Peripheral Demyelinating Diseases Research Articles

Polycaprolactone/graphene oxide/acellular matrix nanofibrous scaffolds with antioxidant and promyelinating features for the treatment of peripheral demyelinating diseases

Peripheral demyelinating diseases entail damage to axons and Schwann cells in the peripheral nervous system. Because of poor prognosis and lack of a cure, this group of diseases has a global impact. The primary underlying cause of these diseases involves the inability of Schwann cells to remyelinate the damaged insulating myelin around axons, resulting in neuronal death over time. In the past decade, extensive research has been directed in the direction of Schwann cells focusing on their physiological and neuroprotective effects on the neurons in the peripheral nervous system. One cause of dysregulation in the remyelinating function of Schwann cells has been associated with oxidative stress. Tissue-engineered biodegradable scaffolds that can stimulate remyelination response in Schwann cells have been proposed as a potential treatment strategy for peripheral demyelinating diseases. However, strategies developed to date primarily focussed on either remyelination or oxidative stress in isolation. Here, we have developed a multifunctional nanofibrous scaffold with material and biochemical cues to tackle both remyelination and oxidative stress in one matrix. We developed a nanofibrous scaffold using polycaprolactone (PCL) as a foundation loaded with antioxidant graphene oxide (GO) and coated this bioscaffold with Schwann cell acellular matrix. In vitro studies revealed both antioxidant and remyelination properties of the developed bioscaffold. Based on the results, the developed multifunctional bioscaffold approach can be a promising biomaterial approach for treating demyelinating diseases.Graphical

Vitamin D Level in Children with Acute and Relapsing Demyelinating Disorders of the Nervous System

Background Vitamin D has recently gained increased attention owing to its immunomodulatory role. Epidemiological evidence demonstrates that deficiency of Vitamin D is a relevant risk for acute acquired immune-mediated inflammatory demyelinating diseases in childhood, such as Multiple sclerosis (MS). Exact mechanism remains widely unexplored. Aim to measure the serum level vitamin D-25(OH) in pediatric patients diagnosed with acquired central and peripheral demyelinating diseases, and to compare these to levels found in healthy age and gender matched controls. Patients and Methods Twenty children (patients’ group) diagnosed with acute demyelinating diseases (Acute Disseminated Encephalomyelitis (ADEM, n = 7), Acute Necrotizing Encephalopathy of Childhood (ANEC, n = 3), Autoimmune Encephalitis (AE, n = 3), Transverse Myelitis (TM, n = 3), Guillain-Barre syndrome (GBS, n = 4)) and 40 healthy age and gender matched children (control group), were enrolled in the study. All patients were subject to full history, examination and measurement of serum levels of 25 (OH) vitamin D3 in both cases and control group. Results The mean level of vitamin D in cases was 4.4 ± 11.14 ng/ml, and it was deficient in 75% of the cases and insufficient in 15% of cases. The mean vitamin d level in cases was significantly lower than that in controls (27.18 ± 7.8 ng/ml). Conclusion Serum levels of 25 (OH) Vitamin D3 in pediatric acute acquired demyelinating diseases of the nervous system are significantly lower than levels in healthy controls, raising a possibility that vitamin D deficiency may be a risk factor for the development of various autoimmune neurological diseases.

CXCL13 Level in Children with Acute and Relapsing Demyelinating Disorders of the Nervous system

Background The chemokine, C-X-C motif ligand 13 (CXCL13) plays an important role in B cell recruitment within the central nervous system (CNS). CXCL13 has been implicated as key regulatory factor in inflammatory CNS disorders including autoimmune CNS diseases. Aim of the Work To compare between the serum level of CXCL13 in patients diagnosed with acute central or peripheral demyelination and in healthy age and gender matched controls. Patients and Methods Twenty patients (patients’ group) diagnosed with acute demyelinating diseases (acute disseminated encephalomyelitis (ADEM; n = 7), acute necrotizing encephalopathy of childhood (ANEC; n = 3), autoimmune encephalitis (AE; n = 3), transverse myelitis (TM; n = 3), Guillain-Barré syndrome (GBS; n = 4) and 40 healthy age and gender matched children (control group), were enrolled in the study. All patients were subject to full history, examination and measurement of serum levels of CXCL13 in both cases and controls. Results Serum CXCL13 level status was significantly higher in cases compared to controls (p < 0.001). The mean serum CXCL13 level in cases was (341.75 ± 164.71 pg/ml) and in control was (51.5 ± 18.99 pg/ml). Conclusion Serum CXCL13 levels are significantly increased in pediatric patients with acute acquired central and peripheral demyelinating diseases of the nervous system.

