Transient lipopolysaccharide-induced cytokine responses in the maternal serum and amniotic fluid of the guinea pig

The aim of this study was to characterize the pregnant guinea pig cytokine time course following a maternal inflammatory insult. Pregnant guinea pigs (n = 34) were injected intraperitoneally with 100 μg/kg lipopolysaccharide (LPS) at 70% gestation and euthanized at 24 hours, 48 hours, or 5 days. Control animals were euthanized at 70% gestation without LPS exposure. Interleukin (IL)-6, IL-1β, and tumor necrosis factor-alpha (TNF-α) were quantified in the maternal serum and amniotic fluid by an enzyme-linked immunosorbent assay. IL-6 and IL-1β concentrations were elevated in the maternal serum at 24 hours and returned to control levels by 5 days. In the amniotic fluid, IL-6 peaked at 48 hours and IL-1β at 24 hours. TNF-α levels were not significantly increased. Maternal intraperitoneal LPS injection produces transient increases in cytokine concentrations in the maternal serum and amniotic fluid within 5 days, further implicating the cytokines as mediators of fetal white matter damage.