Anti-GM2 ganglioside antibodies are a biomarker for acute canine polyradiculoneuritis.

Acute canine polyradiculoneuritis (ACP) is considered to be the canine equivalent of the human peripheral nerve disorder Guillain-Barré syndrome (GBS); an aetiological relationship, however, remains to be demonstrated. In GBS, anti-glycolipid antibodies (Abs) are considered as important disease mediators. To address the possibility of common Ab biomarkers, the sera of 25 ACP dogs, 19 non-neurological, and 15 epileptic control dogs were screened for IgG Abs to 10 glycolipids and their 1 : 1 heteromeric complexes using combinatorial glycoarrays. Anti-GM2 ganglioside Abs were detected in 14/25 ACP dogs, and anti-GA1 Abs in one further dog. All controls except for one were negative for anti-glycolipid Abs. In this cohort of cases and controls, the glycoarray screen reached a diagnostic sensitivity of 60% and a specificity of 97%; a lower sensitivity (32%) was reported using a conventional glycolipid ELISA. To address the possible pathogenic role for anti-GM2 Abs in ACP, we identified GM2 in canine sciatic nerve by both mass spectrometry and thin layer chromatography overlay. In immunohistological studies, GM2 was localized predominantly to the abaxonal Schwann cell membrane. The presence of anti-GM2 Abs in ACP suggests that it may share a similar pathophysiology with GBS, for which it could thus be considered a naturally occurring animal model.

Long-term response to rituximab and fludarabine combination in IgM anti-myelin-associated glycoprotein neuropathy.

We report the clinical response and biological effects of treatment with rituximab and fludarabine (RF) in five patients with IgM anti-myelin-associated glycoprotein (MAG) demyelinating neuropathy. Between November 2006 and October 2009, four men and one woman aged 52-85 years received intravenous rituximab at 375 mg/m(2) on day 1 and oral fludarabine at 40 mg/m(2) /day from days 1 to 5, in a treatment cycle that was repeated every month for up to 6 months. Two patients had IgM monoclonal gammopathy of undetermined significance and three low tumor mass Waldenstrom's macroglobulinemia. Four patients showed a major hematological response with a decrease in anti-MAG titer in three and clearing in one. One patient did not respond. For the responding patients, symptoms and electrophysiological parameters improved significantly. No patient relapsed at post-RF treatment follow-up (12-45 months), and no toxicity was reported. The combination of RF induced significant responses in IgM anti-MAG demyelinating neuropathies, without toxicity. Clinical improvements were correlated to hematological and immunological results.

A bacterium lipopolysaccharide that elicits Guillain-Barré syndrome has a GM1 ganglioside-like structure.

There is a strong association between Guillain-Barré syndrome (GBS) and Penner's serotype 19 (PEN 19) of Campylobacter jejuni. Sera from patients with GBS after C. jejuni infection have autoantibodies to GM1 ganglioside in the acute phase of the illness. Our previous work has suggested that GBS results from an immune response to cross-reactive antigen between lipopolysaccharide (LPS) of the Gram-negative bacterium and membrane components of peripheral nerves. To clarify the pathogenesis of GBS, we have investigated whether GM1-oligosaccharide structure is present in the LPS of C. jejuni (PEN 19) that was isolated from a GBS patient. After extraction of the LPS, the LPS showing the binding activity of cholera toxin, that specifically recognizes the GM1-oligosaccharide was purified by a silica bead column chromatography. Gas-liquid chromatography-mass spectrometric analysis has shown that the purified LPS contained Gal, GalNAc, and NeuAc, which are sugar components of GM1 ganglioside. 1H NMR methods [Carr-Purcell-Meiboom-Gill (CPMG), total correlation spectroscopy (TOCSY), and nuclear Overhauser effect spectroscopy (NOESY)] have revealed that the oligosaccharide structure [Gal beta 1-3 GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta] protrude from the LPS core. This terminal structure [Gal beta 1-3GalNAc beta 1-4(NeuAc alpha 2-3)Gal beta] is identical to the terminal tetrasaccharide of the GM1 ganglioside. This is the first study to demonstrate the existence of molecular mimicry between nerve tissue and the infectious agent that elicits GBS.

