Shunsei Hirohata

Association of cerebrospinal fluid anti-NR2 glutamate receptor antibodies with diffuse neuropsychiatric systemic lupus erythematosus

OBJECTIVE To explore the association of antibodies directed against N-methyl-D-aspartate receptor subunit NR2 (anti-NR2) in cerebrospinal fluid (CSF) with neuropsychiatric manifestations in systemic lupus erythematosus (NPSLE). METHODS Paired serum and CSF specimens were obtained from 56 patients with NPSLE (38 with diffuse psychiatric/neuropsychological syndromes [diffuse NPSLE] and 18 with neurologic syndromes or peripheral neuropathy [focal NPSLE]) and from 20 control patients with noninflammatory neurologic diseases. IgG anti-NR2 antibodies were measured by enzyme-linked immunosorbent assay using synthetic peptide containing the extracellular ligand-binding domain of NR2. The binding of affinity-purified anti-NR2 to human neuroblastoma cell line SK-N-MC was examined by flow cytometry. RESULTS Purified anti-NR2 bound to the surface of SK-N-MC cells. Levels of anti-NR2 antibodies in CSF were significantly elevated in patients with diffuse NPSLE compared with levels in control patients or those with focal NPSLE, whereas there were no significant differences in serum anti-NR2 levels among the 3 groups. In 31 of the 38 patients with diffuse NPSLE (81.6%) and 8 of the 18 patients with focal NPSLE (44.4%), CSF anti-NR2 levels were more than 3 SD above the mean level in the control patients (P=0.0120 by chi-square test). CONCLUSION These results indicate that anti-NR2 is a constituent of antineuronal antibodies and, more importantly, that anti-NR2 antibodies in CSF, but not in serum, are associated with diffuse NPSLE.

Differential roles of the anti-ribosomal P antibody and antineuronal antibody in the pathogenesis of central nervous system involvement in systemic lupus erythematosus

OBJECTIVE To compare the role of antibodies against the ribosomal P protein (anti-P) with that of antibodies against neuronal cells (anti-N) in the pathogenesis of central nervous system (CNS) involvement in systemic lupus erythematosus (SLE). METHODS Sera from 87 SLE patients (27 with non-CNS SLE, 34 with lupus psychosis, and 26 with nonpsychotic CNS lupus) and from 20 control patients with neurologic manifestations without SLE and cerebrospinal fluid (CSF) from 41 patients with CNS lupus and from the 20 control patients were assayed for IgG anti-P and anti-N by an enzyme-linked immunosorbent assay (ELISA) using ribosomal P synthetic peptides and by a cell ELISA using paraformaldehyde-fixed SK-N-MC neuroblastoma cell lines, respectively. RESULTS Serum anti-P levels were significantly elevated in patients with lupus psychosis compared with those with non-CNS SLE or those with nonpsychotic CNS lupus, whereas there were no significant differences in serum anti-N levels among these 3 groups. In contrast, CSF anti-N levels were significantly elevated in patients with lupus psychosis compared with those with nonpsychotic CNS lupus and compared with non-SLE controls, whereas CSF anti-P were not detected in most of the patients. CONCLUSION The results indicate that anti-P in the systemic circulation and anti-N in the CSF are involved in the development of lupus psychosis.

Low-dose weekly methotrexate for progressive neuropsychiatric manifestations in Behcet's disease

