JOURNAL OF NEUROINFLAMMATION

A novel autoantibody against ephrin type B receptor 2 in acute necrotizing encephalopath

An Innovative Method to Identify Autoantigens Expressed on the Endothelial Cell Surface: Serological Identification System for Autoantigens Using a Retroviral Vector and Flow Cytometry (SARF)

Autoantibodies against integral membrane proteins are usually pathogenic. Although anti-endothelial cell antibodies (AECAs) are considered to be critical, especially for vascular lesions in collagen diseases, most molecules identified as autoantigens for AECAs are localized within the cell and not expressed on the cell surface. For identification of autoantigens, proteomics and expression library analyses have been performed for many years with some success. To specifically target cell-surface molecules in identification of autoantigens, we constructed a serological identification system for autoantigens using a retroviral vector and flow cytometry (SARF). Here, we present an overview of recent research in AECAs and their target molecules and discuss the principle and the application of SARF. Using SARF, we successfully identified three different membrane proteins: fibronectin leucine-rich transmembrane protein 2 (FLRT2) from patients with systemic lupus erythematosus (SLE), intercellular adhesion molecule 1 (ICAM-1) from a patient with rheumatoid arthritis, and Pk (Gb3/CD77) from an SLE patient with hemolytic anemia, as targets for AECAs. SARF is useful for specific identification of autoantigens expressed on the cell surface, and identification of such interactions of the cell-surface autoantigens and pathogenic autoantibodies may enable the development of more specific intervention strategies in autoimmune diseases

Clinical efficacy of tocilizumab in patients with active rheumatoid arthritis in real clinical practice

The previous clinical studies have demonstrated tocilizumab monotherapy to be highly effective in rheumatoid arthritis (RA). The objectives of the present article are to report the efficacy and safety of tocilizumab in patients with active RA in real clinical practice. In total, 61 patients with RA were treated with tocilizumab. Any comorbidities they had, especially infections, were treated thoroughly before they were given the drug. We provided guidance on infection control and prevention. Mean age of the patients was 60.9 ± 12.4 years, and their mean disease duration 10.9 ± 9.2 years. The patients remained on steroids, methotrexate, and tacrolimus as before, but were taken off any other drugs they had been using prior to the treatment. Mean of the 28-joint disease activity score using erythrocyte sedimentation rate was 4.75 ± 1.15 initially and fell to 2.21 ± 0.97 after two doses (n = 50). After four doses, the remission rate was 83.8% (31/37). All patients responded well to the therapy and there was no decrease in the efficacy of tocilizumab during the treatment. Even in the real clinical setting, treatment with tocilizumab can rapidly induce remission in RA in a high proportion of patients and is generally safe and well tolerated. Tocilizumab would seem to be promising as a first-line choice for the treatment of RA

Iron-heme-Bach1 axis is involved in erythroblast adaptation to iron deficiency

Iron plays the central role in oxygen transport by erythrocytes as a constituent of heme and hemoglobin. The importance of iron and heme is also to be found in their regulatory roles during erythroblast maturation. The transcription factor Bach1 may be involved in their regulatory roles since it is deactivated by direct binding of heme. To address whether Bach1 is involved in the responses of erythroblasts to iron status, low iron conditions that induced severe iron deficiency in mice were established. Under iron deficiency, extensive gene expression changes and mitophagy disorder were induced during maturation of erythroblasts. Bach1−/− mice showed more severe iron deficiency anemia in the developmental phase of mice and a retarded recovery once iron was replenished when compared with wild-type mice. In the absence of Bach1, the expression of globin genes and Hmox1 (encoding heme oxygenase-1) was de-repressed in erythroblasts under iron deficiency, suggesting that Bach1 represses these genes in erythroblasts under iron deficiency to balance the levels of heme and globin. Moreover, an increase in genome-wide DNA methylation was observed in erythroblasts of Bach1−/− mice under iron deficiency. These findings reveal the principle role of iron as a regulator of gene expression in erythroblast maturation and suggest that the iron-heme-Bach1 axis is important for a proper adaptation of erythroblast to iron deficiency to avoid toxic aggregates of non-heme globin