CSF oligoclonal band status informs prognosis in multiple sclerosis: a case control study of 100 patients

OBJECTIVE

Oligoclonal band (OCB) negative multiple sclerosis (MS) is well recognised but uncommon, studied in only a few usually small case series. These reached differing conclusions on whether its clinical features or course differ from OCB positive disease. The study hypothesis was that a definitive study would not only be of clinical and prognostic value but also potentially offer information about the possible role of CSF oligoclonal immunoglobulins in MS disease processes.

METHODS

A collaborative cohort of well documented patients in southwest England and south Wales was used to identify and analyse a large group of patients with OCB negative MS and make comparisons with age and sex matched OCB positive controls.

RESULTS

An approximate minimum 3% of patients with MS were OCB negative. They were significantly more likely to exhibit neurological or systemic clinical features atypical of MS (headaches, neuropsychiatric features and skin changes). Non-specific MRI, blood and (other) CSF abnormalities were also more common, emphasising the need for continued diagnostic vigilance, although the incautious application of McDonald diagnostic criteria in OCB negative cases renders categorisation as "definite" MS more likely. Studying the uniformly assessed Cardiff group (69 patients), we found the prognosis for neurological disability was significantly better for OCB negative cases. The age adjusted hazard ratio for OCB negative and OCB positive subjects to reach Disability Scale Status (DSS) 4 and DSS 6 was, respectively, 0.60 (95% CI 0.39 to 0.93; p = 0.02) and 0.51 (95% CI 0.27 to 0.94; p = 0.03).

CONCLUSION

There are clear clinical differences between OCB negative and OCB positive MS, in particular a better prognosis for disability. This is consistent with a secondary but nonetheless contributory role in disease process for intrathecally synthesised immunoglobulins.

Neurosarcoidosis: a study of 30 new cases

METHODS

The frequency, nature, relationship to systemic features, value of investigation findings and outcomes for a cohort of patients with neurosarcoidosis (NS) were studied by performing a retrospective survey of case records from nine District General or Regional Centre hospitals in south-west England and south Wales over a 12-year period (1990-2002). Thirty patients (29 Caucasians) were included--16 (53%) males and 14 (47%) females, including 13 with histological confirmation of CNS disease, making this one of the largest series of biopsy-confirmed NS; the remaining cases had "Probable" NS according to the Zajicek criteria. The male preponderance is of interest particularly considering the female predominance of systemic sarcoidosis.

RESULTS

The indicative prevalence of NS in this geographical area was estimated at one per 100,000, given an approximate population of 3 million. The most frequent features were headaches, visual failure, ataxia and vomiting. Cranial neuropathy occurred in 80% of patients, and as a presenting feature in 50%--though facial nerve involvement was seen in only 23%, and in none of those with definite disease. Unsurprisingly, no diagnostic clinical patterns emerged overall when only definite cases were analysed, but within our definite group of patients, meningeal and/or parenchymal lesion enhancement was observed in all but one case, while distinction from multiple sclerosis might also be aided by the observation that in all NS cerebrospinal fluid (CSF) samples with positive oligoclonal bands (27%), banding was accompanied by elevations of CSF protein.

CONCLUSION

From a prognostic perspective, the reported association of seizures in NS with a poor long-term outcome was not supported, while the suggestion that myelopathy also predicts an adverse prognosis was confirmed.

Human mesenchymal stem cell culture for neural transplantation

Mesenchymal stem cells (MSCs) have the potential to play a role in autologous repair of central nervous system injury or disease, circumventing both the complications associated with immune rejection of allogenic cells, and many of the ethical concerns associated with embryonic stem cell use. Human bone marrow-derived MSCs can be extracted relatively simply from the marrow of adult patients and maintained and expanded in culture. More importantly, it has been previously demonstrated that MSCs have the capacity to differentiate into neurons and glia in vitro when grown under appropriate conditions. Multipotent MSCs have also been successfully used in transplantation studies in animal models of disease as diverse as demyelination, stroke, trauma and Parkinson's disease. MSCs therefore provide an attractive and practical source of stem cells for reparative therapy in patients, and in this paper we describe methods for the reproducible culture and neural differentiation of human MSCs generated from patient marrow.

Adult stem cells for the treatment of neurological disease

The characteristic CNS responses to injury including increased cell production and attempts at regenerative repair - implicitly predicted where not directly demonstrated by Cajal, but only now more fully confirmed - have important implications for regenerative therapies. Spontaneous CNS cell replacement compares poorly with the regenerative functional repair seen elsewhere, but harnessing, stimulating or supplementing this process represents a new and attractive therapeutic concept.Stem cells, traditionally defined as clone-forming, self-renewing, pluripotent progenitor cells, have already proved themselves to be an invaluable source of transplantation material in several clinical settings, most notably haematological malignancy, and attention is now turning to a wider variety of diseases in which there may be potential for therapeutic intervention with stem cell transplantation. Neurological diseases, with their reputation for relentless progression and incurability are particularly tantalising targets. The optimal source of stem cells remains to be determined but bone marrow stem cells may themselves be included amongst the contenders.Any development of therapies using stem cells must depend on an underlying knowledge of their basic biology. The haemopoietic system has long been known to maintain circulating populations of cells with short life spans, and this system has greatly informed our knowledge of stem cell biology. In particular, it has helped yield the traditional stem cell model - a hierarchical paradigm of progressive lineage restriction. As cells differentiate, their fate choices become progressively more limited, and their capacity for proliferation reduced, until fully differentiated, mitotically quiescent cells are generated. Even this, however, is now under challenge.

Human mesenchymal stem cells abrogate experimental allergic encephalomyelitis after intraperitoneal injection, and with sparse CNS infiltration

Multiple sclerosis is a currently incurable inflammatory demyelinating syndrome. Recent reports suggest that bone marrow derived mesenchymal stem cells may have therapeutic potential in experimental models of demyelinating disease, but various alternative mechanisms, ranging from systemic immune effects to local cell replacement, have been proposed. Here we used intraperitoneal delivery of human mesenchymal stem cells to help test (a) whether human cells can indeed suppress disease, and (b) whether CNS infiltration is required for any beneficial effect. We found pronounced amelioration of clinical disease but profoundly little CNS infiltration. Our findings therefore help confirm the therapeutic potential of mesenchymal stem cells, show that this does indeed extend to human cells, and are consistent with a peripheral or systemic immune effect of human MSCs in this model.

