A technique is described for collecting separately the secretion of the parotid gland and the combined secretions of the submaxillary (SM) and sublingual (SL) glands.
The SM-SL secretion from a given individual has a lower nitrogen content than parotid secretion but exerts a higher inhibitory activity against hemagglutination by influenza virus A (PR8 strain) or swine influenza virus. The inhibition is based on a reaction between inhibitor and virus. The SM-SL inhibitor is fairly thermostable, about 30 per cent remaining after 40 minutes at 100 C. The inhibitor is destroyed by unheated virus but not by virus heated for 30 minutes at 53 C. Heated virus is more susceptible than unheated virus to inhibition.
The SM-SL secretion also contains an agglutinin for chicken RBC; this factor is typically absent from parotid secretion. The hemagglutinin appears to be a factor distinct from the salivary inhibitor since the titers of the two are not correlated and since the hemagglutinin can be selectively absorbed out with RBC and selectively neutralized with traces of heparin.
This work was supported by a research grant from the National Cancer Institute, U. S. Public Health Service; by a grant to Duke University from Lederle Laboratories, Inc., Pearl River, N. Y.; and by the Dorothy Beard Research Fund.