Evaluation of the Protection against Infectious Bursal Disease (IBD) Challenge in Progeny Born to Parents Having Received a Vaccination Program Using a Herpesvirus of Turkey-Infectious Bursal Disease (HVT-IBD) Vector Vaccine

Broiler breeder vaccination against IBD is usually based on the injection of at least one inactivated vaccine in oil adjuvant, typically included in a combined vaccine. Priming using one or several IBD vaccine (s) has been the most common way to immunize the breeders so far. In summary, protection against vvIBD challenge in chicks of one commercial genetic line vaccinated in ovo with the HVT-IBD vector vaccine was demonstrated. The parents’ IBD vaccination program, using the HVT-IBD vector vaccine alone, the HVT-IBD vector vaccine plus IBD inactivated vaccine, and inactivated IBD vaccine alone, did not impair their progeny’s in ovo HVT-IBD vector vaccine take and subsequent protection against vvIBD virus challenge. An advantage in terms of immunization of the progeny against vvIBD was shown in the chicks born to breeders vaccinated with the HVT-IBD vaccine as a primer, as compared to breeders vaccinated with the inactivated vaccine alone. High level of IBD maternally-derived antibodies transmitted to the progeny by their parents induces together with an early onset of immunity by in ovo injection of a HVT-IBD vector vaccine clinical protection, as monitored on bursas, after vvIBD virus challenge.

The Perspective of Acquired Immunity to Combat against Infectious Diseases: An Overview

There is a long ritual of acquired immunity using physical exercise, a balanced diet, and pharmaceutical medication to generate immunity against a particular disease insight into the human body. This paper has extensively reviewed the impact of exercise, daily life practice, food selection, and several other issues to improve the immune system that combat infection. Studying the effect of exercise in varying degrees on the immunity system of humans is well developed and exhibit in this study. It investigates the prevention of pandemics due to herd immunity and finds the perfect amount of exercise to boost immunity to its maximum. Besides the life practice, it is also explored that vaccination can improve and optimize herd immunity.

China-invented vaccines against vacdnepreventable diseases for Belt&Road countries

Vaccine is a principal and highly cost-effective medical method on controlling infectious diseases and improving population health.Various vaccines are eagerly needed in the low-income countries along the Belt&Road.With the good quality to reach WHO prequalification standard,and the abundant capacity to fulfill the demand from market abroad,upon the platform of China-proposed"the Belt&Road Initiative",the vaccines manufactured in China are exporting to countries worldwide.The independent innovative vaccines'R&D system,which fruited a series of innovative infectious diseases vaccines(EV71 vaccine,sIPV,HEV,Ebola vaccine,etc.)to be launched in Chinese market,indicates that China has developed rapidly from"a great vaccine-production country"to"a powerful vaccine-innovation country".The implementation of National Innovation-driven Development Strategy would further push forward the developm ent and internationalization process of Chinese innovative vaccines.Therefore,the China-invented vaccines will make an important role in the prevention and control of infectious disease in various countries and become one of the most powerful weapons in fighting the global epidemic event in the future.

Preparation and Examination of Inactivated Emulsion Vaccine against Newcastle Disease, Infectious Bronchitis and H9 Subtype Avian Influenza

[ Objective] To prepare inactivated emulsion vaccine against Newcastle disease, infectious bronchitis and H9 subtype avian influenza. [ Method] Antigen fluid of Newcastle disease virus （NDV） La Sota strain, infectious bronchitis virus （IBV） M41 strain and HgN2 subtype avian in- fluenza virus （AIV） WD strain was prepared by propagation in chicken embryos, respectively. The antigen fluid was concentrated with FILTRON Cassette ultra-filtration system and inactivated by formalin. The antigen fluid of NDV, IBV and AIV was mixed at a volume ratio of 1：1：1. Then the mixture was emulsified by Span-80 and Tween-80 and added medical white oil as adjuvant. The sterility and physical characteristics of the prepared ND-IB-AI combined vaccine were detected. [ Result] The three batches of ND-IB-AI combined vaccine were germ-free, milky white, with water-in- oil pattern and with viscosity of 6.3 -6.8 s. The water and oil were not separated after rest at 37 ~C for 21 d or centrifugation. [ Conclusion] The three batches of ND-IB-AI combined vaccine were germ-free and reached the standard for physical characteristics of vaccines.