A case study of combined central and peripheral demyelination with antibodies against paranodal protein neurofascin 186

We report the diagnostic process of a rare patient with a combined central and peripheral demyelinating disease with antibodies against paranodal protein neurofascin 186 (anti– NF186)—the patient presented with weakness in both lower limbs. The clinical process and evidence are similar to subacute combined degeneration. However, thoracic spinal MRI shows T1 equal signal, and T2 high signal lesions in thoracic vertebrae 5-7 mainly involve white matter. The Aquaporin 4 antibody of the central nervous system indicates the disease is of an optic neuromyelitis pedigree. The antibodies against paranodal protein neurofascin 186 indicate demyelinating peripheral nerve pathogenesis. The final diagnosis was a combined central and peripheral demyelinating disease based on the results of various examinations. The patient's condition improved after methylprednisolone therapy and intravenous immunoglobulin.

Acute Disseminated Encephalomyelitis Following Campylobacter jejuni Infection in a 12-Year-Old Girl

AbstractWe reported a case of acute disseminated encephalomyelitis (ADEM) in a 12-year-old girl shortly after developing fever and vomiting, and ultimately found to have Campylobacter jejuni by antigen detection and conventional stool culture. Campylobacter jejuni has been associated with peripheral demyelinating diseases including Guillain–Barre's syndrome, but it has not been previously implicated in central demyelination in children. The clinical description and review of the literature are included here.

Soluble dimeric prion protein ligand activates Adgrg6 receptor but does not rescue early signs of demyelination in PrP-deficient mice.

The adhesion G-protein coupled receptor Adgrg6 (formerly Gpr126) is instrumental in the development, maintenance and repair of peripheral nervous system myelin. The prion protein (PrP) is a potent activator of Adgrg6 and could be used as a potential therapeutic agent in treating peripheral demyelinating and dysmyelinating diseases. We designed a dimeric Fc-fusion protein comprising the myelinotrophic domain of PrP (FT2Fc), which activated Adgrg6 in vitro and exhibited favorable pharmacokinetic properties for in vivo treatment of peripheral neuropathies. While chronic FT2Fc treatment elicited specific transcriptomic changes in the sciatic nerves of PrP knockout mice, no amelioration of the early molecular signs demyelination was detected. Instead, RNA sequencing of sciatic nerves revealed downregulation of cytoskeletal and sarcomere genes, akin to the gene expression changes seen in myopathic skeletal muscle of PrP overexpressing mice. These results call for caution when devising myelinotrophic therapies based on PrP-derived Adgrg6 ligands. While our treatment approach was not successful, Adgrg6 remains an attractive therapeutic target to be addressed in other disease models or by using different biologically active Adgrg6 ligands.

The involvement of anti-neurofascin 155 antibodies in central and peripheral demyelinating diseases

The involvement of anti-neurofascin 155 antibodies in central and peripheral demyelinating diseases

Peripheral Demyelinating Diseases: From Biology to Translational Medicine.

Demyelinating diseases represent a spectrum of disorders that impose significant burden on global economy and society. Generally, the prognosis of these diseases is poor and there is no available cure. In recent decades, research has shed some light on the biology and physiology of Schwann cells and its neuroprotective effects in the peripheral nervous system (PNS). Insults to the PNS by various infectious agents, genetic predisposition and immune-related mechanisms jeopardize Schwann cell functions and cause demyelination. To date, there are no effective and reliable biomarkers for PNS-related diseases. Here, we aim to review the following: pathogenesis of various types of peripheral demyelinating diseases such as Guillain-Barre syndrome, Chronic Inflammatory Demyelinating Polyradiculoneuropathy, Anti-Myelin Associated Glycoprotein Neuropathy, POEMS syndrome, and Charcot-Marie-Tooth disease; emerging novel biomarkers for peripheral demyelinating diseases, and Schwann cell associated markers for demyelination.

