Serum IgG anti-GD1a antibody and mEGOS predict outcome in Guillain-Barré syndrome.

OBJECTIVE: Approximately 15%-20% of patients with Guillain-Barré syndrome (GBS) are unable to walk independently at 6 months from the onset of neurological symptom. The modified Erasmus GBS outcome score (mEGOS) has been reported as a prognostic tool.Herein we investigated the association between a poor outcome, inability to walk independently at 6 months and presence of antiganglioside antibodies. METHODS: The clinical and serological data of 177 patients with GBS were retrospectively collected in Japan to assess the associations between a poor outcome and serum IgG antibodies against each ganglioside (GM1, GD1a, GalNAc-GD1a, GQ1b and GT1a). In addition, we investigated whether the combination of mEGOS and serum IgG antibodies against gangliosides is useful in predicting a poor outcome. RESULTS: The patients with IgG anti-GD1a antibodies more frequently showed poor outcomes than those without these antibodies (9 (36%) of 25 vs 8 (6%) of 127 patients, p<0.001). Particularly, 80% showed a poor outcome when they had both serum IgG anti-GD1a antibody and a high mEGOS of ≥10 on day 7 of admission. CONCLUSIONS: The combination of serum IgG anti-GD1a antibodies and a high mEGOS could help in making a more accurate prognosis of patients than mEGOS alone, especially for predicting poor outcomes.

Safety and efficacy of eculizumab in Guillain-Barré syndrome: a multicentre, double-blind, randomised phase 2 trial.

BACKGROUND: Despite the introduction of plasmapheresis and immunoglobulin therapy, many patients with Guillain-Barré syndrome still have an incomplete recovery. Evidence from pathogenesis studies suggests the involvement of complement-mediated peripheral nerve damage. We aimed to investigate the safety and efficacy of eculizumab, a humanised monoclonal antibody against the complement protein C5, in patients with severe Guillain-Barré syndrome. METHODS: This study was a 24 week, multicentre, double-blind, placebo-controlled, randomised phase 2 trial done at 13 hospitals in Japan. Eligible patients with Guillain-Barré syndrome were aged 18 years or older and could not walk independently (Guillain-Barré syndrome functional grade 3-5). Patients were randomly assigned (2:1) to receive 4 weeks of intravenous immunoglobulin plus either eculizumab (900 mg) or placebo; randomisation was done via a computer-generated process and web response system with minimisation for functional grade and age. The study had a parallel non-comparative single-arm outcome measure. The primary outcomes were efficacy (the proportion of patients with restored ability to walk independently [functional grade ≤2] at week 4) in the eculizumab group and safety in the full analysis set. For the efficacy endpoint, we predefined a response rate threshold of the lower 90% CI boundary exceeding 50%. This trial is registered with ClinicalTrials.gov, number, NCT02493725. FINDINGS: Between Aug 10, 2015, and April 21, 2016, 34 patients were assigned to receive either eculizumab (n=23) or placebo (n=11). At week 4, the proportion of the patients able to walk independently (functional grade ≤2) was 61% (90% CI 42-78; n=14) in the eculizumab group, and 45% (20-73; n=5) in the placebo group. Adverse events occurred in all 34 patients. Three patients had serious adverse events: two in the eculizumab group (anaphylaxis in one patient and intracranial haemorrhage and abscess in another patient) and one in the placebo group (depression). The possibility that anaphylaxis and intracranial abscess were related to eculizumab could not be excluded. No deaths or meningococcal infections occurred. INTERPRETATION: The primary outcome measure did not reach the predefined response rate. However, because this is a small study without statistical comparison with the placebo group, the efficacy and safety of eculizumab could be investigated in larger, randomised controlled trials. FUNDING: The Japan Agency for Medical Research and Development, Ministry of Health, Labor and Welfare, and Alexion Pharmaceuticals.

Expansions of intronic TTTCA and TTTTA repeats in benign adult familial myoclonic epilepsy.

