[Incomplete antigens derived from milk proteins in the serum of infants allergic to milk]

1. Sera of 22 children with cow's milk clinical hypersensitivity were studied to demonstrate the presence of substances immunologically related with milk. They were compared with 23 controls. The infants of both groups were feed with bovine milk. The immunogenic capacity of cow's milk and their major proteins were experimentally investigated. 2. Specific rabbit antisera were obtained by injection of antigens with incomplete Freund adjuvant. Double difussion gel, passive hemagglutination and ultramicromethod for the determination of antigen antibody precipitated were performed. 3. Immunogenicity was proved by precipitation and hemagglutination methods. by precipitation cow's milk antigens were present in 5 of 22 sera of antigenic patients, in 3 of them ALA antigens were present and in only 1 of them, caseina were present. By hemagglutination, 12 of 22 allergic infants showed ALA and BLG and 11 caseine (C). In 2 of 7 controls, beta lactoglobuline (BLG) was present and in an other one C. It was possible to detect incomplete antigens related with ALA, BLG, and C in allergic infants as well as controls. A significative difference was found for BLG (P less than 0.01) and it was highest (P less than 0.003) in infants with protein calorie malnutrition. 4. It is concluded that sensitization depends not only on stimulation of incomplete or complete antigens, as were observed in this study but on the host's capacity to form citrotropic antibody in humoral hypersensitivity or to stimulate lymphocytes in cellular immunity field.