结核疫苗研究的历史与现状

由于结核病缺乏有效的疫苗保护，发病率持续增高，成为人类传染病中继艾滋病之后的第二大杀手。减毒牛型结核分枝杆菌——卡介苗是目前许多国家批准应用于人体的惟一结核病疫苗。然而，卡介苗对成人肺结核的保护效率很低，研制新型结核病疫苗迫在眉睫。多种类型的新型疫苗，包括重组卡介苗疫苗、营养缺陷型结核分枝杆菌疫苗、蛋白质多肽疫苗、DNA疫苗、以病毒为载体的结核分枝杆菌亚单位疫苗等被广泛研究。至2005年，已有120种以上的疫苗进行了动物实验研究，至少有5个疫苗已进入Ⅰ期临床试验。     

结核病新疫苗的研究进展和临床试验

结核病是一种在感染、免疫、预防和治疗等方面充满矛盾和挑战的慢性传染病。1882年德国科学家Koch就已分离出结核病的病原菌——结核分枝杆菌（Mycobacterium tuberculosis，结核菌）；1921年预防结核病的卡介苗（BCG）研制成功，但半个多世纪的应用结果表明，BCG预防成人肺结核无效；能有效杀死或抑制结核菌的多种抗菌药物已广泛应用了半个多世纪，但至今结核病在发展中国家的发病率和病死率一直居高不下，一些发达国家也因AIDS、移民和贫困等社会问题，导致结核病发病率回升，故结核病仍是全球感染性疾病的第一“杀手”，且结核菌的耐药性问题已越来越严峻。因此，研制安全有效的结核病新疫苗乃当务之急。     

结核分枝杆菌esat-6基因疫苗的构建和免疫原性的研究

目的　构建以结核分枝杆菌H3 7Rvesat - 6基因为基础的基因疫苗 ,并研究其免疫原性。方法　采用BamHⅠ和EcoRⅠ双酶切含有esat- 6目的基因的质粒pGEM -Teasy -esat6 ,10 g L-1琼脂糖凝胶电泳回收约 30 0bp大小片段 ,以亚克隆法构建于真核表达载体 pcDNA3 1的相应酶切位点阳性克隆经酶切鉴定证实。重组表达质粒肌注免疫BALB/c小鼠三次 ,每次间隔 2周 ,ELISA检测小鼠血清中产生抗体的水平。结果　用BamHⅠ和EcoRⅠ酶切鉴定证实目的基因正确插入载体 ,命名为pcDE6 ,重组质粒免疫小鼠体内产生特异性抗体。结论　所构建的重组真核表达质粒pcDE6能引起免疫动物的特异性体液免疫反应 ,应进一步研究其刺激机体的细胞免疫应答 ,以用于结核病 (TB)的防治研究     

应用结核病DNA疫苗治疗小鼠耐多药结核病的研究

目的 研究结核分枝杆菌Ag85A质粒DNA疫苗单独或联合药物治疗小鼠耐多药结核病的效果,为建立耐多药结核病的免疫治疗新策略和新方案奠定基础.方法 用结核分枝杆菌高耐利福平、低耐异烟肼临床分离株HB361尾静脉注射17～19 g的6～8周龄雌性BALB/C小鼠后,将小鼠随机分为6组,每组10只.感染后第2天开始,分别用pVAX1载体(A组)、利福平(B组)、吡嗪酰胺(C组)、Ag85A质粒DNA疫苗(D组)、Ag85A质粒DNA疫苗联合利福平(E组)、Ag85A质粒DNA疫苗联合吡嗪酰胺(F组)治疗60 d.治疗结束后4周,分别取肺、肝和脾观察病理改变,称取重量,做菌落计数.结果 小鼠感染4周后,肺内菌量达到1.5×107 CFU,脾内菌量达到1.1×106 CFU.A、B组小鼠死亡率均为10%,其余各组小鼠均存活.治疗结束后4周,肺组织病理显示,各治疗组肺组织病变均有不同程度减轻,病变局限,可见正常的肺泡结构,肺泡轮廓相对清晰.与A组比较,C、D、E、F组肺组织菌落数分别减少了1.18、1.35、1.38、1.08 logs,脾脏菌落数分别减少了0.91、1.00、1.26、1.03 logs(P＜0.01).结论 结核分枝杆菌Ag85A质粒DNA疫苗单独或联合药物治疗小鼠耐多药结核病均有显著疗效.Ag85A质粒DNA疫苗与抗结核药物联合治疗是治疗耐多药结核病的最有前途的免疫策略.     

