Polyfunctional T Cell and Neutralizing Antibody Responses to ACAM2000TM Smallpox Vaccine Immunization in Primary-Vaccinated Individuals

Smallpox eradication was successful via prophylactic administration of live attenuated vaccinia virus. As a result of the discontinuation of the smallpox immunization program, many individuals are now susceptible to smallpox virus infection should it be used as a biological weapon. Presently, only individuals at high risk for exposure are required to receive smallpox vaccine, such as laboratory personnel that handle variola/vaccinia virus. This study endeavored to investigate a one-year period of vaccinia virus-specific T cell responses using polychromatic flow cytometry and neutralizing (Nt) antibody responses using plaque reduction neutralization test (PRNT) in individuals receiving primary immunization (n = 5) with ACAM2000TM smallpox vaccine. Functional and phenotypic profiles of vaccinia virus-specific T cell responses were characterized. Each single functional measurement {CD107a/b expression, production of interferon g (IFN-g), macrophage inflammatory protein 1b (MIP-1b), interleukin 2 (IL-2), and tumor necrosis factor a (TNF-a)} demonstrated that vaccinia virus-specific CD8+ T cells were functional at least one time point after vaccination (p ≤ 0.05). However, vaccinia virus-specific CD4+ T cells were functional only for MIP-1b production (p ≤ 0.05). Vaccinia virus-specific CD8+ T cells induced in these individuals showed increased polyfunctionality in at least 2 phenotypes relative to pre-vaccination (p ≤ 0.05). Although only three of five individuals (60%) showed positive Nt antibody (titer ≥ 20) at first month after vaccination, all five individuals (100%) demonstrated Nt antibody at 2 months, post-immunization. Interestingly, all vaccinees could retain the Nt antibody for 6 months after primary vaccination. In conclusion, ACAM2000TM smallpox vaccine induced both polyfunctional T cell-and Nt antibody-responses in primary immunized individuals.

Insights into induction of the immune response by the hepatitis B vaccine

After more than four decades of hepatitis B virus(HBV)vaccine implementation,its safety and efficacy in preventing HBV infection have been proven and several milestones have been achieved.Most countries have included HBV immunization schedules in their health policies and progress has been made regarding universalization of the first HBV vaccine dose at birth.All of these actions have significantly contributed to reducing both the incidence of HBV infection and its related complications.However,there are still many drawbacks to overcome.The main concerns are the deficient coverage rate of the dose at birth and the large adult population that has not been reached timely by universal immunization.Additionally,the current most widely used second-generation vaccines do not induce protective immunity in 5%to 10%of the population,particularly in people over 40-years-old,obese(body mass index>25 kg/m2),heavy smokers,and patients undergoing dialysis or infection with human immunodeficiency virus.Recently developed and approved novel vaccine formulations using more potent adjuvants or multiple antigens have shown better performance,particularly in difficult settings.These advances re-launch the expectations of achieving the World Health Organization’s objective of completing hepatitis control by 2030.

不同猪繁殖与呼吸综合征疫苗组合体液免疫效果评估

为了比较不同猪繁殖与呼吸综合征(PRRS)疫苗不同免疫程序对体液免疫效果的影响,本试验选择新引进猪繁殖与呼吸综合征病毒(PRRSV)抗原和抗体均为阴性后备母猪的3个猪场,将各场内猪只按体重分为3个阶段:7~20、20~35和35~50 kg,各场分别从中选取20头猪,共180头猪。每场选用1种免疫方案,第1组混合疫苗组,为首次免疫PRRS弱毒疫苗(CH-1R株),28 d后加强免疫PRRS灭活疫苗(CH-1a株);第2组弱毒疫苗组,为2次均免疫PRRS弱毒疫苗;第3组灭活疫苗组,为2次均免疫PRRS灭活疫苗。疫苗首次免疫后14、28、42和56 d采集猪血清,进行特异性PRRSV ELISA(N蛋白)检测和中和抗体评价;首次免疫后14和28 d采集猪血液,进行PRRSV实时荧光定量PCR(RT-qPCR)检测血液内是否存在PRRSV;统计试验猪分娩后头胎的活仔数、断奶仔猪数和窝均总仔数,进行临床数据比较分析。结果显示,35~50 kg体重阶段猪只接种疫苗后ELISA检测抗体水平增高较其他2个阶段更明显。混合疫苗组在免疫56 d时血清ELISA阳性率为100%,且ELISA结果极显著高于弱毒疫苗组和灭活疫苗组(P<0.01)。尽管各组没有产生特异性抗NADC30-like毒株的中和抗体,但针对PRRSV经典和高致病性毒株的中和抗体保护效价结果显示,混合疫苗组在免疫56 d时中和抗体效价极显著高于弱毒疫苗组和灭活疫苗组(P<0.01);RT-qPCR检测未发现阳性猪;各组试验猪分娩后头胎的活仔数、断奶仔猪数和窝均总仔数之间差异不显著(P>0.05)。结果表明,混合疫苗组对体液免疫的促进效果显著优于弱毒疫苗组和灭活疫苗组。该试验为临床正确选择PRRS疫苗免疫方案提供了科学数据。

