Tumor necrosis factor (TNF)-α has been postulated to play an important physiologic as well as pathologic role within the developing brain. In the present study, we found that human fetal microglial cells released abundant amounts of TNF-α upon stimulation with lipopolysaccharide (LPS). Treatment of microglial cell cultures with antibodies specific to interleukin (IL)-6, IL-10, and transforming growth factor (TGF)-β augmented LPS-stimulated release of TNF-α. Each of these cytokines dose-dependently suppressed TNF-α release. Also, TNF-α mRNA expression was inhibited by each of these cytokines. By way of contrast, treatment of microglial cell cultures with IL-α or IL-1β alone or in the presence of LPS, resulted in increased release of TNF-α, and IL-1 stimulated the expression of TNF-α mRNA. These findings suggest that these cytokines are likely to modify the beneficial and harmful effects of TNF-α within the developing brain.
- Tumor necrosis factor-α