SARS疫苗研究进展

严重急性呼吸综合征（SARS）是由SARS相关冠状病毒（SARS-CoV）引起的一种新的传染病。虽然SARS的流行已经被有效控制，但很可能因实验室样本外泄或动物宿主中由类SARS-CoV演化而来的病毒的分离株导致再次爆发，阻止SARS再次流行最有效的方法就是研制安全有效的疫苗，所以，SAILS疫苗的研究仍然是目前SARS相关研究的重点。不同类型SARS疫苗的研究已经迅速展开，并且有些疫苗研究已取得了突破性的进展，进入了临床试验阶段。但在SARS疫苗的研究过程中也遇到了很多问题，如抗体依赖性感染增强（ADE）、SAILS-CoV病毒变异快、没有理想的动物模型等。本文对SARS疫苗的研究、疫苗研究中存在的问题等进行了综述。     

SARS冠状病毒S1基因片段真核表达载体的构建及其活性测定

严重急性呼吸综合征（severe acute respiratory syndrome,SARS）病原体是SARS冠状病毒（SARSCoV）,研究开发安全有效的SARS-CoV疫苗以控制SARS成为热点.经过对12株SARS冠状病毒基因序列比较,发现S蛋白的氨基酸突变率仅为0.23%,其较高的保守性为疫苗研究奠定了良好的基础,由此,S蛋白成为候选疫苗的重要靶位.pcDNA3.1（＋）是一种高效率的质粒型真核表达载体.本研究将SARS-CoV的S1基因片段连至真核表达载体pcDNA3.1（＋）,构建重组pcDNA3.1（＋）/S1并初步研究其免疫效果.     

SARS病原体特征与临床实验室诊断

SARS的全球性流行带来了严重的公共卫生问题和社会经济问题.目前,在SARS病原体鉴定、基因组结构和序列变异、SARS流行特征和实验室诊断等方面获得了很大的进展.现已证实SARS的病原体为SARS冠状病毒.SARS冠状病毒是一种与原来已知冠状病毒在某些方面类似、但又独具特征的新型冠状病毒,该病毒的起源可能源于野生动物.多个SARS冠状病毒的全基因组核酸序列测定现已完成,在SARS冠状病毒的实验室诊断方面,现已有了免疫学方法检查抗体和分子生物学方法检查病毒RNA.直接检测病毒抗原和定量检测病毒多靶点基因是今后的发展方向.     

科学家进一步证实SARS病毒来源于中华菊头蝠

近期中国科学院武汉病毒研究所石正丽研究员带领的国际研究团队分离到一株与 SARS（Severe acute respiratory syndrome coronavirus）病毒高度同源的 SARS 样冠状病毒（SARS-like CoV），进一步证实中华菊头蝠是 SARS 病毒的源头。
　　SARS 冠状病毒是造成2002-2003年 SARS 暴发的病原，造成全球8094人感染和774人死亡的重大疫情。已有的流行病学证据和生物信息学分析显示，野生动物市场上的果子狸是 SARS 冠状病毒的直接来源。虽然在世界各地包括非洲、欧洲和中国的蝙蝠体内均发现与 SARS 病毒相似的 SARS 样冠状病毒，但这些病毒均不能利用人和果子狸的 ACE2（即人SARS 病毒受体）作为受体，不是 SARS 病毒的近亲。该团队分离的 SARS 样冠状病毒可以利用人、果子狸和中华菊头蝠ACE2作为其功能受体，并且能感染人、猪、猴以及蝙蝠的多种细胞。这些实验结果为中华菊头蝠是 SARS 冠状病毒的自然宿主提供了更为直接的证据。这些最新结果发表在2013年国际著名学术期刊 Nature。这也是该团队继2005年在Science 上发表“蝙蝠是 SARS 样冠状病毒自然宿主”之后在此领域的又一项重大突破。该项目得到国家973和基金委重大项目等资助。     

SARS-CoV基因疫苗的研究进展

SARS起病急、病程快,传染性强.目前尽管第1次全球爆发已被控制,但并不能排除其再度爆发的可能性.由于SARS的病原体已明确为一种新型的冠状病毒,人群对于SARS普遍易感,必须采取安全有效的方法防治.     

