Assessment of Expression of SOCS Genes in Acquired Immune-Mediated Polyneuropathies.

Acquired immune-mediated polyneuropathies are classified to some subtypes among them are acute and chronic inflammatory demyelinating polyradiculoneuropathies (AIDP and CIDP). These two conditions share some common signs and underlying mechanisms. Based on the roles of Suppressor of cytokine signaling (SOCS) genes in the modulation of immune system reactions, these genes might be involved in the pathogenesis of these conditions. We evaluated expression of SOCS1-3 and SOCS5 genes in the leukocytes of 32 cases of CIDP, 19 cases of AIDP and 40 age- and sex-matched controls using real time PCR method. The Bayesian regression model was used to estimate differences in mean values of genes expressions between cases and control group. Expression levels of SOCS1 and SOCS2 were significantly lower in male patients compared with controls. This sex-specific pattern was also observed for SOCS3 down-regulation. Based on the area under curve values in Receiver Operating Characteristics (ROC) curve, diagnostic powers of SOCS1, SOCS2, SOCS3 and SOCS5 genes in the mentioned disorder were 0.61, 0.73, 0.68 and 0.58, respectively. Expression of none of genes was correlated with age of enrolled cases. The current study shows evidences for participation of SOCS genes in the pathophysiology of acquired immune-mediated polyneuropathies.

Virus discovery in chronic inflammatory demyelinating polyneuropathy.

The events triggering and/or sustaining the auto-immune response underlying chronic inflammatory demyelinating polyneuropathy (CIDP) are unknown. Similar to Guillain-Barré syndrome (GBS), a viral infection might play a role in CIDP. In this study, an virus detection method (VIDISCA-next generation sequencing) capable of detecting known and unknown viruses, was used to analyze the virome in serum of 47 CIDP patients at different time points of the disease and, when available, in cerebrospinal fluid (CSF) samples (N: 17). Serum samples of GBS patients (N:24) and healthy controls (N:114) were used for comparisons. In 5/47 (10.6%; 95% CI: 4-23) CIDP samples, 10/24 (42%; 95% CI: 22-63) GBS samples and 32/114 (28.1%; 95% CI: 20-37) healthy controls samples, anelloviruses were detected, generally regarded as a non-pathogenic species. Parvovirus B19 and GB virus C were found in two CIDP samples (4%). Parvovirus B19, HIV-1 and GB virus C were found in three GBS samples (13%). In 2/17 CIDP CSF samples, an anellovirus and polyomavirus were detected, probably due to contamination during lumbar puncture. No sequences of other viruses were detected in serum or CSF. A (persistent) viral infection sustaining the auto-immune response in CIDP seems therefore unlikely.

Expression Analysis of Protein Inhibitor of Activated STAT in Inflammatory Demyelinating Polyradiculoneuropathy.

Protein inhibitors of activated STAT (PIAS) are involved in the regulation of the JAK/STAT signaling pathway and have interactions with NF-κB, p73 and p53. These proteins regulate immune responses; therefore dysregulation in their expression leads to several immune-mediated disorders. In the present study, we examined expression of PIAS1-4 in peripheral blood of patients with acute/chronic inflammatory demyelinating polyradiculoneuropathy (AIDP/CIDP) compared with healthy subjects. We demonstrated down-regulation of all PIAS genes in both AIDP and CIDP cases compared with controls. Similarly, comparisons in gender-based groups revealed down-regulation of these gene0s in patients of each gender compared with gender-matched controls. There was no significant difference in expression of PIAS genes between AIDP and CIDP cases. Based on the area under the receiver operating characteristic curves, PIAS1-4 genes could distinguish between inflammatory demyelinating polyradiculoneuropathy and healthy status with accuracy values of 0.87, 0.87, 0.79 and 0.80, respectively. In differentiation between AIDP cases and healthy controls, these values were 0.92, 0.92, 0.83 and 0.86, respectively. Finally, PIAS1-4 genes could discriminate CIDP from healthy status with accuracy values of 0.82, 0.83, 0.75 and 0.75, respectively. The current study underscores the role of PIAS genes in the pathogenesis of inflammatory demyelinating polyradiculoneuropathy and their potential usage as biomarkers.

