Multivalent DNA vaccine protects mice against pulmonary infection caused by Pseudomonas aeruginosa

For efficacious vaccine development against Pseudomonas aeruginosa (P. aeruginosa), the immunogenicity of multivalent DNA vaccine was evaluated. Three different plasmids each targeting a fusion of outer membrane proteins (OprF/OprI), a protein regulating type III secretion system (PcrV), or an appendage (PilA) were prepared and mice were immunized with single (monovalent) or a combination of these plasmids (multivalent) via intramuscular electroporation (imEPT) or gene gun. Immunization with multivalent DNA vaccine via imEPT induced the most potent protection against lethal pneumonia. Although the serum levels of IgG binding to whole bacteria cells were comparable between groups, the strongest immune protection was associated with the serum levels of Th1-dominated multivalent IgG, the bronchoalveolar levels of macrophage inflammatory protein 2 (MIP-2) and IFN-gamma, and the number of neutrophils and macrophages in the bronchoalveolar lavage following intranasal challenge. These results implied the possible clinical application of multivalent DNA vaccine against P. aeruginosa.     

Intranasal Protollin/F1-V vaccine elicits respiratory and serum antibody responses and protects mice against lethal aerosolized plague infection

F1-V is a recombinant plague antigen comprising the capsular (F1) and virulence-associated (V) proteins. Given intramuscularly with Alhydrogel, it protects mice against challenge, but is less effective in non-human primates against high-dose aerosolized Yersinia pestis challenge, perhaps because it fails to induce respiratory immunity. Intranasal immunization of mice with F1-V formulated with a Proteosome-based adjuvant (Protollin), elicited high titers of specific IgA in lungs whereas intranasal F1-V alone or intramuscular Alhydrogel-adsorbed F1-V did not. The Protollin-adjuvanted F1-V vaccine also induced high serum titers of specific IgG, comparable to those induced by intramuscular Alhydrogel-adsorbed F1-V. Mice immunized intranasally with Protollin-F1-V were 100% protected against aerosol challenge with 170 LD50 of Y. pestis and 80% against 255 LD50.     

铜绿假单胞菌生物膜致豚鼠下呼吸道感染分析

目的探讨铜绿假单胞菌生物膜致病性。方法 60只豚鼠随机分为生物膜组、浮游菌组和对照组,行气管切开术后分别植入生物膜细菌、浮游态细菌及生理盐水包被的硅胶管,15 d后收集支气管肺泡灌洗液(BALF)、支气管及肺组织,测量活菌数,分离细菌并测定生物膜形成能力,观察组织形态改变。结果生物膜组豚鼠下呼吸道慢性感染发生率为66.7%,明显高于浮游菌组(P<0.01);生物膜组豚鼠支气管及肺组织可见肺泡腔内纤维渗出,间隔炎性细胞浸润,纤毛上皮增生,黏膜下淋巴细胞浸润;生物膜组豚鼠BALF及肺组织中细菌总数分别为(7.45±0.23)×10³ cfu/mL和(6.78±0.36)×10³ cfu/g,并分离出能够形成生物膜的铜绿假单胞菌。结论铜绿假单胞菌生物膜是下呼吸道慢性感染的高危因素之一。     

Intranasal immunisation with recombinant adenovirus vaccines protects against a lethal challenge with pneumonia virus of mice

Pneumonia virus of mice (PVM) infection of BALB/c mice induces bronchiolitis leading to a fatal pneumonia in a dose-dependent manner, closely paralleling the development of severe disease during human respiratory syncytial virus infection in man, and is thus a recognised model in which to study the pathogenesis of pneumoviruses. This model system was used to investigate delivery of the internal structural proteins of PVM as a potential vaccination strategy to protect against pneumovirus disease. Replication-deficient recombinant human adenovirus serotype 5 (rAd5) vectors were constructed that expressed the M or N gene of PVM pathogenic strain J3666. Intranasal delivery of these rAd5 vectors gave protection against a lethal challenge dose of PVM in three different mouse strains, and protection lasted for at least 20 weeks post-immunisation. Whilst the PVM-specific antibody response in such animals was weak and inconsistent, rAd5N primed a strong PVM-specific CD8⁺ T cell response and, to a lesser extent, a CD4⁺ T cell response. These findings suggest that T-cell responses may be more important than serum IgG in the observed protection induced by rAd5N.     

