Complement factors and acute phase reactants in the Guillain-Barré syndrome

Elevated haptoglobin level of cerebrospinal fluid in Guillain-Barré syndrome revealed by proteomics analysis

Guillain-Barré Syndrome (GBS) is a rare autoimmune inflammatory polyneuropathy with a high risk of respiratory failure and unclear pathogenesis. Currently, there are no valid biomarkers for diagnosis of GBS. We used 2-DE and MS to analyze the protein profiles of five pairs of cerebrospinal fluid (CSF) samples of the GBS patients and the patient controls. Three proteins (orosomucoid, haptoglobin and apolipoprotein A-IV) were up-regulated, and two proteins (prostaglandin D2 synthase and transthyretin) were down-regulated in the CSF of the GBS patients. The CSF haptoglobin level, quantified by enzyme-linked immunosorbent assay, was significantly higher in the GBS patients (12.44 ± 2.70 μg/mL) compared to the chronic inflammatory demyelinating polyradiculoneuropathy (2.82 ± 0.83 μg/mL), viral meningitis (3.57 ± 0.97 μg/mL) and control patients (1.44 ± 0.35 μg/mL, p<0.05). This study indicated that protein profile analysis using a combination of 2-DE and MS provides an effective strategy for elucidating the pathogenesis and identifying potential CSF biomarkers for GBS. The raised intrathecal synthesis of haptoglobin specifically only in GBS patients, but not in patients with other neurological diseases examined, provides evidence of central nervous system involvement in GBS, and may be used as a potential diagnostic marker for GBS.

Serum and CSF humoral immunity in Guillain-Barré syndrome: clinical correlations

Paired samples of CSF and serum obtained from 29 patients affected with Guillain-Barré syndrome (GBS) were analyzed for various protein levels, including immunoglobulins and complement components. An attempt was made to correlate these findings to the clinical stage, severity, and duration of the disease. Intrathecal IgG synthesis was detected and quantified by means of a previously reported formula. It is practically constant in the GBS during the stage of stabilized paralysis, and is significantly greater in this stage than in the stage of progressive paralysis. Moreover, it increases with severity and duration (longer than 3 months) of the disease. Evidence of intrathecal C3 consumption is also presented.

Comparison of concentration of orosomucoid in serum and cerebrospinal fluid in different neurological diseases

We compared orosomucoid levels in cerebrospinal fluid (CSF) in patients with aseptic meningitis, multiple sclerosis, ischemic and hemorrhagic stroke, CNS-affecting leukemia/lymphoma, and CNS-tumor with the levels in a reference group not having neurologic diseases. Because of possible blood brain barrier damage, we corrected for orosomucoid derived from serum by using the orosomucoid index, i.e. (CSF/serum orosomucoid)/(CSF/serum albumin). Elevated CSF orosomucoid was found in several diseases. In no case, however, was there any evidence of intrathecal synthesis of the protein. We concluded that CSF orosomucoid determination, when used as the only, measure, is of limited clinical value.

Demyelination in vivo by Guillain-Barré syndrome and other human serum

Serum from patients with acute inflammatory polyneuropathy (the Guillain-Barré syndrome, GBS) demyelinates peripheral nerves in vivo more intensely than control human serum. To clarify the processes leading to demyelination we injected rat sciatic nerves with serum from GBS and control subjects in the presence of complement and examined the sequential morphologic changes over 7 days. One day after injection, five of six GBS sera but none of seven control sera caused vesicular demyelination; 3-5 days after injection both GBS and control sera produced macrophage-mediated demyelination. These observations suggest that GBS serum can initiate acute myelin injury through a humoral mechanism that is disease associated. This response appears to be distinct from delayed cell-mediated serum-induced demyelination that is not disease specific.

Abnormal serum factors in Guillain-Barré syndrome

The Guillain-Barré Syndrome (GBS) is generally considered to be a cell-mediated immunopathologic disease of the peripheral nervous system (PNS), although the evidence for this is indirect. Both in vitro and in vivo studies of sera from experimental animals with autoimmune demyelinating neuropathies suggest that serum factors, including antibodies to PNS myelin and/or Schwann cells, may be important in the pathogenesis of some of these disorders. More recently, similar in vitro and in vivo techniques, including the production of demyelination following intraneural injection in the rat have been employed to study sera from patients with GBS. The results of these studies demonstrate the presence of factor(s), as yet not fully characterized, that may be important in mediating demyelination. Moreover, in some patients with chronic or relapsing demyelinative inflammatory neuropathies and monoclonal gammopathy, there is evidence of antimyelin antibodies to PNS myelin. Further studies of serum from patients with acute GBS and these other neuropathies may clarify the role of serum factors in acquired inflammatory diseases of the PNS.