Histidine Decarboxylase Activity of Basophils from Chronic Myelogenous Leukemic Patients. Origin of Blood Histamine.

It is well established that relatively large amounts of histamine are present in tissue mast cells (1–3), and leukocytes (4–6), especially the granulocytes and probably largely the basophils (4,7).† Eosinophils have also been claimed to contain histamine (7). A polemic has existed since the first report of Code in 1936 (4) regarding the origin of histamine in the body. Some argued that it originated solely from ingestion with food and from decarboxylation of histidine by intestinal flora, and others asserted that it also originated by the action of a tissue decarboxylase. The bulk of evidence supports the concept that tissue mast cells of mammalian organisms decarboxylate histidine to histamine (1–3,11) although some workers have denied this (8). Only a few investigators have ruled out bacterial decarboxylation in their in vitro studies. These are Werle, et al. (12) who used sterile precautions and tested for contamination after incubation; Gustafsson, Kahlson and Rosengren who worked with germ-free rats (9); and Schindler, Day and Fisber who worked with sterile tissue cultures of malignant murine mast cells (11).