Epilepsy is a common neurological disorder, and mutations in genes encoding ion channels or neurotransmitter receptors are frequent causes of monogenic forms of epilepsy. Here we show that abnormal expansions of TTTCA and TTTTA repeats in intron 4 of SAMD12 cause benign adult familial myoclonic epilepsy (BAFME). Single-molecule, real-time sequencing of BAC clones and nanopore sequencing of genomic DNA identified two repeat configurations in SAMD12. Intriguingly, in two families with a clinical diagnosis of BAFME in which no repeat expansions in SAMD12 were observed, we identified similar expansions of TTTCA and TTTTA repeats in introns of TNRC6A and RAPGEF2, indicating that expansions of the same repeat motifs are involved in the pathogenesis of BAFME regardless of the genes in which the expanded repeats are located. This discovery that expansions of noncoding repeats lead to neuronal dysfunction responsible for myoclonic tremor and epilepsy extends the understanding of diseases with such repeat expansion.

Paranodal dissection in chronic inflammatory demyelinating polyneuropathy with anti-neurofascin-155 and anti-contactin-1 antibodies.

OBJECTIVE: To investigate the morphological features of chronic inflammatory demyelinating polyneuropathy (CIDP) with autoantibodies directed against paranodal junctional molecules, particularly focusing on the fine structures of the paranodes. METHODS: We assessed sural nerve biopsy specimens obtained from 9 patients with CIDP with anti-neurofascin-155 antibodies and 1 patient with anti-contactin-1 antibodies. 13 patients with CIDP without these antibodies were also examined to compare pathological findings. RESULTS: Characteristic light and electron microscopy findings in transverse sections from patients with anti-neurofascin-155 and anti-contactin-1 antibodies indicated a slight reduction in myelinated fibre density, with scattered myelin ovoids, and the absence of macrophage-mediated demyelination or onion bulbs. Teased-fibre preparations revealed that segmental demyelination tended to be found in patients with relatively higher frequencies of axonal degeneration and was tandemly found at consecutive nodes of Ranvier in a single fibre. Assessment of longitudinal sections by electron microscopy revealed that detachment of terminal myelin loops from the axolemma was frequently found at the paranode in patients with anti-neurofascin-155 and anti-contactin-1 antibody-positive CIDP compared with patients with antibody-negative CIDP. Patients with anti-neurofascin-155 antibodies showed a positive correlation between the frequencies of axo-glial detachment at the paranode and axonal degeneration, as assessed by teased-fibre preparations (p<0.05). CONCLUSIONS: Paranodal dissection without classical macrophage-mediated demyelination is the characteristic feature of patients with CIDP with autoantibodies to paranodal axo-glial junctional molecules.

A Prospective, Multicenter, Randomized Phase II Study to Evaluate the Efficacy and Safety of Eculizumab in Patients with Guillain-Barré Syndrome (GBS): Protocol of Japanese Eculizumab Trial for GBS (JET-GBS).