Evaluation of Expression of STAT Genes in Immune-Mediated Polyneuropathies.

Immune-mediated polyneuropathies are acquired conditions that can be categorized to acute and chronic forms based on the disease course. Although the basic mechanism of these conditions has not been clarified yet, genes that regulate immune responses are putative contributors in their development. In the current study, we assessed expression of signal transducer and activator of transcription (STAT)1-3 and STAT5a genes in peripheral blood of 51 patients and 40 healthy subjects. Expression of STAT1 was higher in female patients compared with female controls (Posterior Beta = 3.622, P = 0.044). The gender*group interaction was significant for this gene which indicates different direction of association in males and females. Expressions of other STAT genes were not different between cases and controls. The diagnostic power of STAT1 in female subjects was estimated to be 0.72 with sensitivity of 68.75% and specificity of 84.62%. There was no significant correlation either between expression of different STAT genes or between their expression and age of study participants. The current study potentiates STAT1 as a putative factor in the pathophysiology of acquired immune-mediated polyneuropathies in females and suggests conduction of further functional studies to elaborate the molecular mechanism of this contribution.

Immunoglobulin administration for the treatment of CIDP: IVIG or SCIG?

Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired neurological disorder characterized clinically by weakness and impaired sensory function evolving over 2 months or more, loss or significant decrease in deep tendon reflexes, and by electrophysiological evidence of peripheral nerve demyelination. Expeditious diagnosis and treatment of CIDP early in the disease course is critical such that irreversible disability can be avoided. Intravenous immunoglobulin (IVIG) is one first-line and maintenance therapy option for CIDP. The US Food & Drug Administration's (FDA's) approval of subcutaneous immunoglobulin (SCIG) in 2018 provides patients with CIDP more treatment options for maintenance therapy. The different options for administration of IG treatment create the need for information to assist clinicians and patients in choosing the optimal therapeutic approach. Considerations for pharmacokinetics, administration procedures, adverse events, patient variables, and cost will all be discussed in this article.

Increased IP-10 production by blood-nerve barrier in multifocal acquired demyelinating sensory and motor neuropathy and multifocal motor neuropathy.

OBJECTIVE: Dysfunction of the blood-nerve barrier (BNB) plays important roles in chronic inflammatory demyelinating polyneuropathy (CIDP) and multifocal motor neuropathy (MMN). The aim of the present study was to identify the candidate cytokines/chemokines that cause the breakdown of the BNB using sera from patients with CIDP and MMN. METHODS: We determined the levels of 27 cytokines and chemokines in human peripheral nerve microvascular endothelial cells (PnMECs) after exposure to sera obtained from patients with CIDP variants (typical CIDP and multifocal acquired demyelinating sensory and motor neuropathy [MADSAM]), MMN and amyotrophic lateral sclerosis (ALS), and healthy controls (HC), using a multiplexed fluorescent bead-based immunoassay system. RESULTS: The induced protein (IP)10 level in the cells in both the MADSAM and MMN groups was markedly increased in comparison with the typical CIDP, ALS and HC groups. The other cytokines, including granulocyte colony-stimulating factor,vascular endothelial growth factor (VEGF) and interleukin-7, were also significantly upregulated in the MADSAM group. The increase of IP-10 produced by PnMECs was correlated with the presence of conduction block in both the MADSAM and MMN groups. CONCLUSION: The autocrine secretion of IP-10 induced by patient sera in PnMECs was markedly upregulated in both the MADSAM and MMN groups. The overproduction of IP-10 by PnMECs leads to the focal breakdown of the BNB and may help to mediate the transfer of pathogenic T cells across the BNB, thereby resulting in the appearance of conduction block in electrophysiological studies of patients with MADSAM and MMN.

Fingolimod promotes blood-nerve barrier properties in vitro.

