Abstract
Immunoglobulins were fractionated from two batches of horse anti-dog thymocyte plasma (ALS). These antiplasmas were made by different immunization schedules, and a considerable disparity was presented in their in vitro activities for cytotoxicity, leukoagglutination, and hemagglutination. One antiplasma showed high titers (high titer-ALS) in these tests while the other showed low titers (low titer-ALS).
Salting out with ammonium sulfate was adopted as a first step for the purification of antibodies. The crude gamma globulin (C.G.G.) obtained by salting out was further fractionated by G-200 Sephadex gel filtration and by DEAE-cellulose column chromatography. The highly purified immunoglobulin G (IgG) was obtained from the 7 S component fractionated by gel filtration. DEAE-cellulose batch production was also used for the isolation of IgG for mass production. The adequate ratio of mixing the wet DEAE-cellulose and C.G.G. solution (1.0g/100ml protein concentration) was 1 to 1.
The cytotoxicity of the low titer-ALS was mainly located in the 7 S component, while that of the high titer-ALS resided in both the 7 S and 19 S fractions. The hemagglutinin activity was mainly in the 19 S fraction in both the high titer and low titer-ALS.
