The capsular group B meningococcal vaccine, 4CMenB: clinical experience and potential efficacy

Introduction: Capsular group B meningococcal disease is a leading cause of childhood meningitis and septicaemia. Up to 10% of sufferers die, and sequelae remain in > 30% of survivors. A vaccine, four component meningococcal group B (4CMenB), designed with the aim to induce broad coverage against this highly variable bacterium, has been licensed in countries including in the European Union, Canada and Australia.

Areas covered: Immunogenicity and safety data, published in peer-reviewed literature between 2004 and 2014, are presented in the context of the recent recommendation for the use of the vaccine in infants in the UK.

Expert opinion: 4CMenB induces significant reactogenicity when administered with routine infant vaccines, in particular with respect to fever rates. Fevers can be somewhat reduced using paracetamol. The efficacy of the vaccine is unknown but has been extrapolated from effectiveness data obtained from use of one of its components in New Zealand, immunogenicity data from clinical trials and estimation of coverage from in vitro studies. These data suggest that the vaccine will prevent a proportion of invasive meningococcal disease cases in infants and young children. Implementation and well-planned post-marketing surveillance will address uncertainties over field effectiveness.     

人巨细胞病毒gB基因的构建、表达及鉴定

目的构建人巨细胞病毒（HCMV）gB基因,并对pET28a／gB重组质粒进行诱导表达,鉴定表达的目的蛋白。方法根据Genebank中HCMV核苷酸序列设计引物,并在引物的5’、3’端分剐加入BarnHI、EcoRI限制性内切酶位点。特异性扩增gB编码基因片段,同时构建舍HCMVgB编码基因的原核表达载体,对重组质粒进行诱导表达,用间接酶联免疫吸附测定（ELISA）法对纯化的Ni／gB融合蛋白的灵敏度和特异度等生物活性进行鉴定,灵敏度可达95％,特异度达96．7％。结果目的蛋白经诱导后表达于上清液中,经鉴定,目的蛋白保留了天然蛋白原有的生物活性。结论Ni／gB融合蛋白的获得,为研制以重组蛋白代替传统全病毒作为检测抗原的新型HCMV特异性免疫学检测试剂盒奠定了基础。     

Role of angiotensin receptor blockers in diabetes: implications of recent clinical trials

Hypertension is a comorbidity of Type 2 diabetes, and blood pressure lowering has been shown to reduce cardiovascular (CV) and renal disease progression in this population. Angiotensin-converting enzyme (ACE)-inhibitors have demonstrated reduction in CV mortality and myocardial infarction, stroke, and heart failure in patients with diabetes. Evidence suggests that angiotensin receptor blockers (ARBs) have similar CV protective effects, particularly in patients post-myocardial infarction and in those with heart failure, and their renoprotective effects have reduced proteinuria in patients with or without diabetes. In addition, ARBs have been shown to reduce diabetic nephropathy and complications related to nephropathy. The Ongoing Telmisartan Alone and in Combination with Ramipril Global Endpoint trial (ONTARGET) is the first trial to demonstrate that the ARB, telmisartan, is as effective as the ACE-inhibitor, ramipril, in CV protection in a high-risk, ACE-tolerant population. Whether all ARBs are equally cardioprotective is uncertain. Data indicate that the beneficial effects of telmisartan may be drug specific rather than constitute a ‘class effect.’     

Tuberculosis subunit vaccines: from basic science to clinical testing

More than 80 years after the introduction of Bacillus Calmette–GuÉrin, the first tuberculosis vaccine, new vaccines for tuberculosis are finally in clinical trials. The selection of antigens on which new subunit vaccines are based represent the first fulfilment of the promise of proteomics and ?genomics, and the delivery systems for these antigens are likewise the first fruits of the improved understanding of how the host immune system recognizes pathogens. However, clinical trials are still at Phase I and there remain formidable obstacles to the registration of the first new TB vaccines. Here the authors review the vaccines in clinical trials and discuss the different approaches they take to stimulating immunity to Mycobacterium tuberculosis infection, focusing on recombinant subunit vaccines. The challenges that confront these approaches and how they are being addressed are then discussed.     