结核病黏膜疫苗的研究进展北大核心CSCD

呼吸道黏膜免疫是机体抵御结核分枝杆菌(Mycobacterium tuberculosis,MTB)感染的第一道防线,是重要的抗MTB感染的保护性免疫,如何通过黏膜免疫,诱导黏膜免疫系统产生抗MTB感染的特异性免疫,是目前结核病疫苗研究的新方向。本文基于近年来结核病黏膜疫苗的研究,总结了不同类型疫苗的特点、黏膜免疫后的免疫学特性和免疫保护效果,展望了未来结核病黏膜疫苗的研究方向,希望能够对研发更加高效的结核病黏膜疫苗有所启示。     

应用结核病DNA疫苗治疗小鼠耐多药结核病的研究

Objective To establish foundation for new strategy and program on immune therapy of multi-drug resistant tuberculosis (MDR-TB) by studying the therapeutic effects of Mycobacterium tuberculosis Ag85A plasmid DNA vaccine alone or combined with drugs on MDR-TB mice. Methods Sixty 6-8 weeks old female BALB/C mice were injected via tail vein with clinical isolate Mycobacterium tuberculosis HB361 which was highly resistant to rifampin (RFP) and lowly resistant to isoniazid. The mice were randomly divided into six groups, ten mice in each group. From the second day after infection,the mice respectively received pVAX1 vector (group A), RFP (group B), pyrazinamide (PZA) (group C),Ag85A plasmid DNA vaccine (group D), Ag85A plasmid DNA vaccine combined with RFP (group E),Ag85A plasmid DNA vaccine combined with PZA (group F) for sixty days. Four weeks after the end of treatment,the lung, liver and spleen of the mice were taken and their pathological changes, weight and colony count were examined. Results Four weeks after infection, the numbers of bacteria in lung and spleen of the mice reached up to 1.5×107 CFU and 1.1 × 106 CFU,respectively. The death rates of mice in group A and group B were both 10% ,and the mice in other groups were alive. Four weeks after the end of treatment,lung pathology in the treated groups showed that the lung lesions were slight and limited,normal alveolar structure were seen, and the profile of the alveoli was relatively clear. Compared with group A, group C, D, E, F reduced by 1.18,1.35,1.38,1.08 logs on the colony count of lung, and reduced by 0.91,1.00,1.26 and 1.03 logs on the colony count of spleen (P＜0.01), respectively. Conclusions Mycobacterium tuberculosis Ag85A plasmid DNA vaccine alone or combined with drugs has significant therapeutic effects on MDR-TB mice. Ag85A plasmid DNA vaccine combined with anti-tuberculosis drugs is the most promising immunization strategy for treatment of MDR-TB.     

应用结核病DNA疫苗治疗小鼠耐多药结核病的研究

Objective To establish foundation for new strategy and program on immune therapy of multi-drug resistant tuberculosis (MDR-TB) by studying the therapeutic effects of Mycobacterium tuberculosis Ag85A plasmid DNA vaccine alone or combined with drugs on MDR-TB mice. Methods Sixty 6-8 weeks old female BALB/C mice were injected via tail vein with clinical isolate Mycobacterium tuberculosis HB361 which was highly resistant to rifampin (RFP) and lowly resistant to isoniazid. The mice were randomly divided into six groups, ten mice in each group. From the second day after infection,the mice respectively received pVAX1 vector (group A), RFP (group B), pyrazinamide (PZA) (group C),Ag85A plasmid DNA vaccine (group D), Ag85A plasmid DNA vaccine combined with RFP (group E),Ag85A plasmid DNA vaccine combined with PZA (group F) for sixty days. Four weeks after the end of treatment,the lung, liver and spleen of the mice were taken and their pathological changes, weight and colony count were examined. Results Four weeks after infection, the numbers of bacteria in lung and spleen of the mice reached up to 1.5×107 CFU and 1.1 × 106 CFU,respectively. The death rates of mice in group A and group B were both 10% ,and the mice in other groups were alive. Four weeks after the end of treatment,lung pathology in the treated groups showed that the lung lesions were slight and limited,normal alveolar structure were seen, and the profile of the alveoli was relatively clear. Compared with group A, group C, D, E, F reduced by 1.18,1.35,1.38,1.08 logs on the colony count of lung, and reduced by 0.91,1.00,1.26 and 1.03 logs on the colony count of spleen (P＜0.01), respectively. Conclusions Mycobacterium tuberculosis Ag85A plasmid DNA vaccine alone or combined with drugs has significant therapeutic effects on MDR-TB mice. Ag85A plasmid DNA vaccine combined with anti-tuberculosis drugs is the most promising immunization strategy for treatment of MDR-TB.     