Accidental carbon monoxide poisoning presenting without a history of exposure: a case report

Introduction

Carbon monoxide poisoning is easy to diagnose when there is a history of exposure. When the exposure history is absent, or delayed, the diagnosis is more difficult and relies on recognising the importance of multi-system disease. We present a case of accidental carbon monoxide poisoning.

Case presentation

A middle-aged man, who lived alone in his mobile home was found by friends in a confused, incontinent state. Initial signs included respiratory failure, cardiac ischaemia, hypotension, encephalopathy and a rash, whilst subsequent features included rhabdomyolysis, renal failure, amnesia, dysarthria, parkinsonism, peripheral neuropathy, supranuclear gaze palsy and cerebral haemorrhage. Despite numerous investigations including magnetic resonance cerebral imaging, lumbar puncture, skin biopsy, muscle biopsy and electroencephalogram a diagnosis remained elusive. Several weeks after admission, diagnostic breakthrough was achieved when the gradual resolution of the patient's amnesia, encephalopathy and dysarthria allowed an accurate history to be taken for the first time. The patient's last recollection was turning on his gas heating for the first time since the spring. A gas heating engineer found the patient's gas boiler to be in a dangerous state of disrepair and it was immediately decommissioned.

Conclusion

This case highlights several important issues: the bewildering myriad of clinical features of carbon monoxide poisoning, the importance of making the diagnosis even at a late stage and preventing the patient's return to a potentially fatal toxic environment, and the paramount importance of the history in the diagnostic method.

Campath 1-H treatment in patients with aggressive relapsing remitting multiple sclerosis

Campath 1-H (Alemtuzumab) is a humanised monoclonal antibody which targets the CD52 antigen, a low molecular weight glycoprotein present on the surface of most lymphocyte lineages, causing complement mediated lysis and rapid and prolonged T lymphocyte depletion. Following encouraging initial data from other centres we report our open label experience of using Campath 1-H as a treatment in aggressive relapsing multiple sclerosis in a consecutive series of 39 highly selected patients treated across three regional centres and followed for a mean of 1.89 years. The mean annualised relapse rate fell from 2.48 pre treatment to 0.19 post treatment with 29% of documented relapses observed in the 12 weeks following initial infusion. Mean change in EDSS was -0.36 overall and -0.15 in those patients completing > or =1 year of follow- up. Eighty-three per cent of patients had stable or improved disability following treatment. Infusion related side effects were common including rash, headache and pyrexia but were usually mild and self limiting. Transient worsening of pre-existing neurological deficits during infusion was observed in 3 patients. 12 patients developed biochemical evidence of autoimmune dysfunction, 2 patients developed thyroid disease and 1 patient autoimmune skin disease. We conclude that relapse rates fall following Campath 1-H. Whilst side effects were common these were normally self limiting or easily managed, suggesting Campath 1-H may be of use in the treatment of very active relapsing remitting multiple sclerosis.

CNS lupus: A study of 41 patients

BACKGROUND

CNS lupus is a serious but potentially treatable illness, which, though long recognized, may still present very difficult diagnostic challenges. We believed that further detailed study of patients with neuropsychiatric lupus would yield clinical information of practical value in improving both recognition and management of this difficult illness.

METHODS

A retrospective case analysis of 41 patients with CNS systemic lupus erythematosus (CNS-SLE) was performed largely in the southwest of England and South Wales, covering the period 1990 to 2002.

RESULTS

We found that primary neurologic presentation of SLE was not rare (10/41 patients), and there was an unexpected emergence of movement disorders (particularly parkinsonism and myoclonus) early in the disease course (4/10 patients). These showed a good response to immunosuppressants, but not to standard dopaminergic therapy. Typically, the erythrocyte sedimentation rate (ESR) or plasma viscosity was elevated during neurologic episodes while C-reactive protein levels were normal, and lupus-related serum antibody tests usually supportive. But, significantly, neither a normal ESR nor negative serology excluded CNS lupus. MR brain imaging is more commonly abnormal in patients with focal neurologic deficits and normal or shows wholly nonspecific change with more diffuse manifestations (cognitive decline, epilepsy). Abnormal CSF correlated significantly with poorer outcome. At the end of the period of study, 54% had no more than minor functional disability, the remainder having a severe or fatal outcome.

CONCLUSIONS

Our observations, particularly the emergence of non-choreic movement disorders, the blood, serum, and imaging findings, and the prognostic importance of CSF abnormalities, should help improve both the recognition of CNS systemic lupus erythematosus, perhaps particularly in elderly individuals, and its management.

Sarcoidosis of the nervous system

Although sarcoidosis is rarely confined to the nervous system, any neurological features that do occur frequently happen early in the course of the disease. The most common neurological presentation is with cranial neuropathies, but seizures, chronic meningitis and the effects of mass lesions are also frequent. The diagnostic process should first confirm nervous system involvement and then provide supportive evidence for the underlying disease; in the absence of any positive tissue biopsy, the most useful diagnostic tests are gadolinium enhanced MRI of the brain and CSF analysis, although both are non-specific. The mainstay of treatment is corticosteroids, but these often have to be combined with other immunosuppressants such as methotrexate, hydroxychloroquine or cyclophosphamide. There is increasing evidence that infliximab is a safe treatment with good steroid sparing capacity.

Autologous bone marrow stem cells--properties and advantages

The properties of self-renewal and multi-lineage differentiation make stem cells attractive candidates for use in cellular reparative therapy, particularly in neurological diseases where there is a paucity of treatment options. However, clinical trials using foetal material in Parkinson's disease have been disappointing and highlighted problems associated with the use of embryonic stem cells, including ethical issues and practical concerns regarding teratoma formation. Understandably, this has led investigators to explore alternative sources of stem cells for transplantation. The expression of neuroectodermal markers by cells of bone marrow origin focused attention on these adult stem cells. Although early enthusiasm has been tempered by dispute regarding the validity of reports of in vitro (trans)differentiation, the demonstration of functional benefit in animal models of neurological disease is encouraging. Here we will review some of the required properties of stem cells for use in transplantation therapy with specific reference to the development of bone marrow-derived cells as a source of cells for repair in demyelination.