Transfusion-transmitted cytomegalovirus: lessons from a murine model

Transfusion-transmitted cytomegalovirus (CMV) infection (TT-CMV) continues to complicate blood transfusion therapy, which can lead to severe morbidity or mortality in immunocompromised or immuno-immature recipients. The biological mechanisms that underlie TT-CMV (eg, viral latency in donor monocytes or stimulatory signals in the transfusion recipient leading to cytomegalovirus reactivation) are difficult to study in humans, but can be addressed in animal models. In this review, we discuss a mouse blood transfusion model, which can be used to investigate these issues as well as to validate methods to prevent TT-CMV in at-risk patients.     

Nosocomial MRSA pneumonia: data from recent clinical trials

MRSA infections, especially pneumonia have been associated with considerable morbidity and mortality and the management of MRSA infections is considered as an issue of high priority for scientific societies. Many studies which have been published during the last 10 years have provided evidence for MRSA pneumonia epidemiology, diagnosis and treatment. The main regime of antibiotic treatment recommended for MRSA pneumonia is either vancomycin or linezolid. Despite its pK/pD superiority over vancomycin, linezolid has to date failed to show clear advantage over vancomycin in recent clinical trials.     

Erythropoietin and organ protection: lessons from negative clinical trials

In a previous issue of Critical Care, Lorente and colleagues reported the results of a prospective observational study aiming at evaluating the effect of continuous control of cuff pressure (P_cuff ) on the incidence of ventilator-associated pneumonia (VAP). The results suggest a beneficial impact of this intervention on VAP prevention, which is in line with the results of a recent randomized controlled study. However, another randomized controlled study found no significant impact of continuous control of P_cuff on VAP incidence. Several differences regarding the device used to control P_cuff, study population, and design might explain the different reported results. Future randomized multicenter studies are needed to confirm the beneficial effect of continuous control of P_cuff on VAP incidence. Furthermore, the efficiency and cost-effectiveness of different available devices should be compared. Meanwhile, given the single-center design and the limitations of the available studies, no strong recommendation can be made regarding continuous control of P_cuff as a preventive measure of VAP.     

流式细胞术检测分析人巨细胞病毒核酸疫苗诱导宿主细胞免疫效应

目的探讨人巨细胞病毒(HCMV)pp65核酸疫苗对宿主细胞免疫功能的诱导效应。方法用自行构建的含HCMVpp65基因的重组质粒免疫小鼠,用流式细胞仪检测免疫小鼠脾脏T淋巴细胞亚群的变化以及CD8 T细胞分泌干扰素γ(IFN-γ)和白细胞介素(IL)-4的情况,并以四甲基偶氮唑盐(MTT)增殖试验作补充验证。结果接种重组质粒组与仅接种空质粒或生理盐水对照组小鼠的免疫效应不同,表现为CD8 T细胞百分率增加(P<0.05),分泌细胞因子IFN-γ和IL-4的CD8 T细胞百分率亦增高(P<0.05),两者的平均荧光强度值增高更为显著(P<0.05)。免疫小鼠的脾脏T细胞经HCMVpp65蛋白刺激后,实验组的刺激指数(SI)较对照组明显增高(P<0.05)。结论HCMVpp65核酸疫苗接种可诱导宿主的细胞免疫反应,倾向于表现为细胞毒性T细胞(Tc)1和Tc2的混合应答以及脾脏T细胞的增殖效应。     

Regulatory challenges: lessons from recent West Nile virus trials in the United States

Delays in research on emerging infections could deprive the public of appropriate therapies. This report describes challenges encountered in implementing two multicenter protocols of West Nile virus (WNV) infections in the United States during 2003. Protocol development times, federal regulatory approvals, and local Institutional Review Boards (IRB) approvals were compiled. Twenty eight institutions participated in a natural history study and 27 in a therapeutic trial of WNV developed through the National Institute of Allergy and Infectious Disease Collaborative Antiviral Study Group (CASG). The CASG compiled protocol development times, federal regulatory approvals, and local IRB approvals. Additional information on the local IRB process was obtained by survey of the investigators. Because of the lengthy development and approval process, protocols were distributed after the start of the epidemic season, most sites were unable to enroll subjects at the peak of the season, and a number of sites lacked IRB approval at the end of the season.     