The most serious central nervous system (CNS) manifestation in Behcets disease is a slowly progressive dementia (progressive NB), which may ultimately lead to the deterioration of the personality of patients. An open trial was designed to investigate the efficacy of low dose weekly methotrexate (MTX) therapy for progressive NB. Six patients with Behcets disease, whose neuropsychiatric manifestations were judged to be progressive (4 females and 2 males, aged 55.0+/-8.2 years), were given oral MTX (7.5-12.5 mg/week) until the end of the 12-month trial. The clinical responses of the patients to MTX were judged by neuropsychiatric findings, intelligence test, brain MRI scans and cerebrospinal fluid (CSF) IL-6 levels. After the 12-month trial, CSF IL-6 levels were found to be significantly decreased. Accordingly, the neuropsychological manifestations as well as the findings on MRI scans and intelligence quotients were not significantly worsened after the trial. Three patients presented with mild liver dysfunction, which returned to normal by decreasing the dose of MTX. However, 6 months after discontinuation of MTX, all the six patients showed significant exacerbation of the manifestations as evidenced by a decrease in verbal intelligence quotients along with the marked elevation of CSF IL-6. These results suggest that low dose weekly MTX therapy might have a beneficial effect in the treatment of progressive NB, although a trial for a longer period would be necessary.

Histopathology of central nervous system lesions in Behçet's disease

Central nervous system (CNS) involvement in Behçets disease, usually called neuro-Behçets syndrome (NB), is one of the most serious complications of the disease. In the present study, we carried out immunohistological examination of biopsied or autopsied brain tissues from 3 patients with different types of NB, acute NB, chronic progressive NB, and NB in a long-term remission. Histopathology of mass lesion in acute NB revealed infiltration of mononuclear cells around small vessels, consisting of CD45RO+ T lymphocytes and CD68+ monocytes with few CD20+ B lymphocytes. Of interest, TUNNEL staining disclosed that most neurons were undergoing apoptosis in the inflammatory lesion. In chronic progressive NB, similar histopathological changes were noted in pons, cerebellum, medulla, internal capsule, and midbrain, although the degree of mononuclear cell infiltration was modest. There were also scattered foci of neurons undergoing apoptosis with formation of a few binucleated neurons. The most prominent feature of NB in a long-term remission was atrophy of basal pons with formation of cystic or moth-eaten lesions, consisting of isomorphic gliosis with viable neurons. There were still scattered foci of perivascular cuffing of T lymphocytes and monocytes. These results emphasize the common features throughout the courses of NB, perivascular cuffing of T lymphocytes and monocytes, irrespective of the clinical phenotypes. More importantly, it is suggested that soluble factors produced by infiltrating cells, including IL-6, might play a role in the induction of apoptosis of neurons in NB.

Streptococcal-related antigens stimulate production of IL6 and interferon-γ by T cells from patients with Behcet's disease

Greater attention has been recently paid to the role of certain strains of streptococcus as an etiologic agent of Behçets disease, in which T cell abnormalities are considered to be involved. We therefore examined whether T cells from patients with Behçets disease might to be stimulated by Streptococcus sanguis-related antigen (RRE KTH-1 antigens). T cells from 17 patients with Behcets disease, but not those from 13 healthy individuals or from 13 patients with other rheumatic diseases, were stimulated to produce greater amounts of interleukin 6 (IL6) by addition of RRE KTH-1 antigens [stimulation index: 3.96 +/- 0.56 and 1.35 +/- 0.28 or 1.83 +/- 0.43 (mean +/- SEM), respectively]. The IL6 production by T cells required the presence of either fresh or paraformaldehyde-fixed monocytes. The enhancement of T cell IL6 production was not related to the presence of HLA-B51, which has been shown to be frequently associated with Behçets disease. These results indicate that T cells from patients with Behçets disease are stimulated by streptococcal antigens to produce IL6 through T cell-monocyte interactions in which binding of the antigens to monocytes, but not necessarily processing of the antigens by monocytes, is involved. Moreover, RRE KTH-1 antigens as well as Escherichia coli-derived antigens also enhanced the production of interferon-gamma by T cells from patients with Behçets disease. The data thus suggest that T cell hypersensitivity to several bacterial antigens may play a central role in the pathogenesis of Behçets disease.

