A longitudinal study of autoantibodies against central nervous system tissue and gangliosides in connective tissue diseases.

Our objective was to investigate longitudinally, antibodies against central nervous tissue (anti-CNS) derived from bovine brain and gangliosides GM 1, GD1a, GD1b, and GT1b in 91 patients with connective tissue diseases (systemic lupus erythematosus, n = 38; mixed connective tissue disease, n = 16; primary Sjogren's syndrome, n = 7; progressive systemic sclerosis, n= 13; polymyositis/dermatomyositis, n=4; overlap syndrome, n = 5; undifferentiated connective tissue disease, n = 8). Anti-CNS and anti-ganglioside antibodies, measured by enzyme-linked immunosorbent assay, were found in 73% and 63% of patients, respectively. Anti-CNS positive sera were also reactive in Western blotting in 74% of cases and recognized up to 14 different polypeptides from 29 to 130 kDa. Anti-CNS and anti-ganglioside antibodies reflected only in a limited extent the disease activity. In 27 of 58 patients, anti-CNS antibodies remained positive independently of disease activity and antibody levels did not correlate with the phases of exacerbations. A total of 36 of 60 anti-CNS-positive patients, in contrast to two of 22 anti-CNS-negative patients, had major neuropsychiatric manifestations (P < 0.001). Anti-ganglioside antibodies were not significantly associated with neuropsychiatric manifestations. In conclusion, our longitudinal data suggest that anti-CNS antibodies may be an important marker for the diagnosis of cerebral involvement in connective tissue diseases, but the pathogenic role of these autoantibodies remains to be determined.