[Methods of protein gradient determination for diagnostic use in the clinical laboratory].

Computed quotients of the concentrations of individual proteins in serum and in cerebrospinal fluid recorded in a semilogarithmic way against the hydrodynamic radius of the molecules may be connected and so give lineals, the positions of which are believed to estimate the actual function of the blood-brain-barrier (Felgenhauer et al. 1974; 1976). It is demonstrated by examinations of different samples of blood and cerebrospinal fluid, that both the described method and the simple measurement of total protein in cerebrospinal fluid are of the same power in their application to estimate the function of the blood-brain-barrier. However, the method introduced by Felgenhauer et al. enables to demonstrate immunoglobulins not having reached the cerebrospinal fluid by entering from the blood stream and so giving rise to diagnose a local humoral immune response within the central nervous system. In this way the method of Felgenhauer et al. gives advantages to the diagnostics of neurological diseases.