基因工程抗体分泌影响因素研究进展

基因工程抗体（gene engineering antibody，GEAb）是继多克隆血清和单克隆抗体之后的第三代抗体，在许多医学领域都极具应用潜力。众所周知，预防和治疗感染性疾病常用的药物是疫苗和抗生素，但对于如SARS、获得性免疫缺陷综合征（AIDS）等难以获得相应疫苗或疫苗治疗效果不理想的病毒感染，目前仍缺乏有效的治疗方法，     

从相关主题分析看我国严重急性呼吸综合征的研究动向

目的通过文献计量学方法分析严重急性呼吸综合征（SARS）的研究热点．发展趋势。方法利用中国生物医学文献数据（CBMdisc），通过主题词检索途径检索出2002年月11月～2005年5月间有关SARS研究文献进行文献计量学分析。结果共检出SARS丈献6829篇，文献呈下降趋势；结论治疗、预防和控制、诊断、病因学、流行病学、护理．微生物学、病毒学、心理学、并发症、免疫学等方面，是SARS研究的热点；寻找病原、研制疫苗及有效治疗，筛选有效的中药，研究中药新剂型，是SARS今后的研究方向。     

灭活SARS冠状病毒疫苗对小鼠脏器影响的实验研究

目的:探讨灭活SARS冠状病毒疫苗对小鼠是否有损伤作用。方法:用灭活SARS冠状病毒分别免疫BALB/c和C57BL/6小鼠;ELISA法检测小鼠血清中抗SARS冠状病毒抗体水平;免疫8周后取小鼠各脏器,观察其病理形态学改变。结果:免疫8 d后,小鼠血清中就可检测到特异的IgM、IgG抗体;组织切片染色观察,可见少数小鼠肺及肝组织出现轻度损伤,其他脏器未见病变。结论:SARS冠状病毒灭活疫苗可诱导小鼠产生特异性抗体,同时没有造成严重的器官损伤。这将为SARS疫苗进入临床研究打下基础。     

九种冠状病毒核衣壳蛋白的原核表达及纯化

目的 探索SARS冠状病毒（SARS-CoV）、HCoV-229E、HCoV-OC43、HCoV-NL63、HCoV-HKU1等5种人类冠状病毒以及牛冠状病毒（BCoV）、鼠肝炎病毒（MHV）、猫传染性腹膜炎病毒（FIPV）和禽传染性支气管炎病毒（IBV）4种动物冠状病毒核衣壳（N）蛋白在大肠杆菌中克隆表达及纯化条件。方法 利用原核表达载体pET30a（+）经IPTG诱导表达重组蛋白，并采用离子交换及镍离子螯合亲和层析法对重组蛋白进行纯化，用SDS-PAGE及Western blot对重组蛋白进行鉴定。结果 成功表达、纯化出9种冠状病毒N蛋白，纯度达90%以上。结论 在原核系统中表达得到了高纯度的9种冠状病毒N蛋白，为相关功能性研究奠定了基础。     

SARS-CoV核衣壳蛋白抗原性鉴定和基因免疫研究

目的　了解SARS冠状病毒 (SARS CoV)核衣壳蛋白 (N蛋白 )的抗原性及其基因疫苗的免疫原性。方法　用大肠杆菌表达SARS CoV的N蛋白 ,用SARS患者恢复期血清对其进行抗原性鉴定。再构建N蛋白基因疫苗 ,肌肉注射接种小鼠 ,检测小鼠血清中的抗N蛋白IgG抗体、脾细胞增殖和迟发型超敏反应。结果　大肠杆菌重组表达的SARS CoVN蛋白具有强抗原性 ,其基因疫苗能在小鼠有效诱导N蛋白特异性抗体和CD4 、CD8 T淋巴细胞免疫应答。结论　SARS CoV的N蛋白可作为重要的SARS血清学诊断抗原 ,并对于SARS的特异性预防和治疗有潜在的应用价值。     

