INDUCTION OF A MACROPHAGE-LIKE NITRIC-OXIDE SYNTHASE IN CULTURED RAT AORTIC ENDOTHELIAL-CELLS - IL-1 BETA-MEDIATED INDUCTION REGULATED BY TUMOR-NECROSIS-FACTOR-ALPHA AND IFN-GAMMA

Citation
C. Suschek et al., INDUCTION OF A MACROPHAGE-LIKE NITRIC-OXIDE SYNTHASE IN CULTURED RAT AORTIC ENDOTHELIAL-CELLS - IL-1 BETA-MEDIATED INDUCTION REGULATED BY TUMOR-NECROSIS-FACTOR-ALPHA AND IFN-GAMMA, The Journal of immunology, 151(6), 1993, pp. 3283-3291
Citations number
50
Categorie Soggetti
Immunology
Journal title
The Journal of immunology
ISSN journal
00221767 → ACNP
Volume
151
Issue
6
Year of publication
1993
Pages
3283 - 3291
Database
ISI
SICI code
0022-1767(1993)151:6<3283:IOAMNS>2.0.ZU;2-2
Abstract
We investigated the effects of murine rTNF-alpha, human rIL-1beta, and rat rIFN-gamma in various concentrations and/or combinations on induc ible nitric oxide (NO) production in primary cultures of rat aortic en dothelial cells. Northern blot analysis of total RNA from induced and control cultures using the cloned mouse macrophage gene of inducible N O synthase as probe as well as polymerase chain reaction using a speci fic primer sequence gave a positive signal for activated cells only. A RNA approximately 4.4 kb of length similar to the inducible form of N O synthase in macrophages was labeled. The concentration of nitrite as a stable reaction product of NO in culture supernatants was determine d 24 h after incubation with the various cytokines. IL-1beta alone (40 to 1000 U/ml) induced formation of increasing amounts of nitrite with increasing concentrations of IL-1beta present. Neither TNF-alpha alon e (10 to 2000 U/ml) nor IFN-gamma alone (25 to 500 U/ml) showed signif icant effects on nitrite production. Simultaneous incubation with low concentrations of TNF-alpha (less-than-or-equal-to 100 U/ml) and IL-1b eta abrogated the induction effect of IL-1beta. Conversely, addition o f high concentrations of TNF-alpha (greater-than-or-equal-to 500 U/ml) led to near maximal levels of nitrite formation even at lowest IL-1be ta concentrations (40 U/ml). In addition, simultaneous incubation of e ndothelial cells with IFN-gamma plus IL-1beta and/or TNF-alpha led to near maximal NO production of endothelial cells, even at lowest IFN-ga mma concentrations (25 U/ml). We hypothesize that the regulating effec t of TNF-alpha may in vivo help to prevent local inflammatory response s from spreading to intact sites.