PubMed Health⌕ Search

Biomedical subjects

Norman Latov

Publications and source records attributed to Norman Latov.

At least 19 recordsLinked to original sources

Transglutaminase-independent binding of gliadin to intestinal brush border membrane and GM1 ganglioside.

Anti-ganglioside antibodies have been described in celiac disease or gluten sensitivity, in conjunction with the presence of central and peripheral nervous system deficits. The observed antibody reactivity to gangliosides is postulated to be related to the anti-gliadin immune response, either through antigenic mimicry, or by formation of gliadin-ganglioside complexes and haptenization. We examined the possibility of the presence of ganglioside-like epitopes in gliadin, as well as the potential for complex formation between gliadin and GM1 ganglioside. Low levels of glycosylation were present in gliadin, but ganglioside-like carbohydrate epitopes were not detected. However, gliadin was found to bind to GM1 ganglioside and to the GM1-rich intestinal brush border membrane. The described complex formation and possible haptenization of GM1 by gliadin may be responsible for driving the anti-ganglioside antibody response in some patients with gluten sensitivity. Furthermore, binding of gliadin to GM1 on the intestinal epithelium might have a role in the anti-gliadin immune response and contribute to the intestinal inflammatory reaction in celiac disease.

Animals↗

Small-fiber neuropathy/neuronopathy associated with celiac disease: skin biopsy findings.

BACKGROUND: Celiac disease (CD) is increasingly recognized in North America and is associated with a peripheral neuropathy. OBJECTIVE: To report the clinical characteristics and skin biopsy results in patients with CD and small-fiber neuropathy symptoms. DESIGN: Case series. SETTING: Academic peripheral neuropathy clinic. PATIENTS: Eight patients with CD and neuropathy symptoms. Intervention Three-millimeter punch biopsy using the panaxonal marker protein gene product 9.5 to assess epidermal nerve fiber (ENF) density and a gluten-free diet. MAIN OUTCOME MEASURE: Clinical data and ENF density. RESULTS: All patients had asymmetric numbness and paresthesias. Three had more prominent involvement of hands than feet, and 3 had facial numbness. Celiac disease was diagnosed in 5 after their neuropathy began. The following serum antibody levels were elevated: tissue transglutaminase (n = 6), IgA gliadin (n = 4), and IgG gliadin (n = 7). Results of nerve conduction studies were normal in 7 patients. One patient had mildly reduced sural amplitudes. The ENF density was reduced in 5 patients. The ENF density was at the low limit of the normal range in 3 additional patients, 2 of whom had morphologic changes in axons. Three patients had decreased ENF density at the thigh or forearm, which was more severe than at the distal leg, compatible with a non-length-dependent process. Four reported improvement with a gluten-free diet. One had no improvement after 4 months. Symptoms developed in 2 while receiving a gluten-free diet. CONCLUSIONS: Patients with CD may have a neuropathy involving small fibers, demonstrated by results of skin biopsy. The pattern of symptoms, with frequent facial involvement and a non-length-dependent pattern on skin biopsy findings, suggests a sensory ganglionopathy or an immune-mediated neuropathy. Improvement of symptoms in some patients after initiating a gluten-free diet warrants further study.

Celiac Disease↗

Peripheral Neuropathy and Celiac Disease.

Peripheral neuropathy (PN) is one of the most frequently reported neurologic manifestations associated with celiac disease (CD), a multigenetic, T-cell-mediated autoimmune disorder that results from a loss of tolerance to gluten. Sensory axonal and small fiber sensory polyneuropathies are the most frequently reported PN subtypes. Multifocal motor or sensorimotor neuropathies and a more fulminant neuropathy, associated with ataxia and other neurologic manifestations, also have been reported. The effect of a gluten-free diet on CD-associated PN has not been studied systematically or prospectively; nevertheless, a gluten-free diet currently is the cornerstone of therapy. Although idiopathic ataxia associated with anti-gliadin antibodies and other neurologic complications have been reported to respond to this diet; there is data that indicate that neurologic manifestations may develop or persist, independent of gluten exposure. There is evidence to suggest that inflammatory processes may be involved. Immunomodulatory agents (such as intravenous immunoglobulin or infliximab), described to be beneficial in the treatment of refractory CD or CD-associated ataxia, may have a role in the management of CD-associated PN.

Journal Article↗

Distal symmetrical polyneuropathy: a definition for clinical research. A report of the American Academy of Neurology, the American Association of Electrodiagnostic Medicine, and the American Academy of Physical Medicine and Rehabilitation.

