呼吸道合胞病毒的蛋白特征及抗原变异

呼吸道合胞病毒是非节段性的单链负股RNA病毒，是引起婴幼儿下呼吸道感染的重要原因。本文就近年来对呼吸道合胞病毒的蛋白特征和抗原变异的研究作一综述。     

呼吸道合胞病毒下呼吸道感染对机体细胞免疫的影响

为研究呼吸道合胞病毒（ＲＳＶ）急性下呼吸道感染（ＡＬＲＩ）的细胞免疫变化，对２５例病儿外周血白细胞介素２（ＩＬ－２）和可溶性白细胞介素２受体（ｓＩＬ－２Ｒ）水平、Ｔ细胞白细胞介素２受体（ＩＬ－２Ｒ）表达率和Ｔ细胞亚群百分率进行检测。结果显示，急性期病儿外周血ＩＬ－２水平明显低于恢复期和正常对照组，Ｔ细胞ＩＬ－２Ｒ表达率亦明显降低，而ｓＩＬ－２Ｒ水平却显著增高。急性期病儿ＩＬ－２水平与Ｔ细胞ＩＬ－２Ｒ表达率和ＣＤ＋４细胞百分率呈正相关，与ｓＩＬ－２Ｒ水平和ＣＤ＋８细胞百分率呈负相关；ｓＩＬ－２Ｒ水平与Ｔ细胞ＩＬ－２Ｒ表达率呈负相关，与临床严重程度呈正相关。上述各项免疫指标异常均提示ＲＳＶ感染时机体存在细胞免疫功能紊乱。     

强直性脊柱炎TH亚群激活及T细胞活化状态研究

目的 :研究强直性脊柱炎 (AS)患者TH1 TH2细胞激活状态及T细胞活化状况 ,探讨其发病机理。方法 :运用流式细胞仪 (CBA)法检测 35例AS患者TH1(INF γ、TNF α、IL 2 )、TH2 (IL 10、IL 5、IL 4 )细胞因子水平以及外周血淋巴细胞CD3 、CD4 、CD8 T细胞、B细胞 (CD19 )、NK细胞 (CD16 5 6 )和CD3 HLA DR 、CD4 HLA DR 、CD8 HLA DR T细胞百分率 ,并与健康对照组比较。结果 :AS患者血浆TNF α水平、IL 2水平均显著低于健康对照组 (P <0 0 1,P <0 0 5 ) ,IL 10水平显著高于健康对照组 (P <0 0 5 )。CD3 、CD3 CD8 T细胞百分率显著低于健康对照。CD8 HLA DR T细胞百分率均显著低于健康对照 (P <0 0 5 ) ,CD4 HLA DR T显著高于健康对照 (P <0 0 5 )。结论 :AS患者血浆低水平的TNF α、IL 2和高水平的IL 10提示其体内存在着TH1 TH2平衡的偏移 ;TH1激活程度低下 ,而TH2激活程度增强 ,细胞因子水平的改变尤以TH1细胞因子TNF α改变特别明显。AS患者在多个层面存在细胞免疫功能紊乱     

肺表面活性蛋白A基因多态性与呼吸道合胞病毒下呼吸道感染的相关性研究

目的探讨肺表面活性蛋白（SP）-A1-1101C/T和SP-A2-1649G/C位点基因多态性与呼吸道合胞病毒下呼吸道感染（RSV-LRTI）的相关性。方法应用聚合酶链反应-限制性酶切片段长度多态性（PCR-RFLP）分析法检测200例病例组和150例健康对照组2个位点的基因多态性,并进行基因型、等位基因型频率分析;采用DNA测序法进行测序分析。结果 1.病例组SP-A1-1101C/T位点TT、CT基因型频率分别为76.0%、24.0%,T、C等位基因频率分别为88.0%、12.0%;对照组TT、CT基因型频率分别为80.7%、19.3%,T、C等位基因频率分别为90.3%、9.7%,两组基因型及等位基因频率差异无统计学意义（χ2=1.088、0.953,P〉0.05）。2.病例组SP-A2-1649G/C位点CC、CG、GG基因型频率分别为41.5%、50.5%、8.0%,C、G等位基因频率分别为66.8%、33.2%;对照组CC、CG、GG基因型频率分别为43.3%、49.3%、7.4%,C、G等位基因频率分别为68.0%、32.0%,两组基因型及等位基因频率无统计学意义（χ2=0.141、0.122,P〉0.05）;但该位点基因型和等位基因在轻度和重度患儿间的差异有统计学意义（χ2=6.664、5.207,P〈0.05）,携带G等位基因的个体患重度RSV-LRTI的风险是患轻度风险的1.656倍,（OR=1.656,95%CI：1.072～2.559,P=0.023〈0.05）。结论温州地区汉族儿童存在SP-A1-1101C/T、SP-A2-1649G/C基因多态性,未发现其与RSV-LRTI疾病易感性存在关联,但携带SP-A2-1649G等位基因的个体患重度RSV-LRTI的风险是患轻度风险的1.656倍,表明G等位基因可能是影响RSV-LRTI疾病严重程度的一个候选基因。     