Vaccine design for severe acute respiratory syndrome coronavirus

Severe acute respiratory syndrome (SARS) is an emerging infectious disease caused by a new coronavirus (SARS-CoV). Recent studies suggest that SARS-CoV is zoonotic and may have a broad host range besides humans. Although the global outbreak of SARS has been contained, there are serious concerns over its re-emergence and bioterrorism potential. As a part of preparedness, development of a safe and effective vaccine is one of the highest priorities in fighting SARS. A number of candidate vaccines, using a variety of approaches, are under development. The first vaccine tested in clinical trial is made from the inactivated form of SARS-CoV. Several live attenuated, genetically engineered or vector vaccines encoding the SARS-CoV spike (S) protein have been in pre-clinical studies. These vaccine candidates are effective in terms of eliciting protective immunity in the vaccinated animals. However, caution should be taken with the safety of whole virus or full-length S protein-based immunogens in humans because they may induce harmful immune or inflammatory responses. We propose to use the receptor-binding domain (RBD) of SARS-CoV S protein (residues 318--510) for developing a safe and effective subunit SARS vaccine, as it is not only a functional domain that mediates virus-receptor binding but also a major neutralization determinant of SARSCoV. It has been demonstrated that the RBD of SARS-CoV S protein contains multiple conformational epitopes capable of inducing highly potent neutralizing antibody responses and protective immunity.     

SARS Immunity and Vaccination

Severe acute respiratory syndrome (SARS) is a serious and fatal infectious disease caused by SARS coronavirus (SARS-Cov), a novel human coronavirus. SARS-Cov infection stimulates cytokines (e.g., IL-10,IFN-γ, IL-1, etc.) expression dramatically, and T lymphocytes and their subsets CD4^ and CD8^ T cells are decreased after onset of the disease. SARS-specific IgG antibody is generated in the second week and persists for a long time, whereas IgM is expressed transiently. The spike protein and neucleocapsid protein are most abundant in SARS-Cov and contribute dominantly to the antibody production during the course of disease.Spike protein, especially the ACE-2 binding region (318-510aa) is capable of producing neutralizing antibody to SARS-Cov. Neucleocapsid protein induces protective specific CTL to SARS-Cov. Therefore, applications with spike subunit, neucleocapsid subunit as well as inactivated SARS-Cov are three prospective vaccination strategies for SARS.     

Induction of SARS-nucleoprotein-specific immune response by use of DNA vaccine

Induction of effective cytotoxic T lymphocyte (CTL) and/or a specific antibody against conserved viral proteins may be essential to the development of a safe and effective severe acute respiratory syndrome coronavirus (SARS-Cov) vaccine. DNA vaccination represents a new strategy for induction of humoral and cellular immune response. To determine the ability of SARS-Cov nucleoprotein (N protein) to induce antiviral immunity, in this report, we established a stable C2C12 line expressing SARS-Cov N protein, which was used as a target for specific CTL assay. We also expressed recombinant N proteins in Escherichia coli and prepared N protein-specific polyclonal antibodies. C3H/He mice were immunized with N protein-expressible pcDN-fn vector by intramuscular injections. We found that the DNA vaccination induced both N protein-specific antibody and specific CTL activity to the target. When C3H/He mice were immunized by three separate injections, high antibody titre (1:3200-1:6400, average titre is 1:4580) and high CTL activity (67.4+/-8.4% (E:T = 25:1), 69.6+/-6.7% (E:T = 50:1) and 71.8+/-6.2% (E:T = 100:1)) were observed. In the case of two vaccine injections, CTL activity was also high (56.6+/-12.7% (E:T = 25:1), 57.4+/-11.7% (E:T = 50:1) and 63.0+/-6.3% (E:T = 100:1)) However, antibody titres were much lower (1:200-1:3200, average titre is 1:980). Our results suggest that SARS-Cov nucleocapsid gene might be a candidate gene for SARS DNA vaccination.     

