Evaluation of a Western Equine Encephalitis recombinant E1 protein for protective immunity and diagnostics.

The E1 and E2 glycoproteins of Western Equine Encephalitis (WEE) are candidate antigens for WEE subunit vaccine development. We have cloned the E1 gene of WEE virus and expressed it in Escherichia coli as inclusion bodies. The inclusion bodies were successfully solubilised, refolded and the immunogenicity of this unglycosylated protein was assessed in mice. Immunization of mice with recombinant E1 protein generated both humoral and cell-mediated immune responses, indicating the recombinant E1 protein is immunogenic. Challenge of E1-immunized mice with live WEE virus demonstrated little or no protection from this E. coli-derived non-glycosylated subunit.