Work has been proposed to isolate and characterize the enzyme CNP from central nervous system tissue. In addition, antisera will be prepared to the purified enzyme to aid in the localization of the enzyme in central nervous system. In addition, the relationships among the various high molecular weight CNP proteins are being investigated. Cerebrospinal fluid of patients with demyelinating disorders is being examined for enzymatic activity. Immunological cross-reactivity of the various CNP antigens is also being determined.