Martin T R, Ruzinski J T, Wilson C B, Skerrett S J
Medical Research Service, Seattle VA Medical Center, WA 98108.
J Infect Dis. 1995 Jan;171(1):134-44. doi: 10.1093/infdis/171.1.134.
Age-dependent maturation of the intrapulmonary inflammatory responses to bacterial lipopolysaccharide (LPS) was studied because nosocomial gram-negative infections cause morbidity in newborn infants. Escherichia coli LPS or live E. coli were injected into the airways of neonatal or adult rats; intrapulmonary recruitment of leukocytes was measured 6 h later. Neonates showed age- and dose-dependent impairment of intrapulmonary neutrophil recruitment after intratracheal administration of LPS or live E. coli that persisted for the first 28 days of life. Neonatal and adult alveolar macrophages released similar amounts of neutrophil chemotactic activity and tumor necrosis factor in response to incubation with LPS in vitro. Treatment of neonates with intratracheal or systemic interferon-gamma did not augment the response to LPS. Thus, intrapulmonary inflammatory responses to LPS and gram-negative bacteria are impaired early in life and do not approach adult levels until approximately 4 weeks of age.
由于医院获得性革兰氏阴性菌感染会导致新生儿发病，因此研究了肺部对细菌脂多糖（LPS）的炎症反应随年龄的成熟情况。将大肠杆菌LPS或活的大肠杆菌注入新生大鼠或成年大鼠的气道；6小时后测量肺内白细胞募集情况。新生大鼠在气管内给予LPS或活的大肠杆菌后，肺内中性粒细胞募集出现年龄和剂量依赖性损害，这种损害在出生后的前28天持续存在。新生和成年肺泡巨噬细胞在体外与LPS孵育后释放的中性粒细胞趋化活性和肿瘤坏死因子量相似。气管内或全身给予新生儿干扰素-γ并不能增强对LPS的反应。因此，肺部对LPS和革兰氏阴性菌的炎症反应在生命早期受损，直到大约4周龄时才接近成年水平。