Neuro-Behçet's disease in Caucasians: a study of 22 patients

Several analyses of the neurological features of Behçet's disease (BD) have concluded that there are significant racial differences in its clinical expression. Other series, however, failed to elicit such differences. We aimed to describe in this retrospective survey the frequency, nature and relationship to systemic disease of the neurological features in a cohort of BD patients of Caucasian origin. We searched hospital records from nine District General or Regional Centre hospitals in south-west Great Britain and identified 22 individuals of Caucasian ethnic origin with neuro-BD, with a mean of 10 years follow-up per patient - the largest 'western' case series with the longest period of follow-up reported. We found that presentation with neurological features was commoner in our patients (23%) than Middle Eastern series (3-10%). Seizures (27%) were likewise commoner (0-5%), as was optic neuritis (9% compared with 1-2%). Two patients developed movement disorders (chorea and parkinsonism), which have only been rarely reported. Of further clinical significance, we noted that non-neuropsychiatric features: oral ulceration, intraocular inflammation and skin lesions - were virtually always present or exacerbated during neurological complications. Ethnicity--or conceivably environment--may play a significant role in the manifestation of neurological BD.

Co-expression of PDGF alpha receptor and NG2 by oligodendrocyte precursors in human CNS and multiple sclerosis lesions

Following inflammatory demyelination in multiple sclerosis (MS), partial remyelination occurs. Studies in rodents have indicated that oligodendrocyte precursor cells (OPCs) are responsible for this remyelination. Rodent OPCs are identified in situ with antibodies against platelet-derived growth factor alpha receptor (PDGFalphaR) and NG2 chondroitin sulfate proteoglycan. In human CNS tissue, studies of NG2 and PDGFalphaR expression are limited and controversy exists as to whether these molecules are specific OPC markers. This study has investigated whether PDGFalphaR and NG2 are co-expressed on OPCs in human CNS, and whether OPCs are associated with remyelination in MS. MS brain tissue was examined for PDGFalphaR and NG2 immunoreactivity and for expression of NG2 mRNA by in situ hybridisation. Putative OPCs, expressing both NG2 and PDGFalphaR, were present within normal-appearing white matter and within areas of active demyelination in MS, but not in chronic silent lesions. They were also seen in association with remyelination in MS tissue and with developmental myelination in human spinal cord. NG2+ cells that did not express PDGFalphaR were also detected. Given their lack of reactivity with microglial or astrocyte markers, these NG2+/PDGFalphaR- cells probably represented more mature OPCs that had lost PDGFalphaR expression. The distribution of OPCs observed in this study strongly suggests these cells are potential sources of remyelinating oligodendrocytes in active lesions in MS.

Disclosing the diagnosis of multiple sclerosis

CONTEXT

The question of how best to disclose to patients the diagnosis of serious and/or incurable neurological diseases has been much explored, but that of when has received little rigorous study. The present study investigates this question in relation to multiple sclerosis (MS), a disease marked by its incurability, unpredictability and predilection for young adults.

OBJECTIVES

We aimed to ascertain the preferences of Greek MS sufferers concerning when they should ideally be informed they have the disease, and their preferences and reactions regarding disclosure of the diagnosis. Design, setting and patients 1,200 Greek MS patients,members of the MS Society, were asked to complete a questionnaire regarding their experience of and attitudes towards receiving the diagnosis.

DESIGN, SETTING AND PATIENTS

1,200 Greek MS patients,members of the MS Society, were asked to complete a questionnaire regarding their experience of and attitudes towards receiving the diagnosis.

RESULTS

657 patients (55 %) responded. 91% favoured learning the diagnosis immediately, but only 44% had had this experience: 29% had been informed within 1-3 years, and 27% later. Interestingly, however, a significant minority (9 %) suggested a possible preference for delayed delivery of diagnosis and 23.2% stated that concealing the diagnosis would not lead to loss of confidence in their doctor.

CONCLUSION

This study-the largest of its kind-provides objective data supporting prompt disclosure of diagnosis as the clearly-expressed preference amongst most patients. Interestingly, however, the results also re-emphasise the importance of a difficult medical art: attempting to judge whether an individual patient is one (of the 91%) preferring immediate disclosure-or of the nearly 1-in-10 (9%) who may not.

Abeta-related angiitis: primary angiitis of the central nervous system associated with cerebral amyloid angiopathy

Idiopathic or primary angiitis of the CNS (PACNS) and cerebral amyloid angiopathy (CAA) are unusual vasculopathies generally regarded as unrelated disorders. A few case reports have, however, described granulomatous angiitis in patients with sporadic, amyloid beta peptide (Abeta)-related CAA. Here we describe the clinical, neuroradiological and neuropathological features of nine patients with Abeta-related angiitis (ABRA). Combining these with the individual case reports drawn from the literature has allowed us to define ABRA as a clinical entity and to compare its features with those of PACNS. The mean age of presentation of ABRA (67 years) is higher than that of PACNS but lower than that of sporadic non-inflammatory Abeta-related CAA. Alterations in mental status (59%), headaches (35%), seizures and focal neurological deficits (24%) are common. Hallucinations are a presenting manifestation in 12% of cases. Most patients have white matter hyperintensities on MRI but these are of similar appearance to those in PACNS. Cerebrospinal fluid usually shows modest elevation of protein and pleocytosis. Neuropathology reveals angiodestructive inflammation, often granulomatous, and meningeal lymphocytosis. Abeta is consistently present in abundance in affected blood vessels but usually scanty within the parenchyma of the cerebral cortex. However, the cortex includes numerous activated microglia, occasionally in a plaque-like distribution and containing cytoplasmic Abeta. The cerebral white matter shows patchy gliosis and rarefaction, in some cases marked. Our findings (i) help to dissect one separate clinicopathological entity from what is likely to be a spectrum of primary angiitides of the CNS; (ii) have important therapeutic implications for one category of patients with amyloid-related vasculopathy; and (iii) may provide valuable insights into the development of amyloid-associated inflammation, of relevance not only to ABRA but also to Abeta-immunization-related encephalitis and to Alzheimer's disease.

