A test for the
lymphokine eosinophil stimulation promoter (ESP) has been adapted to the study of Trichinella spiralis
infections in mice and has been used as an aid in the diagnosis of
trichinosis in a patient. With use of soluble
antigen extracted from T. spiralis larvae and peritoneal exudate cells rich in eosinophils obtained from mice with
trichinosis of four weeks' duration, a dose-response curve was constructed and analyzed. The soluble larval
antigens greatly enhanced the migration of eosinophils from the mice with
trichinosis but had no effect on the eosinophils from mice with
schistosomiasis, nor did soluble schistosome egg
antigens have any effect on the cells from mice with
trichinosis. On two occasions peripheral white blood cells from a patient with presumed T. spiralis
infection gave strongly positive results in ESP tests on stimulation with soluble larval
antigen, but the cells did not respond significantly to soluble schistosome egg
antigen; the result in the ESP test was positive before the patient's serum produced a weakly positive agglutination response.