Effect of Chicken Akirin2 Gene on Immune Response Induced by VP2 DNA Vaccine of Infectious Bursal Dis-ease Virus

[ Abstracts ] In order to investigate the effect of chicken Akirin2 gene on the immune response induced by VP2 DNA vaccine of infectious bursal disease virus （IBDV）. [ Methods] The 14-day-old SPF chickens were immunized with recombinant plasmids expressing VP2 protein and Akirin2 protein, and strength- ened immunization was conducted at the 14＇~ day after the first immunization. Finally, test chickens were challenged with IBDVBC6-85 virulent strain. [ Resultss ] Test results showed that Akirin2 gene could enhance the specific immune response induced by VP2 DNA vaccine, improve the proliferation of peripheral blood lym- phocytes and ＇affect the expressing of cytokines TNF-a, IFN-Y, IL-1β, IL-2, IL-4, IL 6, IL-9, IL-10, IL-17 and IL-18. Effects of recombinant plasmids co-ex- pressing Akirin2 protein and VP2 protein on cytokine expression showed some differences with the recombinant plasmids expressing Akirir/2 protein or VP2 protein along. [ Conclusions] Chicken Akirin2 gene could significantly enhance the humoral immune response and cellular immune response induced by VP2 DNA vaccine of IBDV.

Titration Method Validation of Live Vaccines against Infectious Bursal Disease

Validating a method of analysis goes through different steps, which aims at testing the normality of measurements distribution, estimating the uncertainty of the components of a measurement （i.e., accuracy and correctness）, and finally, define the control tests of non degradation of the method performances. This paper outlines the steps for validating a biological method of analysis. It involves the construction of an experimental design, a statistical model, and the preparation of an interne laboratory reference material （pilot vaccine）. The latter is used to study the impact of deviation and variation factors, in order to, optimize the analytical method, to evaluate the bias （random error）, and to calculate the uncertainty of measurement, and make the control charts. This method is applied in the titration of live viral vaccines of Gumboro disease on chicken＇s embryos fibroblasts. The experimental results show that potential influence factors related to the titration method had no significant influence on the obtained results. Taking into account these results, an operating mode has been elaborated. The finalized method proved to be faithful to standard deviation of repeatability and reproducibility of 0.21 and 0.22, respectively, with a confidence level of 95%. The calculated uncertainty of measurement is equal to 0.2, which represents the average error level of a titer. A homogeneous stock of interne laboratory reference vaccine （MRIL）, with an average titer of 5.9 log DIT 50, was produced and the control chart set in away to provide the laboratory with an important tool of control and monitoring of the viral titers evolution in time, as well as, the mastery of the validated titration method performances.

重大传染病疫情下基于服务水平的疫苗分配及储备研究

为缓解重大传染病疫情下疫苗的短缺现状,本文结合传染病模型(susceptible-infected-recovered-deceased,SIRD)考虑疫苗需求与疫区医院收治容量的关系,以期望短缺数最小为目标建立疫苗分配模型,推导分析了最佳服务水平和储备量,并给出了不同情形下疫苗的最优分配方案。此外,通过数值模拟,进一步探究了紧急调配成本、资金预算、需求变化、疫区数量以及疫区间相关性等外生变量带来的影响,验证了模型推导结果,为疫苗分配和储备策略提供了科学依据。研究发现:疫苗接种有助于促进病毒感染曲线平坦化和降低疫情峰值,从而减轻医疗系统超负荷运转的现象,降低因感染而死亡的人数;在不考虑储备疫苗的情况下,无论需求的不确定性程度如何,为每个地区提供同等的服务水平有利于最小化疫苗期望短缺量;考虑储备疫苗的情况下,向需求波动幅度较大的疫区提供更高的服务水平可以减少期望短缺,但疫区数量较多时,为每个疫区提供同等服务水平更具公平性,即使会导致疫苗的次优覆盖;是否考虑储备疫苗取决于紧急调配成本、预算的高低以及疫区需求情况等。