Neural progenitor cells from postmortem adult human retina

BACKGROUND

Given the presence of neural progenitor cells (NPC) in the retina of other species capable of differentiating into multiple neural components, the authors report the presence of NPC in the adult human retina. A resident population of NPC suggests that the retina may constitutively replace neurons, photoreceptors, and glia.

METHODS

Adult human postmortem retinal explants and cell suspensions were used to generate cells in tissue culture that display the features of NPC. The phenotype of cells and differentiation into neurons was determined by immunocytochemistry. Dividing cells were labelled with 5-bromo-2-deoxyuridine (BrdU) and neurospheres were generated and passaged.

RESULTS

Cells labelled with nestin, neurofilament M (NFM), rhodopsin, or glial fibrillary acidic protein (GFAP) grew out from explant cultures. BrdU labelling of these cells occurred only with basic fibroblast growth factor (FGF-2). Dissociated retina and pars plana generated primary neurospheres. From primary neurospheres, NPC were passaged to generate secondary neurospheres, neurons, photoreceptors, and glia. BrdU labelling identified dividing cells from neurospheres that differentiated to express NFM and rhodopsin.

CONCLUSION

The adult human retina contains NPC and may have the potential to replace neurons and photoreceptors. This has implications for the pathogenesis and treatment of retinal disorders and degenerations, including glaucoma, and those disorders associated with retinal scarring.

Metabotropic glutamate receptors are expressed in adult human glial progenitor cells

Glial precursor cells (GPCs) are present in the adult human central nervous system (CNS) and they can be isolated and maintained in culture for in vitro studies. This study analysed expression of mGluR3 and mGluR5 metabotropic glutamate receptor (mGluR) mRNAs in GPCs. A2B5 surface antigen positive GPCs were isolated using immunomagnetic selection from dissociated temporal lobe subcortical white matter cells. The separated GPCs were maintained in cultures and characterised by immunoreactivity for the differentiation markers A2B5 and human platelet-derived growth factor-alpha receptor (PDGFalphaR). Reverse transcription followed by multiplex PCR analysis showed that the GPCs expressed both mGluR3 and mGluR5a mRNAs. Double immunostaining for glial progenitor markers and mGluR5 proteins demonstrated that all A2B5 and PDGFalphaR-positive cells were also positive for mGluR5. The results indicate that GPCs present in the adult human CNS express mGluR3 and mGluR5a. These neurotransmitter receptors may be involved in the proliferation and differentiation of glial cells.

Adult stem cells--reprogramming neurological repair?

Much excitement has surrounded recent breakthroughs in embryonic stem-cell research. Of lower profile, but no less exciting, are the advances in the field of adult stem-cell research, and their implications for cell therapy. Clinical experience from use of adult haemopoietic stem cells in haematology will facilitate and hasten transition from laboratory to clinic--indeed, clinical trials using adult human stem cells are already in progress in some disease states, including myocardial ischaemia. Here, with particular reference to neurology, we review processes that might underlie apparent changes in adult cell phenotype. We discuss implications these processes might have for the development of new therapeutic strategies using adult stem cells.

S1P and LPA trigger Schwann cell actin changes and migration

The processes by which a Schwann cell (SC) migrates towards, wraps around and, in some cases, myelinates an axon are incompletely understood. The complex morphological rearrangements involved in these events require fundamental changes in the actin cytoskeleton. Sphingosine 1-phosphate (S1P) and lysophosphatidic acid (LPA) are two modulators of the actin cytoskeleton, and receptors for these signalling lipids are expressed on SCs at the time of differentiation. Previous work has revealed a role for LPA in SC survival, morphology and differentiation, but the effects of S1P have received less attention. Here we show that S1P and LPA both cause major rearrangements to the actin cytoskeleton in primary rat SCs and the SCL4.1/F7 rat SC line. S1P and LPA caused formation of lamellipodia and a circular geodesic actin network. We also show that S1P and LPA increased cell migration. The small GTPases RhoA and Rac1 were both activated by S1P/LPA treatment, but the actin rearrangements were dependent on Rac1 and not RhoA. These effects of S1P/LPA could be mimicked by SCL4.1/F7 cell-conditioned medium, which was found to contain S1P. Reduction in cellular synthesis of S1P by adding the sphingosine kinase inhibitor dimethyl sphingosine during medium conditioning reduced the ability of conditioned medium to cause actin rearrangements. These results support a role for S1P as an autocrine signal regulating the actin cytoskeleton during Schwann cell development.

Stem cells for the treatment of neurological disease

Stem cells are widely believed to have significant potential in the treatment of human disease. Comments such as '[stem cells]...could prove the Holy Grail in finding treatments for cancer, Parkinson's disease, diabetes, osteoporosis, spinal cord injuries, Alzheimer's disease, leukaemia and multiple sclerosis...transform[ing] the lives of hundreds of thousands of people' (Yvette Cooper, Public Health minister, quoted in The Times, December 16 2000, authors' italics) serve to reinforce the extraordinary expectations of stem cells, particularly in neurological disease. Stem cells, traditionally defined as clone forming, self-renewing, pluripotent, progenitor cells, have already proved themselves to be an invaluable source of transplantation material in several clinical settings, most notably malignant haematology, and attention is now turning to a wider variety of diseases in which there may be potential for therapeutic intervention with stem cell transplantation. Neurological diseases have been highlighted as a priority and this is understandable given their unenviable reputation for relentless progression and the paucity of disease-modifying treatments. However, it is important that the potential of stem cells to treat neurological disease is critically appraised if the hopes of patients and doctors are not to be raised without foundation.

