Objective: To investigate the clinical significance of specific/non-specific neuro-reactive autoantibodies in the pathogenesis of neuropsychiatric systemic lupus erythematosus (NPSLE).
Methods: Samples of serum and cerebrospinal fluid (CSF) were collected from 25 NPSLE patients, 11 patients with SLE complicated with central nervous system (CNS) infection (control group 1), and 10 SLE patients without CNS infection (non-NPSLE, control group 2)) were detected, Indirect immunofluorescence technique was used to detect the anti-nuclear antibody (ANA) based on the slides with human epithelium cell of laryngocarcinoma of the line Hep-2 or on the slides with cerebellum and peripheral nerve of monkey, he type of immunofluorescence were assayed.
Results: The percentages of ANA positive serum of the NPSLE, SLE control 1, and SLE control 2 groups were 92% (23/25), 100% (11/11), and 100% (10/10) respectively without significant differences between any 2 groups (all P > 0.05). The percentage of ANA positive CSF of the NPSLE was 60% (15/25), significantly higher than that of the SLE control group 1 (27%, 3/11, P < 0.01). There was no significant correlation between the titer of serum ANA and the titer of CSF ANA (P > 0.05). The positive rate of neuro-reactive autoantibodies was 40% (10/25), significantly higher than those of the 2 control groups (both 0, both P > 0.001).
Conclusion: (1) The ANA positivity in the CSF of the NPSLE group is associated with the disease activity and CNS involvement, the higher the titer of autoantibodies the severe the clinical manifestations. (2) The neuro-reactive autoantibodies in the serum may associate with NPSLE with still unknown mechanism.