T细胞免疫反应载体疫苗在人类疾病预防和治疗中的应用

人类疾病,特别是传染病和癌症,对公共卫生安全和全球经济构成前所未有的挑战。预防和治疗性疫苗的开发是应对人类疾病的优先对策。本文综述了疫苗载体的免疫学原理、T细胞载体疫苗设计策略及疫苗研究进展,为新型疫苗的设计提供新的思路。T细胞可以在机体发生感染后分化成不同的效应T细胞群,它们可以起到清除病原体的作用,关于效应T细胞功能和机制的研究对于设计能够引发基于T细胞免疫的疫苗至关重要。目前很多病毒(例如HIV、HCMV感染)和肿瘤疫苗的研发都侧重于T细胞类疫苗,在所有疫苗种类中,激活T细胞免疫反应的载体疫苗具有显著优势。许多来源的载体,包括病毒载体、细菌载体和核酸载体,它们在抗原提呈能力、免疫原性和保护效力方面都有良好的表现。此外,还总结了T细胞载体疫苗设计的策略,包括确定适当的抗原提呈途径和载体递送途径、确保生物安全性、如何选择合适的疫苗的载体、各种载体疫苗的优缺点等,尤其是mRNA疫苗在应对新冠疫情中发挥了重要的作用。疫苗载体的技术进步将会加速新型疫苗的研发,并且能促进人们对突发公共卫生事件的应对。

雾化疫苗研究进展

近年来,随着黏膜疫苗及免疫技术的不断发展,针对呼吸道疾病免疫预防的雾化疫苗及相应雾化吸入免疫技术的报道与应用逐渐增多。雾化疫苗是通过雾化装置将液态和固态免疫原制成雾滴或气溶胶颗粒,以喷雾免疫或气溶胶免疫的形式进入人与动物呼吸道及肺部,并诱导机体产生保护性应答的疫苗。雾化免疫能更好地诱导黏膜免疫应答,同时避免了注射带来的疾病传播风险和疼痛。20世纪50年代鸡新城疫疫苗的喷雾免疫研究拉开了动物呼吸道免疫的序幕,随后开展了鸡传染性支气管炎疫苗的喷雾接种,目前很多禽用疫苗的喷雾免疫已被广泛使用。猪用疫苗的气溶胶免疫研究起步较晚,难度也更大。20世纪70年代末以来,逐步在猪瘟疫苗、猪胸膜肺炎放线杆菌疫苗及猪支原体肺炎疫苗上开展相应的气溶胶免疫研究。相比动物疫苗,人用疫苗的气溶胶免疫研究报道更多,主要集中在麻疹疫苗、结核疫苗和流感疫苗。2019年以来,新型冠状病毒肺炎疫苗的气溶胶免疫快速发展,目前在中国已被批准紧急使用。笔者就动物用及人用雾化疫苗研究现状进行系统陈述,总结分析了各类雾化疫苗的理化参数、安全性、体内趋向性、肺脏局部免疫应答、免疫接种效果,并提出未来在疫苗剂型与组份、雾化发生装置、雾化过程质控、免疫程序与效果评价等方面的研究需求。本综述可为后续相应的呼吸道黏膜疫苗研发提供参考。