Immune-modifying agents do not impair the survival, migration or proliferation of oligodendrocyte progenitors (CG-4) in vitro

Limited intrinsic myelin repair occurs in multiple sclerosis (MS), mediated by oligodendrocyte progenitors that divide and migrate into demyelinated lesions. Experimental remyelination suggests that this repair restores function and may protect axons from subsequent degeneration. Immunomodulatory drugs such as corticosteroids, interferon-beta and azathioprine are widely used in MS. However, their influence on disease progression is modest, for reasons that are not fully explained. The direct effects of these drugs on remyelination biology remain relatively unexplored. We have investigated the effect of these MS therapies on oligodendrocyte progenitors to identify whether drug treatment might directly compromise repair, either therapeutic or spontaneous. None of these drugs affected CG-4 survival, migration or proliferation.

Continuing optic nerve atrophy following optic neuritis: a serial MRI study

To investigate optic neuritis as a model for atrophy in multiple sclerosis (MS) lesions we performed serial magnetic resonance imaging (MRI) on 10 patients with a history of optic neuritis using a fat saturated short-echo fast fluid-attenuated inversion recovery (sTE fFLAIR) sequence. The first study was performed a median of 19.5 months after the onset of optic neuritis and the second 1 year later. Using a computer-assisted contouring technique, a blinded observer calculated the mean area of the intro-orbital optic nerves. The mean area of affected optic nerves decreased over 1 year by 0.9 mm2 from 11.1 to 10.2 mm2 (p = 0.01). Poor visual acuity and decreased visual-evoked potential (VEP) amplitude were associated with atrophy. These findings suggest that atrophy is a feature of focal demyelinating lesions, it may evolve over several years, and may have functional significance. Optic neuritis provides a model to study the effect of inflammatory demyelination through the ability to accurately measure visual function and to visualize and measure the optic nerves using magnetic resonance imaging.

The recognition, diagnosis and management of cerebral vasculitis: a European survey

We have completed a survey of European neurological practice concerning cerebral vasculitis. Twenty-nine respondents from 15 countries provided information concerning the diagnosis and management. The results confirmed the anticipated low frequency of the disease, but also illustrated the power of any putative collaborative effort. Interestingly, there was a wide variation in clinical practice, in particular concerning the perceived importance of cerebral angiography as a diagnostic test and the very common use of steroids as first-line treatment, rather than more potent immunosuppressive agents. This variation is probably to be explained at least, in part, by the absence of any firm evidence base to inform clinical practice. A European collaborative effort--in which there has emerged considerable interest--offers a realistic opportunity to generate sound clinical evidence and thence scientifically robust practical guidelines.

The neuropathology and pathogenesis of systemic lupus erythematosus

Systemic lupus erythematosus (SLE) is a chronic, multisystem, autoimmune disease in which neuropsychiatric involvement occurs in about 50% of patients and carries a poor prognosis. Despite extensive research, the precise mechanisms of nervous tissue injury remain the least well understood. This article summarizes the important clinical neuropsychiatric features of SLE and, reviewing classical histopathological and more recent experimental studies, discusses theories concerning their presumed pathogenesis. The distinctive production of diverse autoantibodies seems to be related to defective clearance of apoptotic cells. Antibody-mediated neural cell injury and rheological disturbances represent the two principal suggested mechanisms of tissue injury. An interplay between these processes, underlying genetic factors, their modification by hormones, complicated by a number of secondary factors, may explain the wide spectrum of features encountered in this disease.

Remyelination of demyelinated CNS axons by transplanted human schwann cells: the deleterious effect of contaminating fibroblasts

Areas of demyelination can be remyelinated by transplanting myelin-forming cells. Schwann cells are the naturally remyelinating cells of the peripheral nervous system and have a number of features that may make them attractive for cell implantation therapies in multiple sclerosis, in which spontaneous but limited Schwann cell remyelination has been well documented. Schwann cells can be expanded in vitro, potentially affording the opportunity of autologous transplantation; and they might also be spared the demyelinating process in multiple sclerosis. Although rat, cat, and monkey Schwann cells have been transplanted into rodent demyelinating lesions, the behavior of transplanted human Schwann cells has not been evaluated. In this study we examined the consequences of injecting human Schwann cells into areas of acute demyelination in the spinal cords of adult rats. We found that transplants containing significant fibroblast contamination resulted in deposition of large amounts of collagen and extensive axonal degeneration. However, Schwann cell preparations that had been purified by positive immunoselection using antibodies to human low-affinity nerve growth factor receptor containing less than 10% fibroblasts were associated with remyelination. This result indicates that fibroblast contamination of human Schwann cells represents a greater problem than would have been appreciated from previous studies.

Infratentorial hypointense lesion volume on T1-weighted magnetic resonance imaging correlates with disability in patients with chronic cerebellar ataxia due to multiple sclerosis

In multiple sclerosis (MS), hypointense lesions on T1-weighted magnetic resonance imaging are thought to represent areas of tissue disruption and axonal loss. In previous studies of MS patients, infratentorial T1 hypointense lesions were found to be rare. In MS patients selected to have chronic cerebellar ataxia, we have determined the extent of infratentorial T1 hypointense lesions and their relationship with disability. We recruited nine patients with chronic cerebellar ataxia due to MS. An expanded disability status scale (EDSS) assessment was performed on each. The patients' brains were then imaged with axial-oblique dual-echo fast spin-echo and contrast-enhanced T1-weighted conventional spin-echo sequences. The number and total volume of infratentorial high-signal lesions on T2-weighted images and infratentorial hypointense lesions on T1-weighted images were calculated by a blinded observer using a computer-assisted contouring technique. A total of 96 infratentorial high-signal lesions were present, of which 62 (64.6%) appeared isointense and 34 (35.4%) hypointense with respect to the surrounding brain substance on the T1-weighted images. There was a median of 3 (range 0-10) and median volume of 0.43 ml (range 0-0.85 ml) infratentorial T1 hypointense lesions per patient. The EDSS score correlated with both the number (r=0.68, p=0.043) and the volume per patient (r=0.89, p=0.001) of infratentorial T1 hypointense but not T2 high-signal lesions. Infratentorial T1 hypointense lesions are often seen in patients with MS and chronic cerebellar ataxia. They may play a significant role in the disability suffered by these patients.

