Cellular cytotoxicity mediated by guinea pig lymph node cells was induced by use of various lectins and mitogens. T cell mitogens (phytohemagglutinin, concanavalin A, Wisteria floribunda mitogen, Pisum sativum agglutinin, and Lens culinaris agglutinin) and two nonmitogenic lectins (type 1 nonmitogenic lectins; Bauhinia purpurea agglutinin and soy bean agglutinin) were capable of inducing marked lectin-induced cellular cytotoxicity (LICC). On the other hand, the other nonmitogenic lectins (type 2 nonmitogenic lectins; Sophora japonica agglutinin, Ulex europeus agglutinin, and peanut agglutinin) and B cell mitogens (bacterial lipopolysaccharide and a purified protein derivative) were weak inducers of LICC.SUMMARY
A positive correlation was found between the LICC-inducing activity of the lectins and the mitogens and their activity to induce the release of guinea pig lymphotoxin (GLT) into the supernatant of the LICC culture. Furthermore, LICC by various lectins and mitogens was inhibited by anti-GLT serum regardless of the type of lectin or mitogen.SUMMARY
The cellular cytotoxicity induced by T cell mitogens or type 1 nonmitogenic lectins was found to be mediated by nylon-nonadherent cells, whereas that induced by type 2 nonmitogenic lectins or B cell mitogens was not mediated by these cells. These results suggest that at least two different effector cell populations are operative in LICC and the effector molecule is GLT regardless of the type of lectin or mitogen used.