BACKGROUND: Guillain-Barré syndrome (GBS) is an immune-mediated neuropathy that causes acute flaccid paralysis. Immunoglobulin and plasma exchange are established treatments for GBS; however, a substantial number of patients, particularly those with severe disease, have poor recovery and residual deficits. Recent studies suggest that complement activation plays a pivotal role in GBS-associated axonal degeneration, and eculizumab is a humanized monoclonal antibody that specifically binds to complement component 5 and potently inhibits complement activation. OBJECTIVE: This clinical trial aims to evaluate the efficacy and safety of eculizumab, a humanized monoclonal antibody directed against complement component 5, for treatment of GBS. METHODS: The Japanese Eculizumab Trial for GBS (JET-GBS) is a prospective, multicenter, placebo-controlled, double-blind, randomized phase II study conducted at 13 tertiary neurology centers and is funded by the Japan Agency for Medical Research and Development. A total of 33 GBS patients unable to walk independently within 2 weeks from symptom onset (Hughes functional grade 3-5) were randomized at a 2:1 ratio to receive either intravenous eculizumab (900 mg/day) or placebo once weekly for 4 weeks, followed by 20 weeks of follow-up. The primary endpoint for efficacy is the proportion of patients who regain their ability to walk without aid at 4 weeks after the first dose of the study treatment, while primary safety outcomes are the incidence of adverse events and serious adverse events during the trial. RESULTS: Enrollment for the trial began in August 2015. This trial is still ongoing. All participants have been enrolled, and follow-up will be completed in October 2016. CONCLUSIONS: This study is the first to investigate the efficacy and safety of eculizumab for GBS. In case of a positive result, we will plan a phase III trial to investigate this issue in a larger number of patients. CLINICALTRIAL: UMIN Clinical Trials Registry UMIN 000018171; https:/upload.umin.ac.jp/cgi-open-bin/ctr/ctr.cgi?function= brows&action=brows&type=summary&language=J&recptno=R000020978 (Archived by WebCite at http://www.webcitation.org/ 6lTiG8ltG). Clinical Trials.gov NCT02493725; https://clinicaltrials.gov/ct2/show/NCT02493725 (Archived by WebCite at http://www.webcitation.org/6lVJZXKSL).

Efficacy of intravenous methylprednisolone pulse therapy in patients with multiple sclerosis and neuromyelitis optica.

BACKGROUND: No large-scale studies have compared the efficacy of intravenous methylprednisolone pulse therapy (IVMP) for multiple sclerosis (MS) and neuromyelitis optica (NMO). OBJECTIVE: To explain differences in treatment responses of MS and NMO patients to IVMP. METHODS: Changes in neurological symptoms/signs and Expanded Disability Status Scale (EDSS) scores before and within 1 week of IVMP completion were obtained in 2010 at 28 institutions, and retrospectively collated from 271 MS (478 courses) and 73 NMO (118 courses) cases. RESULTS: In MS patients, decreased EDSS score was significant after the first (-0.8 ± 0.9), second (-0.7 ± 0.9), and third (-0.7 ± 0.8) courses (p < 0.05), but not after the fourth (-0.3 ± 0.7) and fifth (-0.5 ± 0.6). However, decreased EDSS score was only significant after the first course (-0.5 ± 1.5, p < 0.05) in NMO patients. EDSS score was significantly decreased in MS compared with NMO patients at the first course (p < 0.05), but not thereafter. Model analysis for EDSS score improvement at the first course, adjusting for covariates, showed significantly greater decreases in MS compared with NMO patients (p < 0.05). CONCLUSION: IVMP is effective in MS from the first to third courses, and in NMO at the first course. Additionally, IVMP is more efficacious in MS than NMO patients, even at the first course.

Clinical features of autoimmune autonomic ganglionopathy and the detection of subunit-specific autoantibodies to the ganglionic acetylcholine receptor in Japanese patients.

Autoimmune autonomic ganglionopathy (AAG) is a rare acquired channelopathy that is characterized by pandysautonomia, in which autoantibodies to ganglionic nicotinic acetylcholine receptors (gAChR) may play a central role. Radioimmunoprecipitation (RIP) assays have been used for the sensitive detection of autoantibodies to gAChR in the serum of patients with AAG. Here, we developed luciferase immunoprecipitation systems (LIPS) to diagnose AAG based on IgGs to both the α3 and ß4 gAChR subunits in patient serum. We reviewed the serological and clinical data of 50 Japanese patients who were diagnosed with AAG. With the LIPS testing, we detected anti-α3 and -ß4 gAChR antibodies in 48% (24/50) of the patients. A gradual mode of onset was more common in the seropositive group than in the seronegative group. Patients with AAG frequently have orthostatic hypotension and upper and lower gastrointestinal tract symptoms, with or without anti-gAChR. The occurrence of autonomic symptoms was not significantly different between the seropositive and seronegative group, with the exception of achalasia in three patients from the seropositive group. In addition, we found a significant overrepresentation of autoimmune diseases in the seropositive group and endocrinological abnormalities as an occasional complication of AAG. Our results demonstrated that the LIPS assay was a useful novel tool for detecting autoantibodies against gAChR in patients with AAG.