Objective: The main effect of fingolimod is thought to be functional antagonism of lymphocytic S1P1 receptors and the prevention of lymphocyte egress from lymphoid tissues, thereby reducing lymphocyte infiltration into the nervous system. However, a growing number of reports suggest that fingolimod also has a direct effect on several cell types in the nervous system. Although we previously reported that fingolimod enhances blood-brain barrier (BBB) functions, there have been no investigations regarding the blood-nerve barrier (BNB). In this study, we examine how fingolimod affects the BNB. Methods: An immortalized human peripheral nerve microvascular endothelial cell line (HPnMEC) was used to evaluate BNB barrier properties. We examined tight junction proteins and barrier functions of HPnMECs in conditioned medium with or without fingolimod-phosphate and blood sera from patients with typical chronic inflammatory demyelinating polyneuropathy (CIDP). Results: Incubation with fingolimod-phosphate increased levels of claudin-5 mRNA and protein as well as TEER values in HPnMECs. Conversely, typical CIDP sera decreased claudin-5 mRNA/protein levels and TEER values in HPnMECs; however, pretreatment with fingolimod-phosphate inhibited the effects of the typical CIDP sera. Conclusions: Fingolimod-phosphate directly modifies the BNB and enhances barrier properties. This mechanism may be a viable therapeutic target for CIDP, and fingolimod may be useful in patients with typical CIDP who have severe barrier disruption.

Relapsing/remitting type 1 diabetes.

AIMS/HYPOTHESIS: Type 1 diabetes is believed to be an autoimmune disease associated with irreversible loss of insulin secretory function that follows a chronic progressive course. However, it has been speculated that relapsing/remitting disease progression may occur in type 1 diabetes. METHODS: We report the case of an 18-year-old girl with Graves' disease, chronic inflammatory demyelinating polyneuropathy (CIDP) and multiple islet autoantibodies, presenting with relapsing/remitting hyperglycaemia. Peripheral blood mononuclear cells were analysed for islet autoimmunity. RESULTS: There were two instances of hyperglycaemia relapse during CIDP flare-ups that required insulin therapy and remitted after i.v. immunoglobulin (IVIG) therapy improving neurological symptoms. A diagnosis of type 1 diabetes was assigned on the basis of insulin need, HbA1c and islet autoantibodies. Insulin requirements disappeared following IVIG treatment and peaked during CIDP flare-ups. Pro- and anti-inflammatory cytokine responses were noted against islet autoantigens. CONCLUSIONS/INTERPRETATION: We provide clinical evidence of relapsing/remitting type 1 diabetes associated with IVIG treatment and the regulation of islet autoimmunity. Despite sufficient residual beta cell mass, individuals can experience episodes of impaired glycaemia control. This disconnect between beta cell mass and function highlighted by our case may have implications for the use of beta cell function as the primary endpoint for immune intervention trials aiming to protect beta cell mass rather than function. Immune modulation may restore beta cell function and glycaemic control.

Fibronectin connecting segment-1 peptide inhibits pathogenic leukocyte trafficking and inflammatory demyelination in experimental models of chronic inflammatory demyelinating polyradiculoneuropathy.

