OBJECTIVE: We have shown previously that interleukin 1 (IL-1) signaling is not necessary for bacterially induced preterm delivery in mice. We now test whether combined signaling of IL-1 and tumor necrosis factor (TNF) is critical for this process. STUDY DESIGN: Female mice lacking the type I receptors for IL-1 and TNF (Il1r1/Tnfrsf1a double-knockouts) and normal controls underwent intrauterine inoculation with killed Escherichia coli bacteria on day 14.5 of a 19- to 20-day gestation. Preterm delivery rates within 48 hours were recorded and gene expression was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS: Il1r1/Tnfrsf1a double-knockout mice had significantly lower rates of preterm delivery than controls (8% vs 69% with 7 x 10(7) bacteria, P = .002, and 52% vs 81% with 1.4 x 10(8) bacteria, P = .003) and significantly lower myometrial levels of cyclooxygenase (COX)-2, but not COX-1 mRNA. There were no genotype- or treatment-related differences in cervicovaginal and lower uterine expression of mRNAs for a variety of genes associated with cervical ripening. CONCLUSION: The combination of IL-1 and TNF signaling plays a critical role in bacterially induced labor and myometrial COX-2 production in the mouse. Cervical gene expression patterns during bacterially induced preterm labor suggest fundamental differences from spontaneous term labor in the cervical ripening process.
OBJECTIVE: We have shown previously that interleukin 1 (IL-1) signaling is not necessary for bacterially induced preterm delivery in mice. We now test whether combined signaling of IL-1 and tumor necrosis factor (TNF) is critical for this process. STUDY DESIGN: Female mice lacking the type I receptors for IL-1 and TNF (Il1r1/Tnfrsf1a double-knockouts) and normal controls underwent intrauterine inoculation with killed Escherichia coli bacteria on day 14.5 of a 19- to 20-day gestation. Preterm delivery rates within 48 hours were recorded and gene expression was analyzed by reverse transcription-polymerase chain reaction (RT-PCR). RESULTS:Il1r1/Tnfrsf1a double-knockout mice had significantly lower rates of preterm delivery than controls (8% vs 69% with 7 x 10(7) bacteria, P = .002, and 52% vs 81% with 1.4 x 10(8) bacteria, P = .003) and significantly lower myometrial levels of cyclooxygenase (COX)-2, but not COX-1 mRNA. There were no genotype- or treatment-related differences in cervicovaginal and lower uterine expression of mRNAs for a variety of genes associated with cervical ripening. CONCLUSION: The combination of IL-1 and TNF signaling plays a critical role in bacterially induced labor and myometrial COX-2 production in the mouse. Cervical gene expression patterns during bacterially induced preterm labor suggest fundamental differences from spontaneous term labor in the cervical ripening process.
Authors: Daniel B DiGiulio; Roberto Romero; Juan Pedro Kusanovic; Ricardo Gómez; Chong Jai Kim; Kimberley S Seok; Francesca Gotsch; Shali Mazaki-Tovi; Edi Vaisbuch; Katherine Sanders; Elisabeth M Bik; Tinnakorn Chaiworapongsa; Enrique Oyarzún; David A Relman Journal: Am J Reprod Immunol Date: 2010-03-21 Impact factor: 3.886
Authors: Clare A Berry; Ilias Nitsos; Noah H Hillman; J Jane Pillow; Graeme R Polglase; Boris W Kramer; Matthew W Kemp; John P Newnham; Alan H Jobe; Suhas G Kallapur Journal: Reprod Sci Date: 2011-04-14 Impact factor: 3.060
Authors: Michael G Gravett; Kristina M Adams; Drew W Sadowsky; Alexandra R Grosvenor; Steven S Witkin; Michael K Axthelm; Miles J Novy Journal: Am J Obstet Gynecol Date: 2007-11 Impact factor: 8.661