Successful treatment of infliximab-associated immune-mediated sensory polyradiculopathy with intravenous immunoglobulin.

Infliximab, a tumor necrosis factor-alpha antagonist, is used to treat many inflammatory diseases. Various forms of demyelinating neuropathies have been reported as neurological complications associated with infliximab use. There have been few reports of pure sensory neuropathy associated with infliximab. We report the clinical, electrophysiological, and pathological findings of a patient with subacute sensory polyradiculopathy 1 month after infliximab therapy for psoriasis vulgaris. Immune-mediated pathogenesis was suggested by positive anti-ganglioside antibodies and rapid response to intravenous immunoglobulin. This is the first reported case of sensory polyradiculopathy with positive anti-ganglioside antibodies following infliximab therapy. Our findings suggest the clinical importance of immunological investigations and treatment in demyelinating neuropathies following infliximab therapy.

Recurrent K3E mutation in Cu/Zn superoxide dismutase gene associated with amyotrophic lateral sclerosis.

Cu/Zn superoxide dismutase (SOD1) gene mutations are the most frequently reported genetic causes of amyotrophic lateral sclerosis (ALS). The objective of the study was to describe a clinical phenotype and haplotype background of Polish and Japanese ALS patients harbouring the K3E SOD1 mutation. The K3E mutation was identified by direct sequencing, high resolution melting analysis or high-throughput microarray-based resequencing system. Microsatellite polymorphic markers flanking SOD1 were genotyped in members of six kindreds and two SALS patients. Results demonstrated that the K3E mutation was responsible for classic ALS. The median age of onset was 54 years. The clinical phenotype did not substantially differ between SALS and FALS cases of either ethnic origin, with some intrafamiliar variabilities. There was a limb onset in 92% of patients. In patients with bulbar syndrome, dysphagia predominated over dysarthria. Respiratory insufficiency was found in 61.1% of patients (19-84 months after the first symptoms onset). Median survival was 101 months with age of death ranging from 45 to 77 years. K3E was the most frequent SOD1 mutation among Polish FALS patients. It originated independently, on different haplotype background in the Polish and Japanese populations. In conclusion, recurrent K3E mutation results in a relatively slowly progressing limb onset ALS with classic phenotype.

A new maneuver for repetitive nerve stimulation testing in the trapezius muscle.

INTRODUCTION: The repetitive nerve stimulation (RNS) test in the trapezius muscle is used widely for the evaluation of myasthenia gravis. However, pseudofacilitation is often difficult to avoid in this muscle and may compromise the detection of small decremental responses. We have devised a new maneuver to reduce pseudofacilitation. METHODS: Using our maneuver, the shoulder of a supine subject is elevated passively and is held firmly by the examiner. Four conventional maneuvers as well as ours were compared with regard to pseudofacilitation that was maximal at the second wave in 14 control subjects. RESULTS: Pseudofacilitation at the second and fourth waves was the smallest using our maneuver. Up to 15% pseudofacilitation was observed using the other maneuvers. CONCLUSION: Pseudofacilitation in the trapezius muscle is mainly due to shortening of the muscle belly. It can be reduced greatly by shortening the muscle in advance.

An antibody to the GM1/GalNAc-GD1a complex correlates with development of pure motor Guillain-Barré syndrome with reversible conduction failure.

