[A case of anti-PL7 antibody positive myositis and a clinical and pathological review of the anti-synthetase syndrome].

A 52-year-old woman was admitted to our hospital with muscle pain and an elevated creatine kinase level. She had experienced wrist pain at onset seven years ago. The initial possible diagnoses were rheumatoid arthritis and adult-onset Still disease. The patient received corticosteroid and immunosuppressant therapy but experienced deterioration of symptoms. The symptoms of muscle pain and mild creatine kinase elevation emerged four years prior to her visit. Further elevation of creatine kinase was observed for three months before her visit despite adjusting the immunosuppressant dose. On admission, she presented with muscle moderate weakness of the trunk and extremities and pain of the shoulder and medial thigh muscles. Elevation of muscle enzymes and inflammatory response were also detected, and the anti-PL7 antibody was positive. Muscle biopsy from biceps brachii revealed necrotizing myopathy with necrotic and regenerated muscle fibers. The final diagnosis was anti-PL7 antibody positive myositis. The patient was treated with a higher dose of prednisolone and an adequate dose of tacrolimus. Following this treatment, the symptoms were improved. Anti-ARS (aminoacyl t-RNA synthetase) antibodies such as anti-PL7 antibody are useful in diagnosis and for prognostic prediction. Further investigation of patients with anti-ARS antibodies positive myositis is required.

Usefulness of 11C-methionine-positron emission tomography for the diagnosis of progressive multifocal leukoencephalopathy.

Progressive multifocal leukoencephalopathy (PML) is a subacute demyelinating disease of the brain caused by the JC virus that occurs mainly in immunocompromised patients. The prognosis is very poor. As the lesion looks like non- specific leukoencephalopathy, making a diagnosis at the early stage is very difficult. We report three PML cases in which there was a mismatch between (11)C-methionine-positron emission tomography (MET-PET) uptake and (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) uptake. All three cases demonstrated the hyper-uptake of MET around the white matter lesions and hypo-uptake of FDG inside the lesions. We speculate that the infection had ended inside the white matter lesions of these patients, while JC virus infection was ongoing around the lesions, resulting in the increase of methionine metabolism, and the glucose metabolism was reduced or intermediate because inflammatory cells infiltrate PML lesions rarely. Two patients who were diagnosed and treated with mefloquine while the JC virus was at a low level in the cerebrospinal fluid are still alive. We suggest the usefulness of MET-PET for the early diagnosis of PML and early treatment with mefloquine.

Novel GNE compound heterozygous mutations in a GNE myopathy patient.

INTRODUCTION: Molecular studies have revealed that some patients with myopathies with rimmed vacuoles have pathogenic mutations in the UDP-N-acetylglucosamine-2-epimerase/N-acetylmannosamine kinase (GNE) and Z-band alternatively spliced PDZ motif-containing protein (ZASP) genes. METHODS: We investigated a patient with distal myopathy with rimmed vacuoles by muscle biopsy and sequenced 6 candidate genes. RESULTS: The patient carried GNE compound heterozygous missense mutations (p.V421A and p.N635K) and a ZASP variant (p.D673N). This patient also presented with distal weakness sparing the quadriceps muscles and had atypical results for Z-band-associated protein immunostaining. This finding indicates that the GNE mutations are pathogenic, and the diagnosis is compatible with GNE myopathy. CONCLUSIONS: By combining pathological studies and candidate gene screening, we identified a patient with GNE myopathy due to novel GNE compound heterozygous mutations.

Estrogens as potential therapeutic agents in multiple sclerosis.

The disease activity of multiple sclerosis (MS) is known to be ameliorated during pregnancy, and pregnancy is also found to be protective in experimental autoimmune encephalomyelitis (EAE), an animal model of MS. Estrogen levels increase during pregnancy and basic researches have shown that estrogens have immunomodulatory effects on immune cells. The importance of estrogen in pathogenic autoimmune diseases has also been demonstrated in EAE by altering hormone levels. Mice treated with estrogen experienced significantly decreased EAE severity and delayed onset of disease as a result of neuroprotective and anti-inflammatory effects. Brain atrophy has been detected at the early stages of MS by using MRI; thus, as a neuroprotective agent, estrogen might be effective against brain atrophy. Estrogen's effects are primarily mediated by the nuclear estrogen receptor (ER), and recent studies have shown the presence of nuclear ERs on the cells involved in the immune response. There have been some reports on genetic polymorphisms of ERs in MS. In this review paper, we discuss increasing evidence that points to a link between estrogen and MS. We also analyze the therapeutic potential of estrogens in MS and review current genetic studies on ER.

Memory and naïve B-cell subsets in patients with multiple sclerosis.

Memory and naïve B cells are considered to play distinct roles in immune regulation. However, the roles of memory and naïve B-cell subsets in multiple sclerosis (MS) have not yet been elucidated. In this study, we examined whether memory and naïve B-cell subsets differ between patients with MS and healthy subjects and whether interferon beta (IFNbeta)-1b can affect these subsets in patients with MS. We also studied these subsets in relapsing and remitting stages of MS. Subjects included 31 patients with relapsing-remitting MS in the remitting stage, of which 15 were treated with IFNbeta-1b and 16 were not treated, and 22 healthy control subjects. For 11 of the 16 untreated patients, blood samples were also obtained in the relapsing stage. Expression of CD5, CD80, CD86, CCR5, CXCR3, CD11a, and CD49d in memory and naïve B cells in blood samples was examined by flow cytometry. The percentages of CD86(+) cells and CCR5(+) cells in the naïve B-cell subset were significantly higher in untreated patients than in control subjects or IFNbeta-treated patients. In patients with MS, the percentages of CD86(+) cells and CCR5(+) cells in the naïve B-cell subset and the percentage of CD5(+) cells in the memory B-cell subset were significantly greater in the remitting stage than in the relapsing stage. These results indicate that memory and naïve B-cell subsets, especially CD86(+) naïve B cells, CCR5(+) naïve B cells, and CD5(+) memory B cells, might be useful in the study of the pathogenesis of and therapy for MS.