预防传染病mRNA疫苗原材料、原液质控要点分析

目的:梳理归纳预防传染病mRNA疫苗原材料和原液质控要点,为我国此类产品质量控制提供参考。方法:通过梳理世界卫生组织及相关标准和审评机构关于预防传染病mRNA疫苗原材料、原液质控指导文件,以及相关监管指南和文献,总结归纳预防传染病mRNA疫苗原材料和原液关键质量控制属性及相关要求。结果与结论:作为新型生物制品,mRNA疫苗核酸结构和脂质体包裹制剂的特性决定了该类疫苗质控特点,序列和完整性、含量及纯度、加帽率和包封率是mRNA疫苗特有的、决定有效性和安全性的关键质量参数。从原材料和原液制备阶段就建立多个与mRNA特性相关的质控要点及其检测方法,将有助于保障预防传染病mRNA疫苗安全有效、质量可控。

表达鸡传染性喉气管炎病毒gD蛋白的重组嵌合型新城疫病毒La Sota株的构建

为构建表达鸡传染性喉气管炎病毒(ILTV)糖蛋白D(gD)的重组新城疫病毒(NDV)La Sota株,本研究将ILTV强毒株gD基因胞外域与NDV F基因信号肽、跨膜域和胞质尾区融合,并插入到含有NDV基因VII型F和HN基因的嵌合型La Sota株感染性cDNA克隆pLa Sota-VIIF/HN的P和M基因之间,将获得的重组感染性克隆pLa Sota-VIIF/HN-gD与辅助质粒pCIneo-NP-P-L共转染BHK-21细胞,拯救出表达gD蛋白的重组嵌合型NDV La Sota株rLaSota-VIIF/HN-gD,并采用血凝试验鉴定正确后,将重组病毒在9日龄SPF鸡胚中连续传至10代,提取10代重组病毒基因组RNA,反转录成c DNA作为模板,以ILTV gD基因插入位点两侧的鉴定引物进行PCR鉴定;采用第10代重组病毒感染BHK-21细胞,以ILTV gD蛋白多克隆抗体作为一抗进行间接免疫荧光试验(IFA);分别对鸡红细胞吸附的重组病毒感染的鸡胚尿囊液上清和从红细胞上解离下来的纯化的重组NDV病毒粒子经western blot鉴定,并对重组病毒对鸡胚的致病性和在鸡胚中的复制动态进行初步研究。PCR结果显示ILTV gD基因能够在重组病毒中稳定存在;IFA和western blot鉴定结果显示,重组病毒能够正确表达ILTV的gD蛋白,而且gD蛋白嵌合表达在重组病毒颗粒上。鸡胚致病性试验和鸡胚中的复制动态试验结果显示,重组病毒保持了La Sota疫苗株的低致病性和良好的复制特性,rLaSota-VIIF/HN-gD的鸡胚平均死亡时间(MDT)为168 h,1日龄雏鸡脑内接种该重组病毒的致病指数(ICPI)为0.20,鸡胚半数感染量(EID_(50))峰值可达10^(-8.66)/100μL。本研究所制备的重组病毒r LaSota-VIIF/HN-gD为研制基因VII型NDV和ILTV的二联活疫苗奠定了基础。

兽用mRNA疫苗的研究进展

疫苗接种是动物日常保健中必不可少的。近年来,随着免疫学研究的持续发展和分子生物学技术的不断完善,mRNA疫苗在动物传染性疾病防治方面取得了一定的成果,广受各方关注。为加深对mRNA疫苗的了解,本文将从mRNA疫苗主要类型、结构特征、免疫机制、独特优势及其在兽用领域的研究现状等几个方面,对兽用mRNA疫苗目前的主要研究进展作一系统性综述,以期为后续开展mRNA疫苗相关的研究提供参考资料。

