In vitro infection with nontypeable Haemophilus influenzae in a model of human lung tissue and cells
Nontypeable Haemophilus influenzae(NTHI)is frequently associated with acute exacerbation of chronic obstructive pulmonary disease. To study the interaction between NTHI and lung tissues we established a model of in vitro acute infection in vital human lung specimens from pulmonary lobectomy. Lung specimens，human blood monocytes and a lung epithelial cell line(A549)were infected with a uspension of 108 colony forming units(cfu)x ml-1 for 4h and 24h respectively. Presence of NTHI DNA was detected using in situ hybridization(ISH)in lung tissue fixated with HOPE-solution. IL-8 release from lung tissues and cells was determined by ELISA，the phospho-p38 MAPK in lung cells was examined by Western Blot and expression of the NF-kappaB p65 was analysed using flow cytometry. The expression of NTHI DNA was observed in 70-85％ of alveolar macrophages(AM)and 15-25％ of alveolar epithelial cells(AEC)in infected lung tissues(n=18). NTHI infection induced a time-dependent secretion of IL-8 in monocytes，A549cells and lung specimens，whereas the complete pathogen showing the strongest inflammatory capacity compared to soluble cytoplasmatic fraction(SCF)and envelope protein(EP)from NTHI. Similar results were found in A549cells regarding expression of the NF-kB p65(NTHI：13-17 vs. SCF：3-5 and EP：4-7 mean fluorescence intensity). Our study demonstrates a novel tool to analyse cellular events in the interaction between NTHI and lung tissues. We conclude that AM and AEC may serve as important host cells for primary NTHI infection. Our results confirm that IL-8 plays a significant role in the pathogenesis of NTHI infection and MAPK and NF-kB are probably involved in signal transduction.
Feng Xu Daniel Droemann HuahaoShen Klaus Dalhoff
Department of Respiratory Medicine,Second Affiliated Hospital,Zhejiang University,Hangzhou,Zhejiang, Medical Clinic III,University of Schleswig-Holstein,Campus Luebeck,Luebeck,Schleswig-Holstein,German
国内会议
浙江金华
英文
2006-06-01（万方平台首次上网日期，不代表论文的发表时间）