cDNA corresponding to the antigenome of nonsegmented negative stranded RNA viruses and process for the production of such viruses

A method for producing an infectious non-segmented negative-strand RNA virus of the family Paramyxoviridae comprising:

• (a) introducing into a host cell a plasmid comprising a cDNA molecule, said cDNA molecule comprising a (i-)-strand sequence of said negative-strand RNA virus, encoding the entire genome of the virus, operatively linked to an expression control sequence, which allows the synthesis of antigenomic RNA transcripts bearing the authentic 3′-termini, wherein the (+)-strand sequence of said negative-strand RNA virus is operatively linked to a foreign expressible DNA fragment and wherein the length of the genome of the infectious non-segmented negative-strand RNA virus is an integral multiple of six, said host cell comprising (i) stably transfected nucleic acid molecules containing nucleic acid sequences that allow genomic expression of an exogenous RNA polymerase, a viral N protein and a viral P protein, and (ii) a nucleic acid molecule containing nucleic acid sequence encoding a viral L protein;
• and
• (b) recovering the infectious non-segmented negative-strand RNA virus without the help of a helper virus.