Multi-valent mRNA vaccines against monkeypox enveloped or mature viron surface antigens demonstrate robust immune response and neutralizing activity

Monkeypox was declared a global health emergency by the World Health Organization,and as of March 2023,86,000 confirmed cases and 111 deaths across 110 countries have been reported.Its causal agent,monkeypox virus(MPV)belongs to a large family of double-stranded DNA viruses,Orthopoxviridae,that also includes vaccinia virus(VACV)and others.MPV produces two distinct forms of viral particles during its replication cycles:the enveloped viron(EV)that is released via exocytosis,and the mature viron(MV)that is discharged through lysis of host cells.This study was designed to develop multi-valent m RNA vaccines against monkeypox EV and MV surface proteins,and examine their efficacy and mechanism of action.Four m RNA vaccines were produced with different combinations of surface proteins from EV(A35R and B6R),MV(A29L,E8L,H3L and M1R),or EV and MV,and were administered in Balb/c mice to assess their immunogenicity potentials.A dynamic immune response was observed as soon as seven days after initial immunization,while a strong Ig G response to all immunogens was detected with ELISA after two vaccinations.The higher number of immunogens contributed to a more robust total Ig G response and correlating neutralizing activity against VACV,indicating the additive potential of each immunogen in generating immune response and nullifying VACV infection.Further,the m RNA vaccines elicited an antigen-specific CD4^(+)T cell response that is biased towards Th1.The m RNA vaccines with different combinations of EVand MV surface antigens protected a mouse model from a lethal dose VACV challenge,with the EV and MV antigens-combined vaccine offering the strongest protection.These findings provide insight into the protective mechanism of multi-valent m RNAvaccines against MPV,and also the foundation for further development of effective and safe m RNA vaccines for enhanced protection against monkeypox virus outbreak.

人用H5N1禽流感疫苗免疫动物效果观察

目的将用禽流感毒种R1203株按3种生产工艺生产的疫苗进行动物接种,观察疫苗的免疫效果。方法用不同剂量的3种工艺生产的禽流感疫苗,分别免疫大鼠和家兔,肌肉接种2针(隔14 d),首针后14和28 d静脉采血,测定接种1针和2针后,动物血清中血凝抑制抗体和中和抗体的产生情况。结果大鼠的抗体反应较家兔敏感;大鼠和家兔在疫苗接种1针后14 d,都能产生血抑抗体,滴度可达1∶40,但中和抗体滴度都很低,几乎测不到;接种2针后,血抑抗体或中和抗体反应都显著高于第1针;裂解-2苗接种大鼠和家兔后的抗体反应普遍高于另2种疫苗,且家兔量-效反应明显。结论裂解-2疫苗优于其他2种;中和抗体能正确反应疫苗的质量;H5N1禽流感疫苗的效力试验可用于免疫家兔测定中和抗体和临床前研究的动物试验,用15μg血凝素(HA)接种家兔2针,血清中和抗体滴度达1:40或以上。

用双价肾综合征出血热灭活疫苗加强接种HNT型单价疫苗免疫者的效果观察

对１９８８年经过ＨＮＴ型疫苗初免３针，并于１９８９年加强１针的７名志愿者，于１９９７年加强１针双价疫苗后１４天采血，测定对ＨＮＴ型和ＳＥＯ型ＨＦＲＳ病毒的中和抗体。结果经加强双价疫苗的７名志愿者血清中，均检出ＨＮＴ型和ＳＥＯ型病毒的中和抗体，其中对ＨＮＴ病毒的中和抗体较高，对ＳＥＯ型病毒的中和抗体也能达到规定的要求，表明双价ＨＦＲＳ灭活疫苗可用于过去接种ＨＮＴ型疫苗人群的加强。

