ATTENUATION OF THE NYCBH VACCINE STRAIN OF VACCINIA

IN ORDER TO CREATE A VACCINE STRAIN ATTENUATED FOR VIRULENCETHREE STRAINS OF VACCINIA VIRUS THE NEW YORK CITY BOARD OF HEALTH VACCINE STRAIN AND TWO MORE VIRULENT DERIVATIVES, THEWESTERN RESERVE AND THE INTERNATIONAL HEALTH DEPARTMENT J STRAINS, WILL BE USED TO PREPARE RECOMBINANT VIRUSES DELETEDFOR SPECIFIC FUNCTIONS. THE GENES SELECTED FOR DELETION ENCODE FUNCTIONS THAT (1) ARE RESPONSIBLE FOR THE ABILITY OF THE VIRUS TO REPLICATE IN NONDIVIDING CELLS, (2) CONTRIBUTE TO THE MECHANISM OF VIRUS RELEASE FROM INFECTED CELLS, OR (3) ARE DEFINED BY A NATURALLY OCCURRING DELETION. THE PURIFIED RECOMBINANTS WILL BE ANALYZED FOR GROWTH IN TISSUE CULTURE AS EFFICIENT PARTICLE PRODUCTION WILL BE REQUIRED FOR SUBSEQUENT ANIMAL STUDIES AND COMMERCIALIZATION. CONCURRENTLY, THE THREE PARENTAL STRAINSWHICH DIFFER IN THEIR VIRULENCE, WILL BE UTILIZED TO INVESTIGATE THE ROLE OF DIFFERENT ROUTES OF INOCULATION IN INBRED STRAINS OF MICE AS THEY RELATE TO VIRAL SPREAD AND LETHALITY. THE PURPOSE OF THESE STUDIES IS TO DEVELOP A PERTINENT AND EFFICIENT ANIMAL MODEL SYSTEM IN ORDER TO ASSESS THE EFFECTSOF SPECIFIC GENOMIC ALTERATIONS ON THE VIRULENCE OF VACCINIAVIRUS. THE ULTIMATE GOAL IS TO PREPARE A SERIES OF STABLE ATTENUATED STRAINS FOR HUMAN VACCINE TRIALS.