Immune processes in the course of infection with dysentery bacilli. I. Transfer of immunity by means of spleen cells.

Studies on the mechanisms of immune phenomena in the course of infections with dysentery bacilli in mice showed that injection of live Shigella sonnei phase I bacilli intravenously evokes the appearance in the spleen of cells by means of which immunity to a lethal dose of these microorganisms can be transferred into other mice. Immunity to a lethal dose of the bacteria was measured by the number of animals surviving the infection, and by the numbers of bacteria isolated from the organs of the animals. "Active" cells appeared in the spleen 4-8 days after immunization. Spleen cells obtained from mice earlier than 4-8 days after immunization, or from non-immunized mice, were inactive. The role of cell-mediated immunity, reactivity to endotoxins per se, and specific immunoglobulins in immunity to bacterial dysentery in mice are discussed.