LOWER PLASMA CC16, A NATURAL ANTIINFLAMMATORY PROTEIN, AND INCREASED PLASMA INTERLEUKIN-1 RECEPTOR ANTAGONIST IN SCHIZOPHRENIA - EFFECTS OFANTIPSYCHOTIC-DRUGS

Recently, it was suggested that in vivo activation of the monocytic an d T-lymphocytic arms of cell-mediated immunity (CMI) may occur in schi zophrenia and that antipsychotic drugs may modify CMI. The aim of the present study was to examine plasma soluble interleukin-2 receptor (sI L-2R), soluble suppressor/cytotoxic antigen (sCD8), interleukin-l rece ptor antagonist (IL-IRA), and Clara cell protein (CC16) concentrations in normal controls, nonmedicated schizophrenic patients, and schizoph renic patients treated with risperidone or loxapine. Plasma concentrat ions of IL-1RA were significantly higher in nonmedicated schizophrenic patients than in normal controls. Plasma CC16 was significantly lower in nonmedicated and loxapine-treated schizophrenic patients than in n ormal controls, whereas risperidone-treated patients had plasma CC16 l evels which were not significantly different from normal controls. Pla sma CC16 levels were significantly and positively related to age at on set of schizophrenia. Plasma sIL-2R was significantly higher in schizo phrenic patients who were treated with risperidone than in normal cont rols and nonmedicated schizophrenic patients. The results show that (i ) schizophrenia is accompanied by an activation of the monocytic arm o f CMI (i.e., increased plasma IL-1RA) and lower plasma levels of a nat ural anti-inflammatory and immunosuppressive agent, i.e. CC16, and tha t the latter may constitute a trait marker of schizophrenia; and that (ii) chronic treatment with atypical antipsychotic agents, i.e., rispe ridone, may normalize lower plasma CC16 and increase plasma sIL-2R.