Search

Antieosinophil serum (AES), obtained by immunizing rabbits with a highly purified suspension of mouse eosinophils, contains high titers of specific agglutinating and cytotoxic antibodies to eosinophils. Absorption with macrophages, lymphocytes, and neutrophils does not affect the antieosinophilic activity while it is markedly lowered by absorption with eosinophils. One dose of AES (0.1 ml) injected into mice with schistosomiasis mansoni caused a mean decrease in circulating eosinophils of 90% within 1 h which was maintained for 5 days, followed by gradual recovery. No other changes in the total or differential white cell counts were noted. In normal mice AES markedly depressed exudation of eosinophils in the peritoneal cavity after repeated saline stimulation. Some of the immunological and clinical implications of a monospecific AES are discussed.

A soluble material has been isolated from schistosome eggs which in minute quantities without the addition of adjuvant induces sensitization to a delayed hypersensitivity type of granuloma forming around intact schistosome eggs. This material is secreted by intact eggs and is found in high concentration in the fluid released during the hatching process. When adsorbed to bentonite particles this substance elicits hypersensitivity type granuloma formation in specifically sensitized animals. The granuloma sensitizing factor also both induces and elicits delayed footpad swelling in mice. Quantities which sensitize with respect to these delayed type reactions do not induce antibody formation detectable by a sensitive hemagglutination. technique within the duration of the above experiments.