小儿呼吸道WU多瘤病毒感染免疫致病机制的初步研究

A preliminary study on immunopathogenesis of acute respiratory infection caused by WU Polyomavirus in children

目的了解WU多瘤病毒(WUPyV)在小儿呼吸道感染时其急性期外周血细胞因子的变化,以探讨该病毒感染的免疫致病机制。方法应用PCR技术对儿科急性呼吸道感染1 253例住院患儿的咽拭子及82例健康体检儿童咽拭子进行WUPyV核酸检测,并同时检测呼吸道合胞病毒(RSV)、人类博卡病毒(HBoV)、人偏肺病毒(hMPV)、腺病毒(ADV)、流感病毒A、B型(IFV)、副流感病毒1、3型(PIV)和鼻病毒(Rhv)共10种病毒。采用液相蛋白芯片技术同时对15例单纯WUPyV感染患儿、20例单纯RSV感染患儿、22例正常对照儿童外周血血清中12种细胞因子(IFN-γ、IL-1β、IL-1α、IL-2、IL-4、IL-6、IL-8、IL-10、IL-12p70、IL-12p40、IL-13、TNF-α)的含量进行检测。结果 1253例患儿WUPyV阳性32例(占2.55%),其中单纯WUPyV感染15例(46.88%),合并其他病毒感染的有17例(53.13%),分别为RSV、RHV、IVA、ADV;RSV阳性158例(占12.61%),其中单纯RSV感染85例,合并感染73例,与另9种病毒均存在混合感染情况。82例健康体检儿童10种病毒的PCR检查均阴性。单纯WUPyV组患儿外周血IL-6、IL-8、IL-1β、TNF-α、IL-12p40水平较正常对照组明显升高(P均<0.05),单纯RSV组患儿外周血IL-6、IL-8、IL-1β、TNF-α、IL-12p40水平也较正常对照组明显升高(P均<0.01),单纯WUPy组此5种细胞因子较正常对照组升高的程度均较单纯RSV组稍低,但两病毒组间此5种细胞因子差异无统计学意义(P均>0.05)。单纯WUPyV组及单纯RSV组患儿外周血IL-2、IL-4、IL-1α、INF-γ水平均稍高于对照组,但差异无统计学意义(P>0.05)。3组儿童外周血中几乎未检测到IL-10、IL-12p70、IL-13。结论 WUPyV感染可导致患儿免疫功能异常,其模式与RSV组感染导致的异常细胞因子改变类似但程度较轻。

Objective To study the immunopathogenesis of acute respiratory tract infection caused by WU polyomavirus（WUPyV） in children through changes of cytokines in peripheral blood.Methods Throat swabs collected from 1 253 childish patients with acute respiratory tract infection admitted in the Second Affiliated Hospital of Shantou University Medical College during July 2008 to May 2010 and from 82 healthy children were examined for WU polyomavirus by using PCR assay and 9 common respiratory infectious viruses（RSV,human bocavirus,human metapneumovirus,adenovirus,influenzavirus A and B,PIV 1 and 3 and rhinovirus） by using PCR or RT-PCR.Cytokines（IFN-γ,IL-1β,IL-1α,IL-2,IL-4,IL-6,IL-8,IL-10,IL-12p70,IL-12p40,IL-13 and TNF-α） were detected from serum of peripheral blood samples collected from 22 healthy children,15 patients infected with WUPyV and 20 patients infected with RSV by using Luminxe.Results In this study,32 of 1 253 specimens from patients with acute respiratory tract infection were positive for WU polyomavirus（2.55%）.WU polyomavirus was the only virus detected in 15 specimens（46.88%） from patients with acute respiratory tract infection,and 17 of 32（53.13%） specimens infected with WU polyomavirus were co-infected with other viruses such as RSV,ADV,IVA,and RHV,and 158 tested specimens from patients with acute respiratory tract infection were positive for RSV.RSV was the sole virus detected in 85 specimens（12.61%） from patients with acute respiratory tract infection,and 73 specimens with RSV were co-infected with other 9 kinds of viruses.All asymptomatic children were negative in virus examination.Levels of IL-6,IL-8,IL-1β,TNF-α and IL-12p40 were elevated in patients infected with WUPyV（P0.05）,and levels of IL-6,IL-8,IL-1β,TNF-α and IL-12p40 were elevated in patients infected with RSV（P0.01）.Levels of these 5 cytokines in patients infected with WUPyV were lower than those of patients infected with RSV,but their difference had no statistical significance（P0.05）.Levels of IL-2,IL-4,IL-1α and INF-γ in virus infected patients of these two groups were higher than those of healthy controls,but the difference also had no statistical significance（P0.05）.Levels of IL-10,IL-12p70 and IL-13 were nearly not detected in their serum samples,therefore these findings were not included in this analysis.Conclusion Infection with WU polyomavirus can cause abnormal immune function in children with acute respiratory tract infection,and its pattern was similar to those of children infected with RSV,but the degree of changes in cytokines was lower than those infected with RSV.