EXPERIMENTAL MODEL FOR CHORIODECIDUAL INFECTION & PRETERM LABOR IN MACAQUES

宫内感染是早产的重要原因。 我们 先前已经证明实验性羊膜内感染 导致羊水（AF）连续增加 细胞因子（TNF和IL-1b）和前列腺素（PGE 2和PGF 2a）， 然后是早产和分娩 然而， 绒毛膜蜕膜感染在早产中的作用尚不清楚。 表征 绒毛膜蜕膜后的病理生理过程 感染，我们利用慢性仪器恒河猴与 定时妊娠，其中绒毛膜蜕膜感染是由 接种低接种物（<102 cfu; n=2）、中等接种物（<102 cfu; n=2） 接种物（103-104 cfu; n=4）或高接种物（>105 cfu; n=3） B链球菌（GBS）进入绒毛膜蜕膜间隙。 接种后，2个低接种物中无一例发生分娩， 4只中度接种物，2/3只高接种物动物。 在4 感染诱导分娩的动物，子宫内膜厚度增加 接种后21小时（14-30小时）发生收缩。 子宫收缩力增加之前，羊膜腔内 在4只动物中的3只中，平均12小时（6-24 小时）。 AF促炎细胞因子和前列腺素浓度 在这5只动物中， 接种疫苗并没有导致分娩。 相比之下， 在4例AF患者中观察到AF细胞因子和白藜芦醇增加， 在GBS羊膜内浸润后而不是之前分娩的动物 中位AF浓度（pg/ml）事件TNF IL-1b PGE 2 PGF 2a接种前50 <20 430 86分娩900 110 5，550 316 这些结果表明， 绒毛膜蜕膜接种可上升至羊膜腔， 随着羊膜内感染的建立，早产 包围 与此相反，绒毛膜蜕膜接种，不同时 羊膜腔感染未导致早产。

Intrauterine infection is an important cause of preterm birth. We have previously demonstrated that experimental intraamniotic infection in rhesus monkeys leads to sequential increases in amniotic fluid (AF) cytokines (TNF and IL-1b) and prostaglandins (PGE2 and PGF2a), followed by preterm labor and delivery. However, the role of choriodecidual infection in preterm labor is unclear. To characterize the pathophysiologic sequence of events following choriodecidual infection, we utilized chronically instrumented rhesus monkeys with timed gestations in which choriodecidual infection was established by inoculation of either a low inoculum (<102 cfu; n=2), moderate inoculum (103-104 cfu; n=4), or high inoculum (>105 cfu; n=3) of Group B streptococcus (GBS) bacteria into the choriodecidual space. Following inoculation, labor occurred in none of 2 low inoculum, 2 of 4 moderate inoculum, and in 2 of 3 high inoculum animals. In the 4 animals with infection-induced labor, increases in uterine contractility occurred 21 hours (14-30 hrs) after inoculation. Increases in uterine contractility were preceded by intraamniotic invasion by the GBS in 3 of 4 animals by an average of 12 hours (6-24 hrs). AF proinflammatory cytokine and prostaglandin concentrations did not rise above pre-inoculation levels among those 5 animals in which inoculation did not result in labor. In contrast, significant increases in AF cytokines and prostaglandins were observed in the 4 laboring animals after, but not before, intraamniotic invasion of GBS Median AF Concentrations (pg/ml) Event TNF IL-1b PGE2 PGF2a Pre-inoculation 50 <20 430 86 Onset Labor 900 110 5,550 316 Delivery 1,320 844 15,754 1,474 These results demonstrate that choriodecidual inoculation may ascend to the amniotic cavity and that following the establishment of intraamniotic infection, preterm labor ensues. In contrast, choriodecidual inoculation without concurrent intraamniotic infection did not lead to preterm labor.