A Simple Approach to Induce Experimental Autoimmune Neuritis in C57BL/6 Mice for Functional and Neuropathological Assessments

Experimental autoimmune neuritis (EAN) is a well-appreciated experimental model of autoimmune peripheral demyelinating diseases. EAN disease is induced by immunizing mice with neurogenic peptides to direct an inflammatory attack toward components of the peripheral nervous system (PNS). Recent advances have enabled the induction of EAN in the relatively resistant C57BL/6 mouse line using myelin protein zero (P0)106-125 or P0180-199 peptides delivered in adjuvant combined with the injection of pertussis toxin. The ability to induce EAN in the C57BL/6 strain allows for the use of the numerous genetic tools that exist on this mouse background, and thus allows the sophisticated study of disease pathogenesis and interrogation of the mechanistic action of novel therapeutics in combination with transgenic approaches. In this study, we demonstrate a simple approach to successfully induce EAN using the P0180-199 peptide in C57BL/6 mice. We also outline a protocol for the assessment of functional deficits that occur in this model, accompanied by an array of neuropathological features. Thus, this model is a powerful experimental model to study the pathogenesis of human peripheral demyelinating neuropathies, and to determine the efficacy of potential therapies that aim to promote myelin repair and protect against nerve damage in autoimmune neuritis.

A Brain-Derived Neurotrophic Factor-Based p75NTR Peptide Mimetic Ameliorates Experimental Autoimmune Neuritis Induced Axonal Pathology and Demyelination.

Axonal damage and demyelination are major determinants of disability in patients with peripheral demyelinating neuropathies. The neurotrophin family of growth factors are essential for the normal development and myelination of the peripheral nervous system (PNS), and as such are potential therapeutic candidates for ameliorating axonal and myelin damage. In particular, BDNF promotes peripheral nerve myelination via p75 neurotrophin receptor (p75NTR) receptors. Here, we investigated the therapeutic efficacy of a small structural mimetic of the region of BDNF that binds to p75NTR (cyclo-dPAKKR) in experimental autoimmune neuritis (EAN), an established animal model of peripheral demyelinating neuropathy. Examination of rodents induced with EAN revealed that p75NTR is abundantly expressed in affected peripheral nerves. We found that systemic administration of cyclo-dPAKKR ameliorates EAN disease severity and accelerates recovery. Animals treated with cyclo-dPAKKR displayed significantly better motor performance compared to control animals. Histological assessment revealed that cyclo-dPAKKR administration limits the extent of inflammatory demyelination and axonal damage, and protects against the disruption of nodal architecture in affected peripheral nerves. In contrast, a structural control peptide of cyclo-dPAKKR exerted no influence. Moreover, all the beneficial effects of cyclo-dPAKKR in EAN are abrogated in p75NTR heterozygous mice, strongly suggesting a p75NTR-dependent effect. Taken together, our data demonstrate that cyclo-dPAKKR ameliorates functional and pathological defects of EAN in a p75NTR-dependant manner, suggesting that p75NTR is a therapeutic target to consider for future treatment of peripheral demyelinating diseases and targeting of p75NTR is a strategy worthy of further investigation.

Stimulation-induced Ca(2+) influx at nodes of Ranvier in mouse peripheral motor axons.

In peripheral myelinated axons of mammalian spinal motor neurons, Ca(2+) influx was thought to occur only in pathological conditions such as ischaemia. Using Ca(2+) imaging in mouse large motor axons, we find that physiological stimulation with trains of action potentials transiently elevates axoplasmic [C(2+)] around nodes of Ranvier. These stimulation-induced [Ca(2+)] elevations require Ca(2+) influx, and are partially reduced by blocking T-type Ca(2+) channels (e.g. mibefradil) and by blocking the Na(+)/Ca(2+) exchanger (NCX), suggesting an important contribution of Ca(2+) influx via reverse-mode NCX activity. Acute disruption of paranodal myelin dramatically increases stimulation-induced [Ca(2+)] elevations around nodes by allowing activation of sub-myelin L-type (nimodipine-sensitive) Ca(2+) channels. The Ca(2+) that enters myelinated motor axons during normal activity is likely to contribute to several signalling pathways; the larger Ca(2+) influx that occurs following demyelination may contribute to the axonal degeneration that occurs in peripheral demyelinating diseases. Activity-dependent Ca(2+) signalling is well established for somata and terminals of mammalian spinal motor neurons, but not for their axons. Imaging of an intra-axonally injected fluorescent [Ca(2+)] indicator revealed that during repetitive action potential stimulation, [Ca(2+)] elevations localized to nodal regions occurred in mouse motor axons from ventral roots, phrenic nerve and intramuscular branches. These [Ca(2+)] elevations (∼ 0.1 μm with stimulation at 50 Hz, 10 s) were blocked by removal of Ca(2+) from the extracellular solution. Effects of pharmacological blockers indicated contributions from both T-type Ca(2+) channels and reverse mode Na(+)/Ca(2+) exchange (NCX). Acute disruption of paranodal myelin (by stretch or lysophosphatidylcholine) increased the stimulation-induced [Ca(2+)] elevations, which now included a prominent contribution from L-type Ca(2+) channels. These results suggest that the peri-nodal axolemma of motor axons includes multiple pathways for stimulation-induced Ca(2+) influx, some active in normally-myelinated axons (T-type channels, NCX), others active only when exposed by myelin disruption (L-type channels). The modest axoplasmic peri-nodal [Ca(2+)] elevations measured in intact motor axons might mediate local responses to axonal activation. The larger [Ca(2+) ] elevations measured after myelin disruption might, over time, contribute to the axonal degeneration observed in peripheral demyelinating neuropathies.

