MODIFIED PROTOZOAN EXPRESSING AT LEAST TWO VARIABLE SURFACE PROTEINS (VSP), VACCINE COMPRISING THE SAME, PRODUCTION METHODS, APPLICATIONS AND METHODS OF USE

摘要

PROBLEM TO BE SOLVED: To provide modified parasite protozoa comprising simultaneous surface expression of more than one variable surface protein (VSP).SOLUTION: In a preferred embodiment, the protozoa comprise the simultaneous surface expression of the complete repertoire of variable surface proteins. The protozoa show a reduced expression of the Dicer (an enzyme cleaving small double-stranded RNAs), RNA-dependent RNA-polymerase (RdRP) or both, where the RdRP gene, the Dicer gene or a mixture thereof has been silenced. The protozoan may be any protozoa having an antigenic variation mechanism, where its antigenic variation mechanism may be unregulated by silencing any of its components.