Paul M. Candler

Neuronal surface glycolytic enzymes are autoantigen targets in post-streptococcal autoimmune CNS disease

Infection with the Group A Streptococcus (GAS) can result in immune mediated brain disease characterised by a spectrum of movement and psychiatric disorders. We have previously described anti-neuronal antibodies in patients that bind to a restricted group of brain antigens with molecular weights 40 kDa, 45 kDa (doublet) and 60 kDa. The aim of this study was to define these antigens using 2-dimensional electrophoresis or ion exchange and hydrophobic interaction chromatography, followed by mass spectrometry. The findings were confirmed using commercial antibodies, commercial antigens and recombinant human antigens. The autoantigens were neuronal glycolytic enzymes--NGE (pyruvate kinase M1, aldolase C, neuronal-specific and non-neuronal enolase). These are multifunctional proteins that are all expressed intracellularly and on the neuronal cell surface. On the neuronal plasma membrane, NGE are involved in energy metabolism, cell signalling and synaptic neurotransmission. Anti-NGE antibodies were more common in the 20 unselected post-streptococcal CNS patients compared to 20 controls. In vitro experiments using cultured neurons showed that commercial anti-NGE antibodies induced apoptosis compared to blank incubation and control anti-HuD antibody. GAS also expresses glycolytic enzymes on cell surfaces that have 0-49% identity with human NGE, suggesting molecular mimicry and autoimmune cross-reactivity may be the pathogenic mechanism in post-streptococcal CNS disease.

A follow up study of patients with paraneoplastic neurological disease in the United Kingdom

Objectives: To examine the range of clinical phenotypes, tumour associations, relevant investigations, response to therapy and outcome in a large series of non-selected patients with paraneoplastic neurological disease (PND) affecting the central nervous system (CNS) in the United Kingdom. Methods: Data were obtained on patients either through direct referral or through the British Neurological Surveillance Unit (BNSU) from February 2000 to January 2001. Physicians were asked to supply information about age and sex of patients, presenting neurological syndromes, the basis of the diagnosis of PND, any associated malignancy, and treatment. Case notes were reviewed and follow up data obtained where possible one year after notification. Results: A total of 63 patients (48 females, 15 males) were identified, 48 through the BNSU and 15 through direct referral. Of these 52 were diagnosed as having definite PND, 10 probable PND, and 1 possible PND. The median age of onset of PND was 66 years (range 30–80 years) and only 7 patients (11%) were less than 50 years at presentation. In 53 patients (84%) the PND preceded the diagnosis of cancer. Paraneoplastic sensory neuronopathy, paraneoplastic encephalomyelitis, and paraneoplastic cerebellar degeneration (PCD) were the most common syndromes reported. The benefit of magnetic resonance imaging in the diagnosis of the disease was limited, while fluorodeoxyglucose positron emission tomography was shown to be useful for the detection of an occult malignancy in 10 out of 14 patients. Antineuronal antibodies were positive in 44/57 (77%) of cases. The following tumours were diagnosed: small cell lung cancer (30%), breast cancer (14%), ovarian cancer (8%), non-small cell lung cancer (8%), Hodgkin’s lymphoma (6%), other (16%). With the exception of PCD associated with mesothelioma all other tumours diagnosed in these patients had been previously documented as being associated with PND. Only treatment of the tumour was found to be associated with a stable or improved neurological outcome at last follow up (Fisher‘s exact test = 4.7, p<0.03). Median survival time was 43 months (95% CI 28 to 57) from onset of neurological disease as calculated using the Kaplan–Meier survival analysis. Conclusions: PND has a striking female preponderance usually affecting patients in their sixth decade and above. The median survival in our study was 43 months. The majority of patients with PND are not known to have cancer at the time of diagnosis. Our study confirms the importance of diagnosing and treating the underlying tumour.

CSF and serum immune parameters in Sydenham's chorea: evidence of an autoimmune syndrome?

Previous investigations have suggested that Sydenhams chorea (SC) may be an autoantibody mediated disorder. We examined this autoimmune hypothesis by measuring Th1 (IFN-gamma, IL-12) and Th2 (IL-4, IL-10) cytokines, oligoclonal bands (OCB) and anti-basal ganglia antibodies (ABGA). CSF IL-4 was elevated in 31% of acute SC and 50% of persistent SC. CSF IL-10 was also elevated in 31% of acute SC but 0% of persistent SC. CSF IFN-gamma was undetectable in all patients. Serums IL-4, IL-10 and IL-12 were elevated in acute compared to persistent SC. OCB were found in 46% of acute SC, ABGA were in 93% of acute SC and 50% of persistent SC was of IgG(1) and IgG(3) subclass. These findings support an autoantibody pathogenesis.

