[Specificity of interactions between thymus-dependent lymphocytes and influenza viruses (author's transl)].

Destruction of influenza virus-infected target cells by cytotoxic, thymus-derived lymphocytes (CTL) and the measurement of this reaction with an 51Cr-release assay is a practicable model for studying the complicated interactions between influenza viruses and T-lymphocytes. There is abundant evidence that T-cell-mediated lysis of influenza virus-infected target cells generally requires the H-2K or H2D region histocompatibility between CTL and target cells. Two general explanation have been proposed to account the requirement of the H-2 compatibility between lymphocytes and virus-infected target cells, the "altered self" concept and the "dual recognition" hypothesis. The specificity of the cytotoxic response against influenza viruses is dependent on the viral haemaglutinin. A second, cross-reactive subpopulation of CTL recognized furthermore the M protein as the traget antigen. The role of the target cells in determining the specificity of the CTL response is therefore of special importance for the infectivity of the influenza viruses.