Local perfusion of the dorsal root ganglion (DRG) with tumor necrosis factor alpha (TNF-alpha) in rats induces cutaneous hypersensitivity to mechanical stimuli. Thus we investigated the cellular mechanisms of TNF-alpha-induced mechanical hyperalgesia. The L(4) and L(5) DRGs with the sciatic nerves attached were excised from rats for in vitro dorsal root microfilament recording. After baseline r...

Tumor necrosis factor alpha (TNF alpha) localizes to the epidermis when injected in vivo, but its role in the skin has heretofore not been evaluated. As a first approach to assessing the role of TNF alpha in the skin, we evaluated the binding and biological effects of TNF alpha on human neonatal foreskin keratinocytes maintained in culture. We found that TNF alpha at 0.3-1.0 nM inhibited prolif...

The purpose of this study was to evaluate the effect of theophylline on tumour necrosis factor-alpha (TNF-alpha) release by human blood monocytes (BMo), and rat BMo and alveolar macrophages (AM). BMo and AM were incubated in the absence or presence of theophylline, and the cell-free supernatants were harvested and tested for TNF-alpha activity by bioassay. Theophylline dose-dependently reduced ...

We have found reduced activity of tumor necrosis factor (TNF)-alpha accompanying resolving and fibrosing alveolitis induced in NMRI mice by mineral particles (MnO2 and SiO2, respectively), which is in apparent contradiction to the well-recognized proinflammatory and profibrotic activities of this cytokine. The objective of this study was to examine the mechanisms involved in this paradoxical re...

Kupffer cells are important for bacterial clearance and cytokine production during infection. We have previously shown that severe infection with Pseudomonas aeruginosa ultimately results in loss of Kupffer cells and hepatic bacterial clearance. This was associated with prolonged hepatic inflammation. However, there is a period of time during which there is both preserved hepatic bacterial clea...

PURPOSE to compare the expression of tumor necrosis factor-alpha (TNF-alpha) in ovular membranes with premature rupture (MPR) and with opportune rupture; to verify the association between the expression of the TNF-alpha in ovular membranes and the degree of chorioamnionitis, correlating the expression of the TNF-alpha and the membranes' time of rupture. METHODS ovular membranes from 31 partur...

We have recently demonstrated that tumor necrosis factor alpha (TNF-alpha) potentiates interleukin 3 (IL-3) and granulocyte/macrophage colony-stimulating factor-induced growth of CD34+ hematopoietic progenitor cells (HPC), and favors the generation of dendritic/Langerhans cells. The stimulatory effect of TNF-alpha was detailed in the present study. Thus, CD34+ HPC entering in cycle (S/G2M) afte...

A cell-by-cell analysis of the secretory ability of stimulated, individual alveolar macrophages (AMs) was performed through use of a tumor necrosis factor alpha (TNF-alpha) reverse hemolytic plaque assay. Two functional end points were measured: the percentage of AMs that were TNF-alpha secretors and the cumulative amount of TNF-alpha secreted by AMs (average plaque area, microns 2). Lipopolysa...

BACKGROUND Vascular calcification is an ectopic calcification that commonly occurs in atherosclerosis. Because tumor necrosis factor-alpha (TNF-alpha), a pleiotropic cytokine found in atherosclerotic lesions, is also a regulator of bone formation, we investigated the role of TNF-alpha in in vitro vascular calcification. METHODS AND RESULTS A cloned subpopulation of bovine aortic smooth muscle...