Endotoxin and NO induce MIP-1 gamma gene transcription in ANA-1 murine macrophages

The host response to gram-negative endotoxin is characterized by an influx of inflammatory cells into host tissues, mediated in part by localized prod uction of chemokines. In this study, using subtractive suppression hybridiz ation analysis, we demonstrate that ANA-1 murine macrophages produce the CC chemokine, MIP-1 gamma, in response to LPS-mediated NO production. Gene tr anscription and protein translation are upregulated in the setting of LPS-i nduced NO synthesis. However, NO alone is a necessary but insufficient cofa ctor for induction of MIP-1 gamma protein expression; an NO-independent LPS signalling pathway is also required. This study suggests a novel mechanism by which NO modulates the host inflammatory response to endotoxin, (C) 200 0 Academic Press.