Antibodies to a ganglioside complex consisting of GM1 and GalNAc-GD1a (GM1/GalNAc-GD1a) are found in sera from patients with Guillain-Barré syndrome (GBS). To elucidate the clinical significance of anti-GM1/GalNAc-GD1a antibodies in GBS, clinical features of 58 GBS patients with IgG anti-GM1/GalNAc-GD1a antibodies confirmed by enzyme-linked immunosorbent assay and thin layer chromatography immunostaining were analyzed. Compared to GBS patients without anti-GM1/GalNAc-GD1a antibodies, anti-GM1/GalNAc-GD1a-positive patients more frequently had a preceding respiratory infection (n=38, 66%, p<0.01) and were characterized by infrequency of cranial nerve deficits (n=9, 16%, p<0.01) and sensory disturbances (n=26, 45%, p<0.01). Of the 28 anti-GM1/GalNAc-GD1a-positive patients for whom electrophysiological data were available, 14 had conduction blocks (CBs) at intermediate segments of motor nerves, which were not followed by evident remyelination. Eight of 10 bedridden cases were able to walk independently within one month after the nadir. These results show that the presence of anti-GM1/GalNAc-GD1a antibodies correlated with pure motor GBS characterized by antecedent respiratory infection, fewer cranial nerve deficits, and CBs at intermediate sites of motor nerves. The CB may be generated through alteration of the regulatory function of sodium channels in the nodal axolemma.

[A case of Sjögren syndrome with subacute combined degeneration-like posterior column lesion on cervical MRI].

We report a case of a 67 year-old man with bilateral sensory ataxia of the upper extremities. He was diagnosed as having ANCA-related angitis and Sjögren syndrome at age 60. On admission to our hospital at age 67, he presented with severe sensory ataxia in his upper extremities, while his lower extremity neurological symptoms were limited to the absence of tendon reflexes. Cervical MRI showed an increased T2 signal intensity in an area limited to the bilateral cuneate fasciculus. Serum levels of vitamin B12 and folic acid were normal. Plasma homocysteine, serum and urine methylmalonic acid were also normal. Eight-week intramuscular administration of vitamin B12 did not improve either his disorder or the MRI findings. His sensory ataxia might be attributed to Sjögren syndrome-associated ganglionopathy at the cervical level, and the MRI findings might reflect centripetal Wallerian degeneration in the cuneate fasciculus. Gracilis fasciculus are well-known as vulnerable regions in Sjögren-associated myelopathy, whereas cervical myelopathy, limited to cuneate fascicules, can emerge as Sjögren-associated disorders.

Anti-GM1/GD1a complex antibodies in GBS sera specifically recognize the hybrid dimer GM1-GD1a.

It is now emerging the new concept that the antibodies from some patients with Guillain-Barré syndrome (GBS) recognize an antigenic epitope formed by two different gangliosides, a ganglioside complex (GSC). We prepared the dimeric GM1-GD1a hybrid ganglioside derivative that contains two structurally different oligosaccharide chains to mimic the GSC. We use this compound to analyze sera from GBS patients by high-performance thin-layer chromatography immunostaining and enzyme-linked immunosorbent assay. We also synthesized the dimeric GM1-GM1 and GD1a-GD1a compounds that were used in control experiments together with natural gangliosides. The hybrid dimeric GM1-GD1a was specifically recognized by human sera from GBS patients that developed anti-oligosaccharide antibodies specific for grouped complex oligosaccharides, confirming the information that GBS patients developed antibodies against a GSC. High-resolution (1)H-(13)C heteronuclear single-quantum coherence-nuclear overhauser effect spectroscopy nuclear magnetic resonance experiments showed an interaction between the IV Gal-H1 of GM1 and the IV Gal-H2 of GD1a suggesting that the two oligosaccharide chains of the dimeric ganglioside form a single epitope recognized by a single-antibody domain. The availability of a method capable to prepare several hybrid gangliosides, and the availability of simple analytical approaches, opens new perspectives for the understanding and the therapy of several neuropathies.

Antibodies against ganglioside complexes in Guillain-Barré syndrome and related disorders.

