SEROTONIN ANTIBODIES IN RELATION TO IMMUNE ACTIVATION IN MAJOR DEPRESSION

Serum antibodies against serotonin and gangliosides, the serum concent ration of serotonin in addition to indicators of immune activation, su ch as acute phase proteins (apps) and interleukin-6 (IL-6), were inves tigated in 20 major depressed patients and 32 normal controls. Antibod y-positive sera against serotonin and gangliosides were increased in p atients with major depression in comparison to normal controls. Serum concentrations of serotonin were significantly lower in depressed pati ents. These changes were accompanied by acute phase response character ized by elevated concentration of apps and IL-6. Compared with patient s showing positive response to antidepressant treatment, patients with treatment-resistant depression (TRD) had antibodies against serotonin and gangliosides that were twice as high, as well as a significantly higher IL-6 concentration. The results suggest that alterations in the serotoninergic system may be related to immune activation in major de pression and especially in treatment-resistant depression. (C) 1997 Jo hn Wiley & Sons, Ltd.