Anti-alpha B-crystallin immunoreactivity in inflammatory nervous system diseases

alpha B-Crystallin, a small heat shock protein, is an immunodominant antigen with increased tissue expression in demyelination. To investigate the humoral response against alpha B-crystallin, the sera and CSF samples of patients with multiple sclerosis (MS), Guillain-Barré syndrome (GBS), neuro-Behçet's disease (NBD) and other non-inflammatory neurological diseases (NIND) were screened by enzyme-linked immunosorbent assay for anti-alpha B-crystallin IgG and IgM antibodies. Serum and CSF IgG antibody responses to alpha B-crystallin were significantly elevated only in NBD patients (serum IgG, NBD 1.29 +/- 0.49 vs. NIND 0.95 +/- 0.39, P = 0.01; CSF IgG, NBD 1.22 +/- 0.64 vs. NIND 0.81 +/- 0.35, P = 0.01). Similarly, high serum IgM antibody titres were also detected in NBD (1.83 +/- 0.72 vs. 1.16 +/- 0.49, P = 0.0005) and in MS (1.57 +/- 1.07, P = 0.046), whereas elevated CSF IgM responses were observed only in GBS (2.09 +/- 1.09 vs. 1.41 +/- 0.7, P = 0.007). Humoral responses against alpha B-crystallin are increased in NBD and GBS, which may implicate this central nervous system antigen in the causation and pathogenesis of these inflammatory nervous system disorders.