肾综合征出血热沙鼠肾灭活疫苗的免疫持久性观察

目的：观察肾综合征出血热（HFRS）沙鼠肾灭活疫苗的免疫持久性。方法：采用空斑减少中和试验检测静脉血中和抗体。结果：初免3针后中和抗体阳转率达90％左右，但持续时间不长，一年后降至30％加强1针免疫后则持续时间较长,6年后仍为50％左右。结论：此疫苗近期免疫效果较好，加强免疫十分必要。

Sabin株脊髓灰质炎灭活疫苗对大鼠的免疫效果

目的比较不同浓度Sabin株脊髓灰质炎灭活疫苗(Sabin IPV)3针免疫大鼠的中和抗体效价,为确定Sabin IPV的最佳免疫方案提供参考。方法用不同浓度的Sabin IPV对52只Wistar大鼠进行3针免疫,每针间隔1个月,每次免疫后30d采血并分离血清,采用微量中和试验测定血清中抗脊髓灰质炎病毒3个型的中和抗体效价。结果大鼠经3针Sabin IPV免疫后,其Ⅰ、Ⅱ、Ⅲ型脊髓灰质炎病毒中和抗体的几何平均滴度均显著上升,2针免疫后抗体阳转率已经达到100%,且原倍疫苗与稀释疫苗免疫大鼠后,产生的中和抗体水平差异有显著意义。结论Sabin IPV在大鼠中有良好的免疫效果,经3针免疫可产生高水平的中和抗体。

丙型肝炎病毒疫苗的评价及研究进展

丙型肝炎病毒(hepatitis C virus,HCV)感染导致全球严重的疾病负担。虽然相关疾病的治疗药物已取得了突破性进展,但高昂的价格使得用药覆盖率成为难题。疫苗是控制HCV感染相关疾病的根本途径。现就HCV疫苗的评价及研究进展作一概述。

艾滋病疫苗与免疫

艾滋病(获得性免疫缺陷综合征)是由感染性艾滋病病毒所引起严重危害人类健康的疾病,它是一种病死率高、传播途径广的传染性疾病。艾滋病病毒通过攻击CD4+T细胞来破坏机体的免疫系统,研制出艾滋病疫苗是控制此病的最有效手段,而目前的研究成果并不理想,仍需要进一步探究免疫系统与艾滋病的发生发展间的相互作用。

丙型肝炎疫苗的研究进展

丙型肝炎是由丙型肝炎病毒(HepatitisCvirus,HCV)感染而引起的严重威胁人类健康的传染病,目前还没有研制成功有效的预防性疫苗,HCV基因组的高度变异及缺乏易感动物模型一直是妨碍丙肝疫苗发展的瓶颈。随着对HCV免疫清除机制的逐渐认识,诱导交叉反应性中和抗体和细胞免疫应答已成为丙肝疫苗研究的基本方向。本文概述了免疫应答在控制HCV感染过程中的作用以及当前丙肝疫苗的研究策略,并分析了丙肝疫苗的发展前景。

云贵川三省部分地区警犬狂犬病血清中和抗体调查

为评价警犬的狂犬病免疫效果,了解影响免疫效果的因素,2017年在云南、贵州、四川三省部分地区免疫狂犬病疫苗的警犬中随机抽样,采用荧光抗体病毒中和试验(FAVN),检测血清中狂犬病病毒中和抗体效价。结果显示,共抽检187只警犬,中和抗体阳性127只(≥0.50 IU/m L),总体免疫合格率为67.91%,其中云南、贵州、四川3省的免疫合格率分别为57.14%、68.33%、76.06%。结果分析表明,警犬狂犬病免疫合格率与犬的年龄、免疫次数、疫苗类型等因素有关,而与性别和品种无关。建议完善警犬免疫程序,加大血清中和抗体监测力度,对不合格警犬及时加强免疫;对每个影响因素进行连续性分析,以确定影响警犬狂犬病免疫合格率的具体因素。

玉树牦牛O型、Asial型口蹄疫疫苗免疫抗体效价分析

[目的]为预防控制牦牛口蹄疫病提供参考,对玉树部分县牦牛口蹄疫疫苗免疫状况进行了抗体水平调查。[方法]实验采用O型、Asial型口蹄疫抗体检测液相阻断ELISA法对306头牦牛血清进行O型、Asial型口蹄疫二联疫苗抗体水平检测。[结果]表明:囊谦、称多、杂多、治多四县牦牛口蹄疫O型、Asial型疫苗抗体具有50.00%以上保护力的比例分别为:90%、86.33%。玉树地区口蹄疫免疫状况良好,但各县之间免疫情况存在较大差异,治多、杂多两县口蹄疫抗体水平较低。