结核病疫苗的抗结核免疫机制的研究进展

结核病是由结核分枝杆菌(Mycobacterium Tuberculosis,MTB)所引起的一种慢性传染病,严重危害人类健康,是目前全球范围内,尤以发展中国家为首,是受危害最为严重的慢性传染病之一。目前,预防结核病最常见且有效的疫苗是卡介苗(Bacillus Calmette-Guérin,BCG),但由于其对成人肺部结核保护作用的不确定性,再加上外界因素的改变也使卡介苗难以满足人类预防结核病的迫切需求,因此,新型抗结核疫苗的研发显得格外紧迫和重要。本文将介绍减毒活疫苗VPM1002疫苗,蛋白质/佐剂疫苗H4/H56:IC31疫苗,病毒载体疫苗腺病毒载体疫苗和其他已经进入临床试验的疫苗,以及一些尚在研究的抗结核免疫机制的研究现状,为以后的结核病防治提供参考。     

牛结核病DNA疫苗研究现状

牛结核病是一种严重的人畜共患病,其流行严重地影响畜牧业的发展,不仅造成奶牛乳房炎、结核性胸膜炎等疾病,造成奶牛产乳率和乳质下降,还严重威胁着人类的健康。据统计,人结核病有10％以上是由牛分枝杆菌引起,因此控制牛结核病具有重大的公共卫生学意义。自疫苗问世以来,其在传染病的预防控制中发挥了重要的作用,但迄今还没有一种疫苗可用于牛结核病的预防。     

结核病重组蛋白亚单位疫苗研究进展

卡介苗是唯一应用于临床的结核病疫苗,但是其对成人结核病的保护效果仍存在不确定性。重组蛋白亚单位疫苗可提供长期的免疫保护效果,且成分明确、安全性好,因而具有较好的应用开发前景。作者对结核病重组蛋白亚单位疫苗的组分(结核分枝杆菌保护性抗原和免疫佐剂)、临床研究现况、应用策略及研究所面临的挑战等方面的进展进行了综述。     

无导线心脏起搏器的现状与展望

50年来,随着新装置的增多和患者寿命的延长,电极导线并发症的发生率也在增加,如感染、脱位和断裂,拔除导线是一项高风险的操作[1-2].心脏再同步治疗(CRT)临床获益的同时,约30％患者对CRT不反应,原因之一是左心室电极导线位置不佳[3-4],并有一定的失败率和并发症[5].研究表明左心室心内膜起搏较心外膜起搏能减少电传导延迟,因此有更多获益[ 6].基于上述原因,无导线心脏起搏应运而生.     

DNA vaccine therapy for Alzheimer's disease: present status and future direction

Alzheimer's disease is the most common cause of dementia characterized by progressive neurodegeneration. Based on the amyloid cascade hypothesis, a vaccine therapy for Alzheimer's disease (AD) was developed as a curative treatment. In 1999, the amyloid beta (Abeta) reduction in AD model transgenic mice with active vaccination with Abeta peptide was first reported. Although the clinical trials of active vaccination for AD patients were halted due to the development of meningoencephalitis in some patients, from the analysis of the clinical and pathological findings of treated patients, the vaccine therapy is thought to be effective. Based on such information, the vaccines for clinical application of human AD have been improved to control excessive immune reaction. Recently, we have developed non-viral DNA vaccines and obtained substantial Abeta reduction in transgenic mice without side effects. DNA vaccines have many advantages over conventional active or passive immunization. In this article, we review conventional vaccine therapies and further explain our non-viral DNA vaccine therapy. Finally, we show some data regarding the mechanisms of Abeta reduction after administration of DNA vaccines. DNA vaccination may open up new avenues of vaccine therapy for AD.     