Post-streptococcal opsoclonus-myoclonus syndrome associated with anti-neuroleukin antibodies

Background: Adult opsoclonus-myoclonus (OM), a disorder of eye movements accompanied by myoclonus affecting the trunk, limbs, or head, is commonly associated with an underlying malignancy or precipitated by viral infection. Methods: We present the first two reports of post-streptococcal OM associated with antibodies against a 56 kDa protein. Two young girls presented with opsoclonus and myoclonus following a febrile illness and pharyngitis. Protein purification techniques were employed. Amino acid sequences of human neuroleukin (NLK) and streptococcal proteins were compared using the protein-protein BLAST application. Results: The antigen was identified as NLK (glucose-6-phosphate isomerase, GPI). GPI is present on the cell surface of streptococcus making the protein a candidate target for molecular mimicry. Conclusions: We have identified NLK as an antigenic target in two patients with post-streptococcal OM. The pathogenicity of the antibodies is uncertain. The potential role of anti-neuroleukin antibodies in the pathogenesis of OM is discussed. We propose that OM may represent a further syndrome in the growing spectrum of post-streptococcal neurological disorders. The role of streptococcus in OM and the frequency with which anti-NLK responses occur in both post-infectious and paraneoplastic OM should be investigated further.

Antineuronal antibodies in Parkinson's disease.

Antineuronal antibodies (ANAs) have been implicated in the pathophysiology of postinfectious movement disorders, such as Sydenhams chorea. However, their relevance in other movement disorders—in the absence of infectious triggers—remains much disputed. We sought to assess the frequency of ANAs in idiopathic Parkinsons disease (IPD) and to explore whether a specific phenotype is associated with the presence of ANAs. For this purpose, we recruited 76 IPD patients, 9 patients with genetic parkinsonism, and 10 with one of the parkinson‐plus syndromes. They were all subjected to a comprehensive clinical review. In addition, 50 patients with non‐extrapyramidal neurological disease and 30 healthy blood donors served as control populations. Blood samples were tested for the presence of ANAs with Western blotting, using recombinant proteins of the three putative antigens (aldolase C, neuron‐specific enolase, and pyruvate kinase M1). We found these antibodies in 11.8% of the 76 IPD patients, which differed significantly from healthy controls (0%, P = 0.043), but nonsignificantly from patients with genetic parkinsonism (11.1%), with a parkinson‐plus syndrome (10%), or from neurological disease controls (4%). With respect to relevant disease characteristics, IPD patients with or without ANAs were indistinguishable, except for atypical disease features (mainly early falls or freezing and marked Pisa syndrome), which were more frequent in the ANA‐positive IPD group. We conclude that ANAs do not play a role in the majority of patients with IPD, but might be relevant in the pathogenesis of IPD with atypical features.

Lack of Serum Oligoclonal Antibody Responses to Chlamydophila pneumoniae in Multiple Sclerosis

Chlamydophila pneumoniae has been proposed as an aetiological agent in MS via a mechanism involving molecular mimicry. We undertook to investigate whether the presence of CSF oligoclonal IgG OCB or oligoclonal bands correlated with serum IgG raised against C. pneumoniae. Paired serum and CSF of 19 MS patients and 27 control patients with other neurological diseases were studied by IEF and Western blotting. Only 1 of 19 MS patients had serum antibodies against C. pneumoniae compared with 2 of the 26 control patients. This was not significant, leading us to conclude that this study does not support the theory of an association between C. pneumoniae and MS.

Quantitative demonstration of intrathecal synthesis of high affinity immunoglobulin G in herpes simplex encephalitis using affinity-mediated immunoblotting

Three paired serial samples of CSF and serum (from days 8, 13 and 22) were taken from a patient referred to the National Hospital for Neurology and Neurosurgery with what was duly confirmed as having herpes simplex encephalitis using PCR. The samples were investigated using affinity-mediated immunoblotting followed by incubation with sodium thiocyanate. Digitisation of the blots enabled further analysis. We showed that the clones of antigen-specific IgG, which were produced intrathecally, were of higher relative affinity than polyclonal antigen-specific IgG.