The objective of this report was to develop a case definition of "distal symmetrical polyneuropathy" to standardize and facilitate clinical research and epidemiologic studies. A formalized consensus process was employed to reach agreement after a systematic review and classification of evidence from the literature. The literature indicates that symptoms alone have relatively poor diagnostic accuracy in predicting the presence of polyneuropathy; signs are better predictors of polyneuropathy than symptoms; and single abnormalities on examination are less sensitive than multiple abnormalities in predicting the presence of polyneuropathy. The combination of neuropathic symptoms, signs, and electrodiagnostic findings provides the most accurate diagnosis of distal symmetrical polyneuropathy. A set of case definitions was rank ordered by likelihood of disease. The highest likelihood of polyneuropathy (useful for clinical trials) occurs with a combination of multiple symptoms, multiple signs, and abnormal electrodiagnostic studies. A modest likelihood of polyneuropathy (useful for field or epidemiologic studies) occurs with a combination of multiple symptoms and multiple signs when the results of electrodiagnostic studies are not available. A lower likelihood of polyneuropathy occurs when electrodiagnostic studies and signs are discordant. For research purposes, the best approach to defining distal symmetrical polyneuropathy is a set of case definitions rank ordered by estimated likelihood of disease. The inclusion of this formalized case definition in clinical and epidemiologic research studies will ensure greater consistency of case selection.

Electrodiagnosis↗

Central nervous system manifestations of rheumatologic diseases.

PURPOSE OF REVIEW: To summarize the current literature on central nervous system manifestations of vasculitides and connective tissue diseases. RECENT FINDINGS: There have been advances in understanding the mechanisms behind the initiation and perpetuation of inflammatory processes in vasculitic neuropathy. Clinically relevant data have been obtained on the predictive criteria for a positive biopsy result in giant cell arteritis, the imaging characteristics of primary angiitis of the central nervous system, and Behçet disease, and the clinical and radiologic features of neuro-Behçet disease. There is more clarity about the central nervous system syndromes attributable to systemic lupus erythematosus and new insights into the central mechanisms involved in the manifestations of Sjögren syndrome and rheumatoid arthritis. Novel immunomodulatory agents, such as infliximab, have shown some benefit in rheumatoid vasculitis and Sjögren syndrome. SUMMARY: A better understanding of the clinical, radiographic, and serologic characteristics of various central nervous system complications of rheumatologic diseases has been gained in the past year. Recent advances in understanding the pathophysiology of peripheral nervous system complications and their treatment may affect the management of the central nervous system complications.

Antibodies, Monoclonal↗

Altered subicular MAP2 immunoreactivity in schizophrenia.

We wished to test independently a previously reported loss of subicular microtubule-associated protein 2 (MAP2) in the brains of deceased individuals who had suffered from schizophrenia, and to determine whether there were any clinical characteristics attached to such a loss. Immunohistochemistry for MAP2 was examined in the hippocampal region from 94 psychiatric patients: 64 with a primary diagnosis of schizophrenia or schizoaffective disorder, 12 with a primary diagnosis of major depressive or bipolar disorders, and 18 with a primary diagnosis of dementia; and from 17 individuals without psychiatric disease. Lifelong symptomatology was evaluated with the modified Diagnostic Evaluation After Death. Subicular MAP2 immunoreactivity was prominently depressed in 20% of schizophrenia cases, 8% of mood disorder cases, 22% of dementia cases, and in no nonpsychiatric cases. Among dementia cases, those with loss of subicular MAP2 immunoreactivity displayed more subicular gliosis, while among the schizophrenia cases, there was no such association. Among schizophrenia subjects, loss of subicular MAP2 immunoreactivity was associated with fewer positive and negative symptoms over the course of the illness. Subicular MAP2 immunoreactivity is markedly diminished in a significant proportion of individuals chronically institutionalized for schizophrenia, and this does not represent a generalized destruction of subicular neurons. In contrast, among individuals institutionalized for dementia, loss of subicular MAP2 immunoreactivity is accompanied by gliosis. The loss of MAP2 immunoreactivity is associated with fewer clinical symptoms, suggesting that it may represent an adaptive response to schizophrenia. The chemical or structural abnormalities underlying decreased MAP2 immunoreactivity in schizophrenia remain to be determined.

Aged↗

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.

Antibodies, Monoclonal↗

Gene expression profiling in chronic inflammatory demyelinating polyneuropathy.

Gene expression in archived frozen sural nerve biopsies of patients with chronic inflammatory demyelinating polyneuropathy (CIDP) was compared to that in vasculitic nerve biopsies (VAS) and to normal nerve (NN) by DNA microarray technology. Hierarchical clustering analysis demonstrated distinct gene expression patterns distinguishing these disease groups. Of particular interest were: (1) Tachykinin precursor 1, which may be involved in pain mediation; (2) Stearoyl-CoA-desaturase, which may be a marker for remyelination and (3) the Allograft Inflammatory Factor 1 (AIF-1), a modulator of immune response during macrophage activation. Differential gene expression may help distinguish between CIDP, VAS and NN in sural nerve biopsies and identify genes that may be involved in disease pathogenesis.

Adult↗

Antibodies against OspA epitopes of Borrelia burgdorferi cross-react with neural tissue.

Neurological sequela of chronic Lyme disease include encephalopathy, myelopathy and peripheral neuropathy. These have generally been attributed to either persistent infection or pathogen-induced autoimmunity. In this study, we investigated the presence of cross-reactive human neural epitopes that share amino acid sequences with Borrelia burgdorferi OspA protein. Sequence similarity analysis was carried out by searching known cDNA sequences from brain tissue. The cDNA database search yielded three sequences that were identical to sequences in OspA. Corresponding peptides were synthesized and antibodies were generated against them in rabbits. Antibodies against two of the homologous OspA peptides were found to react with neurons in human brain, spinal cord and dorsal root ganglia by immunohistochemistry.