Routine blood monitoring in maintenance immunoglobulin treatment of inflammatory neuropathy: Is it clinically relevant?

BACKGROUND: Pre-treatment screening for IgA deficiency and close monitoring of full blood count(FBC) and renal function is recommended with intravenous immunoglobulin(IVIg) therapy in neurological diseases. AIMS: To examine the frequency of biochemically defined and clinically significant episodes of treatment associated haemolysis, neutropenia, thrombocytopenia and acute kidney injury(AKI) in a cohort of patients on maintenance Immunoglobulin(Ig) therapy for inflammatory neuropathy. METHODS: A retrospective review of routine blood monitoring in patients from two UK specialist peripheral nerve centres. Accepted definitions for clinically and biochemically significant haemolysis, neutropenia, thrombocytopenia and AKI were used. RESULTS: 1919 infusion episodes in 90 patients were analysed. Age(mean(S.D)) = 58.09(14.4)years, 63% male, 72% CIDP(28% MMN), 97% IVIg(3% SCIg). Dose = 1.57(0.79)g/kg/month or 97.1(37.3)g/infusion, frequency:3.9(1.4) weeks. Relative IgA deficiency was noted in 2 individuals (prevalence:2.2%, 95%C.I.:0-5.2) who received a combined total of 38 infusions(3800 g IVIg) without adverse event. No clinically significant episodes of haemolysis, neutropenia, thrombocytopenia or AKI occurred in relation to treatment. An asymptomatic drop>10 g/L haemoglobin(Hb) occurred in 3.5%(95%CI:2.7-4.3) of treatment episodes in 38 individuals, mean reduction:17.7(7.4)g/L; lowest Hb:86 g/L. Lower pre-treatment haemoglobin correlated with risk of recurrent Ig-related drop(p:0.007). Two patients with chronic renal failure(stage 1 and 3) received 28(IV) and 104(SC) infusions respectively(6416 g) without impact on estimated glomerular filtration rate(eGFR). CONCLUSIONS: No clinically significant Ig-related episodes of haemolysis or AKI were identified in this representative cohort. This suggests that routine monitoring is not essential in long-term Ig use but should be considered when clinically indicated.

25-Hydroxy vitamin D3 serum concentration in dogs with acute polyradiculoneuritis compared to matched controls.

OBJECTIVES: To determine if dogs with acute polyradiculoneuritis have lower serum 25-hydroxy vitamin D3 concentration compared to a control group of dogs with idiopathic epilepsy. MATERIALS AND METHODS: Retrospective case-control study of 21 dogs with acute canine polyradiculoneuritis and 21 control dogs with idiopathic epilepsy matched for year and season of presentation from a referral hospital population in the UK. Serum concentration of 25-hydroxy vitamin D3 was compared between groups using Student's t-test. RESULTS: Dogs with acute canine polyradiculoneuritis had significantly lower (P=0·033) serum 25-hydroxy vitamin D3 concentration (87·1 nmol/L ±55·4 nmol/L) compared to a control group with idiopathic epilepsy (113 nmol/L ±66·3 nmol/L). CLINICAL SIGNIFICANCE: The cause and clinical significance of the altered vitamin D status in dogs with acute polyradiculoneuritis are not clear and require further investigation. Our findings pave the way for improved understanding of acute canine polyradiculoneuritis and, potentially, improved clinical management, if a causal role for 25-hydroxy vitamin D3 is defined.

Immunohistochemistry and electrophysiological findings in swine abattoir workers with immune-mediated polyradiculoneuropathy.