病毒载体疫苗研究进展

近十年来,中东呼吸综合征、埃博拉出血热、寨卡病毒感染、新型冠状病毒肺炎等重大传染性疾病疫情相继出现,对疫苗的快速研发提出重大挑战。其中病毒载体疫苗是新型疫苗研发的重要形式,它可以通过雾化吸入或口服等方式进行无创免疫,在没有佐剂的情况下发挥免疫作用,同时诱导体液、细胞和黏膜免疫反应,具有良好的免疫原性和安全性。随着对病毒基因组和结构蛋白等元件认识的不断深入,利用合成生物学研究思路系统设计、改造病毒载体,从而赋予重组病毒载体疫苗高滴度生产、高安全性和高免疫原性等生物学特征,对疫苗研发具有重要指导意义。本文综述了复制型、非复制型等病毒载体疫苗研发策略,以及具有临床应用价值的疫苗病毒载体,如腺病毒载体、痘病毒载体、水疱性口炎病毒载体等,希望对利用合成生物学进行新型病毒载体疫苗的研发提供一定的参考。未来,病毒载体疫苗必将向着更高的安全性、更强的保护性、更好的依从性、更低的生产成本等方向迭代发展。

长学制传染病教学中TBL(Team-Based Learning)模式的应用和改进

目的:研究TBL教学在八年制学生传染病教学中的应用成效及存在的问题,为改进和推广该教学方法提供参考依据。方法:对2006级八年制学生部分理论课采用TBL教学,进行闭卷考试及问卷调查。结论:与传统教学模式相比,TBL教学对提高学生学习兴趣,培养学分分析问题、解决问题、沟通能力和团队协作精神以及提高考试成绩均有帮助。

mRNA疫苗结构设计和疾病防治应用进展

随着生物科学技术和制药工艺的进步,mRNA疫苗在抗击癌症和感染性疾病方面显示了巨大潜力。与传统疫苗相比,mRNA疫苗具有设计简单、生产速度快、安全性好、疗效高等优势,但也存在自身稳定性差、易被体内的核酸酶降解等难题。在新冠疫情背景下,mRNA疫苗进入了快速发展阶段,有效载体的开发、mRNA免疫原性的控制、工艺成本降低和体内运输稳定性及效率的提高等改进措施,使得mRNA疫苗的临床应用进入了一个崭新的阶段。本文将对mRNA疫苗的结构设计和疾病防治应用方面取得的进展进行综述。

HPV感染的慢病管理

目前HPV的感染在全球人群中普遍存在,并且HPV感染人体后很难被彻底清除,因此由HPV感染所诱发的多种慢性疾病如病毒疣、宫颈上皮内瘤变、呼吸道乳头状瘤等往往存在着很高的复发率,给患者乃至社会均带来了沉重负担。因此,需要对HPV感染所诱发的慢性疾病进行科学规范的管理,进而降低HPV感染率与疾病复发率、缩短病程,从而有效促进HPV的防治工作。本文就HPV感染的慢病管理的必要性、具体方法及其意义进行综述。

“国际公共卫生紧急事件”下的mRNA疫苗研发

“国际公共卫生紧急事件”(简称PHEIC)是指疾病的国际传播对其他国家构成公共卫生风险,需要采取协调一致的国际应对措施的不同寻常事件。迄今为止,世界卫生组织(WHO)一共宣布了7次PHEIC,包括甲型H1N1流感、埃博拉、脊髓灰质炎、寨卡、新型冠状病毒感染和猴痘疫情。疫苗是应对传染病疫情的有力武器,合成生物学的发展突破了传统疫苗存在的难点问题和技术瓶颈,为病毒性传染病防控提供了全新的思路,尤其是mRNA疫苗作为下一代疫苗研发的平台技术,具有安全性强、有效性良好、研发周期短、易规模化生产、易扩大产能等特点,在应对新突发传染病疫情方面具有明显的优势。目前,新冠mRNA疫苗已正式获批上市,针对流感、寨卡和猴痘病毒的多款mRNA疫苗已进入临床研究阶段,埃博拉mRNA疫苗处于临床前研究阶段,而针对脊髓灰质炎病毒尚无mRNA疫苗研究的报道。本文就历次PHEIC应对中mRNA疫苗的研发进展进行了详细梳理和评述,同时对mRNA疫苗应对PHEIC的未来发展趋势和挑战进行了展望和讨论。结合合成生物学、生物化学和人工智能等多学科技术对mRNA分子设计、高效递送以及疫苗生产和储存运输等进行优化,有望进一步提高mRNA疫苗的有效性和可及性。综上,尽管尚无法预知下一次PHEIC何时会出现,但当下一次PHEIC出现时,mRNA疫苗技术一定会成为人类防范PHEIC的有力武器。