Guillain-Barré syndrome (GBS) is acute autoimmune neuropathy, often subsequent to an infection. Serum anti-ganglioside antibodies are frequently elevated in titer. Those antibodies are useful diagnostic markers and possible pathogenetic factors. Recent data demonstrated that sera from some patients with GBS react with ganglioside complexes (GSCs) consisting of two different gangliosides, but not with each constituent ganglioside. Those antibodies may specifically recognize a new conformational epitope formed by two gangliosides. In particular, the antibodies against GD1a/GD1b and/or GD1b/GT1b complexes are associated with severe GBS requiring artificial ventilation. The antibodies to GM1/GalNAc-GD1a and those to GSCs containing GQ1b or GT1a are associated with pure motor GBS and Fisher syndrome, respectively. In contrast, the binding activities of the antibodies highly specific to GD1b are strongly inhibited by the addition of GD1a to GD1b. Gangliosides along with other components as cholesterol are known to form lipid rafts, in which two different gangliosides may form a new conformational epitope. Future investigation is necessary to elucidate the roles of GSCs in the plasma membrane and of the clinical relevance of the anti-GSCs antibodies.

[Case of pure motor Guillain-Barré syndrome with motor conduction block and anti-GM1/GalNAc-GD1a antibody].

A 38-year-old man presented with distal-dominant limb weakness two weeks after an upper respiratory infection. He had no sensory and autonomic signs and no cranial nerve involvement during the course of the disease. Tendon reflexes were preserved except for an absent Achilles' tendon reflex. His disability at nadir was grade 2 on the Hughes functional scale. Cerebrospinal fluid analysis showed albuminocytologic dissociation and he was diagnosed with pure motor Guillain-Barré syndrome (GBS). Thin-layer chromatography immunostaining and an enzyme-linked immunosorbent assay revealed an immunoglobulin G antibody to the ganglioside complex GM1/GalNAc-GD1a in his acute phase serum. A serial nerve conduction study revealed conduction block in the median and ulnar nerve trunks and temporal dispersion in the tibial nerve, without an evident remyelination pattern during the course of the disease. A sensory nerve conduction study was normal. According to Hadden's criteria, the electrodiagnostic findings were judged as a primary demyelinating pattern. Weakness and abnormal motor nerve conduction recovered rapidly after intravenous immunoglobulin therapy. In view of the localization of GM1 and GalNAc-GD1a on the axolemma of the motor nerves, the clinical course and electrophysiological features may have resulted from functional conduction failure at the nodes of Ranvier of the motor nerves, rather than primary demyelination or axonal degeneration. The illness resembled acute motor conduction block neuropathy characterized by preserved sensory function, an early conduction block at intermediate nerve segments, and good recovery. GM1 and GalNAc-GD1a may form a complex in the axolemma at the nodes of Ranvier or paranodes of the motor nerves, and may be a target antigen in pure motor GBS; especially in the form with acute motor conduction block neuropathy. The present case is the first description of a GBS patient with an IgG anti-GM1/GalNAc-GD1a antibody.

Antibodies to ganglioside complexes consisting of asialo-GM1 and GQ1b or GT1a in Fisher and Guillain-Barré syndromes.

To determine the epitopes of ganglioside complexes (GSCs) containing GQ1b or GT1a, we investigated their reactivity to GSCs consisting of asialo-GM1 (GA1) and GQ1b or GT1a using IgG anti-GQ1b- or anti-GT1a-positive sera. Nine anti-GQ1b-positive sera had higher activity to GA1/GQ1b than to GQ1b, only five of which reacted with GM1/GQ1b and GD1b/GQ1b. Five of 14 sera positive for GA1/GT1a and GM1/GT1a were negative for GA1/GQ1b and GM1/GQ1b. Sialic acids attached to the internal galactose of gangliotetraose can influence the reactivity of anti-GSC antibodies. Screening for antibodies to GSCs containing GA1 is useful for elucidation of the antibody-mediated pathophysiology.

Antibodies against gangliosides and ganglioside complexes in Guillain-Barré syndrome: new aspects of research.

