Immunological determination of galactosylceramide level in blood as a serum index of active demyelination.

An enzyme-linked immunosorbent assay (ELISA) to determine the level of galactosylceramide (GalC) in biological fluids is described. The assay uses GalC-coated plastic microtiter plates, with binding of an antibody to GalC detected by a peroxidase-labeled second antibody. The GalC level was directly estimated in the biological samples, without prior extraction, by competition with the coated hapten. This method allows the detection of 62 pmol of GalC (1.2 nmol/ml). Results using this procedure revealed positive sera only among patients suffering a myelin-destructive process: either primary, as in multiple sclerosis, or secondary to brain damage, as during ischemic strokes.