Paroxysmal nocturnal hemoglobinuria (PNH) and primary p.Cys89Tyr mutation in CD59: Differences and similarities.

CD59 encodes a 77 amino acid glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein that inhibits the final step of membrane attack complex (MAC) formation. CD59 deficiency is a common finding in adult patients with paroxysmal nocturnal hemoglobinuria (PNH). In this condition, there is a clonal expansion of hematopoietic stem cells that have acquired a mutation in the PIGA gene (phosphatidylinositol glycan anchor biosynthesis, class A). PIGA encodes a GPI biosynthesis protein, phosphatidylinositol N-acetylglucosaminyltransferase subunit A, and erythrocytes deficient in GPI-anchored membrane proteins, including CD59, undergo complement-mediated hemolysis. We have recently described a primary homozygous Cys89Tyr CD59 deficiency in humans that resulted in the amino acid substitution p.Cys89Tyr with resulting failure of proper localization of the CD59 protein to the cell surface. The Cys89Tyr mutation in CD59 was clinically manifested in infancy, and associated with chronic hemolysis and relapsing peripheral demyelinating disease resembling recurrent Guillain-Barré syndrome (GBS) or chronic inflammatory demyelinating polyneuropathy (CIDP). In this review we describe differences and similarities in the pathogenesis and clinical manifestations of PNH and primary CD59 Cys89Tyr mutation with the aim of tracking the contribution of CD59 deficiency to the pathophysiology and perhaps deepening our understanding of both diseases.

Hydrogen sulfide controls peripheral nerve degeneration and regeneration: a novel therapeutic strategy for peripheral demyelinating disorders or nerve degenerative diseases.

After peripheral nerve injury, the process of Wallerian degeneration is initiated in the distal stump of injured nerves. Wallerian degeneration in peripheral nerves involves axonal degeneration and degradation of the myelin sheath in Schwann cells. This provides the necessary conditions for axonal regeneration and remyelination. After nerve injury, macrophages are also recruited to the distal nerve stump and, together with Schwann cells, play a role in the clearance of myelin debris. Thus, a series of processes help to promote peripheral nerve regeneration, which includes axonal regeneration and remyelination. This is in contrast to injuries within the adult central nervous system, in which successful regeneration encounters several significant barriers: myelin-associated inhibition (Neuman et al., 2002), diminished axonal growth capacity (Ruff et al., 2008) and glial scarring (Yiu and He, 2006). Because the successful regeneration of injured peripheral nerves relies on a harmonious degenerating process, it is essential to identify a molecular mechanism that regulates axonal degeneration or myelin fragmentation during Wallerian degeneration to foster the conditions allowing efficient peripheral nerve regeneration. We have recently shown that hydrogen sulfide (H2S) is important for axonal degradation and demyelination. We focus here on the effects of H2S on axonal degradation and on understanding the underlying mechanisms of H2S-associated demyelination, dedifferentiation and proliferation in Schwann cells during Wallerian degeneration. In addition, we discuss a novel strategy for nerve regeneration in the injured perip heral nerve or peripheral neuropathy.

