Biological Reaction to a Dye Protein I Congo red-azo-serum protein and its serological specificities

The hydrophilic dye-proteins have been prepared combining oxen serum protein with Congo red (CR) in varied proportion. DPO No.1 (50 mg. of CR per 100 cc. of serum), 2 (100 mg. per 100 cc), 3 (500 mg per 100 cc), 4 (1500 mg. per 100 cc). The binding between protein and dye molecules proved to be fairly strong by the test using several protein-precipitating agents and electrochromatograph. 1) The paraenteral introduction of these dye-proteins proved to produce two sorts of antibodies, the antibodies to the normal serum protein and to the dye-protein. The antibody to the normal serum decreased as the quantity of dye bound to antigen increased, showing the increased production of the antibody specific to the dye-protein. 2) Antibody formation varied according to the varied root of the introduction of antigen. Subcutaneous and intraperitoneal injection resulted in the higher antigen production comparing to the intravenous injection. The dye-protein introduced were mainly found in the macrophages. 3) The sensitized animals showed a severe shock symptomes by the reinjection of antigen. From the results mentioned above it has been suggested that the responsibility for the antibody formation to the dye-protein will be attributed to the macrophages, in which cytoplasm the injected antigen is found in a mass.