中西药联合应用对呼吸道合胞病毒抑制作用的研究

目的 了解病毒唑、护肺口服液及二者联合应用时对呼吸道合胞病毒(RSV)的体外抑制作用。方法 观察不同药物浓度下RSV对Hep—2细胞的致病作用。结果 病毒唑完全抑制RSV复制的最小浓度为7．80μg／ml,护肺口服液则为5．00mg／ml;两药联合应用时,完全抑制RSV复制的病毒唑和护肺口服液的最小浓度分别为减少到0．98μg／ml和0．63mg／m1,比单独用药浓度均降低了87．4％。结论 两种药物对RSV都有体外抑制作用,联合应用时效果最强。     

呼吸道合胞病毒疫苗研究动态

呼吸道合胞病毒(respiratory syneytial virus，RSV)是引起婴幼儿严重下呼吸道感染的重要病毒性病原体，广泛分布于世界各地。其发病率高，多数儿童在两岁前都感染过RSV。老年人和免疫力低下的人群中也会暴发流行。RSV感染的临床表现在不同年龄组往往不同，一般可致鼻炎、中耳炎、哮喘、支气管炎、细支气管炎和肺炎，尤其以后两种疾病最为严重，甚至可导致死亡。RSV属副黏病毒科，肺炎病毒属，病毒粒子直径约150～300nm。     

川崎病TH1/TH2功能状态的研究

川崎病(Kawasaki disease,KD)是一种急性弥漫性血管炎,婴幼儿发病多见,至今,该病病因及发病机理不明,从病人的流行病学特征推测可能与病原体感染或毒素超抗原引起免疫学异常有关.本研究通过对KD患儿急性期、恢复期PPD皮试的观察以及外周血血清IgE的变化、外周血CD4 T细胞CD30表达和外周血单个核细胞(PBMC)培养上清IL-4、IFN-γ水平的测定,了解KD急性期TH1/TH2功能平衡状态及免疫发病机理.     

乌鲁木齐地区冬春季小儿呼吸道感染者中呼吸道合胞病毒感染的研究

目的 了解乌鲁木齐地区冬春季节呼吸道感染患儿中呼吸道合胞病毒(RSV)的感染状况以及分子流行病学的基本情况.方法 研究对象为2006年11月-2007年4月于新疆维吾尔自治区人民医院儿科住院以及部分于门诊就诊,明确诊断为急性呼吸道感染的患儿,采集咽拭子280份,呼吸道分泌物112份.对全部标本采用反转录聚合酶链反应(RT-PCR)方法进行RSV及其亚型检测.随机取5份阳性标本测序,进行序列比较及同源性分析.结果 392份样本中共检出RSV阳性68份,阳性率17.3%(68/392),其中A基因型64份,占93.3%(64/68),B基因型4份,占6.7%(4/68).5株测序结果提示当地RSV与其他国家及地区代表株之间的同源性为63.1%～99.4%.进化树进一步显示存在A、B两个亚型.结论 RSV是引起2006-2007年冬春季该医院儿童急性呼吸道感染的重要病原体,以A亚型为主要流行株.

