Patent ID: 6592873
Filing Date: 2003-07-15
Classification: A61K,A61P,C07K,C12N,G01N

Abstract:
A method of producing an immunogenic composition, comprising the steps of(a) introducing a purified preparation containing a polynucleotide encoding at least one polypeptide encoded by one or more open reading frames (ORF's) of ORFs 1-7 of a porcine reproductive and respiratory syndrome virus (PRRSV) wherein the PRRSV is characterized as highly virulent as determined by its ability to induce lesions in at least 51.9% of lung tissue 10 days post-inoculation of five-week-old colostrum-deprived, caesarean-derived pigs with 105 TCID50 of said PRRSV into a suitable host cell by either (i) transfecting the cells with the polynucleotide or infecting the cell with a virus comprising the polynucleotide; (b) culturing said host cell; and (c) isolating one of the following: (i) the infected or transfected host cell; (ii) virus; (iii) viral protein; (iv) viral polynucleic acid; or (v) mixtures thereof.