The molecular determinants of pathogenic leukocyte migration across the blood-nerve barrier (BNB) in chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) are unknown. Specific disease modifying therapies for CIDP are also lacking. Fibronectin connecting segment-1 (FNCS1), an alternatively spliced fibronectin variant expressed by microvascular endothelial cells at sites of inflammation in vitro and in situ, is a counterligand for leukocyte α4 integrin (also known as CD49d) implicated in pathogenic leukocyte trafficking in multiple sclerosis and inflammatory bowel disease. We sought to determine the role of FNCS1 in CIDP patient leukocyte trafficking across the BNB in vitro and in severe chronic demyelinating neuritis in vivo using a representative spontaneous murine CIDP model. Peripheral blood mononuclear leukocytes from 7 untreated CIDP patients were independently infused into a cytokine-treated, flow-dependent in vitro BNB model system. Time-lapse digital video microscopy was performed to visualize and quantify leukocyte trafficking, comparing FNCS1 peptide blockade to relevant controls. Fifty 24-week old female B7-2 deficient non-obese diabetic mice with spontaneous autoimmune peripheral polyneuropathy (SAPP) were treated daily with 2mg/kg FNCS1 peptide for 5days via intraperitoneal injection with appropriate controls. Neurobehavioral measures of disease severity, motor nerve electrophysiology assessments and histopathological quantification of inflammation and morphometric assessment of demyelination were performed to determine in vivo efficacy. The biological relevance of FNCS1 and CD49d in CIDP was evaluated by immunohistochemical detection in affected patient sural nerve biopsies. 25µM FNCS1 peptide maximally inhibited CIDP leukocyte trafficking at the human BNB in vitro. FNCS1 peptide treatment resulted in significant improvements in disease severity, motor electrophysiological parameters of demyelination and histological measures of inflammatory demyelination. Microvessels demonstrating FNCS1 expression and CD49d+ leukocytes were seen within the endoneurium of patient nerve biopsies. Taken together, these results imply a role for FNCS1 in pathogenic leukocyte trafficking in CIDP, providing a potential target for therapeutic modulation.

Monoclonal gammopathy of undeterminated significance and endoneurial IgG deposition: A case report.

BACKGROUND: Monoclonal gammopathy of undeterminated significance is the most common form of plasma cell dyscrasia, usually considered as benign. In rare cases it may have a malignant course, sometimes limited to an organ such as peripheral nerves. METHODS: We describe clinical, electrophysiological and pathological findings in a patient presenting a immunoglobulin G (IgG) paraproteinemic polyneuropathy clinically mimicking a chronic inflammatory demyelinating polyneuropathy. RESULTS: Immuno-electron microscopy (immune-EM) demonstrated that the widenings of the myelin lamellae resulted from the infiltration of IgG between a significant number of myelin lamellae (with absence of inflammatory cells in the epineurium, endoneurium, and perineurium, and the lack signs of vasculitis). This patient was finally treated successfully with lenalidomide then mycophenolate mofetil. CONCLUSIONS: In polyneuropathies associated to a monoclonal gammopathy, a nerve biopsy may clinch the diagnosis. Immuno-EM may be required to determine the role of the pathological immunoglobulin in the destruction of the peripheral nerve parenchyma. Diagnosis of such a direct involvement of peripheral nerve can endorse more aggressive treatment of real efficiency.

NADPH oxidase 2 (NOX2) enzyme activation in patients with chronic inflammatory demyelinating polyneuropathy.

BACKGROUND AND PURPOSE: Chronic inflammatory demyelinating polyneuropathy (CIDP) is an acquired immunomediated condition affecting the peripheral nervous system where probably macrophages are the primary effector cells for demyelination. Reactive oxygen species (ROS), catalyzed by the NOX family of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase enzymes, can induce peroxidation and are potentially injurious to myelin. Our aim was to assess the activity of NOX2, an isoform of NOX, in a series of CIDP patients and to analyze the effect of intravenous immunoglobulin (IVIg) on NOX2. METHODS: Thirty CIDP patients treated with IVIg and 30 control subjects were enrolled. To evaluate NOX2 activity, neutrophil and monocyte oxidative burst was measured directly in fresh whole blood using the Phagoburst™ assay, a fluorescence-activated cell sorting method. The mean fluorescence intensity, emitted in response to different stimuli, leads to the production of ROS and corresponds to the percentage of oxidizing cells and their enzymatic activity. RESULTS: Mean fluorescence intensity values for granulocyte and monocyte burst in patients (mean 633.3, SD 191; mean 111.8, SD 28.5) were different from those measured in healthy controls (granulocytes, mean 436.6, SD 137.0, P = 0.0003; monocytes, mean 78.2, SD 17.3, P = 0.000001). Moreover, IVIg administration increased both granulocyte (P = 0.005) and monocyte (P = 0.0009) burst. CONCLUSION: Our findings demonstrate that oxidative burst is significantly increased in CIDP patients and that treatment with IVIg enhances oxidative values, thus representing a possible IVIg therapeutic effect linked to a regulatory effect of ROS. Based on this, the development of treatments targeting the specific activation of NOX may be beneficial in autoimmune disorders.

