IL-1 receptor-associated kinase and low molecular weight GTPase RhoA signal molecules are required for bacterial lipopolysaccharide-induced cytokine gene transcription

Ling Yu Chen, Bruce L. Zuraw, Fu Tong Liu, Shuang Huang, Zhixing K. Pan

Research output: Contribution to journalArticle

47 Scopus citations


Proinflammatory cytokines such as IL-1, TNF, IL-6, and IL-8 are produced by leukocytes in response to bacteria or bacterial components. A great deal has been learned during the past few years about the synthesis and release of proinflammatory cytokines by leukocytes; however, relatively little is known about the intracellular events that lead to leukocyte proinflammatory cytokine gene transcription. This study examined the signal transduction pathway of IL-8 induction by bacterial LPS. Stimulation of monocytes with LPS rapidly activated RhoA, and pretreatment of monocytes with a RhoA inhibitor, C3 transferase exoenzyme, effectively blocked LPS-induced IL-8 gene expression. Overexpression of dominant negative RhoA (T19N) or IL-1R-associated kinase completely inhibited LPS-stimulated reporter gene expression. Induction of IL-8 was also inhibited by dominant negative IκB kinase and myeloid differentiation protein (MyD88). These results indicate that RhoA and IL-1R-associated kinase are novel signal transducers for LPS-induced Toll-like receptor 4-mediated proinflammatory cytokine synthesis in human monocytes.

Original languageEnglish (US)
Pages (from-to)3934-3939
Number of pages6
JournalJournal of Immunology
Issue number7
StatePublished - Oct 1 2002


ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology

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