Characterization of Antibody that Binds In Vivo to Normal Human Red Blood Cells
It has been well-documented that a subpopulation of normal circulating human red cells have antibody on their surfaces, and this antibody has been proposed to serve as a major mechanism for removal of senescent red cells from the circulation at the end of their lifespan (1). Antibodies of two different specificities have been reported to be enriched in high density human red cells. One is an antibody that appears to recognize an altered form of the Band 3 membrane protein (2). The other recognizes an a -galactosyl carbohydrate structure, found in small quantities in membrane glycolipids of Old World primates (3). As a basis for further understanding of the physiologic relevance of these antibodies, we have performed quantitative measurements of their contribution to in situ bound antibody on high density populations of normal human red cells. In addition, we have determined the number of binding sites of each type of antibody on different density populations that had been stripped of in situ antibody. To provide insight about the possible activity of the IgG dense cells, the IgG subclass distribution of the in situ antibody was also determined.
KeywordsWorld Primate Density Gradient Separation Dense Cell Population Fluorescence Histogram Membrane Glycolipid
Unable to display preview. Download preview PDF.
- 3.U. Galilli, The natural anti-Gal antibody, the B-like antigen, and human red cell aging, Blood Cells 14:205 (1988).Google Scholar
- 15.M. R. Clark, L. Corash and R. H. Jensen, Density distribution of aging, transfused human red cells, Blood 74 (Suppl. 1):217a (1989).Google Scholar