Interleukin-6 is neither necessary nor sufficient for preterm labor in a murine infection model.
OBJECTIVE
The aim of this study was to investigate the role of interleukin 6 (IL-6) in a murine model of bacterially induced preterm delivery.


METHODS
On day 14.5 of a 19-20-day gestation, female mice underwent one of two interventions. In experiment 1, pregnant right uterine horns were injected at laparotomy with 0.5-20 microg of recombinant human IL-6 (rhIL-6). In experiment 2, IL-6-deficient (IL-6(-/-)) and wild-type control (IL-6(+/+)) mice underwent intrauterine inoculation with 10(5) to 10(8) heat-killed Escherichia coli organisms. Preterm delivery and maternal survival rates were recorded.


RESULTS
In experiment 1, doses as high as 20 microg of IL-6 per mouse resulted in up-regulation of acute phase reactants but did not cause preterm delivery or other adverse maternal or fetal effects. In experiment 2, in bacterially inoculated mice, the absence of maternal and fetal IL-6 had no effect on preterm delivery rates.


CONCLUSIONS
IL-6 was neither sufficient nor necessary for preterm delivery in these murine models.
D000818:Animals; D001424:Bacterial Infections / Q000150:complications*; D004927:Escherichia coli Infections / Q000150:complications; D005260:Female; D005333:Fetus / Q000378:metabolism; D005838:Genotype; D005865:Gestational Age; D006801:Humans; D015850:Interleukin-6 / Q000008:administration & dosage / Q000172:deficiency / Q000502:physiology*; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D007752:Obstetric Labor, Premature / Q000382:microbiology*; D011247:Pregnancy; D011994:Recombinant Proteins; D014591:Uterine Diseases / Q000382:microbiology
D015850:Interleukin-6; D011994:Recombinant Proteins