猪塞尼卡谷病毒病灭活疫苗免疫持续期测定

旨在研究猪塞尼卡谷病毒病灭活疫苗的免疫持续期。将两批实验室制品颈部肌肉注射2~3月龄健康猪,2.0 mL/头,免疫后21 d加强免疫1次,首次免疫后7、14、21、28、35、50、80、110、140、170、200 d分别采血,测定塞尼卡谷病毒(SVV)中和抗体效价,并于170 d和200 d分别随机抽取5头猪进行攻毒,以攻毒保护率均高于80%的最长免疫时间确定为疫苗的免疫持续期。免疫时间从第一次免疫后开始计算。结果显示,两批实验室制品免疫后7 d血清SVV中和抗体效价平均达1∶10以上;免疫后21 d中和抗体平均达1∶82.5以上;免疫后50 d血清抗体达到顶峰,中和抗体平均达1∶938.4以上。之后抗体呈下降趋势。免疫后170 d中和抗体平均达1∶192.1以上,免疫后200 d中和抗体平均达1∶73.8以上。免疫后170和200 d攻毒,保护率均达100%。试验结果说明,猪塞尼卡谷病毒灭活疫苗免疫期至少可维持到200 d,具有重要研发前景。

HIV-1/AIDS vaccine development： are we in the darkness before the dawn？

The pandemic of human immunodeficiency virus type 1 （HIV-I） has been devastating for the last two decades in a number of developing countries and constituting a grand challenge to the public health. WHO/UNAIDS estimates that approximately 33.2 million people were living with HIV-1 infection by the end of 2007 and almost 2.5 million new infections occurred in 2007. An unprecedented scientific challenge for the AIDS vaccine community is how to develop an effective HIV vaccine that can block HIV transmission and consequently stop the continuing spread of HIV-1. The recent failure of Merck Phase II B trial alerted the HIV vaccine community that new vaccine strategies need to be more exclusively explored. In this review, we outline the basics of HIV vaccine and retrospect the history of the road to HIV vaccine in last two decades, and highlight the challenges we are currently facing and new strategies to develop HIV vaccines in this field.

Efficient Humoral and Cellular Immune Responses Induced by a Chimeric Virus-like Particle Displaying the Epitope of EV71 without Adjuvant

Objective To eliminate the side effects of aluminum adjuvant and His-tag,we constructed chimeric VLPs displaying the epitope of EV71（SP70） without His-tagged.Then evaluating whether the VLPs could efficiently evoke not only humoral but also cellular immune responses against EV71 without adjuvant.Methods The fusion protein was constructed by inserting SP70 into the MIR of truncated HBc Ag sequence,expressed in E.Coli,and purified through ion exchange chromatography and density gradient centrifugation.Mice were immunized with the VLPs and sera were collected afterwards.The specific antibody titers,Ig G subtypes and neutralizing efficacy were detected by ELISA,neutralization assay,and EV71 lethal challenge.IFN-γ and IL-4 secreted by splenocytes were tested by ELISPOT assay.Results HBc-SP70 proteins can self-assemble into empty VLPs.After immunization with HBc-SP70 VLPs,the detectable anti-EV71 antibodies were effective in neutralizing EV71 and protected newborn mice from EV71 lethal challenge.There was no significant difference for the immune efficacy whether the aluminum adjuvant was added or not.The specific Ig G subtypes were mainly IgG1 and IgG2 b and splenocytes from the mice immunized produced high levels of IFN-γ and IL-4.Conclusion The fusion proteins without His-tagged was expressed and purified as soluble chimeric HBc-SP70 VLPs without renaturation.In the absence of adjuvant,they were efficient to elicit high levels of Th1/Th2 mixed immune response as well as assisted by aluminum adjuvant.Furthermore,the chimeric VLPs have potential to prevent HBV and EV71 infection simultaneously.

