Development and evaluation of granules containing Lactobacillus harboring EV71’s cellular receptor

Hand, foot and mouth disease (HFMD) is a common viral disease characterized by symptoms including fever, painful sores and rashes. The disease is mostly mild and occurs mainly in children under 10 years old, but can also appear in adolescents and adults. The dominant cause is a group of enteroviruses including Coxsackie A16 and Enterovirus 71 (EV71). Particularly HFMD caused by EV71 can cause severe symptoms in children and has been associated with complications such as meningitis and encephalitis. There has been a significant increase in EV71 epidemic activity throughout the Asia – Pacific region since 1997. There is no specific prevention – including a vaccine – available for HFMD until now, and hundreds of thousands of cases are reported annually, putting a burden on society. Several significant milestones in vaccine development have been reached recently; in contrast to that, there has been little progress on preventive approaches like blocking virus entry to targeted cells. Such approaches are cost-effective for resource-limited countries but the drug’s effectiveness is highly dependent on the timing of the treatment. We will pursue a strategy to block the entry of the virus to its cellular receptor. Human scavenger receptor class B member 2 (hSCARB2) is a cellular receptor for EV71 and CVA16. The region from amino acids 142 to 204 has been shown to be important for EV71 binding and infection, and there are no potential N-glycosylation sites in that region. Recently, E. coli derived, soluble, recombinant SCARB2 has been shown to interact with EV71 in vitro. However, whether the recombinant SCARB2 blocks EV71 infection in vivo remains elusive. In order to use recombinant SCARB2 as a preventive reagent in humans, the receptor has to be used in non GMO or food-grade format. Our research project is focusing on producing recombinant SCARB2 and attaching it onto Lactobacillus plantarum cell membranes using LysM domains, or by directly expressing it in L. plantarum, to use as a bait to prevent virus infection and spreading.