Guillain-Barré syndrome (GBS) is an acute autoimmune neuropathy, often preceded by an infection. Serum anti-ganglioside antibodies are frequently elevated in titer. Those antibodies are useful for diagnosis. Some of them also may be directly involved in the pathogenetic mechanisms by binding to the regions where the respective target ganglioside is specifically localized. We have recently found the presence of the antibody that specifically recognizes a new conformational epitope formed by two gangliosides (ganglioside complex) in the acute-phase sera of some GBS patients. In particular, the antibodies against GD1a/GD1b and/or GD1b/GT1b complexes are associated with severe GBS requiring artificial ventilation. Some patients with Miller Fisher syndrome also have antibodies against ganglioside complexes including GQ1b; such as GQ1b/GM1 and GQ1b/GD1a. Gangliosides along with other components as cholesterol are known to form lipid rafts, in which the carbohydrate portions of two different gangliosides may form a new conformational epitope. Within the rafts, gangliosides are considered to interact with important receptors or signal transducers. The antibodies against ganglioside complexes may therefore directly cause nerve conduction failure and severe disability in GBS. More study is needed to elucidate the roles of the antibodies against ganglioside complexes.

[Two cases of idiopathic carotid-cavernous fistula with headache and ophthalmoplegia].

We report two cases of idiopathic carotid-cavernous fistula (CCF) with primary symptoms of headache and diplopia. A 47-year-old woman presented with throbbing headache in her right frontal region followed by right trochlear nerve palsy. Brain magnetic resonance imaging (MRI) was normal but magnetic resonance angiography (MRA) and computed tomographic angiography (CTA) revealed abnormal signals around the right cavernous sinus. CCF was diagnosed by conventional angiography. The symptoms improved naturally but after about 1 year she suddenly exhibited conjunctival congestion. A 41-year-old man complained of fluctuating headache with sudden left abducens nerve palsy. MRI and MRA were normal but CTA showed abnormal signals around the left cavernous sinus. A final diagnosis of CCF was made by conventional angiography and he was transferred to another hospital for stereotactic radiosurgery. Diagnosis of CCF tends to be delayed in cases presenting with only headache and external ophthalmoplegia. However, CCF with cortical vein drainage can lead to cerebral hemorrhage and early correct diagnosis is needed. Our cases showed a dilated superior ophthalmic vein in enhanced CT and an abnormal signal around the cavernous sinus in CTA. Therefore, CTA may be useful as a relatively non-invasive method that can provide diagnostic clues for CCF.

Harmful effects of anti-GalNAc-GD1a antibodies and TNF-alpha on rat dorsal root ganglia.

The clinical characteristics of five (22%) of 23 patients with Guillain-Barré syndrome (GBS), whose serum contained immunoglobulin G (IgG) antibodies to the ganglioside N-acetylgalactosaminyl GD1a (GalNAc-GD1a), included pure motor weakness of the axonal type. These patients had a relatively good prognosis, but displayed higher serum tumor necrosis factor-alpha (TNF-alpha) titers than the other GBS patients. We examined the effect of serum from these patients with IgG anti-GalNAc-GD1a antibodies on neurites from cultured rat dorsal root ganglia (DRG) and found it to damage the myelin in well-elongated DRG neurites and monolayer cultures of Schwann cells and neurons. In the regeneration model, serum from these patients delayed neurite extension and inhibited Schwann cell proliferation. Neurons in cultured monolayers showed vacuolation and decreased rapidly in number. Schwann cells were also vacuolated and readily detached from the substratum. The effects of IgG anti-GalNAc-GD1a antibodies purified from one of the patients, rabbit serum after immunization with GalNAc-GD1a, and recombinant TNF-alpha were also examined. IgG anti-GalNAc-GD1a antibodies mainly inhibited the regeneration and preservation of neurons, while TNF-alpha mainly induced morphological changes in well-proliferated Schwann cells and myelin.