Application of recombinant DNA techniques in the development of viral vaccines

The wide repertoire of methods developed for the construction and manipulation of recombinant DNA molecules enable viral genomes to be cloned and their genes expressed, in whole or in part, in microbial or animal cells in culture. This provides a ready source of many viral components that are otherwise difficult to obtain and in some cases were previously unknown. Although immediate applications for vaccine development have concentrated principally upon envelope proteins, the immunological importance of other viral components is being increasingly recognized. Hepatitis B virus is used here to exemplify the application of recombinant DNA technology to the development of subunit vaccines and to illustrate their value in studies of other viral proteins with particular emphasis on the role of the core antigen in providing protection against viral infection and hence its potential in vaccine development.