Animals↗

Induction of human IgM and IgG anti-GM1 antibodies in transgenic mice in response to lipopolysaccharides from Campylobacter jejuni.

Campylobacter jejuni lipopolysaccharides (LPS) are implicated in the development of autoantibodies to GM1 ganglioside in patients with neuropathy following C. jejuni infection. CjLPS bears oligosaccharides that are cross reactive with GM1 ganglioside and presumably exerts its effects via molecular mimicry. To study the mechanisms that are involved in development of the autoantibody response, a transgenic mouse line was developed that expresses an IgM anti-GM1 antibody derived from a patient with multifocal motor neuropathy (MMN). In vivo stimulation of the transgenic mice with C. jejuni lipopolysaccharides (CjLPS), but not of wild-type mice readily elicited high serum titers of anti-GM1 IgM antibodies, followed by IgG anti-GM1 antibodies after two booster injections. In in vitro experiments, CjLPS stimulated the transgenic B-cells at lower concentration than control LPS. The increased sensitivity to CjLPS and the induction of IgG anti-GM1 by CjLPS but not control LPS are consistent with a mechanism of B-cell activation that involves both the LPS and the antigen-specific surface Ig receptors, with possible participation of T-cells.

Animals↗

Sensory CIDP presenting as cryptogenic sensory polyneuropathy.

The objective of this study was to report that patients with chronic inflammatory demyelinating polyneuropathy (CIDP) can present with a clinical picture of cryptogenic sensory neuropathy. Patients with distal sensory neuropathy and electrodiagnostic studies that are minimally abnormal or consistent with an axonal pathology are usually diagnosed as having cryptogenic sensory neuropathy if no cause for neuropathy can be found. Some of these patients, however, may have sensory CIDP. We reviewed the records of eight patients with CIDP, diagnosed by sural nerve biopsy, who presented with sensory neuropathy and electrodiagnostic studies that were minimally abnormal or revealed changes consistent with axonal neuropathy. All patients reported distal numbness and paresthesias and, on examination, had predominantly large fiber distal sensory loss and normal muscle strength. In most patients, deep tendon reflexes were reduced or absent. Sural nerve biopsies in all patients were consistent with chronic myelinopathy, with quantitative teased fiber analysis revealing segmental remyelination in 13-40% of the fibers. The four patients who received IVIg therapy had improved sensation and gait. Of the remaining four patients, one is being followed, one had spontaneous remission, one was lost to follow-up, and one, with contraindications to therapy, reported disease progression. Sensory CIDP may present as cryptogenic sensory polyneuropathy with normal or axonal electrophysiologic features. Sural nerve biopsy should be considered in patients with progressive, predominantly large fiber sensory neuropathy of otherwise unknown etiology, as they may have sensory CIDP that responds to therapy.

Adult↗

Neuropathy and cognitive impairment following vaccination with the OspA protein of Borrelia burgdorferi.

Neurological syndromes that follow vaccination or infection are often attributed to autoimmune mechanisms. We report six patients who developed neuropathy or cognitive impairment, within several days to 2 months, following vaccination with the OspA antigen of Borrelia burgdorferi. Two of the patients developed cognitive impairment, one chronic inflammatory demyelinating polyneuropathy (CIDP), one multifocal motor neuropathy, one both cognitive impairment and CIDP, and one cognitive impairment and sensory axonal neuropathy. The patients with cognitive impairment had T2 hyperintense white matter lesions on magnetic resonance imaging. The similarity between the neurological sequelae observed in the OspA-vaccinated patients and those with chronic Lyme disease suggests a possible role for immune mechanisms in some of the manifestations of chronic Lyme disease that are resistant to antibiotic treatment.

Adult↗

Etanercept (Enbrel) therapy for chronic inflammatory demyelinating polyneuropathy.

Patients with chronic inflammatory demyelinating polyneuropathy (CIDP) and/or variants who were refractory or intolerant of standard therapies were treated with etanercept, 25 mg twice per week. Ten patients underwent treatment, and manual muscle strength, sensory thresholds and functional abilities were tested prior to and 4-6 months after initiating therapy. Three patients had significant improvement and three others had possible improvement. Based on these preliminary observations, treatment with etanercept may be considered in patients with CIDP, who cannot undergo standard therapies, although its efficacy in CIDP needs to be examined in a double-blinded, controlled clinical trial.

Adult↗

Anti-ganglioside antibodies in idiopathic and hereditary cerebellar degeneration.

Cerebellar degeneration has been associated with gluten sensitivity and celiac disease. Patients with celiac disease may have neuropathy and antibodies to gangliosides. The authors investigated the presence of antiganglioside antibodies in 22 patients with hereditary and nonhereditary ataxia and found 64% reactive in a novel agglutination test.

Aged↗