2022年邵阳市免疫规划人力资源现况调查

目的了解邵阳市免疫规划人力资源配置现状,为相关部门科学制定免疫规划人力资源配置策略提供参考依据。方法于2023年2月对邵阳市13个疾病预防控制中心、216个乡镇(街道)预防接种单位从事免疫规划人员的相关情况进行横断面调查并进行描述性分析。结果2022年邵阳市从事免疫规划工作人员共772名,其中市疾控9名、县市区疾控52名、乡镇(街道)预防接种单位711名;县市区疾控机构、乡镇预防接种单位免疫规划人员每万人分别配置0.08名、1.10名;≤7岁儿童每万人分别配置1.11名、15.24名;每km2分别配置2.50名、34.14名;县市区疾控机构免疫规划人员以年龄>29~39岁、女性、<5年免疫规划工作、在编、中级职称、本科、预防医学为主,分别为36.54%、55.77%、34.62%、86.54%、51.92%、55.77%、38.46%;乡镇(街道)预防接种单位以年龄>29~39岁、女性、<5年免疫规划工作、在编、初级职称、大专、护理学为主,分别为34.60%、83.54%、50.63%、72.15%、60.90%、46.69%、60.06%。结论邵阳市免疫规划人力资源配置低且区域间不均衡、人员流动性大,需要进一步合理配置及完善相关服务能力。

Immune Effect of Combination of Universal Molecular Adjuvant and IBDV Subunit

In order to evaluate the immune effect of the protein expressed by the universal vector pET-mLTA-CTLA-4 plus IBDV subunit, the fusion protein mLTA-CTLA-4 was expressed and purified. Protein toxicity tests were carried out on rabbits.The VP2 gene of infectious bursal virus was amplified by RT-PCR, and lately used for pET-VP2 construction. Ten-day-old free healthy chickens were chosen for a grouped test, including the mLTA-CTLA-4（at different doses） plus VP2 groups, IBDV living vaccine group and control group. Serum and mucosal samples were collected regularly and the neutralization titers of IgG and IgA were assayed, while an animal protection test was conducted to determine the protection rate. The results showed that the protein m LTA-CTLA-4 was non-toxic and its protection rate was100%. IgG or IgA levels in the IBDV vaccine group were slightly higher than those in recombinant protein groups. These results indicated that the recombinant protein mLTA-CTLA-4 could be applied with IBDV subunit vaccine to protect chickens from infection.

mRNA疫苗在动物传染病中的研究进展及应用

与传统疫苗相比,mRNA疫苗具有安全性高、有效性好、研发周期短等特点,使其在传染病的预防和控制方面具有得天独厚的优势。目前,mRNA疫苗在新型冠状病毒(COVID-19)肺炎、流感、埃博拉病毒病、寨卡病毒病等人类疾病的防控中取得了巨大进展,但动物用mRNA疫苗研究尚不深入。因此,开发动物用mRNA疫苗来预防和控制家畜、家禽、野生动物等的传染性疾病,成为动物疫病和公共卫生领域的重要研究方向之一。全面探讨了动物传染病mRNA疫苗的设计、制备、递送系统、应用、优势、挑战以及前景,为研制和开发动物传染病mRNA疫苗提供参考。