EXPERIMENTAL EOSINOPHILIA WITH AN EXTRACT OF AN ANIMAL PARASITE

Abstract

The functions of the eosinophil cells remain one of the mysteries of biology.Our knowledge of these cells includes their morphology, their place of origin and the naming of the various clinical conditions in which their number either in circulating blood or locally in the tissues varies from the usual.Of the r\l=o^\le played by the eosinophil leukocytes in the economy of the body we know little.Experimental work has lagged far behind speculation in this field.Some months ago a phase of the problem of the functions of the eosinophil cells was suggested by two observations.In 1910 a case of bronchial asthma came to my notice showing extreme blood-changes\p=m-\a leukocytosis of 56,000, an eosinophilia of 77 per cent.1This was placed on record together with a review of the literature of this well-known feature of asthma.At about the same time Goldschmidt2 recorded the observation that laboratory workers whose duties led them to dissect Ascarides became sensitized so that tenderness and swelling of the fingers, conjunctivitis, coryza, sneezing, cough and asthmatic attacks resulted, and became increasingly severe with repeated handling of the material.It was found that the asthmatic attacks had a remarkable periodicity and in some instances persisted two weeks after cessation of contact with the worms.Several baffling problems are linked, however complexly, by these observations.Common to both bronchial asthma and Ascaris infestation is an increase of the eosinophils of the blood.One may well ask the significance of the eosinophilia in this association.Further, it has been suggested that asthma may be classified among the phenomena of anaphylaxis.3Many of the reflex and toxic symptoms seen clinically in