Nature of the Leucocytosis-inducing Factor in Plasma

Abstract

IT is now well known that fever¹ and leucocytosis², brought about by typhoid vaccine, are the result of the formation of at least two separate factors and not due to the direct action of vaccine (endotoxin) on the fever centre or on the bone marrow. Fukuda and Matsumoto³ have recently demonstrated that the two factors act quite independently of each other and that in adrenalectomized animals, in particular, in spite of the normal occurrence of fever response due to the formation of the endogenous fever factor, leucocytosis fails to occur, and the leucocytosis-inducing factor cannot be detected by the use of passive transfer technique. The formation of the leucocytosis-inducing factor was found to depend solely on the presence of glycocorticoids. Moreover, the formation of this factor after the injection of vaccine could be inhibited by insulin administration, and conversely enhanced in an alloxan-diabetic state⁴. It was the object of the present work to examine whether or not this leucocytosis-inducing factor which is detectable in the circulating blood is identical with the ‘leucocytosis-promoting factor’ of Menkin⁵ which was isolated from sterile exudates.