IMPORTANCE: Workers exposed to aerosolized brain in a swine-processing plant developed immune-mediated polyradiculoneuropathy (IP) possibly triggered by an immune response. OBJECTIVE: Immunohistochemistry results were correlated with electrophysiological variables to examine the immunopathogenesis of this disorder. DESIGN/SETTING: Laboratory studies used normal nerve tissue that was exposed to sera from 12 IP patients; 10 exposed controls; and 10 unexposed controls. Clinical and electrophysiological data from IP patients were obtained from medical record reviews. MAIN OUTCOME MEASURES: Analysis included electromyography results of IP patients and nerve conduction studies examining CMAP amplitude, distal motor latency, motor conduction velocity, F-wave latency, sensory nerve action potential amplitude, and sensory nerve conduction velocity. Case and control results were compared relative to distance from exposure. RESULTS: Electrodiagnostic findings revealed prolongation of the distal and f-wave latencies suggestive of demyelination at the level of the nerve root and distal nerve terminals. Immunohistochemical results identified an antibody to the peripheral nerve, with staining at the level of the axolemma. Thus, IP may be a primary axonopathy with secondary paranodal demyelination causing the conduction changes. Staining of the distal and proximal portions of the nerve appears consistent with easier access through the blood-nerve barrier. CONCLUSIONS AND RELEVANCE: IP is an immune-mediated neuropathy related to antibodies to an axon-based antigen on peripheral nerves. Secondary paranodal demyelination is likely. Further studies to identify the primary axonal antigenic target would be useful.

Varied immuno-related adverse events induced by immune-check point inhibitors - Nivolumab-associated psoriasiform dermatitis related with increased serum level of interleukin-6.

Nivolumab is a standard recombinant antibody treatment for patients with malignant melanoma (MM), which functions as an immune checkpoint inhibitor by blocking the programmed cell death-1 (PD-1) pathway in T cells. However, it leads to various immune-related adverse events (irAEs), and also exacerbates underlying autoimmune diseases. Herein we report cases of MM with irAE. Case 1: A 69-year-old woman with MM developed destructive thyroiditis resulting in hypothyroidism after 3 doses of nivolumab, and had been treated with thyroid gland auxiliary therapy. Case 2: A 80-year-old man with MM developed an acute onset of hyperthyroidism after 4 doses of nivolumab. Case 3: A 85-year-old woman with MM developed polyradiculoneuropathy resulting in somatosensory disorder and muscle weakness after 2 doses of nivolumab, and had been treated with intravenous immunoglobulin and oral predonisolone (40 mg/day). Case 4: A 77-year-old man with MM developed psoriasiform dermatitis after local injections of IFN-ß and 11 doses of nivolumab. Case 5: Case 2 also developed psoriasiform dermatitis. We analyzed serum levels of inflammatory cytokines in MM patients before/after treatments with nivolumab. All six patients who developed psoriasiform dermatitis with/without anamnesis of psoriasis after treatment with nivolumab, and all seven patients with other irAE exhibited increased serum IL-6 levels after nivolumab treatment, while decreased serum levels of IL-6 were observed in 5 of 7 non-afflicted MM patients. In addition, MM patients who achieved good responses to nivolumab significantly exhibited decreased serum TNF-α levels after nivolumab treatment compared to progressive MM patients.

Characterization of neuropathies associated with elevated IgM serum levels.

BACKGROUND: In contrast to the IgM monoclonal gammopathies the neuropathy associated with polyclonal IgM gammopathy has not been well characterized. OBJECTIVE: To characterize the neuropathy in patients with elevated serum IgM. DESIGN: Retrospective review. SETTING: Academically based neuropathy center. PATIENTS: 45 patients with elevated quantitative immunoglobulin M were identified. MAIN OUTCOME MEASURES: Patients are described with regard to clinical phenotype, electrodiagnostic features of demyelination or focality, presence of IgM monoclonal gammopathy, and presence of autoantibody activity. RESULTS: Elevated IgM levels occurred in 45 (11.5%) of 391 patients. Of these, 24 (53%) had polyclonal gammopathy and 21 (47%) had an IgM monoclonal gammopathy. Anti-nerve antibodies occurred in 14/21 (67%) of patients with monoclonal gammopathy, as compared to 1/24 (4%) with polyclonal gammopathy. Clinically, most patients in all groups had a predominantly large fiber sensory neuropathy. Thirty patients underwent electrodiagnostic testing. Of these, 22/30 (73%) fulfilled at least one published criteria for CIDP, including 92% of the monoclonal gammopathy patients and 59% of the polyclonal gammopathy patients. Fifteen of the 30 patients had evidence of focality or multifocality, with 14 of these 15 showing evidence of demyelination. CONCLUSIONS: Monoclonal and polyclonal IgM patients have similar distributions of neuropathy phenotypes. Neuropathy in association with elevated serum IgM, with or without monoclonal gammopathy or autoantibody activity, is more likely to be demyelinating or multifocal. Serum quantitative IgM level and immunofixation in neuropathy patients may aid in identification of an immune mediated or a demyelinating component.

