Abstract
Bovine serum protein component, which is functionally identical with a mouse isoantigenic γ-Globulin (complement component) controlled by a single gene, was isolated by using Hc^0/Hc^0 mouse serum as a "Reagent". The purified preparation showed one β-migrating protein on immunoelectrophoresis using rabbit anti-bovine serum, and one antigen-antibody precipitate line against the same antiserum on the agar gel double diffusion test. But no cross reaction with the antiserum of Hc^0/Hc^0 mouse anti-Hc^1/Hc^1 mouse serum was recognized. The purified β-globulin was quite stable in its hemolytic activity even after being heated at 56℃ for 60 min., and it resisted a rather low pH. (4.2), for one month. The β-globulin allowed completion of the lysis of sensitized sheep erythrocytes in the presence of Hc^0/Hc^0 mouse serum, even when the reaction medium contained 0.01 M EDTA (Tetra-sodium Ethyle-nediaminete traacetate). The molecular size of the β-globulin appeared to be in the 7S category according to the elution pattern from Sephadex G-200 column. The purified β-globulin preparation had approximately 22-fold activity with respect to original bovine serum, and the rate of hemolytic reaction during the first 300 sec. was a liner function of the β-globulin concentration in the presence of Hc^0/Hc^0 mouse serum. On the basis basis of the characteristics of the β-globulin, the relationship between allergy or immunity and this protein was discussed.
