SUMMARYPolymophonuclear cells (PMN) of healthy donors do not express major histocompatibility complex (MHC) class II antigens or the T-cell costimulatory molecules CD80 or CD86. Expression of these receptors, however, is seen in patients with chronic in¯ammatory diseases. We now report that, by culturing PMN of healthy donors with autologous serum, interferon-c (IFN-c) and granulocyte± macrophage colony-stimulating factor (GM-CSF), de novo synthesis of MHC class II, CD80 and CD86 could be induced. MHC class II-positive PMN acquired the capacity to present staphylococcus enterotoxin to peripheral T cells, apparent as induction of interleukin-2 (IL-2) synthesis and proliferation of the T cells. Moreover, the PMN also processed tetanus toxoid (TT) and induced proliferation of TT-speci®c T cells in a MHC class II-restricted manner. Taken together, these data indicate that PMN can be activated to function as accessory cells for T-cell activation.
ObjectivesTo confirm the effectiveness and safety of the interleukin 6-receptor antagonist tocilizumab in patients with rheumatoid arthritis (RA) in a setting close to real-life medical care in Germany.MethodsA multicentre open-label phase IIIb study was undertaken. Patients with active RA with a 28-joint Disease Activity Score (DAS28) >3.2 despite previous disease-modifying antirheumatic drugs (DMARDs) were treated with tocilizumab 8 mg/kg every 4 weeks. The primary end point was the proportion of patients achieving LDAS ≤3.2 at week 24; secondary end points included American College of Rheumatology (ACR), European League Against Rheumatism (EULAR) or Clinical Disease Activity Index (CDAI) responses and decrease in acute phase. Analyses in subgroups such as rheumatoid factor (RF)-positive versus RF-negative patients and patients with an inadequate response to treatment with DMARDs (DMARD-IR) versus those with an inadequate response to tumour necrosis factor (TNF) antagonists (TNF antagonist-IR) were performed. Safety was assessed by adverse event documentation.Results286 patients were treated and 83.6% completed the study. 41.6% had previously been treated with TNF antagonists. 57% of the intention-to-treat patients achieved the primary end point of LDAS, 47.6% achieved DAS remission <2.6 and a EULAR ‘good response’ was achieved by 54.9%; ACR50/70 response rates at week 24 were 50.7% and 33.9%, respectively. The mean±SD decrease in CDAI from baseline to week 24 was 71±29%. C reactive protein levels normalised rapidly within 1 week. Major improvements in fatigue, pain and morning stiffness were observed in the first 4 weeks and further improved until week 24. DAS28, EULAR and ACR responses at week 24 did not differ between RF-positive and RF-negative patients. TNF antagonist-naive patients responded better than patients who had previously failed on TNF antagonists. The safety profile of tocilizumab was comparable to that previously observed in the phase III trial programme. Serious infections were observed in 3.1% of patients.ConclusionsTocilizumab is highly effective in a setting close to real-life medical care with a rapid and sustained improvement in signs and symptoms of RA. A manageable safety profile was seen over the 24-week study period.
Helicobacter pylori induces cell death by apoptosis. However, the apoptosis-inducing factor is still unknown. The virulence factor vacuolating cytotoxin A (VacA) is a potential candidate, and thus its role in apoptosis induction was investigated in the human gastric epithelial cell line AGS. The supernatant from the vacA wild-type strain P12 was able to induce apoptotic cell death, whereas the supernatant from its isogenic mutant strain P14 could not. That VacA was indeed the apoptosis-inducing factor was demonstrated further by substantial reduction of apoptosis upon treatment of AGS cells with a supernatant specifically depleted of native VacA. Furthermore, a recombinant VacA produced in Escherichia coli was also able to induce apoptosis in AGS cells but failed to induce cellular vacuolation. These findings demonstrate that the vacuolating cytototoxin of H. pylori is a bacterial factor capable of inducing apoptosis in gastric epithelial cells.
LEF at a dosage of 30 mg/day appears to be effective in the prevention of major relapses in WG, however, this is associated with an increased frequency of adverse events. Further studies testing other dosing regimens of lower doses of LEF are needed to confirm these promising results in larger patients cohorts.
Objectives: To investigate infiltrated cells in the synovial fluid (SF) of inflamed joints of patients with rheumatoid arthritis (RA), with special reference to polymorphonuclear neutrophils (PMN) and their interaction with T cells. Methods: Expression on PMN of activation associated receptors CD14, CD64, CD83, and major histocompatibility complex (MHC) class II was examined in the SF of 15 patients with RA, as were the infiltrated T cells. SF cytokines were determined by enzyme linked immunosorbent assay (ELISA). To mimic the in vivo situation, co-culture experiments were carried out using PMN and T cells of healthy donors. Results: The SF contained activated T lymphocytes and abundant PMN. SF PMN expression of CD14 and CD64 was enhanced compared with peripheral blood. Of special interest was the observation that only the SF PMN expressed MHC class II antigens and CD83. Exposure to SF, which contained considerable amounts of cytokines (for example, interferon c (IFNc), tumour necrosis factor a, and interleukin 2), induced a similar receptor pattern on blood derived PMN of healthy donors. Furthermore, PMN acquired MHC class II and CD83 within 24 to 48 hours, when co-cultured with autologous T cells or T cell lines. This effect was also achieved by T cell supernatants, was dependent on protein synthesis, and could be inhibited by antibodies against IFNc. Conclusions: SF PMN from patients with RA undergo major alterations, including transdifferentiation to cells with dendritic-like characteristics, probably induced by T cell derived cytokines. Because MHC class II positive PMN are known to activate T cells, the mutual activation of PMN and T cells might contribute to the perpetuation of the local inflammatory process, and eventually to the destructive process in RA.
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