Reduction of yellow fever virus mouse neurovirulence by immunization with a bacterially synthesized non-structural protein (NS1) fragment.

Part of a yellow fever virus-specified non-structural protein (NS1) was expressed in Escherichia coli as a fusion protein with beta-galactosidase. Immunization of mice with this partially purified NS1-beta-galactosidase fusion protein induced yellow fever virus-specific antibodies and provided some protection against intracerebral challenge with the virus.