Detection of optic nerve atrophy following a single episode of unilateral optic neuritis by MRI using a fat-saturated short-echo fast FLAIR sequence

We describe an MRI technique for quantifying optic nerve atrophy resulting from a single episode of unilateral optic neuritis. We imaged 17 patients, with a median time since onset of optic neuritis of 21 months (range 3-81 months), using a coronal-oblique fat-saturated short-echo fast fluid-attenuated inversion-recovery (sTE fFLAIR) sequence. The mean cross-sectional area of the intraorbital portion of the optic nerves was calculated by a blinded observer from five consecutive 3 mm slices from the orbital apex forwards using a semiautomated contouring technique and compared with data from 16 controls. The mean optic nerve area was 11.2 mm2 in the affected eye of the patients, 12.9 mm2 in the contralateral eye (P = 0.006 compared to the affected eye) and 12.8 mm2 in controls (P = 0.03 compared to the affected eyes). There was a significant negative correlation between disease duration and the size of the affected optic nerve (r = -0.59, P = 0.012). The measurement coefficient of variation was 4.8%. The sTE fFLAIR sequence enables measurement of optic nerve area with sufficient reproducibility to show optic nerve atrophy following a single episode of unilateral optic neuritis. The correlation of increasing optic nerve atrophy with disease duration would be consistent with ongoing axonal loss in a persistently demyelinated lesion, or Wallerian degeneration following axonal damage during the acute inflammatory phase.

Normal polyclonal immunoglobulins ('IVIg') inhibit microglial phagocytosis in vitro

Phagocytosis removes pathogens and tissue debris during inflammatory reactions, but also plays an important role in autoimmune reactions. The main phagocytes in the central nervous system (CNS) are microglial cells that are activated during CNS inflammation. In the treatment of inflammatory demyelinating diseases like multiple sclerosis (MS), administration of intravenous immunoglobulins (IVIg) has become a promising immunomodulatory therapy. Although a large number of potential mechanisms for the effects of IVIg has been suggested, the precise mode of action in CNS inflammation is unknown. We assessed the influence of IVIg on phagocytosis and endocytosis in microglia in vitro. IVIg had little effect on non-specific phagocytosis of latex particles in untreated microglia, while there was a dose-dependent inhibition in microglia activated with LPS and IFNgamma. Endocytosis of soluble myelin basic protein (MBP) was downregulated by IVIg in both untreated and activated microglia. The effect was mediated by an F(ab')(2) preparation of immunoglobulins, suggesting that Fc receptor-mediated phagocytosis is not involved. Intact IVIg, but not F(ab')(2) fragments also suppressed Fc receptor-mediated phagocytosis of opsonised erythrocytes in both untreated and activated microglia. These results show that IVIg can inhibit the phagocytic activity of microglia via different mechanisms. Such an effect could contribute to the immunomodulatory capacity of IVIg in inflammatory CNS diseases.

Oligodendroglia are protected from antibody-mediated complement injury by normal immunoglobulins ("IVIg")

High-dose intravenous immunoglobulin (IVIg) treatment has become a promising immune therapy that can modulate the immune system at several levels, including the complement cascade. In relation to inflammatory demyelinating disease, there is some clinical evidence for the suppression of disease activity by IVIg, while a role in promoting remyelination after experimental myelin damage has been described. Antibody and complement deposition have been implicated in the immune attack in some cases of multiple sclerosis (MS), and to investigate the mechanisms of action of IVIg, we studied the effect of IVIg using the model of complement-mediated cell injury on oligodendroglia in vitro. There was no effect on direct complement lysis of the oligodendroglial cell line CG4, but antibody-dependent complement damage was inhibited in a dose-dependent manner by IVIg. These results were confirmed with primary cultures of oligodendrocyte precursor cells (OPC) and oligodendrocytes. The addition of excess C1, C3, and C4 did not influence the inhibitory effect of IVIg, implying that binding of these complement components does not play a role, in contrast to other experimental models of complement damage. F(ab')2 immunoglobulin fragments were at least partially responsible for the effect. We conclude that IVIg may be protective in antibody-mediated complement injury of oligodendrocytes and their progenitors, and that this effect is likely to be mediated via antibody binding, rather than interference with complement activation. Inhibition of inflammatory mechanisms, as opposed to a direct effect on remyelinating cells, may underlie the role of IVIg in promoting myelin repair in experimental models.

Mechanisms of damage to myelin and oligodendrocytes and their relevance to disease

Oligodendrocytes synthesize and maintain myelin in the central nervous system (CNS). Damage may occur to these cells in a number of conditions, including infections, exposure to toxins, injury, degeneration, or autoimmune disease, arising both in the course of human disease and in experimental animal models of demyelination and dysmyelination; multiple sclerosis is the commonest human demyelinating disorder. Conventional classical accounts of the pathology of this and other myelin diseases have given great insights into their core features, but there remain considerable uncertainties concerning the timing, means and cause(s) of oligodendrocyte and myelin damage. At present, therapeutic efforts largely concentrate on immune manipulation and damage limitation, an approach that has produced only modest effects in multiple sclerosis. One reason for this must be the limited understanding of the mechanisms underlying cell damage - clearly, successful therapeutic strategies for preserving the oligodendrocyte-myelin unit must depend on knowledge of how oligodendrocyte damage and death occurs. In this review, mechanisms of oligodendrocyte and myelin damage are considered, and attempts made to relate them to disease processes, clinical and experimental. The hallmarks of different cell death processes are described, and oligodendrocyte-myelin injury by cellular and soluble mediators is discussed, both in vitro and invivo. Recent developments concerning the pathological involvement of oligodendrocytes in neurodegenerative disease are summarized. Finally, these neuropathological and applied neurobiological observations are drawn together in the context of multiple sclerosis.