Effect of infliximab in progressive Neuro-Behçet's syndrome

Recent studies have shown the beneficial effect of infliximab in ocular manifestation of Behçets disease. The current studies examined the efficacy of infliximab in progressive neuro-Behçets syndrome (NB) refractory to methotrexate (MTX). Five male patients with progressive NB with sustained elevation of cerebrospinal fluid (CSF) IL-6 (over 20 pg/ml) despite administration of MTX and steroid, were given intravenous infusion of 5 mg/kg infliximab at weeks 0, 2, 6, and 14 with MTX (10-17.5 mg/week) and prednisolone (<10 mg/day) at the same doses. The clinical responses were judged by neuropsychiatric findings, revised Wechsler adult intelligence scale (WAIS-R), and brain magnetic resonance imaging (MRI) scans at 24 weeks. In all the 5 patients, CSF IL-6 were markedly decreased by 1/2-1/37 on the next day of the first infusion and remained below 20 pg/ml before the last infusion at 14 weeks, whereas CSF TNF-alpha were not significantly changed at any time point. At 24 weeks from the initial infusion, none of the 5 patients showed exacerbation (3 patients significantly improved). Nor did the atrophy in midbrain, pons and medulla on brain MRI scans show significant progression. These results suggest that infliximab might have a beneficial effect in the treatment of progressive NB by reducing CSF IL-6 levels but not TNF-alpha. Since infliximab has been shown to have cytotoxic effects on monocytes/macrophages, the rapid fall of CSF IL-6 after the infusion suggest that infliximab might directly act on such inflammatory cells producing IL-6.

Efficacy of Rebamipide as Adjunctive Therapy in the Treatment of Recurrent Oral Aphthous Ulcers in Patients with Behçet’s Disease

AbstractBackground: Behçet’s disease (BD) is a recurrent inflammatory disease involving chronic recurrent oral aphthous ulcers (aphthae), uveitis, skin lesions and genital ulcers. We prospectively investigated the efficacy of rebamipide, a gastroprotective drug, against oral aphthous ulcers in BD patients. Methods: In a multicentre, double-blind, placebo-controlled study, 35 patients with BD, having as the main symptom oral aphthosis, were randomised to receive rebamipide 300 mg/day or placebo for 12 to 24 weeks between August 1994 and December 1996. Oral aphthosis must have occurred within 4 weeks prior to enrolment and must have been visible for at least 7 days during that time. Oral aphthae count and pain scores were recorded daily in a diary by the patients themselves. Monthly aphthae count and pain scores were defined as the sum of aphthae count and pain scores for a month, respectively. Investigators rated the global improvement in aphthae count and pain using a 6-point scale. The rate of change in monthly aphthae count and pain scores in the first 3 and last 3 months of treatment were assessed in patients with more severe symptoms whose aphthae count and pain score were >28 at baseline (trial entry). Results: The rate of moderate or marked improvement in aphthae count and pain was 36% (5 of 14 subjects) in the placebo group and 65% (11 of 17 subjects) in the rebamipide group. During months 2 to 6 of treatment, aphthae count tended to increase and reached a peak at month 4 in the placebo group but decreased in the rebamipide group. Pain score decreased to the same extent in both groups for the first 3 months of treatment; however, in the fourth to sixth months of treatment, the pain score tended to increase in the placebo group but decreased in the rebamipide group. In patients with a monthly aphthae pain score >28 at baseline, pain and count scores decreased throughout the 6 months of rebamipide treatment but increased during the last 3 months of treatment in the placebo group (p < 0.01 for the between-group comparisons). Conclusions: Rebamipide is well tolerated and improves the aphthae count and pain score in BD patients. It may therefore be useful in the treatment and prevention of frequently recurrent oral aphthous ulcers (not restricted to BD). Administration of rebamipide is not cumbersome, and it does not cause any discomfort, which corticosteroid ointments for example may do; furthermore, there are no specific adverse drug reactions. Rebamipide is therefore recommended as a long-term treatment for recurrent oral aphthous ulcers.

IgG anti-NR2 glutamate receptor autoantibodies from patients with systemic lupus erythematosus activate endothelial cells.

