摘要
炎性介质如粒细胞集落刺激因子(G-CSF)从骨髓释放多形核白细胞(PMNL)。这种生长因子用于促进宿主对感染的反应,但其对炎症部位白细胞行为的影响尚不清楚。本研究检测了链球菌肺炎模型中G-CSF从骨髓释放的PMNL的隔离和迁移。在兔体内注射人G-CSF (n=6)或生理盐水(n=3) 8小时后,用胸腺嘧啶类似物5'-溴-2'-脱氧尿苷(BrdU)标记骨髓中的PMNL(PMNL(BrdU)),并作为骨髓中新释放的PMNL的标记物。免疫组化检测肺和血液中的PMNL(BrdU)。G-CSF预处理使8 h时循环PMNL(3.6+/-0.4(均值+/-SEM)至8.3+/-1X10(9) x L(-1), p<0.05)和PMNL(BrdU)(5.4+/-2.1至12.5+/-3.1%,p<0.05)计数升高,随后2 h肺炎引起的计数没有进一步升高。这些计数在对照组中没有变化。肺形态测量学研究显示,G-CSF组肺毛细血管中分离的PMNL总数增加,且brdu标记的PMNL百分比高于循环血液中(p<0.05)。在G-CSF组中,只有11.2+/-2.6%的PMNL是肺毛细血管中PMNL(BrdU),而肺毛细血管中PMNL(BrdU)为50.8+/-8%。 In vitro studies showed PMNL(BrdU) released from the bone marrow by G-CSF are less deformable than unlabelled circulating PMNL (p<0.01). It is concluded that granulocyte colony-stimulating factor treatment causes the marrow to release polymorphonuclear leukocytes that preferentially sequester in lung microvessels but are slow to migrate out of the vascular space into the airspace at the pneumonic site.