In Vitro Histamine Release from Blood Cellular Elements of Rabbits Infected with Schistosoma mansoni

Abstract

Histamine release was detectable both in the presence and absence of passive cutaneous anaphylactic antibodies. Ion exchange chromatography, used to separate some of the antibodies in the rabbit antisera, revealed that fractions containing most of the IgG immunoglobin had all the detectable flocculating activity. Electro-phoretically faster immunoglobulins contained passive cutaneous anaphylactic activity but not detectable flocculating titer. A pure platelet suspension from sensitized rabbits did not release histamine when challenged with antigen. Histamine release did occur in the presence of whole washed blood when similarly challenged. A significant increase in histamine release was noted when normal blood platelets in a suspension of washed sensitized cells were added to antigen.