[Specificity and mechanism of action of the granulocyte chalon and its role in the regulatory system of granulopoiesis].

An inhibitor of granulopoiesis is described which, on the basis of its cellular origin and its specificity of action, can be identified as the granulocytic chalone. A control system is discussed which is based on the interplay of leukocytosis inducing factors, colony stimulating factors and the granulocytic chalone. The granulocytic chalone inhibits all immature myeloid cells of the bone marrow by interacting with specific receptor sites on the cell membrane.