[Secretory immunoglobulins and serum antibodies after oral infection of the white mouse with Salmonella typhimurium (author's transl)].

White Mice were infected via the gastrointestinal tract with S. typhimurium. The immunoglobulin class of specific antibodies appearing in serum and intestinal secretions was determined. Specific antibodies were detected as early as 7 days after infection in the intestinal secretions, and reached maximum titers on day 21. These antibodies belonged exclusively to the IgA class. After day 21, at a time when serum antibodies had reached high titers, antibodies of the IgG class were also detectable in the gut in low levels. Specific antibodies of the IgM class could never be demonstrated in intestinal secretions. Antibody titers remained at almost constant levels over the entire test period of 92 days in those animals with Salmonella in their intestine. In animals, where Salmonella were no longer demonstrable in the gut, antibody titers decreased. Serum antibodies could first be detected 12 days after infection. They reached maximum titers between day 21 and 36. Until day 21 equal levels of IgG and IgM antibodies were found. Later on, antibodies of the IgG class predominated. In Salmonella carriers antibody titers remained on high levels over the entire test period. In animals negative for S. typhimurium in liver and spleen, antibody titers declined until the end of the test period. A new and simple method for raising a class-specific anti-mouse IgA Antiserum by immunization of rabbits with IgA from washings of the small intestine is described.