Partial Characterization of Human Neutrophil Plasma Membrane Components which Bind Concanavalin A and Wheat Germ Agglutinin
Partial characterization of normal human polymorphonuclear neutrophil (PMN) plasma membrane components which bind Concanavalin A (Con A) and wheat germ agglutinin (WGA) was accomplished. Plasma membrane preparations of PMNs, separated on 9% SDS-polyacrylamide (PAGE) gels, showed the presence of 24 protein bands after Coomassie blue staining. Lactoperoxidase-catalyzed cell surface radioiodination showed that 16 of these bands represented cell surface proteins containing tyrosine residues. Molecular weights (MW) of these proteins ranged from 32,000-300,000 daltons. The PMNs were also labeled with 3H-WGA and 3H-Con A in separate experiments. Electrophoretic separation of plasma membrane components and subsequent fluorography revealed three radioactive bands in 3H-WGA labeled gels (MWs of 90,000 55,000, and 40,000) and two in 3H-Con A labeled gels (MWs of 70,000 and 34,000). The WGA/Con A labeling ratio was approximately 2:1. These labeled bands represented surface glycoprotein WGA and Con A receptors of PMN plasma membranes. Spectrophotometric comparison of 3H-WGA and 3H-Con A labeled bands indicated separate and distinct labeling of surface glycoproteins by WGA and Con A. These substantially different binding patterns indicate major differences in membrane carbohydrate residues that are sterically available for WGA and Con A binding.
Author Institution: Department of Zoological & Biomedical Sciences and College of Osteopathic Medicine, Ohio University
The Ohio Journal of Science. v86, n3 (June, 1986), 85-89