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The method described in the previous paper was used to induce secondary responses in spleen cells from CBA/H mice, pre-primed with lymphocytic choriomeningitis (LCM) virus by culturing them with LCM-infected peritoneal cells. The cytolytic effector cells thus generated have been characterized. Effector cells were sensitive to treatment with anti-θ ascitic fluid and complement. Separation procedures based on rosetting of certain categories of lymphocytes with sheep red cells through an isopaque-Ficoll gradient indicated that effector cells lacked surface immunoglobulin and generally did not bear Fc receptors. Cytolytic activity was restricted by the H-2 gene complex. Killing had single-hit characteristics. All these results suggested that the cells from memory cultures mediating cytolysis were T cells. There was evidence for two T cell subsets, a major subpopulation directed against antigens on infected targets and a minor one directed against antigens on uninfected, H-2-compatible targets. Specificity was present at the infected cell: memory responder and killer:target levels between LCM virus (an arenavirus) and ectromelia virus (a poxvirus). [ABSTRACT FROM AUTHOR]

Infection of cells with either ectromelia or lymphocytic choriomeningitis (LCM) virus in the presence of 2-deoxy-D-glucose (2-DOG) inhibited by up to 70% the extent to which the infected ceils become susceptible to virus-specific cell-mediated lysis. The concentration of 2-DOG used had little effect on the extent of total protein synthesis (incorporation of [35S]methionine) but inhibited (up to 25%) glycoprotein synthesis, as measured by incorporation of [³H]fucose. This suggested that glycoprotein synthesis was a necessary event for infected cells to become susceptible to T-cell-mediated lysis. The profiles (polyacrylamide gel electrophoresis) of newly synthesized, cellular glycoproteins from uninfected and ectromelia-infected cells in the presence and absence of 2-DOG were compared and found to be very complex, with only minor changes. However, when convalescent serum from infected mice was used to isolate newly synthesized components from the cell surface shortly after infection, it showed four main species ranging in size from 25,000 to 70,000 daltons. 2-DOG inhibited production of these by 70%, thus corresponding to the biological data. The nature of the new glycoproteins seen in infected cells and whether they are in fact the structures recognized by effector T cells remain to be determined. [ABSTRACT FROM AUTHOR]