Effective avidin coating of erythrocytes by disulfide bond formation. Production of a stable rosetting agent for multiple applications.

A method is described for covalently coupling avidin to the membrane of glutaraldehyde-treated erythrocytes. The method is based on the use of the heterobifunctional coupling reagent N-succinimidyl-3-(2-pyridyldithio)propionate (SPDP) and appears to be more effective than other protein coupling techniques. The resulting avidin-coated red cells are very stable and can be stored for more than 1 year without aggregation or loss of biotin-binding activity. They can be used in various rosetting assays and were tested for T cell depletion or negative cell selection with five biotinylated monoclonal antibodies.