A SIMPLE TECHNIC FOR THE DEMONSTRATION OF A PHAGOCYTIC MONONUCLEAR CELL IN PERIPHERAL BLOOD: FIRST REPORT OF STUDIES ON THE MONONUCLEAR CELLS OF THE BLOOD

The purpose of this report is to describe a method by which a mononuclear cell constantly present in normal blood may be shown to be phagocytic, and to point out certain characters of the cell that suggest its origin. The origin, morphology and many of the functional activities of the polymorphonuclear leukocytes (neutrophilic, eosinophilic and basophilic) of the blood are known, but considerable uncertainty exists in regard to the mononuclear group of leukocytes. While it seems quite certain that lymphoblastic cells constitute a large part of the mononuclear leukocytes, the classification of the remaining mononuclear cells that are present is not satisfactory. An important aid in tracing the origin of cells in sections of tissue is their relationship to the surrounding ones that divide to form them, but the leukocytes in the blood stream do not arise there by mitosis, and once they are swept away in the blood their