Ia requirement in T cell response to various mitogenic lectins

Various lectins, mainly T cell mitogens, were examined to determine the relationship between anti-Ia antiserum-treated T cell responses and the sugar specificities of these lectins. Anti-Ia antiserum and complement treatment diminished nylon wook column-purified T cell responses to most lectins such as concanavalin A, Lens culinaris hemagglutinin, Pisum sativum agglutinin, Witaria floribunda mitogen, Limulus polyphemus agglutinin and pokeweed mitogen, and the diminished response to these lectins could be restored by adding nylon wool-adherent cells, whereas the same treatment rather enhanced their response to Phaseolus vulgaris phytohemagglutinin. We concluded that whether t cell responses to various lectins require Ia-bearing cells more or less is independent of the sugar-binding specificities of these lectins.