[Gene technology in the diagnosis of viruses and vaccine development].

The development of genetechnological methods since the beginning of the 1970's allowed the molecular cloning of partial or complete viral genomes and the sequencing of their nucleic acids. On this basis, new tools for viral diagnostics are available: molecular probes for hybridization techniques and synthetic peptides or highly purified proteins for the specific detection of antibodies. While the role of synthetic peptides as vaccines seems to be limited, complete viral surface proteins produced by gene technological methods are already used for vaccination in man. The advantages and disadvantages of production in bacteria, in yeast and in higher eukaryotic cells of polypeptides designed as subunit vaccines are discussed. An additional, attractive model is the synthesis of antigens immediately in the host, directed by a recombinant vaccinia virus. Another promising approach is the establishment of potent and safe live vaccines by the introduction of defined mutations or deletions into a viral genome, based on the previous elucidation of the molecular mechanism of attenuation.