Frequent laboratory abnormalities in CIDP patients.

INTRODUCTION: The role of screening laboratory tests in chronic inflammatory demyelinating polyneuropathy (CIDP) is currently unknown. The objectives of this study are to explore common laboratory test abnormalities in CIDP patients. METHODS: CIDP subjects attending the Neuromuscular Clinic between 01/2013 and 12/2014 were evaluated. Demographic data, clinical history, physical examination, and laboratory test results were extracted from their charts. RESULTS: Seventy-nine charts were reviewed. Mean age was 61 ± 11 years. Most (84%) CIDP patients had laboratory test abnormalities; the most frequent were paraproteinemia (29%) and elevated HbA1C (28%) and creatine kinase (27%). Additional abnormalities included anemia in 19%, and elevated anti-neutrophil cytoplasmic antibody, erythrocyte sedimentation rate, and urate in 17%, elevated antinuclear antibodies, rheumatoid factor, and thyroid-stimulating hormone in 11%, and abnormal C3 in 10%. CONCLUSIONS: Laboratory test abnormalities were found in most CIDP patients. The most common were paraproteinemia, higher than expected frequency of diabetes, and unexpected CK elevation. Additional abnormalities included anemia, high urate levels, and common biomarkers for vasculitic neuropathies. Muscle Nerve 53: 862-865, 2016.

The frequencies of Killer immunoglobulin-like receptors and their HLA ligands in chronic inflammatory demyelinating polyradiculoneuropathy are similar to those in Guillian Barre syndrome but differ from those of controls, suggesting a role for NK cells in pathogenesis.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is an acquired inflammatory neuropathy, which has similar clinical and pathological features to Guillain-Barré Syndrome (GBS), but differs in time course. We investigated the frequency of genes encoding Killer immunoglobulin-like receptors and their HLA ligands in subjects with CIDP, in subjects with GBS and in healthy controls. There were no differences in KIR gene frequency among the 3 groups. The gene frequencies for HLA-B Bw4-I were significantly greater in CIDP than HC, but did not differ from GBS. The frequency of the combination of 3DL1/HLA-B Bw4I was greater in CIDP than HC, but did not differ from that of GBS. These data raise the possibility of NK cell function being an important factor in the pathogenesis of CIDP.

New insights into the management of chronic inflammatory demyelinating polyradiculoneuropathy.

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) and its variants can be challenging to diagnose and treat. A combination of clinical, electrophysiological and laboratory features is often required to reach a diagnosis. New data are emerging about potential biomarkers and factors that may indicate treatment needs in individual patients. High-quality evidence exists for the efficacy of intravenous immunoglobulin (IVIG) in the treatment of CIDP, including quality of life (QoL) benefits. Besides pharmacological treatment, psychological factors must also be addressed to improve patients' QoL. Home-based IVIG infusion therapy is currently a well-established approach in some countries. A 6-month pilot study conducted in Ontario, Canada, provided proof of safety and patient acceptance of home-based IVIG therapy, although some logistical issues emerged.

An autopsy case involving a 12-year history of amyotrophic lateral sclerosis with CIDP-like polyneuropathy.

Demyelinating polyneuropathy associated with amyotrophic lateral sclerosis (ALS) is quite rare. We herein present the case of a woman patient with a 12-year history of chronic inflammatory demyelinating polyneuropathy (CIDP)-like polyneuropathy who later developed bulbar palsy and respiratory failure. The autopsy findings revealed neuronal loss in the anterior horn and primary motor cortex with degeneration of the corticospinal tracts. Diffuse phosphorylated TAR DNA-binding protein of 43 kDa inclusions were observed in the anterior horn and cerebral cortices, including the temporal lobe. The final diagnosis was ALS with CIDP-like polyneuropathy. Compared with other reports of ALS with CIDP-like polyneuropathy, the present patient was younger and followed a relatively long clinical course, with no upper motor neuron signs.