Abstract：

Objective To research the infections of respiratory syneytial virus(RSV)in children with respiratory tract inflammation and define its molecular epidemic features in Urumchi.Methods SamDles were collected from November 2006 to April 2007 in the People's General Hospital of Xinjiang Uygur Autonomous Region,including 112 respiratory secretions and 280 nasopharyngeal swabs. RSV and its subgroups were detected by nested PCR.The five positive amplicons selected randomly from all positive samples were sequenced and compared with other RSV in GenBank by BLAST and DNAStar.Results of all 392specimens.68 RSV G gene segments were tested.Among them,RSV lineage A occupied 93.3%,while B occuDied 6.7%.The identities between them were 63.1%-99.4%.Phylogenetic analysis defined that they belonged to two different clusters.Conclusion RSV was one of the important viruses leading to children's respiratory tract infections in the People's General Hospital of Xinjiang Uygur Autonomous Region during winter and spring from 2006 to 2007.RSV subtype A was the prevalent genotype in the hospital dunng this epidemics.     

呼吸道合胞病毒的分型研究

目的 了解北京地区１９９０￣１９９１年和１９９７￣１９９８年两个非连续的流行年中呼吸道合胞病毒（ＲＳＶ）Ａ、Ｂ亚型和基因型的流行情况。方法 用间接免疫荧光法（ＩＩＦ）检测ＲＳＶ阳性鼻咽分泌物（ＮＰＳ）标本或ＲＳＶ分离株,划分Ａ、Ｂ亚型。根据Ｎ基因片段的限制性酶切图型将ＲＳＶ分离株分成至少６个基因型ＮＰＩ－６ＮＰＩ,３和６属于Ｂ亚型,ＮＰ２４和５属于Ａ亚型。根据ＳＨ基因片段的核苷酸序列将Ａ亚型分离株     

TH1细胞在呼吸道合胞病毒毛细支气管炎发病机制中的作用

目的：探讨呼吸道合胞病毒（RSV）毛细支气管炎（毛支）发病中是否存在THl细胞免疫反应。方法：用ELISA法检测58例RSV毛支患儿急性期血浆IL-2含量。根据临床评分标准、供氧和住院时间长短的标准，进行严重程度分组并比较。结果：RSV毛支急性期血浆IL-2含量变化很大（0～4175ng／ml），中位数96ng／ml（4．0～530．1）。各组间比较，IL-2水平差异无显著性（均P〉0.05）；且IL-2水平与各严重因素无明显相关性（P〉0．05）。结论：TH1细胞可能不参与RSV毛支的发病机制，IL-2的改变可能系其他原因所致。     

超短波并川芎嗪雾化吸入对支气管哮喘治疗作用的研究

目的:探讨超短波加川芎嗪雾化吸入疗法对支气管哮喘的治疗作用及其作用机制。方法:选取轻、中、度支气管哮喘患者68例,随机分为超短波加川芎嗪雾化吸入治疗组(超短波组)34例和单纯川芎嗪雾化吸入治疗组(吸入疗法组)34例,疗程为2周。另选本院无吸烟史的健康体检者30例作为健康对照组。所有患者于入院第1天治疗前及治疗2周后进行症状体征评分,记录无症状天数、β2受体激动剂吸入量,测定肺功能指标,包括1秒钟用力呼气容积(FEV1),第一秒用力呼气量占用力肺活量百分比(FEV1%),最大呼气流量(PEF)。3组均抽取静脉血,采用双抗体夹心ELISA法检测IL-4和IFN-γ水平。结果:与健康对照组比较,哮喘患者血清IL-4水平升高、IFN-γ水平降低,差异均有统计学意义(P0.05)。2组患者经治疗后,临床症状评分下降,FEV1、FEV1%、PEF升高,血清IL-4水平、IL-4/IFN-γ比值降低,与治疗前比较,差异有统计学意义(P0.05);且超短波组上述各指标变化更明显,与吸入疗法组比较,差异有统计学意义。2组患者IFN-γ水平虽有升高,但与治疗前比较,差异无统计学意义(P0.05)。结论:超短波加川芎嗪雾化吸入治疗支气管哮喘有较好的临床疗效,其作用机制可能与抑制哮喘IL-4合成,从而抑制TH2细胞亚群优势反应和调节免疫平衡有关。     

Characteristics of Chlamydia trachomatis infection in hospitalized infants with lower respiratory tract infection.

