Elevated plasma levels of S-100b protein in schizophrenic patients.

BACKGROUND: In this study, we examined the possibility that structural damage to the brain may play a role in the pathogenesis of schizophrenia. METHODS: We compared plasma levels of S-100b protein in 20 patients with schizophrenic psychosis and 20 age- and gender-matched healthy blood donors. Concentrations of S-100 protein were determined by microtiter-based immunofluorometric assay detecting predominantly S-100b. RESULTS: Mean concentrations of S-100b protein in blood were significantly (p < or = .001) higher in schizophrenic patients (0.165 +/- 0.138 microgram/L) compared to control subjects (0.054 +/- 0.031 microgram/L). Levels did not correlate with age of onset or duration of psychosis. CONCLUSIONS: Our findings indicate that patients with schizophrenia may suffer ongoing structural damage to cells of the central nervous system, and that the concentration of S-100b protein in plasma may help to identify clinical subgroups in schizophrenia.