IMMUNOCHEMICAL STUDIES ON THE BRAIN SPECIFIC PROTEIN

Abstract— In the soluble brain proteins of various species-man, ox, cat, rabbit, rat, mouse, hen, snake, frog and fish–there is a protein group which migrates more slowly than Moore's S-100 protein and faster than the albumin fraction on disc electrophoresis. The protein group is absent from any organs other than brain, and has a different pattern and number of fractions in different species. Immunochemically, the protein fraction group of the mammalian brains shows some common and identical distinctive antigenic determinants compared with the brain protein of the other animals-hen, snake, frog and fish. The protein group was designated the 'SPR' proteins, which were separated to 'P_II,', 'P_III', 'P_IV' and 'P_v' fractions. Common antigenic determinants are found in these fractions. The protein group is found in human brain in larger amounts in grey matter than in white matter and in small amounts in the cellular nuclei of human and bovine brain.