The present status of rotavirus vaccine development

Rotavirus infection is one of the most important causes of morbidity in young children throughout the world. The high associated mortality in Southeast Asia (and elsewhere) warrants the development of a vaccine. It is probable that most of the life-threatening watery diarrhoea due to rotavirus infection occurs as a result of primary infection in children aged 6-18 months after protection due to maternal antibody has diminished. Thus rotavirus vaccines are targeted at young infants from birth to 3 months of age. At present three candidate rotavirus vaccines (RIT-4237, MMU-18007, WC3) have undergone trials in young children. A bovine rotavirus strain (RIT-4237), was shown to be safe, immunogenic and efficacious in prevention of severe rotavirus diarrhoea in young children in Finland. However it was found to be weakly immunogenic in infants in developing countries, and to have only low efficacy in prevention of disease. A simian rotavirus strain (RRV, MMU-18006) has proved to be highly immunogenic and its reactinogenicity to be diminished by pre-existing maternal antibody (in infants aged 1-4 months). It has high efficacy against clinically severe rotavirus infection. However protection is homotypic against human serotype 3 only so that eventually a multivalent vaccine incorporating reassortant rotavirus strains that protect against human serotypes 1, 2, 4 (and other newer serotypes) may be required. It is hoped that, once safe immunogenic and protective candidate rotavirus vaccines are identified, they can be administered in an acceptable form with no alteration to existing immunization schedules.     

Diagnosis of tuberculosis: present and future

Current methods used worldwide for diagnosis of tuberculosis (TB) are not markedly different from those used 50 years ago. The standard has been to demonstrate microbiologically the presence of Mycobacterium tuberculosis in secretions and/or tissue from the patient. Improvements have been made that permit greater sensitivity for the examination of stained smears and for more rapid detection of growth of the organism using radiometric techniques. New methods for diagnosis that may well eliminate the need for smear and culture of specimens are under varying stages of development. These new methods are based on the detection of specific components of the organisms or on detection of specific antibodies produced by the patient. Some of these methods will require expensive and sophisticated equipment, and this will make them much less available in developing countries. The use of gene probes for diagnosis of TB is in use now on a limited scale. For the near future, we predict that nucleic acid techniques will be developed for use worldwide. These techniques will have a sensitivity and specificity never before achieved; they should be less expensive than standard methods, and the time required for analysis of a sample and the reporting of results will be reduced to 1 day.     

The chemotherapy of tuberculosis: past, present and future

The history of the development of modern chemotherapy for tuberculosis (TB), largely due to the British Medical Research Council, is first described. There is a current need to shorten the duration of treatment and to prevent and cure drug-resistant disease. These aims will only be achieved if the way in which multidrug treatment prevents resistance from emerging and the reasons for the very slow response to chemotherapy are understood. Consideration of mutation rates to resistance and the size of bacterial populations in lesions makes it very unlikely that resistance would emerge spontaneously, leaving irregularity in drug taking and inadequate dosage as the main reasons for its occurrence. Slow response to treatment seems due to the presence of persister populations whose natural history is only partly known. In the future, we need to explore the persister state in patients and in experimental murine TB, and to take it into account in the design of future mouse experiments. The activity of rifamycins and pyrazinamide is being increased by a rise in rifamycin dosage and the inhalation of pyrazinoic acid. New drugs are gradually being brought into use, initially TMC207 and the nitroimadazoles, PA824 and OPC67683. They will need to be tested in new combination regimens for drug-susceptible and multi- and extensively drug-resistant disease.     

Current status and future prospects for new therapies for pulmonary tuberculosis

PURPOSE OF REVIEW: Nowadays tuberculosis is becoming a worldwide problem, and according to the World Health Organization, which declared tuberculosis a global health emergency in 1993, each year 8 million people worldwide develop the active disease and almost 3 million die. RECENT FINDINGS: Due to this problem there is an urgent need for new strategies and drugs to fight against this disease. In this context, this review describes promising new classes of compounds against tuberculosis that are under study, as well as promising drugs that may soon be introduced onto the market. Another subject reported in this review is inhaled therapy, an important route under study for delivering antitubercular drugs directly to the lungs. SUMMARY: The implications of new drugs and inhaled therapy in tuberculosis treatment are fewer toxic side-effects, improved pharmacokinetics properties, extensive and potent activity against Gram-positive and Gram-negative bacteria, including resistant strains, and a reduction in the total treatment time.