This report is devoted to methodologies used in analyzing the C3b/C4b receptor (CR1, CD35) on erythrocytes (E), its soluble form, the CR1 structural or allotype polymorphism, and CR1 density polymorphism. In primates E CR1 serves as the main system for processing and clearance of complement opsonized immune complexes (IC). CR1 copy numbers decrease with aging of E in normal individuals. Erythrocyte CR1 is also decreased in pathological conditions such as systemic lupus erythematosus (SLE), HIV infection, certain hemolytic anemias, and many other conditions featuring immune complexes. Consequently, CRI on E has an important physiological role in immune complex handling and has interesting alterations in disease. (C) 1999 Elsevier Science Ltd.
- Complement 3b
- Laboratory techniques and procedures