Differential binding of IgA proteins of different subclasses and allotypes to Staphylococcal protein A

The binding of myeloma proteins of known subclass and allotype to staphylococcal protein A has been studied using affinity chromatography with Protein A-Sepharose CL-4B. Three IgA1 proteins did not show any binding, whereas two IgA2 A2m(1) and one IgA2 A2m(2) proteins were found to bind to the column.