摘要 |
<p>A vaccine against a RNA virus, which may be a picorna virus, an orthomyxovirus or a retrovirus, is prepared by infecting host cells with the virus, incubating the infected cells for a time and at a temperature which is insufficient to result in lysis of the cells, separating the nuclei of the cells intact from their cytoplasmic fraction, and stabilizing viral antigenic proteins in the cytoplasmic fraction, the stabilized proteins providing the active constituent of the vaccine.</p> |