UNLABELLED Infectious complications are not rare in rheumatoid arthritis (RA), and the susceptibility to infections is increased during treatment with TNF blocking agents. As a possible mechanism contributing to that, we assessed the modulation of cytokine production induced by TNF neutralization. METHODS Whole blood cultures from six healthy volunteers and 13 RA patients starting therapy wit...

Tumor necrosis factor (TNF) is a monocyte-derived protein cytotoxic or cytostatic for some tumor cell lines. Here we show that highly purified E. coli-derived recombinant human TNF stimulated the growth of human FS-4 diploid fibroblasts. Stimulation of cell growth was demonstrable at a TNF concentration of 10 pg/ml (3 X 10(-13) M). Maximal stimulation was attained at TNF concentrations of 10 ng...

The innate and adaptive immune responses of dendritic cells (DCs) to enteroinvasive Escherichia coli (EIEC) infection were compared with DC responses to Shigella flexneri infection. EIEC triggered DCs to produce interleukin (IL)-10, IL-12 and tumour necrosis factor (TNF)-α, whereas S. flexneri induced only the production of TNF-α. Unlike S. flexneri, EIEC strongly increased the expression of to...

Objectives. Neutralization of TNF-a with either monoclonal antibodies or soluble receptors, although not curative, has significant clinical benefit in patients with rheumatoid arthritis (RA). In contrast, blockade of TNF-a has little clinical benefit in the majority of patients with systemic inflammatory response syndrome (SIRS) in spite of the identification of TNF-a as a key factor in its pat...

Sphingosine is a biologically active derivative of sphingomyelin. It affects diverse cellular functions and its mechanism(s) of action is poorly defined. Tumor necrosis factor alpha (TNF alpha) has recently been shown to rapidly induce sphingomyelin turnover, implicating this metabolic pathway in TNF alpha signal transduction. Because TNF alpha is known to induce prostaglandin E2 (PGE2) product...

BACKGROUND Recombinant proteins expressed in Escherichia coli vectors are generally contaminated with endotoxin. In this study, we evaluated the ability of Polymyxin B to neutralize the effect of LPS present as contaminant on Schistosoma mansoni recombinant proteins produced in E. coli in inducing TNF-alpha and IL-10. Peripheral blood mononuclear cells from individuals chronically infected with...

Neutrophils play an important role in intestinal inflammation by interacting with intestinal epithelial cells. In this study, we evaluated neutrophil adhesion to intestinal epithelial cells using intestinal epithelial cell line HT29 stimulated with tumor necrosis factor alpha (TNF-alpha) and histamine for a short time (30 min). The TNF-alpha and histamine stimulation markedly increased neutroph...

Hemorrhagic shock causes myocardial contractile depression. Although this myocardial disorder is associated with increased expression of tumor necrosis factor-alpha (TNF-alpha), the role of TNF-alpha as a myocardial depressant factor in hemorrhagic shock remains to be determined. Moreover, it is unclear which TNF-alpha receptor mediates the myocardial depressive effects of TNF-alpha. Toll-like ...