ESA和STAg鼻内免疫小鼠抗弓形虫感染作用

目的 观察弓形虫速殖子排泄一分泌抗原(excreted/secreted antigen,ESA)和可溶性速殖子抗原(solubletachyzoite antigen,STAg)鼻内免疫小鼠诱导的抗弓形虫感染作用。方法 BALB/c小鼠64只随机分为4组,每组16只,分别用磷酸盐缓冲液(PBS)(对照组)20μl/只、体外排泄-分泌抗原(excreted/secreted antigen in vitro,ESAv)20μg/只、腹腔排泄-分泌抗原(excreted/secreted antigen in mice,ESAm)20μg/只和STAg20μg/只滴鼻免疫小鼠2次,间隔14 d。末次免疫后14 d每组处死8只小鼠,ELISA法检测血清IgG和小肠冲洗液sIgA。每组剩余8只小鼠用RH株弓形虫速殖子1×10⁴个/只灌胃攻击,记录小鼠健康情况。攻击后30 d处死小鼠,计数脾、脑组织内弓形虫虫荷(速殖子数)。结果 ESAm组小鼠于2次免疫后出现轻微竖毛、倦怠等症状,其他各组小鼠健康状况良好。免疫后14 d,各抗原组血清IgG水平均明显高于对照组(P<0.001);ESAv(P<0.05)、ESAm(P<0.001)和STAg(P<0.001)组肠液sIgA水平明显高于对照组,EsAm(P<0.001)和sTAg(P<0.05)组高于EsAv组。弓形虫攻虫后:30 d,各抗原组小鼠脾、脑组织内虫荷显著低于对照组(P<0.01),ESAv、ESAm和sTAg组脾内速殖子减虫率分别为49.2%,49.52%和51.94%,脑内减虫率分别为46.83%,50.81%和51.18%。结论 ESAv、ESAm和STAg鼻内免疫均能产生抗弓形虫感染的部分保护,但ESAm可能对机体有毒副作用,不适宜直接鼻内免疫。     

Intranasal IFN-gamma gene transfer protects BALB/c mice against respiratory syncytial virus infection.

Respiratory syncytial virus (RSV) is a major respiratory pathogen in infants, young children and the elderly and causes severe bronchiolitis and asthma. In an effort to develop a preventive IFN-gamma therapy against RSV infection, an intranasal gene transfer strategy was utilized. Intranasal administration of a plasmid expressing the IFN-gamma cDNA (pIFN-gamma) resulted in the expression of IFN-gamma in murine lungs and decreased RSV replication. The mice administered with pIFN-gamma and then infected with RSV exhibited a significant decrease in broncho-alveolar lavage lymphocyte and neutrophil counts. A significant reduction in epithelial cell damage, infiltration of mononuclear cells in the peribronchiolar and perivascular regions, and thickening of the septa was observed in the lungs of mice treated with pIFN-gamma when compared to controls. These results suggest that intranasal IFN-gamma gene transfer results in decreased RSV replication and pulmonary inflammation and may be useful against RSV infection.     

比阿培南治疗下呼吸道铜绿假单胞菌感染的疗效

目的评估比阿培南治疗铜绿假单胞菌(PAE)下呼吸道感染临床疗效和安全性。方法 88例下呼吸道PAE感染患者随机分为治疗组与对照组,分别使用比阿培南和亚胺培南/西司他丁治疗,疗程均为10～14d。结果治疗组总有效率为88.6%,细菌清除率为90.9%,均高于对照组的70.5%、75.0%,两组不良反应发生率较低。结论比阿培南治疗PAE下呼吸道感染临床疗效可靠且安全。     

Identification of patients with Pseudomonas aeruginosa respiratory tract infections at greatest risk of infection with carbapenem-resistant isolates.