Effects in vitro of serum from patients with Landry-Guillain-Barré syndrome of alcoholic peripheral neuropathy on outgrowth of rat dorsal root ganglia.

Cultures of three-day-old rat dorsal root ganglia were grown in control media containing human cord serum or in experimental media containing serum from patients with Landry-Guillain-Barré syndrome, alcoholic peripheral neuropathy, or normal adults. Analysis of variance in control cultures showed that there was a falloff of mean outgrowth length during active myelination by fourteen days, while cultures grown in the three experimental media had a greater outgrowth length and did not form myelin.

Elevated neopterin levels in Guillain-Barré syndrome. Further evidence of immune activation.

Neopterin is a by-product of guanosine triphosphate metabolism and is produced by macrophages in response to lymphocytic activation. We have studied serum neopterin levels in patients with Guillain-Barré syndrome to obtain further evidence of immune activation in this disease. Serum neopterin levels were significantly elevated in patients with Guillain-Barré syndrome compared with patients with other peripheral neuropathies and multiple sclerosis and with healthy control subjects. Serial analysis demonstrated that as neopterin levels fell, the clinical status of the patients with Guillain-Barré syndrome improved and soluble interleukin 2 receptor levels dropped. Thus, lymphocytic and macrophage activation may play a role in the pathogenesis of Guillain-Barré syndrome.

Cerebrospinal fluid interleukins, immunoglobulins, and fibronectin in neuroborreliosis.

Intrathecal synthesis of IgM and IgG, oligoclonal immunoglobulin bands, and the levels of fibronectin, soluble interleukin 2 receptor, interleukin 6, and tumor necrosis factor alpha were investigated with the use of enzyme-linked immunosorbent assay in 46 paired cerebrospinal fluid and serum samples from 32 patients with meningopolyradiculoneuritis due to Borrelia burgdorferi (Lyme borreliosis stage 2). Cerebrospinal fluid and serum interleukin 6, although not specific for neuroborreliosis, were good indicators of disease activity, while the serum soluble interleukin 2 receptor level was only mildly elevated. Tumor necrosis factor alpha was never detected in cerebrospinal fluid or serum specimens, and cerebrospinal fluid IgM, IgM index, and cerebrospinal fluid IgM/cerebrospinal fluid IgG ratios were significantly higher than in all other neuroimmunologic disorders evaluated and may be valuable diagnostic indicators for neuroborreliosis. The estimation of intrathecally synthesized IgG and IgM fractions for the differential diagnosis of neuroimmunologic disorders did not add to IgG and IgM index calculations.

GM1b is a new member of antigen for serum antibody in Guillain-Barré syndrome.

Serum antibody from some patients with Guillain-Barré syndrome recognized an antigen of a minor component in human brain monosialoganglioside fraction. We purified that antigen, which migrated at a position slightly lower than that of GM1 on a thin-layer chromatogram (TLC), by using Iatrobeads column chromatography and preparative TLC. Structural analyses, including fast atom bombardment mass spectrometry, showed it to be GM1b. An enzyme-linked immunosorbent assay (ELISA) using purified GM1b showed that anti-GM1b antibody was present in 22 of 104 cases tested. No anti-GM1b antibody was present in the sera from control patients with other diseases or from the normal controls. Four sera recognized only GM1b among the 11 ganglioside antigens tested. The other 18 sera had antibodies to other antigens, most of which shared no terminal epitope with GM1b. Eight of nine sera samples with anti-GalNAc-GD1a antibody also had anti-GM1b antibody. Antibody to a minor monosialoganglioside, GM1b, was found to be a useful diagnostic marker for Guillain-Barré syndrome. Further study is needed to determine whether this antibody plays a role in the pathogenetic mechanism of the syndrome.

