being used in many countries worldwide. Although these vaccines are shown to reduce the mortality up to 50%, several key questions yet remained to answer. Indeed, the licensed RV vaccines were found to be less effective in countries of sub-Saharan Africa and Southeast Asia. Therefore, developing next generation RVA vaccines is warranted. VP6 is highly abundant and conserved protein that forms the middle layer of RV particles and was shown to be both antigenic and immunogenic. Although it does not induce neutralizing antibodies, different VP6 preparations were found to induce homologous and cross-reactive immune responses with partial protection from RVA replication. Although the molecular mechanisms are not fully elucidated, VP6-based RVA vaccine candidates are worthy of further consideration. This review aims to focus on different aspects of VP6 protein and its potentiality for an alternative RV vaccine against RV disease.