OBJECTIVE: To create a clinical tool based on institution-specific risk factors to estimate the probability of carbapenem resistance among Pseudomonas aeruginosa isolates obtained from infected patients. By better estimating the probability of carbapenem resistance on the basis of patient-specific factors, clinicians can refine their empirical therapy for P. aeruginosa infections and potentially maximize clinical outcomes by increasing the likelihood of appropriate empirical antimicrobial therapy. DESIGN: A retrospective, cross-sectional study. SETTING: Tertiary care academic hospital. PATIENTS: All adult inpatients who had a respiratory tract infection due to P. aeruginosa between January 2001 and June 2005. INTERVENTION: Data on demographic characteristics, antibiotic history, and microbiology were collected. Log-binomial regression was employed to identify predictors of carbapenem resistance among P. aeruginosa isolates and to devise the clinical prediction tool. RESULTS: Among 351 patients with P. aeruginosa infection, 44% were infected with carbapenem-resistant P. aeruginosa strains. Independent predictors of carbapenem resistance were prior receipt of mechanical ventilation for 11 days or more, prior exposure to fluoroquinolones for 3 days or more, and prior exposure to carbapenems for 3 days or more. CONCLUSIONS: With carbapenem resistance rates among P. aeruginosa isolates on the rise at our institution, the challenge was to identify patients for whom carbapenems would remain an effective empirical agent, as well as the patients at greatest risk for infection with carbapenem-resistant strains. The clinical prediction tool accurately estimated carbapenem resistance among this risk-stratified cross-sectional study of patients with P. aeruginosa infection. This tool may be an effective way for clinicians to refine their selection of empirical antibiotic therapy and to maximize clinical outcomes by increasing the likelihood of appropriate antibiotic treatment.     

Safety and effectiveness against respiratory tract infections for pneumococcal conjugate vaccine co-administered with routine vaccine combinations

Streptococcus pneumoniae is a major cause of bacterial pneumonia and other respiratory tract infections (RTI) in children. The heptavalent conjugated pneumococcal vaccine (PCV7) is offering a promising strategy against pneumococcal disease in children younger than 2 years. In this prospective epidemiological study in Germany, children between 2 and 6 months of age received in a 3:1 ratio a routine childhood vaccine combination with or without PCV7 according to a four-dose schedule. Five thousand nine hundred and eighty-four children were evaluable 1 year after the booster dose. Due to German guidelines children with underlying medical conditions were preferentially included into the PCV7 group and hence 66% of the children in the PCV7 group had at least one medical risk factor and 40% were preterm born compared to 18% and 6% in the control group. Overall PCV7 reduced respiratory tract infections by 10.5% (95% CI: 2.9-17.3%) and clinically diagnosed pneumonia by 6.3% (95% CI: -15.9 to 23.7%) in this unbalanced situation. In a propensity score matched pair analysis controlling for risk factors, effectiveness of PCV7 against pneumonia was 24.8% (95% CI: 0.9-43.1%). In children with at least one medical risk factor vaccine effectiveness against pneumonia was 38.4% (95% CI: 10.7-55.9%) compared to 10.9% (95% CI: -20.2 to 33.9%) without a risk factor. In preterm and term born children, PCV7 was well tolerated when simultaneously administered with widely used hexavalent routine vaccine combinations. The results demonstrate that PCV7 is safe and effective against RTI in preterm children and in children with comorbidities stressing the benefit of pneumococcal conjugate vaccine in these children at high risk for pneumococcal disease.     

煤工尘肺患者下呼吸道产金属内酰胺酶铜绿假单胞菌感染状况

目的了解煤工尘肺患者下呼吸道产金属内酰胺酶的铜绿假单胞菌(PA)的感染状况及其耐药特性。方法分离下呼吸道感染的煤工尘肺患者痰液标本中的PA，根据药敏试验，筛选可疑产金属内酰胺酶PA，最后依据2-巯基丙酸双纸片法鉴定产金属内酰胺酶PA。结果40株PA中共筛选出10株可疑PA，最终确定产金属内酰胺酶PA6株。这些菌株均有很强的耐药性，对亚胺培南、头孢菌素、含酶抑制剂类抗菌药物全部耐药；对阿米卡星、环丙沙星、左氧氟沙星、庆大霉素等药物部分耐药。产金属内酰胺酶PA的耐药性远强于不产金属内酰胺酶的PA。结论产金属内酰胺酶PA的耐药性很强，应加强煤工尘肺患者产金属内酰胺酶PA的检测，以利于指导治疗和控制感染。     

Intranasal vaccination of neonatal mice with polysaccharide conjugate vaccine for protection against pneumococcal otitis media