[Pathogenesis of chronic inflammatory demyelinating polyneuropathy].

Chronic inflammatory demyelinating polyneuropathy (CIDP) is considered to be a demyelinating autoimmune disorder in the peripheral nervous system. Concerning cellular immune response, activity of IFN-gamma producing Th1 and IL-17 producing Th17 cells might be accelerated in patients with CIDP, while regulatory function of CD4+ CD25(high) Foxp3+ regulatory T cells might be diminished. Humoral immune responses against several myelin components such as myelin protein zero and gangliosides such as GM1 might be also induced in a part of patients with CIDP. Besides, growing body of evidences suggest that immune response against several molecules expressed in the noncompact myelin might be involved in the pathogenesis of CIDP.

Immunoglobulin G level variations in treated chronic inflammatory demyelinating polyneuropathy: clues for future treatment regimens?

Intravenous immunoglobulins (IVIg) are effective for treating chronic inflammatory demyelinating polyneuropathy (CIDP), although treatment needs are variable and need to be individualized. Dose and frequency requirements are not currently predictable in advance. In Guillain-Barré syndrome, IVIg interpatient pharmacokinetic variations have been demonstrated in relation to clinical outcome. We studied 15 patients with CIDP following two routine courses of IVIg. IgG levels were assessed pretreatment and 14 days post-treatment. Best clinical response (BCR) was ascertained in each case, predefined, according to individual patients' circumstances, on the 10 m walk, or MRC sum score, or Jamar grip dynamometry. Correlations between IgG level variations, doses administered, weight, body mass index, BCR and infusion interval were determined. Postinfusion rise in IgG levels were correlated in individual patients (p = 0.005), but interpatient variability was high. No correlations were ascertained between IgG level variation and weight, body mass index, BCR, total dose of IVIg administered, or dose of IVIg administered per kilogram per week. There were significant correlations between total dose administered and post-infusion IgG level at 14 days (p = 0.004) and between infusion interval and mean rise in IgG level (p = 0.001) These findings suggest significant variability in IgG metabolism between patients, unrelated to minimal effective dose administered, weight, body mass index or degree of functional improvement. Required frequency of IVIg infusions may, however, importantly relate to patient-specific post-infusion rise in IgG levels hence possibly explaining inter-patient differences in treatment frequency needs. IgG level monitoring may be helpful in establishing optimum treatment regimens in individual cases.

Different profiles of onion bulb in CIDP and CMT1A in relation to extracellular matrix.

Hypertrophic neuropathy is usually intractable, and chronic inflammatory demyelinating polyneuropathy (CIDP) and Charcot-Marie-Tooth disease Type 1A (CMT1A) are the representative disorders. The two disorders are sometimes confused both clinically and pathologically. The aim of this study was to clarify the differences in the pathology of large onion bulbs, focusing on the extracellular matrix (ECM) proteins. Nine patients with CIDP and 14 with CMT1A were included. The opened interspaces in OB were frequently shown in CMT1A patients. In CIDP, interspaces of OB packed with collagen fibers were prominent. The mean ratio of opened OB was significantly increased in CMT1A (37.9%) compared to CIDP patients (10.6%) (p = 0.003). Among the ECM examined, tenascin-C (TNC) showed a distinct difference in the pattern of immunoreactivity of OB. The mean ratio of OB showing TNC immunoreactivity was significantly larger in CIDP (29.7%, p = 0.005) than in CMT1A (5.0%). TNC immunoreactivity was confined to the area around myelin sheaths in CMT1A. The increased deposition of collagen fibers in CIDP suggests the activity of nerve regeneration. TNC expression in Schwann cell lamellae comprising OB may also suggest the activity of regeneration. Schwann cell phenotypes in CIDP may be different from CMT1A regarding the production of ECM proteins.