Developmental Study Relating to the Preparation of a Respiratory Syncytial Virus Vaccine

摘要

Synopses of the release protocols relating to the preparation and safety testing of five live virus pools for use in human volunteer studies are presented. Techniques for producing macroplaques of RS viruses in primary AGMK and canine kidney petri dish cultures under agarose are described. The production of infectious RS fluids in different tissue culture systems for use in concentration and purification procedures is summarized. Studies on the effects of the virus/cell ratio in various tissue culture systems indicated no significant differences in yields of CF and/or infectious virus. In vivo quantitative tests for measurement of immunogenic potency are presented and include studies on the adaptation of the Maassab strain of RS virus to the CNS of newborn and 9-day old mice; intranasal infection of weanling hamsters with the subsequent determination of viral content in lungs and trachea; comparative antibody responses of guinea pigs to live and dead RS virus vaccines. In vitro quantitative tests for measurement of antigens and antibodies are described and include a microtissue culture system and the standardization of the 'accessory' factor employed as an aid in the serum-neutralization test. The zinc method for virus concentration was studied. Evidence is presented that the RS immunogen probably resides in the sedimentable fraction. Zinc-EDTA but not zinc alone appears to have some stabilizing effect on RS virus on storage at 4C. Studies indicate that protein precipitation by the zinc method is more directly related to the nature of the protein rather than on the concentration of the zinc employed. Various metods of RS CF antigen concentration are compared as the preliminary step towards preparing large amounts of purified RS immunogenic reagents. (Author)