Streptococcus pneumoniae is the leading bacterial cause of acute otitis media (OM) in young children, and can often produce invasive disease. Typical intramuscular routes of vaccination are poorly protective against development of OM. In the present study, we intranasally (i.n.) inoculated neonatal 1-week-old mice with pneumococcal polysaccharide conjugate vaccine using IL-12 as a mucosal adjuvant. The protective efficacy of this treatment was tested by challenging immunized infant (3-week-old) mice with bacteria to induce OM and invasive disease. i.n. vaccination was found to enhance levels of specific antibodies in middle ear (ME) washes and sera from wild-type (but not IFN-γ^−/−) mice. Immunization in the presence of IL-12 resulted in enhanced clearance of S. pneumoniae from the ME. Opsonization of bacteria with ME wash fluids or sera from immunized mice caused increased bacterial clearance from the ME of naïve mice. In addition, immunized mice demonstrated 89% survival after OM-induced invasive pneumococcal infection, compared to 22% survival in unvaccinated mice. These results indicate that i.n. vaccination of neonatal mice in the presence of IL-12 is able to enhance IFN-γ dependent ME mucosal and systemic immune responses to pneumococci and efficiently protect against both OM and invasive infection.     

An X-ray inactivated vaccine against Pseudomonas aeruginosa Keratitis in mice

Pseudomonas aeruginosa (P. aeruginosa) is one of the most prevalent pathogens of bacterial keratitis. Bacterial keratitis is a major cause of blindness worldwide. The rising incidence of multidrug resistance of P. aeruginosa precludes treatment with conventional antibiotics. Herein, we evaluated the protective efficiency and explored the possible underlying mechanism of an X-ray inactivated vaccine (XPa) using a murine P. aeruginosa keratitis model. Mice immunized with XPa exhibit reduced corneal bacterial loads and pathology scores. XPa vaccination induced corneal macrophage polarization toward M2, averting an excessive inflammatory reaction. Furthermore, histological observations indicated that XPa vaccination suppressed corneal fibroblast activation and prevented irreversible visual impairment. The potency of XPa against keratitis highlights its potential utility as an effective and promising vaccine candidate for P. aeruginosa.     

Discovery of a vaccine antigen that protects mice from Chlamydia pneumoniae infection

Chlamydiae are atypical intracellular bacteria that infect via mucosal surfaces causing, for example, trachoma, pneumonia, cervicitis, urethritis and infertility. Existing antibiotics are only partially effective and no vaccines are available. Using surface expressed or secreted proteins previously identified by genomics and proteomics we tested five as vaccines against intranasal challenge with Chlamydia pneumoniae. One antigen, LcrE, induced CD4+ and CD8+ T cell activation, type 1 cytokine secretion and neutralising antibodies and was completely effective in eliminating infection. Such antigens are highly conserved and essential to all Chlamydial species. The discovery of an effective vaccine for Chlamydiae pneumoniae has potential wide benefits for human health.     

慢性阻塞性肺疾病患者下呼吸道感染铜绿假单胞菌耐药性分析

目的调查慢性阻塞性肺疾病(COPD)患者下呼吸道感染铜绿假单胞菌的耐药性,为临床治疗提供参考。方法采用法国生物梅里埃公司ATB-Expression分析仪进行细菌鉴定,K-B法进行体外药敏试验。结果共检出铜绿假单胞菌113株,铜绿假单胞菌对磺胺甲噁唑/甲氧苄啶、氨苄西林/舒巴坦、替卡西林、头孢噻肟、头孢曲松、哌拉西林、庆大霉素、环丙沙星、头孢他啶、头孢吡肟、阿米卡星的耐药率分别为95.6%、81.4%、64.4%、62.8%、56.6%、47.8%、40.7%、40.7%、36.3%、30.1%、23.0%,对亚胺培南耐药率最低,为9.7%。结论 COPD患者感染铜绿假单胞菌耐药性十分严峻,应加强病原菌耐药性监测,合理使用抗菌药物。     

下呼吸道感染的铜绿假单胞菌耐药性分析

目的分析下呼吸道感染的铜绿假单胞菌对常用抗生素的耐药特征,为临床治疗提供依据。方法用ATB自动化细菌鉴定及药敏分析系统对菌落进行鉴定及药敏,对检出的铜绿假单胞菌的药敏结果进行统计分析。结果2007年1月~2008年12月共分离出251株铜绿假单胞菌,占同期所有呼吸道标本分离病原菌总数的15.6%;铜绿假单胞菌对多粘菌素E的耐药率最低(8.8%)、对亚胺培南、美罗培南、阿米卡星、妥布霉素的耐药率均40.0%,对替卡西林的耐药率最高(59.0%)。结论治疗铜绿假单胞菌引起的下呼吸道感染应密切结合药敏试验,合理应用抗生素,对防治铜绿假单胞菌的耐药及传播,控制院内感染具有重要意义。     

