Molloy Eleanor J, O'Neill Amanda J, Grantham Julie J, Sheridan-Pereira Margaret, Fitzpatrick John M, Webb David W, Watson R William G
Department of Surgery, Mater Misericordiae University Hospital, University College Dublin, Dublin, Ireland.
Pediatr Res. 2004 Jul;56(1):99-103. doi: 10.1203/01.PDR.0000130473.30874.B6. Epub 2004 May 5.
Labor is a mild proinflammatory state that is associated with fetal leukocytosis. Elective cesarean section has been linked with increased neonatal morbidity, which may be partially immune mediated. We hypothesized that labor may alter neutrophil phenotype and thereby decrease neonatal complications. We characterized neutrophil function and survival in normal neonates after either uncomplicated vaginal delivery (VD) or elective cesarean section (CS) without labor. Spontaneous neutrophil apoptosis is delayed in cord blood neutrophils of neonates after normal labor (VD) compared with CS, as assessed by propidium iodide DNA incorporation using flow cytometry. This demonstrates their ability to maintain an inflammatory response. CD11b expression on neonatal neutrophils after CS is decreased, providing further evidence of altered activation or priming. Lipopolysaccharide responsiveness, characterized by CD11b and apoptosis, is similar in VD and adults, but CS-derived neutrophils are unresponsive. Baseline TLR-4 levels are elevated in CS in contrast to the other groups, although expression is not up-regulated by lipopolysaccharide co-incubation. Neonatal neutrophil survival and function are altered by labor and may increase antibacterial function and neutrophilia. This suggests that labor of any duration may be immunologically beneficial to the normal term neonate.
分娩是一种轻度的促炎状态，与胎儿白细胞增多有关。择期剖宫产与新生儿发病率增加有关，这可能部分是由免疫介导的。我们假设分娩可能会改变中性粒细胞表型，从而减少新生儿并发症。我们对正常新生儿在无并发症的阴道分娩（VD）或未经历分娩的择期剖宫产（CS）后的中性粒细胞功能和存活情况进行了表征。通过流式细胞术使用碘化丙啶掺入法评估，与剖宫产相比，正常分娩（VD）后新生儿脐带血中性粒细胞的自发凋亡延迟。这证明了它们维持炎症反应的能力。剖宫产术后新生儿中性粒细胞上的CD11b表达降低，这为激活或致敏改变提供了进一步证据。以CD11b和凋亡为特征的脂多糖反应性在阴道分娩的新生儿和成人中相似，但剖宫产来源的中性粒细胞无反应。与其他组相比，剖宫产时基线TLR-4水平升高，尽管脂多糖共孵育未上调其表达。分娩会改变新生儿中性粒细胞的存活和功能，并可能增强抗菌功能和中性粒细胞增多。这表明任何时长的分娩在免疫方面可能对足月儿有益。