SARS冠状病毒的病原生物学分析及其启示

Severe acute respiratory syndrome (SARS) is the first new epidemic of the twenty - first century. A novel coronavirus (SARS - CoV) has been identified as the causative agent of SAP, S. The genome of SARS - CoV has 29,727 nucleatides in length. The genome organization, with 11 open reading flames, is similar to that of conronaviruses.Phylogenetic analyses and sequence comparisons showed that SARS- CoV is not closely related to any of the known coronaviruses, indicating neither a mutant nor recombinant of well -characterized coronaviruses. It is a complete new coronavirus from nonhuman hostPathological studies show that severe immune response, associated to cytokine dysregulation, may be related to the lung damage of fatal SRAS. Recombination of genomes of wild - type strains with vaccine coronavirus is a potential risk associated with the application of living attenuated coronavirus vaccines. The proteinases, controlling the activities of the SARS- CoV replication, and spike protein, involved in viral entry and pathogenesis, represent attractive targets of anti- SARS drug development. Comparative full-length genome sequence analysis of 14 SARS coronavirus isolates suggests a remarkable genetic conservation of the virus. Anti - SARS vaccine and drug development will benefit from this genetic conservation. SARS-CoV is not likely to change rapidly and thus may not readily mutate to a benign infection. The progress in anti - SARS research has been impressive. However, one of the most effective tools in the control of the SARS is quickly tracing and isolating the contacts of stricken patients before they spread the virus further.     

Vaccines to prevent severe acute respiratory syndrome coronavirus-induced disease

An important effort has been performed after the emergence of severe acute respiratory syndrome (SARS) epidemic in 2003 to diagnose and prevent virus spreading. Several types of vaccines have been developed including inactivated viruses, subunit vaccines, virus-like particles (VLPs), DNA vaccines, heterologous expression systems, and vaccines derived from SARS-CoV genome by reverse genetics. This review describes several aspects essential to develop SARS-CoV vaccines, such as the correlates of protection, virus serotypes, vaccination side effects, and bio-safeguards that can be engineered into recombinant vaccine approaches based on the SARS-CoV genome. The production of effective and safe vaccines to prevent SARS has led to the development of promising vaccine candidates, in contrast to the design of vaccines for other coronaviruses, that in general has been less successful. After preclinical trials in animal models, efficacy and safety evaluation of the most promising vaccine candidates described has to be performed in humans.     

灭活SARS病毒的免疫原性的实验研究

研究灭活SARS病毒的免疫原性。SARS病毒F6 9株经甲醛灭活后 ,加入氢氧化铝佐剂 ,以 3种剂量接种BALB/c小鼠 ,定时采血 ,测定特异性抗体的滴度及其中和活性 ,同时用化学发光酶联免疫法测定抗血清与SARS病毒结构蛋白的反应特异性及其相对强度。结果发现 ,小鼠接种疫苗 4d后 ,血清中可检测到IgM抗体 ,直至 2 6d后逐渐下降 ;IgG抗体在初次免疫 8d后出现 ,4 7d时达最高峰 ,6 3d后进入稳定期 ;不同剂量组的抗体滴度具有明显剂效关系 ,低剂量组和中剂量组滴度峰值为 1∶192 0 0 ,高剂量组滴度峰值为 1∶384 0 0。中和实验结果表明 ,小鼠所产生的抗体具有中和病毒活性 ,在 6 3d时 ,低剂量组和中剂量组血清的中和效价为 1∶12 80 ,高剂量组血清的中和效价为 1∶5 12 0。抗体分类结果表明 ,小鼠抗血清中含有针对多种SARS病毒结构蛋白的特异性抗体 ,其中 ,针对N蛋白、S4蛋白和S2蛋白的抗体水平相对较高 ,而抗M抗体、抗 3CL抗体的水平相对较低。上述结果说明 ,SARS病毒F6 9株经甲醛灭活后 ,各主要结构蛋白仍保持较强免疫原性 ;免疫小鼠后 ,可以诱导产生高滴度的特异性混合抗体 ,在体外可以保护敏感细胞不受SARS病毒攻击     

