Interferon γ Enhances Both In Vitro and In Vivo Priming of CD4+ T Cells for IL-4 Production

Abstract
The results of mouse protection tests with 136 human sera and a strain of human influenza virus are described. After the 1st year of life, the sera of approximately half the individuals tested contained sufficient antibody to furnish complete protection to mice. A much higher percentage of the sera obtained from individuals recently convalescent from influenza exerted a completely protective effect. On the other hand, certain sera protected only partially under the conditions of the tests.