Serum immunoglobulin levels, determined by radial immunodiffusion, were correlated with clinical course in a group of newly admitted acutely ill male schizophrenic patients, whether treated with chlorpromazine or drug-free. The lgG, lgA, and lgM levels were significantly elevated in this population of schizophrenic patients as compared with normal controls. Patients with levels of both lgG and lgA below the median were significantly more likely to show clinical improvement during course of hospitalization than those in whom either or both imminoglobulin levels were above the median.
Amkraut A, Solomon G, Allansmith M, Rappaport M. Immunoglobulins and Improvement in Acute Schizophrenic Reactions. Arch Gen Psychiatry. 1973;28(5):673–677. doi:10.1001/archpsyc.1973.01750350053010