呼吸道分泌物分离铜绿假单胞菌IMP、 TEM基因携带情况及毒力特征

目的 探究呼吸道分泌物标本中铜绿假单胞菌IMP、TEM基因携带情况,并对其毒力特征进行分析。方法 收集2017年10月-2020年10月海口市中医医院呼吸道分泌物分离的铜绿假单胞菌83株,分析其临床分布特征及对临床常用抗菌药物的耐药性,检测IMP、TEM基因及毒力基因携带情况。结果 83株铜绿假单胞菌共检出IMP基因阳性76株(91.57%),TEM基因阳性67株(80.72%),不同疾病类型IMP、TEM基因检测结果比较差异有统计学意义(P<0.05);与24 h药敏结果比较,48 h铜绿假单胞菌对亚胺培南、阿米卡星、妥布霉素、头孢他啶、头孢吡肟、环丙沙星和美罗培南的耐药率均升高(P<0.05);携带IMP⁺/TEM⁺基因型的菌株对亚胺培南和美罗培南的耐药率均高于携带非IMP⁺/TEM⁺型菌株(P<0.05); 78株(93.98%)检出携带exoS或exoU基因,≥60岁患者exoS基因检出率高于exoU基因(P<0.05),携带exoU基因型的铜绿假单胞菌对左氧氟沙星、...     

Intranasal immunisation of mice with liposomes containing recombinant meningococcal OpaB and OpaJ proteins

The opacity (Opa) proteins of Neisseria meningitidis are outer membrane proteins involved in adhesion and invasion of host epithelial cells and are therefore expected to play an important role in colonisation of the nasopharynx. The majority of meningococcal Opa proteins bind to members of the CEACAM receptor family, such as CEA. Blocking of the Opa-CEACAM interaction by mucosal anti-Opa antibodies could thus constitute an important protective mechanism for novel meningococcal vaccines. In this study we analysed the specific anti-Opa antibody responses after intranasal immunisation of mice with liposomes containing purified and native OpaB (recognising the CEA receptor) and OpaJ (no affinity for CEA) proteins. These antigens were combined with or without one of three different adjuvants, i.e. purified meningococcal LPS, monophosphoryl lipid A (MPL) or the B-subunit of Escherichia coli heat-labile enterotoxin (EtxB). After intranasal immunisation with any of these formulations, anti-Opa IgA antibodies were found in nasal lavages and in some cases anti-Opa IgA and IgG antibodies were also found in lung lavages. With OpaJ but not OpaB, significant bactericidal serum titres were obtained. Of the different adjuvants used, meningococcal LPS gave the strongest overall immune response. Non-adjuvated liposomal Opa formulations were poorly immunogenic. No differences were found between the immune response in transgenic mice expressing the CEA-receptor and non-transgenic mice, showing that the CEA-Opa interaction does not influence the antibody response.     

氨溴索雾化吸入治疗铜绿假单胞菌下呼吸道感染的临床研究

目的 评价氨溴索雾化吸入治疗铜绿假单胞菌(PAE)下呼吸道感染的临床效果及安全性.方法 将41例PAE下呼吸道感染的患者随机分为两组,对照组选择对PAE敏感的哌拉西林/他唑巴坦、左氧氟沙星联合治疗,试验组在对照组治疗的基础上加用氨溴索雾化吸入,疗程均为10～14 d.结果 试验组痊愈率为65.0％,有效率为85.0％;对照组痊愈率为33.3％,有效率为66.7％,两组痊愈率差异有统计学意义(P＜0.05),有效率差异无统计学意义;试验组及对照组细菌清除率分别为75.0％和42.9％,差异有统计学意义(P＜0.05).结论 氨溴索雾化吸入辅助治疗PAE下呼吸道感染,有助于清除PAE,有可能成为理想的治疗方案.     

呼吸病区铜绿假单胞菌医院感染的流行病学研究

为了解铜绿假单胞菌医院感染的流行病学。方法 用血清型和抗菌谱联合分型方法，对患者分离株和环境分离株从检出时间，地点或部位进行动态分析。结果 ２１２３份样本共检出铜绿假单胞菌１７６株，分离率为０．８％＿５７．１％，患者之间，患者与环境及医护人员检出的铜绿假单胞菌未见有关联。