Development of a quadriplex polymerase chain reaction for human cytomegalovirus detection

The development of a quadriplex PCR method with amplification of HCMV in a single‐step procedure using primers taken from four different regions of the viral genome is described. Different concentrations of dNTPs and MgCl₂ were assayed in order to optimize the constitution of the buffer for the multiplex PCR. The specificity of the PCR was tested with 100ng, 10ng, and 1ng of genomic MRC‐5 cell DNA infected with CMV in the presence of 10μg of uninfected MRC‐5 cell DNA. The sensitivity of the PCR was evaluated by the amplification of various amounts (100ng, 10ng, 1ng, and 0.1ng) of genomic MRC‐5 cell DNA infected with CMV. The specificity and sensitivity assays were performed for each pair of primers and for the combined four primer pairs in the multiplex PCR. CMV was consistently detected from 10ng of genomic MRC‐5 cell DNA with each primer pair. When all four sets of primers were combined in a single reaction tube, the sensitivity of the assay was equivalent to 10ng of genomic MRC‐5 cell DNA, whereas amplification from 1ng genomic MRC‐5 cell DNA produced only a subset of the amplimers. By amplifying four target‐sequences of HCMV simultaneously with minimum incubation time at each temperature, a quadriplex, highly sensitive PCR assay was performed. The use of four primer sets designed in different genomic regions of HCMV allowed the detection of variants and achieved maximal sensitivity and specificity which are essential for a diagnostic utilization. J. Clin. Lab. Anal. 13:99–105, 1999. © 1999 Wiley‐Liss, Inc.     

人巨细胞病毒pp65抗原血症检测方法的建立和初步临床应用

目的　建立人巨细胞病毒抗原 pp6 5 (HCMVpp6 5 )血症特异、灵敏和低成本的酶免组化和荧光免疫组化方法 ,以利于临床推广应用。方法　以HCMV AD16 9感染的人胚肺成纤维细胞 (HELF)爬片作阳性对照 ,选择试剂和材料组建试剂盒 ,并与商品化的同类试剂盒作比较 ,建立人外周血多形核白细胞 (PMNLs)中HCMVpp6 5抗原阳性细胞的检测方法 ,然后再用荧光定量PCR(FQ PCR)方法做相应考评。 结果　我们建立的HCMVpp6 5抗原血症检测法能成功地检出PMNLs中的 pp6 5阳性细胞。其可检测限分别为 10 2 pfu/ml的AD16 9攻击 2 4h后的HELF细胞爬片和 3～ 5个 pp6 5阳性细胞 / 2× 10 5PMNLs ;用高相对分子质量 (5 0 0 0 0 0 )的葡聚糖能快速、有效地分离PMNLs ;用 4 %中性多聚甲醛固定的细胞片 ,于 - 2 0°C或以下可长期保存 (≥ 6个月 ) ,而且 pp6 5抗原性稳定。 结论　自建的试剂盒与同类进口试剂盒相比 ,检测 pp6 5的结果差异无显著性 ,并与FQ PCR的检测结果相一致 ,其检测特异、灵敏、操作简单、费用低廉 ,适宜临床实验室推广应用。     

Reengineering a database for clinical trials management: lessons for system architects

This paper describes the process of enhancing Trial/DB, a database system for clinical studies management. The system's enhancements have been driven by the need to maximize the effectiveness of developer personnel in supporting numerous and diverse users, of study designers in setting up new studies, and of administrators in managing ongoing studies. Trial/DB was originally designed to work over a local area network within a single institution, and basic architectural changes were necessary to make it work over the Internet efficiently as well as securely. Further, as its use spread to diverse communities of users, changes were made to let the processes of study design and project management adapt to the working styles of the principal investigators and administrators for each study. The lessons learned in the process should prove instructive for system architects as well as managers of electronic patient record systems.     

