STUDIES ON PHAGOCYTOSIS.

Studies on the Mechanism of Phagocytosis

Phagocytic leukocytes have on their plasma membranes receptors for the Fc portion of immunoglobulin G (IgG) (1-9) and for a cleavage product of the third component of complement (C3) (3-5, 8, 10-15). Particles coated with IgG or C3 attach to the corresponding receptors on the plasma membranes of phagocytic cells. We have been studying the roles of these ligands (IgG and C3) and of their recepto...

Quantitative Studies of Phagocytosis

Kinetic analysis of the initial ingestion rate of albumin-coated paraffin oil particles by human granulocytes and rabbit alveolar macrophages was undertaken to study the mechanism of action of cations and of heat-labile opsonin on engulfment. The rate of uptake of the particles was stimulated by Ca(++), Mg(++), Mn(++), or Co(++). At high concentrations (> 20 mM) Ca(++) and Mg(++) inhibited the ...

Motion Picture Studies on Degranulation of Horse Eosinophils during Phagocytosis

Horse eosinophil function has been studied in vitro by means of phase contrast cinemicrophotography. Locomotion of horse eosinophils was inhibited by serum factors reacting with glass surfaces. Under appropriate conditions which eliminated this inhibitory effect, eosinophils moved about and ingested some particles as rapidly as did neutrophils. Eosinophils were attracted to and readily engulfed...

Studies on phagocytosis in patients with acute bacterial infections.

Polymorphonuclear leukocytes (PMN) and monocytes from 20 patients with acute bacterial infections were examined for phagocytic function. PMN of patients expressed markedly enhanced phagocytosis as measured by the ingestion of erythrocyte (E)IgG and IgG/C3b-coated E. Phagocytosis of E coated with C3b alone was not seen, while low levels of ingestion of iC3b-E by patients' PMNs was noted. Monocyt...

Studies on the role of phospholipids in phagocytosis.