COVID-19 vaccines: Knowing the unknown

Vaccine development against SARS-CoV-2 has drawn attention around the globe due to the exploding pandemic. Although COVID-19 is caused by a new coronavirus, SARS-CoV-2, previous research on other coronavirus vaccines, such as FIPV, SARS, and MERS, has provided valuable information for the rapid development of COVID-19 vaccine. However, important knowledge gaps remain — some are specific to SARS-CoV-2, others are fundamental to immunology and vaccinology. Here, we discuss areas that need to be addressed for COVID-19 vaccine development, and what can be learned from examples of vaccine development in the past. Since the beginning of the outbreak, the research progress on COVID-19 has been remarkable. We are therefore optimistic about the rapid development of COVID-19 vaccine.     

Exosomal vaccines containing the S protein of the SARS coronavirus induce high levels of neutralizing antibodies

Infection with the SARS-associated coronavirus (SARS-CoV) induces an atypical pulmonary disease with a high lethality rate. Although the initial SARS epidemic was contained, sporadic outbreaks of the disease still occur, suggesting a continuous need for a vaccine against this virus. We therefore explored exosome-based vaccines containing the spike S proteins of SARS-CoV. S-containing exosomes were obtained by replacing the transmembrane and cytoplasmic domains of the S protein by those of VSV-G. The immunogenicity and efficacy of the S-containing exosomes were tested in mice and compared to an adenoviral vector vaccine expressing the S protein. Both, S-containing exosomes and the adenoviral vector vaccine induced neutralizing antibody titers. After priming with the SARS-S exosomal vaccine and boosting with the adenoviral vector the neutralizing antibody titers exceeded those observed in the convalescent serum of a SARS patient. Both approaches were effective in a SARS-S-expressing tumor challenge model and thus warrant further investigation.     

A chimeric multi-epitope DNA vaccine elicited specific antibody response against severe acute respiratory syndrome-associated coronavirus which attenuated the virulence of SARS-CoV in vitro

Epitope-based vaccines designed to induce antibody responses specific for severe acute respiratory syndrome-associated coronavirus (SARS-CoV) are being developed as a means for increasing vaccine potency. In this study, we identified four B cell epitopes from the spike (S) and membrane (M) protein through bioinformatics analysis and constructed a multi-epitope DNA vaccine. Intramuscular immunization of mice with this vaccine was sufficient to induce specific prime as well as a long-term memory humoral immune response to at least two candidate epitopes, S(437-459) and M(1-20). A DNA prime-protein boost strategy greatly enhanced the antibody generation and the immune sera not only reacted with the lysates of SARS-CoV-infected Vero cells but also neutralized the cytopathic effect of SARS by 75% at 1:160 dilution. The novel immunogenic S protein peptide revealed in this study provides new target for SARS vaccine design; and our work indicated multi-epitope DNA vaccine as an effective means for eliciting polyvalent humoral immune response against SARS-CoV.     

Emerging respiratory viruses: challenges and vaccine strategies

The current threat of avian influenza to the human population, the potential for the reemergence of severe acute respiratory syndrome (SARS)-associated coronavirus, and the identification of multiple novel respiratory viruses underline the necessity for the development of therapeutic and preventive strategies to combat viral infection. Vaccine development is a key component in the prevention of widespread viral infection and in the reduction of morbidity and mortality associated with many viral infections. In this review we describe the different approaches currently being evaluated in the development of vaccines against SARS-associated coronavirus and avian influenza viruses and also highlight the many obstacles encountered in the development of these vaccines. Lessons learned from current vaccine studies, coupled with our increasing knowledge of the host and viral factors involved in viral pathogenesis, will help to increase the speed with which efficacious vaccines targeting newly emerging viral pathogens can be developed.