Reciprocal expression and signaling of TLR4 and TLR9 in the pathogenesis and treatment of necrotizing enterocolitis

Steven C. Gribar, Chhinder P. Sodhi, Ward M. Richardson, Rahul J. Anand, George K. Gittes, Maria F. Branca, Adam Jakub, Xia Hua Shi, Sohail Shah, John A. Ozolek, David J. Hackam

Research output: Contribution to journalArticlepeer-review

176 Scopus citations


Necrotizing enterocolitis (NEC) is a common and often fatal inflammatory disorder affecting preterm infants that develops upon interaction of indigenous bacteria with the premature intestine. We now demonstrate that the developing mouse intestine shows reciprocal patterns of expression of TLR4 and TLR9, the receptor for bacterial DNA (CpG-DNA). Using a novel ultrasound-guided in utero injection system, we administered LPS directly into the stomachs of early and late gestation fetuses to induce TLR4 signaling and demonstrated that TLR4-mediated signaling within the developing intestine follows its expression pattern. Murine and human NEC were associated with increased intestinal TLR4 and decreased TLR9 expression, suggesting that reciprocal TLR4 and TLR9 signaling may occur in the pathogenesis of NEC. Enteral administration of adenovirus expressing mutant TLR4 to neonatal mice reduced the severity of NEC and increased TLR9 expression within the intestine. Activation of TLR9 with CpGDNA inhibited LPS-mediated TLR4 signaling in enterocytes in a mechanism dependent upon the inhibitory molecule IRAK-M. Strikingly, TLR9 activation with CpG-DNA significantly reduced NEC severity, whereas TLR9-deficient mice exhibited increased NEC severity. Thus, the reciprocal nature of TLR4 and TLR9 signaling within the neonatal intestine plays a role in the development of NEC and provides novel therapeutic approaches to this disease.

Original languageEnglish (US)
Pages (from-to)636-646
Number of pages11
JournalJournal of Immunology
Issue number1
StatePublished - Jan 1 2009
Externally publishedYes

ASJC Scopus subject areas

  • Immunology and Allergy
  • Immunology


Dive into the research topics of 'Reciprocal expression and signaling of TLR4 and TLR9 in the pathogenesis and treatment of necrotizing enterocolitis'. Together they form a unique fingerprint.

Cite this