人巨细胞病毒临床分离株对更昔洛韦耐药的表型分析

目的检测分析人巨细胞病毒（HCMV）临床分离株的更昔洛韦（GCV）耐药表型。方法收集临床接受GCV治疗过的各类移植受体的血液或尿液标本以及婴幼儿HCMV感染症患儿的尿液标本,分离HCMV。然后通过噬斑减少试验测试其对GCV药物的耐受性。病毒株对GCV的耐受性程度表示以不加药物孔中病毒致细胞病变效应（CPE）为参照,能够抑制50％CPE的药物浓度（IC50）为GCV的耐受性。GCV敏感型毒株的IC50为≤5．000μmol／L。结果以标本接种人胚肺成纤维细胞（MRC-5）,最终获得病毒株共33株。其中6株来自移植受体,27株来自婴幼儿HCMV感染症患儿。以MRC-5为敏感细胞,调整所测病毒浓度为100×50％组织培养感染量（TCID50）,并加入不同浓度的GCV药物,检测发现32株GCV的IC50均≤5．000μmol／L（1．500～5．000μmol／L）,只有1株GCVIC50为12．500μmoL／L。同步平行检测的标准毒株HCMVAD169的GCVIC50为1．500μmol／L。结论药物耐受表型测定能够了解并评估病毒对GCV药物的敏感与否,但全过程周期较长,技术要求比较高,尤其必须以获得活病毒为前提,尚难以直接推向临床实验室。     

Overview of recent clinical and methodological advances from clinical trials of cardiovascular disease

Concurrently controlled, randomized clinical trials play an important role in the validation of treatment and control measures of cardiovascular disease. As such trials have been carried to conclusion, a great deal has been learned not only about the treatment of the disease but also about the methodology of clinical trials. Seven recently completed clinical trials, the Coronary Drug Project, the Aspirin Myocardial Infarction Study, the Anturane Reinfarction Trial, the Hypertension Detection and Follow-Up Program and three drug trials of betablockers, are reviewed from the perspective of both their clinical and methodological significance.     

Tuberculosis vaccine development: research,regulatory and clinical strategies

In the past decade, while the global tuberculosis (TB) epidemic has continued to devastate mankind, considerable progress has nevertheless been made in the development of new and improved vaccines for this ancient disease. Recombinant bacillus Calmette–Guerin strains, DNA-based vaccines, live attenuated Mycobacterium tuberculosis vaccines and subunit vaccines formulated with novel adjuvants have shown promise in preclinical animal challenge models. Three of these vaccines are being evaluated at present in human clinical studies, and several other vaccine preparations are being targeted for clinical trials in the near future. Although the preclinical characterisation and testing of new TB vaccines has clearly led to exciting new findings, complex regulatory and clinical trial design issues remain as a challenge to TB vaccine development. This report reviews some of the exciting advances in TB research that have led to the development of new TB vaccines, and addresses the unique regulatory and clinical issues associated with the testing of novel anti-TB preparations in human populations.     

Dengue vaccine: priorities and progress

Dengue transmission has increased considerably in the past 20 years. Currently, it can only be reduced by mosquito control; however, the application of vector-control methods are labor intensive, require discipline and diligence, and are hard to sustain. In this context, a safe dengue vaccine that confers long-lasting protection against infection with the four dengue viruses is urgently required. This review will discuss the requirements of a dengue vaccine, problems, and advances that have been made. Finally, new targets for research will be presented.     

人巨细胞病毒感染的检测及临床表现分析

目的 探讨血清人巨细胞病毒（HCMV）-IgM和尿液HCMV-DNA检测对婴、幼儿HCMV感染临床诊断的意义.方法 选择67例确诊为HCMV感染的婴、幼儿,分别采用酶联免疫吸附测定（ELISA）、荧光定量聚合酶链反应（PCR）检测血清HCMV-IgM及尿液HCMV-DNA.结果 HCMV感染的临床表现以肺炎和肝功能异常多见.67例确诊患儿中,血清HCMV-IgM检测的阳性检出率为71.6%,尿液HCMV-DNA检测的阳性检出率为88.1%.二者联合检测,其阳性检出率为95.5%.结论 血清HCMV-IgM和尿液HCMV-DNA联合检查可提高临床诊断的准确性,有助于早期诊断.