OBJECTIVE To investigate the possibility that IgG anti-NR2 glutamate receptor antibodies (anti-NR2) derived from patients with systemic lupus erythematosus (SLE) cause an immunologic interaction with endothelial cells (ECs) in the blood-brain barrier, resulting in inflammation of the blood-brain barrier, allowing the entrance of these autoantibodies into the cerebrospinal fluid. METHODS Purified IgG anti-NR2 antibodies from 14 patients with SLE were tested for their ability to bind to double-stranded DNA (dsDNA) and ECs, to modulate endothelial adhesion molecule expression and cytokine production by ECs, and to activate the NF-κB pathways in the ECs. Purified IgG from 5 normal subjects was used as a negative control. RESULTS Purified IgG anti-NR2 antibodies bound to dsDNA in an IgG-dose-dependent manner. This interaction up-regulated the expression of endothelial leukocyte adhesion molecule 1, vascular cell adhesion molecule 1, and intercellular adhesion molecule 1 on the EC surface and increased the production of interleukin-6 (IL-6) and IL-8, but not tumor necrosis factor α or IL-1β, by ECs. Purified IgG anti-NR2 also activated the degradation of cytoplasmic IκB, indicating the activation of NF-κB in the ECs. CONCLUSION EC activation through the NF-κB signaling pathway induced by IgG anti-NR2 antibodies in the central nervous system of SLE patients may lead to inflammation of the blood-brain barrier, initiating the pathogenesis of neuropsychiatric SLE.

Clinical characteristics of cytomegalovirus infection in rheumatic diseases: multicentre survey in a large patient population

OBJECTIVE To survey and elucidate the clinical characteristics of CMV infection in rheumatic disease patients. METHODS A detailed questionnaire survey on CMV infection was carried out against rheumatic disease patients hospitalized in member hospitals, and the obtained clinical and/or laboratory data were analysed. RESULTS Out of 7377 patients, 151 were diagnosed as having CMV infection. The underlying diseases ranged broadly, but SLE, microscopic polyangiitis, and dermatomyositis were the most common. Four were diagnosed histopathologically, and the others via positive CMV antigenaemia. In addition to oral corticosteroid for all but one patient, 81 were treated with pulsed methylprednisolone (MPSL), 64 with cyclophosphamide (CYC) and 36 with other immunosuppressants. Forty-four had a fatal outcome, for which presence of clinical symptoms, other infectious complications, lymphopenia, an older age (>59.3 yrs) and the use of pulsed MPSL were significant risk factors (P < 0.05) by univariate analysis. Multivariate analysis retained the first three (P < 0.05). The CMV antigenaemia count was significantly higher for the symptomatic than asymptomatic [10.1 (0.0-2998.0) vs 4.0 (1.3-1144.4)/10(5) PMNs, respectively, P < 0.05; threshold count: 5.6/10(5) PMNs]. No treatment benefit by anti-viral agent was observed as for survival. CONCLUSION CMV infection was mostly diagnosed by antigenaemia, and occurred among patients under strong immunosuppressive therapy using pulsed MPSL and/or immunosuppressants. Lymphopenia, presence of symptoms and other infections are significant risk factors for a poor outcome and pulsed MPSL and an older age may predict it. Patients were prone to be symptomatic with anti-genaemia count over 5.6/10(5) PMNs.

Angioneogenesis as a possible elusive triggering factor in rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic inflammatory disease characterised by a progressive destruction of joints. T h e hallmarks of the pathological changes in the synovium include hyperplasia of synovial lining cells and follicle-like aggregation of lymphocytes and plasma cells. It has been appreciated that the empirical use of antirheumatic drugs earlier in the disease results in the improvement of the prognosis for many RA patients. It is therefore important to delineate the earliest pathological changes of the rheumatoid synovium to identify the primary targets of therapeutic i n t e r v e n t i o n . Although previous studies identified capillary damage, oedema, vascular congestion, cellular infiltrates as earlier pathological changes in the rheumatoid synovium, , 2