Serum levels of soluble E-selectin (ELAM-1) in immune-mediated neuropathies.

Adhesion molecules are critically involved in inflammatory responses. We studied serum concentrations of the soluble form of E-selectin (endothelial-leukocyte adhesion molecule-1, ELAM-1) in 187 patients with neuropathies of diverse etiology, 54 patients with other noninflammatory, nondemyelinating neurologic disorders, and 15 healthy controls. Serum E-selectin levels, quantitated by a two-site enzyme-linked immunosorbent assay, were significantly increased in 126 patients with Guillain-Barré syndrome (GBS) (mean +/- SD, 45.1 +/- 16.3 ng/ml) and 13 patients with vasculitic neuropathies (47.1 +/- 19.1ng/ml) compared with patients with other neurologic diseases (19.8 +/- 7.4 ng/ml) and healthy controls (21.9 +/- 8.1 ng/ml). In GBS, E-selectin levels were temporally related to disease activity. Cytokine-mediated upregulation of E-selectin may be important in homing and attachment of leukocytes to endoneurial endothelial cells. Raised E-selectin concentrations probably reflect endothelial cell activation occurring early in the sequence of immunopathologic events culminating in peripheral nerve damage.

Extra- and intrathecal production of antinerve and antibrain antibodies in Guillain-Barré syndrome: evaluation by an antibody index.

In serum and CSF samples from 19 patients with the Guillain-Barré syndrome (GBS), we assayed complement-fixing autoantibodies that react with peripheral and central nervous tissue. About two thirds of the serum and CSF samples reacted with preparations of one or both tissues. The distribution of antibodies, evaluated by the antibody index (CSF/serum titer divided by CSF/serum albumin), suggested predominantly extrathecal production in most patients, but an intrathecal contribution was also seen. Thus, the possible pathogenic effects of antineural antibodies in GBS may be exerted on both sides of the blood-brain barrier.

Clinical correlation with serum-soluble interleukin-2 receptor levels in Guillain-Barré syndrome.

In patients with Guillain-Barré syndrome (GBS) soluble interleukin-2 receptor (sIL-2R) levels were elevated compared with those of patients with other neurologic diseases (OND), and of healthy controls. Smaller increases in sIL-2R levels occurred in OND patients compared to healthy subjects. Monitoring of GBS patients clearly demonstrated that decreases in sIL-2R levels correlated with clinical recovery. Thus, T-cell activation may be relevant in the pathogenesis of GBS.

T cell activation in Guillain-Barré syndrome and in MS: elevated serum levels of soluble IL-2 receptors.

Guillain-Barré syndrome (GBS), chronic idiopathic demyelinating polyradiculoneuropathy (CIDP), and multiple sclerosis (MS) are disorders with presumed immunopathogenesis. To obtain evidence for T cell activation, we determined serum concentrations of soluble interleukin-2 receptors (sIL-2 R) in 50 patients with GBS, 24 with CIDP, and 54 with MS. Both in GBS and clinically active MS sIL-2 R levels were markedly increased compared with those in patients with other neurologic diseases. Four of 24 CIDP patients had abnormally increased sIL-2 R concentrations. sIL-2 R concentrations decreased with clinical improvement in serial samples taken from GBS patients, but were not otherwise correlated with disease severity. These data establish that T cells are activated in GBS and some patients with CIDP, and corroborate earlier evidence that activated T cells are circulating in the blood of MS patients.

Serum and CSF levels of soluble intercellular adhesion molecule-1 (ICAM-1) in inflammatory neurologic diseases.

