No abstract

The membrane TNF-α is known to serve as a precursor of the soluble form of TNF-α. Although it has been reported the biological functions of the membrane TNF-α as a ligand, the outside-to-inside (reverse) signal transmitted through membrane TNF-α is poorly understood. Here we report a novel function mediated by outside-to-inside signal via membrane TNF-α into the cells expressing membrane TNF-α. Activation by anti-TNF-α Ab against membrane TNF-α on human T cell leukemia virus (HTLV) I-infected T cell line, MT-2, or PHA-activated normal human CD4+ T cells resulted in the induction of an adhesion molecule, E-selectin (CD62E), on the cells with the peak of 12–24 h, which completely disappeared by 48 h. When wild-type or mutant membrane TNF-α (R78T/S79T) resistant to proteolytic cleavage was introduced into Jurkat or HeLa cells, E-selectin was induced by the treatment with anti-TNF-α Ab with the similar kinetics. Membrane TNF-α-expressing Jurkat cells also up-regulated E-selectin when brought into cell-to-cell contact with TNF receptor-expressing HeLa cells. Northern blot analysis and RT-PCR analysis showed that the membrane TNF-α-mediated E-selectin expression was up-regulated at the level of transcription. These results not only confirmed our previous findings of reverse signaling through membrane TNF-α, but also presented evidence that E-selectin was inducible in cell types different from endothelial cells. It is strongly suggested that membrane TNF-α is a novel proinflammatory cell surface molecule that transmits bipolar signals in local inflammation.

We studied the clinico-pathological differences among PR3-ANCA-positive granulomatosis with polyangiitis (PR3-GPA), MPO-ANCA-positive GPA (MPO-GPA) and microscopic polyangiitis (MPA). ANCA-associated vasculitis (AAV) was classified using the European Medicines Agency classification. We retrospectively analyzed 38 patients with GPA and 41 with MPA treated in eight hospitals in Japan. Of the patients with GPA, 17 were positive for MPO-ANCA, and 15 for PR3-ANCA. All patients with MPA were MPO-ANCA positive. The mean ages of those with MPO-GPA were 69.6 years old, 10 years older than those with PR3-GPA. The majority (82 %) of patients with MPO-GPA were woman, a significantly greater proportion than for PR3-GPA. We also found that ear, nose and throat (ENT), nervous system involvement were significantly more common in MPO-GPA, but renal function was less impaired than those with MPA. Both PR3-GPA and MPO-GPA relapsed more frequently than MPA, but overall survival was significantly better (P < 0.01 and P < 0.05, respectively). Univariate analysis identified the following factors as predictors of a poor prognosis: MPA (P < 0.01), pulmonary UIP pattern (P < 0.005) Cr ≥ 1.7 mg/dl (P < 0.01) and absence of ENT involvement (P < 0.05), which were characteristics of MPA. In our cohort, MPO-GPA was most likely to affect older women and was associated with otitis media, nervous system involvement, mild renal impairment and more favorable outcome. It is clinically useful to differentiate MPO-GPA from MPA and PR3-GPA in patients with AAV.

In some patients with RA, dysfunction of p53 might play a role in the proliferation of the synovial tissue. G245D mutation might especially need further study as it is the first recurrently identified p53 mutation in RA and is also one of the frequently identified mutations in human cancers.

Rheumatoid arthritis (RA) and diabetes mellitus (DM) are associated with inflammation. We tried to investigate the influence of tumor necrosis factor inhibitors (TNFi) and tocilizumab (TCZ) on the glucose metabolism of RA patients. RA patients in whom treatment with TNFi or TCZ was initiated from 2008 to 2015 were studied based on their medical records. We analyzed patients whose glycosylated hemoglobin (HbA1c) levels were measured both before and 3 months after the initiation of these biologic agents. The association between HbA1c reduction and the treatment was evaluated. From 971 cases treated with these biologic agents, 221 cases whose medical records of HbA1c were available, were included (TNFi, n = 154; TCZ, n = 67). Both the TNFi and TCZ groups had significantly lower HbA1c values at 1 month and 3 months after the initiation of treatment (TNFi, p<0.001; TCZ, p<0.001). Although the pretreatment HbA1c values did not differ (TNFi, 6.2%; TCZ, 6.2%; p = 0.532), the 3-month treatment HbA1c values were lower (TNFi, 6.1%; TCZ, 5.8%; p = 0.010) and the changes in HbA1c (ΔHbA1c) were greater (TNFi, 0.1%; TCZ, 0.4%; p<0.001) in the TCZ group. The reduction of HbA1c—defined by the achievement of a ΔHbA1c of ≥0.5%—was associated with baseline diagnosis of diabetes mellitus, baseline diabetes treatment, hospitalization, medical change during the observation period, and TCZ. In the multivariate logistic regression analysis, TCZ was associated with the reduction of HbA1c in comparison to TNFi (adjusted OR = 5.59, 95% CI = 2.56–12.2; p<0.001). The HbA1c levels in RA patients were significantly lower after the initiation of TNFi or TCZ. Our study suggests that TCZ decreases the HbA1c levels in RA patients to a greater extent than TNFi.