BACKGROUND AND PURPOSE: To study the epidemiology, presentation and laboratory findings of Chlamydia trachomatis pneumonia in hospitalized infants younger than 6 months. METHODS: Between January 2001 and December 2005, infants younger than 6 months admitted to the children's medical center of Taipei Veterans General Hospital with the diagnosis of acute bronchiolitis, bronchopneumonia or pneumonia were prospectively studied. Chest radiograph findings were reviewed in all patients. Basic laboratory examinations performed included white blood cell count and eosinophil count. C. trachomatis was detected via enzyme-linked immunosorbent assay antigen test and the titers of immunoglobulin G and immunoglobulin M by indirect immunoperoxidase assay. RESULTS: A total of 60 infants, 32 males and 28 females, were included. C. trachomatis infection was detected in 30% of patients (18/60). The median age was 2.5 months (range, birth to 6 months). Fever was not detected in 72% of patients (13/18). Only 22% (4/18) of these patients had the characteristic staccato cough. The mean duration of symptoms before admission was 8 days (range, 1 day to 2 months). Rhinorrhea was a prodromal symptom in 67% (12/18) of patients, with a mean pre-onset duration of 7 days (range, 1 to 14 days). Eighty three percent (15/18) of the patients had tachypnea, with a mean duration of 3.2 days (range, 1 to 7 days). Conjunctivitis was noted before admission in 6 patients (33%). Only peripheral eosinophils showed statistically significant difference between Chlamydia-positive and -negative disease (p=0.046), and may be clinically useful in cases of suspected C. trachomatis infection. Mixed infection with other pathogens including adenovirus, respiratory syncytial virus, Mycoplasma pneumoniae, cytomegalovirus and Streptococcus pneumoniae was found in 27% (5/18) of patients. CONCLUSIONS: C. trachomatis is not infrequent and plays an important role in infants younger than 6 months old hospitalized due to lower respiratory tract infection.     

Different patterns of cytokine induction in cultures of respiratory syncytial (RS) virus-specific human TH cell lines following stimulation with RS virus and RS virus proteins

Human peripheral blood mononuclear cell (PBMC) proliferative responses to live respiratory syncytial (RS) virus, formalin-inactivated RS (FI-RS) virus, RS virus F (fusion) protein, and RS virus G (attachment) protein were assessed. All donors responded to challenge with whole RS virus antigens and F and G proteins. F protein responses elicited higher levels of response than equivalent concentrations of G protein in nine out of ten adult RS-seropositive donors. Stimulation of PBMC induced low levels of interleukin 2 (IL-2), interferon γ (IFN-γ), IL-4, and IL-10 production. Human RS virus-specific T cell lines were generated from peripheral blood cultures following in vitro stimulation with RS virus antigens. All lines generated were shown to be MHC class II restricted. Characterisation of the lines was carried out by determining the levels of IL-2, IFN-γ, IL-4, and IL-10 in culture supernatants. T cell lines enriched for RS virus-specific cells provided a more sensitive system than PBMC cultures for the detection of cytokines. The pattern of cytokine production varied for the individual lines, and the detection of T_H1 and T_H2 cytokines was dependent on the nature of the stimulating RS virus antigen. Live RS virus induced a T_H1 pattern of cytokines (IL-2 and IFN-γ), whereas FI-RS virus induced the production of both T_H1 and T_H2 cytokines. In addition, T_H lines specific for individual RS virus proteins produced different cytokine profiles. F protein-specific lines generated T_H1-type cytokines (IL-2 and IFN-γ), whereas G protein-specific lines generated T_H2-type cytokines (IL-4 and IL-10). © 1996 Wiley-Liss, Inc.     

