The role of polymorphonuclear leukocyte in Staphylococcus aureus Panton-Valentine leukocidin-induced acute lung inflammation and injury
10.3760/cma.j.issn.1000-6680.2012.03.002
- VernacularTitle:多形核粒细胞在金黄色葡萄球菌杀白细胞素相关肺炎性损伤中的作用
- Author:
Cuiping ZHANG
;
Xiaoling MA
;
Wenjiao CHANG
;
Xin ZHOU
- Publication Type:Journal Article
- Keywords:
Staphylococcusaureus;
Neutrophils;
Pneumonia;
Disease models,animal
- From:
Chinese Journal of Infectious Diseases
2012;30(3):131-136
- CountryChina
- Language:Chinese
-
Abstract:
ObjectiveTo explore the role of polymorpbonuclear leukocyte (PMN) in PantonValentine leucocidin (PVL)-induccd acute lung inflammation and injury. Methods Fifteen New Zealand rabbits were divided into 3 groups with five rabbits in each group.The controls were treated with pbosphate buffer solution (PBS),the rabbits with normal granulocyte in rPVL group were treated with endotracheal instillation of rPVL,the granulocytopenia rabbits in vincristine (VCR) +rPVL group were firstly treated with VCR,thcn with endotracheal instillation of rPVL.Nine hours after injection,the peripheral blood and bronchoalveolar lavage fluid (BALF) were collected for counting PMN.The lactate dehydrogenase (LDH) activity in BALF,lung permeability index (LPI),PMN apoptosis and necrosis and the release of reactive oxygen species (ROS)in BALF were measured.After the rabbits sacrificed,the lung tissue samples were collcctcd for dctcrmining wet/dry (W/D) ratio and histopathological examination.The comparison among groups was done by t test.ResultsThe PMN count in the peripheral blood was (2.69=0.34) × 10 mL in rPVL group,which was significantly lower than control group [(3.63 ± 0.38) × 105/mL] (t =4.12,P＜0.05).The PMN counts in BALF in control group,rPVL group and VCR+rPVL group were (0.57±0.01 ) ×106/mL,(3.01±0.02) × 106/mL and (0.10±0.02) × 106/mL,respectively; that in rPVL group was significantly higher than those in control group (t=254.39,P＜0.05).The LDH activity,LPI and W/D ratio in rPVL group were all significantly higher than control group,while those in VCR+rPVL group were not significantly different from control group.The PMN apoptosis rate and necrosis rate in VCR+rPVL groupwere (1.17±0.24)％ and (1.13±0.17)％,respectively.The releases of ROS (meanfluorescence intensity) in rPVL group,control group and VCR+rPVL group were 1.56±0.39,0.41±0.03 and 0.39±0.02,respectively,and that in rPVL group was significantly higher (t=6.58,P＜0.05).Histopathological examination of the lung showed the diffuse infiltration of inflammatory cells,hemorrhage and edema in rPVL group,wbile there was only thimbleful infiltration of inflammatory cells observed in surrounding bronchia and alveolar septun in VCR-rPVL group.ConclusionsrPVL can induce lung inflammation and injury in rabbits with normal granulocyte,but not in neutropenic rabbirs.Lung inflammation and injury may be the result of recruitment,aggregation and subsequent lysis and/or activation of PMN,which can damage the lung by releasing the contents of cytotoxic granules and/or reactive oxygen metabolites.