Polyclonal immunoglobulins for intravenous use do not influence the behaviour of cultured oligodendrocytes

Treatment studies in multiple sclerosis and the experimental murine model of Theiler's virus encephalomyelitis have suggested that intravenous immunoglobulins (IVIg) promote central nervous system remyelination. It is not clear if this results from a direct effect on myelinating oligodendroglial cells, or from suppression of the immune response permitting better endogenous repair. We systematically explored the effects of IVIg on various aspects of oligodendrocyte precursor cell (OPC) behaviour in vitro. Neither proliferation, differentiation nor migration of OPC was affected by IVIg. These results argue against a direct effect of IVIg on remyelination and are in favour of an indirect yet not clearly defined mechanism that supports remyelination.

Microangiopathy of the brain and retina with hearing loss in a 50 year old woman: extending the spectrum of Susac's syndrome

A 50 year old woman presented with a subacute onset of vertigo and diplopia followed by an encephalopathy with confusion, spasticity, ataxia, myoclonus, and multiple branch retinal arteriolar occlusions and unilateral sensorineural deafness. Brain biopsy confirmed multiple microinfarcts with no vasculitis. After the procedure she had a right iliofemoral deep vein thrombosis and was found to be heterozygous for the factor V Leiden mutation. She was treated with anticoagulants and made a marked recovery with no relapses 6 months after presentation. This case extends the age range at which Susac's syndrome can present, and raises the possibility that the condition may be associated with abnormalities of coagulation.

Identification of A2B5-positive putative oligodendrocyte progenitor cells and A2B5-positive astrocytes in adult human white matter

Spontaneous remyelination of previously demyelinated axons is found in a substantial minority of acute and chronic lesions in multiple sclerosis. In the rodent, central remyelination restores saltatory conduction and helps restore limb function, and it seems likely that endogenous myelin repair contributes to neurological recovery in multiple sclerosis. However, the identity of the remyelinating cell remains enigmatic. Fully differentiated oligodendrocytes have very limited capacity for recapitulating their developmental activities and re-engaging myelination pathways. Proliferative oligodendrocyte progenitors--often known as O-2A cells because of their ability to differentiate in vitro into either oligodendrocytes or ("type 2") astrocytes--are, in contrast, extremely efficient at myelin repair either spontaneously, or after transplantation into the de- or dysmyelinated CNS. Oligodendrocyte progenitors are present in both developing and adult rodent CNS. We have previously demonstrated that proliferative oligodendrocyte progenitors are present in cultures prepared from the adult human CNS. Here, using fresh tissue print preparations, we report that cells with processes and the A2B5-positive immunophenotype of proliferative oligodendrocyte progenitors are present in situ in adult human white matter. This technique also reveals the occurrence of A2B5-positive astrocytes, a cell also not previously identified in the normal adult human CNS. In the light of the rodent data showing the importance of oligodendrocyte progenitors in myelin repair, our findings suggesting the presence of progenitors in the adult human brain may have significant implications for spontaneous remyelination in multiple sclerosis and other demyelinating conditions.

Central nervous system sarcoidosis--diagnosis and management

A series of 68 patients with neurosarcoidosis is reported, with particular emphasis on clinical aspects, diagnosis and treatment. A classification system based on clinical diagnostic probability is proposed, consisting of probable and definite disease, the latter being dependent on finding sarcoid granulomas on nervous system histology, which was obtained in 12 patients (18%). The role of investigations, including magnetic resonance imaging (MRI), chest radiography, Kveim skin test, Gallium 67 isotope scanning and cerebrospinal fluid (CSF) studies, is considered. Sixty-two percent of patients presented with nervous system disease, most commonly affecting the optic nerve and chiasm. Other common presentations included cranial nerve palsies, spinal cord and brainstem manifestations. Investigations yielding most diagnostic information included the Kveim test (41/48, 85% positive), raised CSF protein and/or cells (50/62, 81%) and gallium 67 scan (14/31, 45%). Eleven out of 29 patients (38%) patients showed meningeal enhancement on MRI scanning and 43% of scans demonstrated multiple white-matter lesions. Mean follow-up for the group was 4.6 years. Forty-seven patients were seen for > 18 months, and over half of these patients progressed despite corticosteroid and other immunosuppressive therapies. The benefit of a large patient database prospectively studied, with extended follow-up is discussed in order to learn more about prognosis and advance therapy in neurosarcoidosis.

Adult polyglucosan body disease associated with an extrapyramidal syndrome

A 50 year old patient is described who presented with parkinsonism, frontal dementia, peripheral neuropathy, neurogenic bladder, and upper motor neuron signs. No improvement in objective measurements of extrapyramidal dysfunction were seen with an incremental apomorphine test or more prolonged oral dopamine challenge. Neurophysiology disclosed changes compatible with a diffuse axonal neuropathy and pathological examination of a length of sural nerve taken at biopsy showed multiple polyglucosan bodies characteristic of adult polyglucosan body disease (APGBD). This case underlines the diverse clinical presentation of this rare neurological disease and the importance of recognising the unusual association of clinical features in making the diagnosis. APGBD should be included in the differential diagnosis of parkinsonism unresponsive to dopaminergic therapy.

Interferon-beta inhibits mitogen induced astrocyte proliferation in vitro

The central nervous system response to injury and inflammation commonly includes astrocytosis. This process, which is manifest by astrocyte hypertrophy and proliferation, is particularly prominent in multiple sclerosis (MS), where in chronic lesions it may contribute to the lack of repair by restricting the migration of remyelinating cells. Interferon-beta (IFN-beta) modestly reduces the frequency of relapses in MS and may have a small effect on the accumulation of permanent disability. Here, we show that IFN-beta inhibits the in vitro proliferative response of rodent astrocytes to a wide variety of growth factors and cytokines. Although important species differences exist in these glial responses this previously unrecognised property of IFN-beta may have implications for reducing astrocytosis and thereby promoting endogenous repair.