Influence of respiratory syncytial virus infection on cytokine and inflammatory responses in allergic mice

BACKGROUND: Th2 lymphocyte responses are associated with inflammation and disease during allergic responses. Exposure to particular environmental factors during the expression of allergy could result in more pronounced Th2-like immune responses and more severe disease. One factor might be a respiratory virus infection. OBJECTIVE: The aim of our study was to investigate the influence of respiratory syncytial virus (RSV) infection on the expression of ovalbumin (OVA)-induced allergy in BALB/c mice. METHODS: We determined OVA-specific IgE in serum, cytokine profiles and histopathological lesions in lungs of OVA-allergic mice after RSV infection. RESULTS: OVA sensitization and challenge induced OVA-specific IgE in serum, Th2 cytokine mRNA expression, and mononuclear and eosinophilic inflammation in the lungs. RSV inoculation during the challenge period enhanced OVA-induced IL-4 and IL-5 mRNA expression in lung tissue. RSV further enhanced the OVA-induced hypertrophy of mucous cells and eosinophilic infiltration in lung tissue. Surprisingly, RSV infection decreased Th2 cytokine secretion and eosinophilic influx in bronchoalveolar lavage of OVA-allergic mice. Because inactivated RSV did not influence these responses, replication of RSV appeared essential for the modification of OVA-induced Th2 cytokine expression. RSV did not change OVA-specific IgE levels in serum. Furthermore, the RSV-induced IL-12 mRNA expression in lung tissue of OVA-allergic mice was diminished, but IFN-gamma mRNA expression was not affected. CONCLUSION: RSV infection enhanced particular OVA-induced Th2 cytokine mRNA responses and pulmonary lesions in allergic mice and thus aggravated allergic respiratory disease.     

Lack of evidence ofChlamydia pneumoniae infection in infants with acute lower respiratory tract disease

In order to determine whether there is serologic evidence ofChlamydia pneumoniae infection in young infants with acute lower respiratory tract infection, serum samples from 86 subjects aged less than 6 months were assayed for IgG and IgM antibodies toChlamydia pneumoniae using a microimmunofluorescence method. Infants hospitalized in Toronto, Canada, were enrolled between 15 March 1991 and 15 March 1992. No patient had infection determined by the serologic results. IgG antibody was detected at low concentrations in 32 patients, with an inverse relationship between titer and chronological age. In our setting,Chlamydia pneumoniae does not appear to be an important lower respiratory pathogen in young infants.     

长沙地区呼吸道感染儿童Saffold心肌炎病毒的调查

目的了解长沙地区Saffold病毒（以下简称为SAFV）在儿童呼吸道感染中的流行情况,探讨其与儿童呼吸道感染的相关性。方法选取湖南省人民医院儿科医学中心2007年11月至2008年10月间643名因呼吸道感染住院儿童的鼻咽抽吸物。采用实时荧光定量聚合酶链式反应（Realtime．PCR）方法扩增SAFV的5UTR的基因片段,并且统计分析临床资料。结果643份样本中共检测出SAFV阳性67份,阳性检出率为10．42％（67／643）,5岁以上未检测出该病毒。31例患迁延性肺炎和慢性肺炎的患儿标本检出SAFV8例（25．81％）,差异有统计学意义。结论本研究表明长沙地区下呼吸道感染住院儿童存在SAFV感染;SAFV可能与下呼吸道感染及病程迁延相关。     

Attenuated interleukin-8/leukocyte immunoresponse in preterm infants compared with term infants hospitalized with respiratory syncytial virus bronchiolitis: a pilot study

Decreased transplacental transfer of antibodies and altered immunoresponsiveness may place preterm (PT) infants at higher risk for serious consequences from respiratory syncytial virus (RSV) bronchiolitis. We hypothesize that among infants hospitalized with RSV bronchiolitis, immune response in PT infants may be different when compared with that of term infants. Nasal-wash samples were collected from 11 PT (<37 weeks of gestation) and 13 term infants (≥37 weeks of gestation) hospitalized with RSV bronchiolitis. Severity of illness (clinical score [CS]), admission peripheral oxygen saturation, and days subjects required supplemental oxygen were compared. Nasal-wash leukocyte count as well as cytokines for interleukin (IL)-8, IL-4, and interferon-γ (IFN-γ) were assayed. No significant differences in CS, admission SaO(2), and O(2) days were seen between PT and term infants. Nasal-wash leukocyte counts and IL-8 levels were higher in term infants compared with PT and correlated with severity (higher CS) in term (p < 0.05) but not in PT (p > 0.05) infants. IL-4 and IFN-γ levels did not differ between the 2 groups (p > 0.05). PT infants hospitalized with RSV bronchiolitis have lower nasal-wash leukocyte counts and a less robust IL-8 response than term infants, and only in term infants did IL-8 levels correlate with clinical disease severity.