Serum antigens of cattle. VI. Isolation and properties of an intracellular antigen (Ecl) from cattle erythrocytes.

The erythrocyte antigen (Ecl) of cattle has been isolated using DEAE-cellulose chromatography, Sephadex gel filtration, and isoelectrofocusing. The purified antigen is free from hemoglobin and migrates as a single protein on polyacrylamide gels. It exhibits an absorption maximum at 278 nm and has a molecular weight of about 100 000; its isoelectric point is 4.95. The antigen has a carbohydrate moeity and loses its activity after oxidation with periodate. The evidence suggests that it is not a common isozyme, but is exact identity remains unknown.