Aquanititave semimicro, semiautomated colorimetric assay for interferon.

The colorimetric assay for interferon, which utilizes a vital dye uptake for determination of cell viability, was adapted for semimicro quantities of cells and reagents and semiautomated techinques. Factors affecting interferon titer included the duration if interferon treatment of cells prior to viral challenge, the multiplicity of viral challenge, and the number of viral replicative cycles. Only the multiplicity of the volume, of the interferon sample determined final titer, emphasizing that introduction of a volume term in a statement of interferon titer expresses interferon mass. The semimicroassay for interferon in both human and mouse cells proved precise, sensitive, convenient, reliable, and relatively simple and rapid.