The expression of complement regulatory proteins by adult human oligodendrocytes

In multiple sclerosis, infiltrating T lymphocytes and perivascular microglia may initiate demyelinating lesions, but a role for antibody and complement in the ensuing inflammatory damage to myelin and oligodendrocytes is likely. In most tissues, ubiquitously expressed complement regulatory proteins prevent autologous destruction, protecting host cells from the powerful cytolytic activity of activated complement. We have studied the surface expression of a comprehensive range of complement regulatory proteins by live adult human oligodendrocytes in vitro. Only DAF of the activation pathway regulators was expressed, not CR1 or MCP. Of the membrane attack pathway regulatory proteins, HRF was not expressed, while substantial heterogeneity of CD59 expression by oligodendrocytes was found. Clusterin expression was not found. A relative deficiency of protective complement regulatory proteins on human oligodendrocytes may contribute to their selective damage in multiple sclerosis.

Remyelination in demyelinating disease

In multiple sclerosis, partial remyelination is conspicuous in many lesions, and is thought to contribute significantly to lasting recovery from acute relapse. However, myelin repair ultimately fails during progression of the disease, as disability and handicap accumulate. In this chapter we explore the biological background to myelin repair in CNS demyelinating disease, and the reasons underlying the failure of more widespread and lasting remyelination in multiple sclerosis. Experimental studies provide clear evidence that therapies promoting myelin repair can be highly successful in the CNS, and we discuss the clinical approaches which might allow the translation of these laboratory studies to neurological practice, together with some of the potential hazards and pitfalls likely to arise.

Beta-interferon and multiple sclerosis

Interferon-beta (IFN-beta) is the first therapeutic intervention shown to alter the natural history of multiple sclerosis (MS), a relapsing then progressive inflammatory degenerative disease of the CNS. Since publication of the first randomized placebo-controlled trial of IFN-beta, and subsequent acquisition of US and European product licences for use in relapsing-remitting MS, the hopes and expectations of patients have been elevated greatly only to be dampened as more critical analysis of the trial results, in conjunction with the cost of treatment, led to marked limitations on prescription in several countries. IFN-beta is not a cure. Here we review what is known about the mechanisms of action of IFN-beta in demyelinating disease, and propose a possible model of action of IFN-beta in the treatment of MS.

Cerebral vasculitis--recognition, diagnosis and management

Cerebral vasculitis is a serious but uncommon condition which presents considerable difficulties in recognition, diagnosis and treatment. We studied eight consecutive patients in whom this diagnosis was made. Despite the great diversity of symptoms and signs, we noted three clinical patterns: (i) acute or sub-acute encephalopathy, (ii) a picture with some similarities to multiple sclerosis ('MS-plus'), and (iii) features of a rapidly progressive space-occupying lesion. The identification of these patterns may help recognition of cerebral vasculitis. The diagnostic value of four investigative procedures not previously studied in cerebral vasculitis was assessed: ophthalmological examination using low-dose fluorescein angiography with slit-lamp video microscopy of the anterior segment (abnormal in 4/5 patients); spinal fluid oligoclonal band analysis (abnormal in 3/6 patients); anti-neutrophil cytoplasmic antibody assay (abnormal in 3/8 patients); and indium-labelled white-cell cerebral imaging (positive in only one patient). Treatment was with steroid alone (n = 2) or steroid with cyclophosphamide (n = 6). Seven patients responded clinically.

beta-Interferon regulates the immunomodulatory activity of neonatal rodent microglia

beta-interferon (beta-IFN) has both pro and anti-inflammatory properties, the balance of which leads to some suppression of disease activity in multiple sclerosis patients. Here, we examine the immunomodulation of neonatal rodent microglia, the principal CNS accessory cell, by beta-IFN and consider the interaction of beta-IFN and gamma-interferon (gamma-IFN). beta-IFN and gamma-IFN inhibit microglial proliferation. beta-IFN antagonises both gamma-IFN-induced upregulation of class II expression and the ability of gamma-IFN primed cells to mount a respiratory burst. In contrast, beta-IFN upregulates microglial Fc receptor expression and augments tumour necrosis factor alpha secretion from suboptimally stimulated microglia.

Wolfram syndrome: hereditary diabetes mellitus with brainstem and optic atrophy

Wolfram syndrome was originally described as a combination of familial juvenile-onset diabetes mellitus and optic atrophy. Other neurological features subsequently emerged, and "DIDMOAD" (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness) became a commonly accepted acronym. Here, we describe 4 further cases from 2 families, in whom there occurred previously unrecognized neurological features, central apnea and neurogenic upper airway collapse, together precipitating primary respiratory failure (fatal in 1 case), startle myoclonus (in 2 unrelated cases), axial rigidity, and Parinaud's syndrome. Magnetic resonance images revealed striking brainstem atrophy affecting, in particular, the pons and midbrain. The mitochondrial DNA from 3 cases (and relatives) showed no evidence of any of the previously reported abnormalities. These neurological and neuroradiological features, in conjunction with (1) analyses showing the neurodegenerative origin of optic atrophy, deafness, diabetes insipidus, and incontinence, (2) other previously reported neurological complications (including anosmia, ataxia, epilepsy, and neuropsychiatric and cognitive abnormalities), and (3) the very small number of published postmortem studies, indicate that Wolfram syndrome should be reemphasized as a unique hereditary neurodegenerative disorder with prominent optic atrophy and diabetes mellitus.

Auctioneer's jaw: a case of occupational oromandibular hemidystonia

An auctioneer is described in whom focal dystonia of the jaw developed as an occupational symptom, occurring solely and predictably when he commenced his selling "patter" and resolving quickly on stopping. He responded well to treatment with intramuscular botulinus toxin.

A proliferative adult human oligodendrocyte progenitor

The failure of oligodendrocytes to sustain repair of demyelinated axons contributes to the cumulative neurological disability which characterizes multiple sclerosis. In the rodent, transplanted neonatal glial progenitors efficiently remyelinate gliotoxic lesions. Proliferative bipotential progenitors are also present in the adult rat, but have not hitherto been identified in adult human tissue. Here we demonstrate cells in cultures of adult human temporal lobe which are morphologically and immunocytochemically identical to rate progenitors, are bipotential, and exhibit an astrocyte-driven proliferative response. The identification of an adult human oligodendrocyte progenitor is the first step towards developing interventional strategies for promoting repair of demyelinated lesions in patients with multiple sclerosis.