Molecular Weight Differences in Chicken Isoantibodies.

SummaryEighteen chicken blood typing antisera were fractionated into different molecular weight classes by passing through a column of Sephadex G-200 gel. These antisera, prepared by isoimmunization, were specific for antigens of 5 blood group systems. Antibody activity in sera specific for two systems (D and L) was present in the high but not the low molecular weight fraction. With A, B and C sera, antibody activity was usually present in both fractions although B antibodies were primarily of low molecular weight. The property of the agglutinated erythrocytes to stick to glass was associated with the low molecular weight chicken antibodies. Differences in the time required for strong agglutination were also associated with molecular weight. With the macroglobulins the incubation period required for agglutination was about 4 times longer than with low molecular weight antibodies.