Individual cerebrospinal fluid (CSF) proteins in the evaluation of increased CSF total protein

Summary The concentrations of 16 different proteins have been determined in unconcentrated CSF and in serum by radial immunodiffusion. The study included 20 patients with different neurological disorders and with total protein concentrations in CSF ranging between 26 and 299 mg per 100 ml. A simultaneous increase of most of the CSF proteins quantitated was found with increased total protein concentrations. A positive, statistically significant correlation between the concentrations of haptoglobin, ₂-macroglobulin and -lipoprotein in CSF, and the total protein concentration in CSF, however, was first obtained when the concentration of the protein in serum was also taken into account.The concentration of individual proteins in CSF seems to be influenced by the molecular weight of the proteins, and patients with normal, as well as increased, total protein concentrations in CSF seem to have a mechanism favouring the entrance into the CSF of proteins with low molecular weights.The following exceptions from these general rules became obvious: 1. The concentrations of prealbumin and transferrin in most CSF specimens, and the concentration of immunoglobulin G in some of the multiple sclerosis CSF specimens were higher than would be expected on the basis of the molecular weights and the concentrations in serum; 2. the concentration of gamma-trace protein in CSF was also considerably higher than would be expected on the basis of the molecular weight and the concentration in serum; in addition, no correlation existed between the concentration of this protein in CSF and the total protein concentration in CSF; 3. a positive correlation was shown to exist between the concentration of beta-trace protein in CSF and the total protein concentration in CSF, whereas the concentration in serum was unmeasurable, indicating a source other than serum for the increasing concentrations of this protein in CSF.Read in part before the Second International Meeting of the International Society for Neurochemistry, Milan, 3rd September, 1969 (Link, H., and O. Zettervall: Increased cerebrospinal fluid (CSF) total protein, a sign of blood-CSF-barrier damage. Report, Second International Meeting of the International Society for Neurochemistry, edited by Paoletti, R., pp. 269–270. Milan: Tamburini Editore 1969).