INTERFERON DOSE RESPONSE CURVE AND ITS POSSIBLE SIGNIFICANCE

Although the literature and our unpublished data are compatible with the observation that a single molecule of interferon is sufficient to prevent a cell from producing virus progeny, slopes of dose response curves are often shallower (but not steeper) than those predicted for single-hit kinetics. We discuss possible explanations of how this may occur in three categories, either one interferon molecule may protect more than one cell, or the monolayer may contain cell types which respond differently to interferon, or there may be variation in sensitivity of viruses to the effect of interferons. In addition, an experiment is reported showing that cells infected in the absence of interferon can be prevented from producing plaques when seeded onto monolayers of interferon treated cells, although larger doses are needed than when the monolayers are seeded with virus. The slopes of the two dose-response curves are similar. Altogether these considerations suggest that a variety of circumstances operate to cause deviation from the expectation of the one term Poisson. © 1969.