RECOMBINANT VACCINIA VIRUS EXPRESSING PRM-GLYCOPROTEINS AND E-GLYCOPROTEINS OF LOUPING ILL VIRUS - INDUCTION OF PARTIAL HOMOLOGOUS AND HETEROLOGOUS PROTECTION IN MICE

Recombinant vaccinia viruses expressing either the premembrane/truncat ed envelope (PrM/TrE) or truncated envelope (TrE) protein of louping i ll virus were constructed. Both constructs expressed authentic E prote ins as determined by their size and antigenic reactivity with a panel of monoclonal antibodies. The deletion of the C-terminal hydrophobic d omain of the envelope glycoprotein resulted in the secretion of E prot ein into the supernatant culture medium. The immunisation of mice with these recombinant viruses showed that the recombinant expressing PrM/ TrE proteins induced neutralising and protective antibodies against ch allenge with louping ill or tick-borne encephalitis virus, but that th e recombinant expressing the E or the TrE protein alone failed to indu ce any detectable immune responses against homologous or heterologous virus challenge.