Intercellular adhesion molecule-1 (ICAM-1), a cell surface receptor important for cellular interactions in immune responses, especially leukocyte trafficking into inflamed tissue, is released in a soluble form (sICAM-1) into the extracellular space. In this study, we measured sICAM-1 in paired serum and CSF samples from patients with inflammatory diseases of the nervous system (IND) and calculated a sICAM-1 index as a measure of the intrathecal release of ICAM-1. In comparison with noninflammatory neurologic disease (NIND) controls, we found increased sICAM-1 index levels in viral meningoencephalitis, bacterial meningitis and, to a lesser degree, multiple sclerosis but not in Guillain-Barré syndrome. Serial examination of viral meningoencephalitis patients in most cases showed a decrease of sICAM-1 index in parallel with falling cell counts and clinical improvement. Except for those in bacterial meningitis, sICAM-1 serum levels of IND patients were not significantly different from those of NIND controls. The increased intrathecal release of sICAM-1 in viral meningoencephalitis and bacterial meningitis most likely reflects activation of macrophages and lymphocytes and provides evidence for a strong local immune response that itself, in addition to the infectious agent, may damage nervous tissue.

Tryptophan-immobilized column adsorbs immunoglobulin G anti-GQ1b antibody from Fisher's syndrome: A new approach to treatment.

Sera from patients with Fisher's syndrome in the acute phase contain immunoglobulin (Ig)G anti-GQ1b ganglioside antibody. Removal of the autoantibody should lead to earlier recovery with less residual neurologic involvement. A tryptophan- or phenylalanin-immobilized polyvinyl alcohol gel column (IM-TR 350 or IM-PH 350) semiselectively adsorbs such autoantibodies as rheumatoid factor, anti-DNA antibody, or anti-acetylcholine receptor antibody. A batchwise adsorption test showed that an IM-TR gel adsorbed a larger amount of the IgG anti-GQ1b antibody than did an IM-PH column. Several patients with Fisher's syndrome therefore were given immunoadsorbent therapy using the IM-TR column without adverse reactions. An ex vivo plasma perfusion study done with the IM-TR column confirmed that it effectively adsorbs the IgG anti-GQ1b antibody. Results of adsorption tests done with various amino acid-immobilized gels suggest that both the hydrophobic force of the side chain and the anionic charge of the carboxylic acid in tryptophan are important in the adsorption of the autoantibody by the IM-TR gel. Immunoadsorption using the IM-TR column, which does not need replacement fluids, offers an alternative type of plasmapheresis for Fisher's syndrome.

Serum anti-GQ1b IgG antibody is associated with ophthalmoplegia in Miller Fisher syndrome and Guillain-Barré syndrome: clinical and immunohistochemical studies.

To determine the significance of serum anti-GQ1b IgG antibody, we studied the disease spectrum associated with this antibody and GQ1b epitope in the human nervous system. We examined sera from 19 patients with typical Miller Fisher syndrome (MFS), five patients with acute postinfectious ophthalmoplegia without ataxia (atypical MFS), six patients with Guillain-Barré syndrome (GBS) with ophthalmoplegia (GBS-OP[+]), and 23 patients with GBS without ophthalmoplegia (GBS-OP[-]). We also examined sera from 84 patients with other neurologic or non-neurologic disorders and from 16 normal control subjects. Eighteen of the 19 patients with typical MFS, all the patients with atypical MFS, and five of the six patients with GBS-OP(+) had increased anti-GQ1b IgG activity in ELISA, but none of the patients in the other groups, including GBS-OP(-), had it. All the patients' sera that had anti-GQ1b IgG antibody showed anti-GT1a IgG activity. Results of absorption studies suggested that the same antibody reacted with GQ1b and GT1a. An anti-GQ1b mouse monoclonal antibody immunostained the paranodal regions of the extramedullary portion of the human oculomotor, trochlear, and abducens nerves. Biochemical analysis showed that the human oculomotor nerve contained a larger amount of GQ1b than did the ventral and dorsal roots of the spinal cord. We conclude that serum IgG antibody against GQ1b is very closely associated with acute postinfectious ophthalmoplegia in MFS and GBS.