P.6.9 Childhood relapsing immune-mediated polyneuropathy and hemolysis is associated with CD59 deficiency

The objective of the present study was to elucidate the molecular basis of a new clinical entity of childhood familial immune mediated relapsing polyneuropathy associated with chronic Coombs-negative hemolysis. Since infancy these children had recurrent episodes of weakness and hemolysis with partial improvement following immune modulating therapy. One child died at the age of 3.5years while the others demonstrated severe lower limb paralysis. A founder mutation was searched for using homozygosity mapping followed by exome sequencing in 5 infants of North-African Jewish origin from 4 unrelated families. The expression of CD59, CD55, and CD14 was examined in blood cells by flow cytometry followed by Western blot of the CD59 protein. Homozygous missense mutation, p.Cys89Tyr in CD59, was identified in all patients. The mutation segregated with the disease in the families and had a carrier rate of 1:66 among Jewish subjects of North-African origin. The mutated protein was present in the patients' cells in reduced amounts and was undetectable on the membrane surface. CD59 deficiency is a common finding in RBCs and WBCs in patients with chronic hemolysis suffering from paroxysmal nocturnal hemoglobinuria in which the acquired mutation in the PIGA gene leads to membrane loss of glycosylphosphatidylinositol-anchored membrane proteins, including CD59. Based on the results of the present study, we suggest that the Cys89Tyr mutation in CD59 is associated with a failure of proper localization of the CD59 protein in the cell surface and decreased complement inhibition. This mutation is manifested clinically in infancy by relapsing peripheral demyelinating disease and chronic hemolysis.

Mechanism of experimental autoimmune neuritis in Lewis rats: the dual role of macrophages.

Human peripheral demyelinating diseases, such as Guillain-Barré syndrome (GBS), are characterized by inflammation and demyelination in the peripheral nervous system. Similarities in the pathology between GBS and the animal model of experimental autoimmune neuritis (EAN) indicate that autoimmune responses are involved in both diseases. This article summarizes the general aspects of the EAN model in Lewis rats and discusses the potential role of macrophages in the progression of EAN. A better understanding of macrophages may help to design alternative therapeutic strategies for organ-specific autoimmune diseases, including GBS.

A small peptide mimetic of brain‐derived neurotrophic factor promotes peripheral myelination

The expression of the neurotrophins and their receptors is essential for peripheral nervous system development and myelination. We have previously demonstrated that brain-derived neurotrophic factor (BDNF) exerts contrasting influences upon Schwann cell myelination in vitro - promoting myelination via neuronally expressed p75NTR, but inhibiting myelination via neuronally expressed TrkB. We have generated a small peptide called cyclo-dPAKKR that structurally mimics the region of BDNF that binds p75NTR. Here, we have investigated whether utilizing cyclo-dPAKKR to selectively target p75NTR is an approach that could exert a unified promyelinating response. Like BDNF, cyclo-dPAKKR promoted myelination of nerve growth factor-dependent neurons in vitro, an effect dependent on the neuronal expression of p75NTR. Importantly, cyclo-dPAKKR also significantly promoted the myelination of tropomyosin-related kinase receptor B-expressing neurons in vitro, whereas BDNF exerted a significant inhibitory effect. This indicated that while BDNF exerted a contrasting influence upon the myelination of distinct subsets of dorsal root ganglion (DRG) neurons in vitro, cyclo-dPAKKR uniformly promoted their myelination. Local injection of cyclo-dPAKKR adjacent to the developing sciatic nerve in vivo significantly enhanced myelin protein expression and significantly increased the number of myelinated axons. These results demonstrate that cyclo-dPAKKR promotes peripheral myelination in vitro and in vivo, suggesting it is a strategy worthy of further investigation for the treatment of peripheral demyelinating diseases.

CD59 deficiency is associated with chronic hemolysis and childhood relapsing immune-mediated polyneuropathy

AbstractCD59 deficiency is a common finding in RBCs and WBCs in patients with chronic hemolysis suffering from paroxysmal nocturnal hemoglobinuria in which the acquired mutation in the PIGA gene leads to membrane loss of glycosylphosphatidylinositol-anchored membrane proteins, including CD59. The objective of the present study was to elucidate the molecular basis of childhood familial chronic Coombs-negative hemolysis and relapsing polyneuropathy presenting as chronic inflammatory demyelinating polyradiculoneuropathy in infants of North-African Jewish origin from 4 unrelated families. A founder mutation was searched for using homozygosity mapping followed by exome sequencing. The expression of CD59, CD55, and CD14 was examined in blood cells by flow cytometry followed by Western blot of the CD59 protein. A homozygous missense mutation, p.Cys89Tyr in CD59, was identified in all patients. The mutation segregated with the disease in the families and had a carrier rate of 1:66 among Jewish subjects of North-African origin. The mutated protein was present in the patients' cells in reduced amounts and was undetectable on the membrane surface. Based on the results of the present study, we conclude that the Cys89Tyr mutation in CD59 is associated with a failure of proper localization of the CD59 protein in the cell surface. This mutation is manifested clinically in infancy by chronic hemolysis and relapsing peripheral demyelinating disease.

CD59 Deficiency Is Associated with Chronic Hemolysis and Childhood Chronic Immune Mediated Neuropathy

Abstract 3187CD59 deficiency is a common finding in red and white blood cells in patients with chronic hemolysis suffering from paroxysmal nocturnal hemoglobinuria (PNH) where acquired mutation in the PIGA gene leads to membrane loss of GPI-anchored membrane proteins, including CD59. The current study objective was the elucidation of the molecular basis of childhood familial chronic Coombs' negative hemolysis and relapsing polyneuropathy, mimicking chronic inflammatory demyelinating polyradiculoneuropathy in infants of North-African Jewish origin from four unrelated families. A founder mutation was searched using homozygosity mapping followed by exome sequencing. The expression of CD59, CD55 and CD14 was examined in blood cells by flow cytometry followed by western blot of the CD59 protein. A homozygous missense mutation in CD59, was identified in all the patients. The mutation segregated with the disease in the families and had a carrier rate of 1:66 among Jews of North-African origin. The mutated protein was present in the patients' cells in normal amount but was undetectable on the membrane surface.Conclusion: This is the first clinical and molecular characterization of a novel clinical syndrome. CD59 mutation is associated with a failure of proper localization of CD59 protein in the cell surface. This is clinically manifested in infancy by chronic hemolysis and relapsing peripheral demyelinating disease. Disclosures:No relevant conflicts of interest to declare.

Peripheral Mechanisms of Neuropathic Pain — Involvement of Lysophosphatidic Acid Receptor-Mediated Demyelination

Recent advances in pain research provide a clear picture for the molecular mechanisms of acute pain; substantial information concerning plasticity that occurs during neuropathic pain has also become available. The peripheral mechanisms responsible for neuropathic pain are found in the altered gene/protein expression of primary sensory neurons. With damage to peripheral sensory fibers, a variety of changes in pain-related gene expression take place in dorsal root ganglion neurons. These changes, or plasticity, might underlie unique neuropathic pain-specific phenotype modifications – decreased unmyelinated-fiber functions, but increased myelinated A-fiber functions. Another characteristic change is observed in allodynia, the functional change of tactile to nociceptive perception. Throughout a series of studies, using novel nociceptive tests to characterize sensory-fiber or pain modality-specific nociceptive behaviors, it was demonstrated that communication between innocuous and noxious sensory fibers might play a role in allodynia mechanisms. Because neuropathic pain in peripheral and central demyelinating diseases develops as a result of aberrant myelination in experimental animals, demyelination seems to be a key mechanism of plasticity in neuropathic pain. More recently, we discovered that lysophosphatidic acid receptor activation initiates neuropathic pain, as well as possible peripheral mechanims of demyelination after nerve injury. These results lead to further hypotheses of physical communication between innocuous Aβ- and noxious C- or Aδ-fibers to influence the molecular mechanisms of allodynia.

Trace elements in cerebrospinal fluid and blood from patients with a rare progressive central and peripheral demyelinating disease

A hereditary neurological disease in a family in Norway has been reported recently. The disease, which we refer to as Skogholt's disease, is a demyelinating disorder of both the central and the peripheral nervous system with adult onset. We investigated whether changes in trace element concentrations could play a role in Skogholt's disease. Using high resolution inductively coupled plasma mass spectrometry, we determined 31 elements in cerebrospinal fluid (CSF), blood plasma and whole blood from these patients, multiple sclerosis patients and a control group. More than threefold increased levels of Cu and Fe, and a twofold increase in Zn were found in the CSF of Skogholt patients compared to controls. Several other significant differences in trace element levels were also found. The increased levels of Cu and Fe in CSF may indicate an active role of these metals in the pathogenesis of Skogholt's disease. Apparently, these metal ions are transferred into the CSF through their protein chelation, as raised protein levels were also seen. We suggest that redistribution of metals from transport proteins into vulnerable sites in the central (and peripheral) nervous system may initiate critical lesions.