抗人类免疫缺陷病毒1型广谱中和抗体的研究进展

现行抗反转录病毒治疗药物的联合应用可有效抑制艾滋病进程并显著延长患者寿命,但由于人类免疫缺陷病毒1型(human immunodeficiency virus type 1,HIV-1)潜伏库的存在,艾滋病迄今尚无法治愈。近年发现抗HIV广谱中和抗体能有效降低患者体内病毒载量并延缓疾病进程,为研发艾滋病疫苗和治愈策略带来了曙光,尤其是序贯免疫策略的使用极大推进了广谱中和抗体的开发和应用进程。2018年,美国食品药品管理局(Food and Drug Administration,FDA)批准了第1个临床应用的广谱中性单克隆和抗体,无疑为抗HIV单克隆抗体药物的研发注入了一支强心剂。本文围绕近年来抗HIV广谱中和抗体的研究进展进行综述,探讨未来广谱中和抗体研发面临的挑战。

Immunogenicity and reactogenicity of heterologous immunization schedules with COVID-19 vaccines:a systematic review and network meta-analysis

Background:Data on the immunogenicity and safety of heterologous immunization schedules are inconsistent.This study aimed to evaluate the immunogenicity and safety of homologous and heterologous immunization schedules.Methods:Multiple databases with relevant studies were searched with an end date of October 31,2021,and a website including a series of Coronavirus disease 2019 studies was examined for studies before March 31,2022.Randomized controlled trials(RCTs)that compared different heterologous and homologous regimens among adults that reported immunogenicity and safety outcomes were reviewed.Primary outcomes included neutralizing antibodies against the original strain and serious adverse events(SAEs).A network meta-analysis(NMA)was conducted using a random-effects model.Results:In all,11 RCTs were included in the systematic review,and nine were ultimately included in the NMA.Among participants who received two doses of CoronaVac,another dose of mRNA or a non-replicating viral vector vaccine resulted in a significantly higher level of neutralizing antibody than a third CoronaVac 600 sino unit(SU);a dose of BNT162b2 induced the highest geometric mean ratio(GMR)of 15.24,95%confidence interval[CI]:9.53–24.39.Following one dose of BNT162b2 vaccination,a dose of mRNA-1273 generated a significantly higher level of neutralizing antibody than BNT162b2 alone(GMR=1.32;95%CI:1.06–1.64),NVX-CoV2373(GMR=1.60;95%CI:1.16–2.21),or ChAdOx1(GMR=1.80;95%CI:1.25–2.59).Following one dose of ChAdOx1,a dose of mRNA-1273 was also more effective for improving antibody levels than ChAdOx1(GMR=11.09;95%CI:8.36–14.71)or NVX-CoV2373(GMR=2.87;95%CI:1.08–3.91).No significant difference in the risk for SAEs was found in any comparisons.Conclusions:Relative to vaccination with two doses of CoronaVac,a dose of BNT162b2 as a booster substantially enhances immunogenicity reactions and has a relatively acceptable risk for SAEs relative to other vaccines.For primary vaccination,schedules including mRNA vaccines induce a greater immune response.However,the comparatively higher risk for local and systemic adverse events introduced by mRNA vaccines should be noted.Registration:PROSPERO;https://www.crd.york.ac.uk/PROSPERO/;No.CRD42021278149.

Exploration of a Sequential Gp140-Gp145 Immunization Regimen with Heterologous Envs to Induce a Protective Cross-Reactive HIV Neutralizing Antibody Response In Non-human Primates

Raising a heterologous tier 2 neutralizing antibody(nAb)response remains a daunting task for HIV vaccine development.In this study,we explored the utility of diverse HIV-1 envelope(Env)immunogens in a sequential immunization scheme as a solution to this task.This exploration stemmed from the rationale that gp145,a membrane-bound truncation form of HIV Env,may facilitate the focusing of induced antibody response on neutralizing epitopes when sequentially combined with the soluble gp140 form as immunogens in a prime-boost mode.We first showed that gp140 DNA prime-gp145 Tiantan vaccinia(TV)boost likely represents a general format for inducing potent nAb response in mice.However,when examined in rhesus macaque,this modality showed little effectiveness.To improve the efficacy,we extended the original modality by adding a strong protein boost,namely native-like SOSIP.664 trimer displayed on ferritin-based nanoparticle(NP),which was generated by a newly developed click approach.The resulting three-immunization regimen succeeded in eliciting tier-2 nAb response with substantial breadth when implemented in rhesus macaque over a short 8-week schedule.Importantly,the elicited nAb response was able to effectively contain viremia upon a heterologous SHIV challenge.Collectively,our studies highlighted that diversification of Env immunogens,in both types and formulations,under the framework of a sequential immunization scheme might open new opportunity toward HIV vaccine development.

国产脊髓灰质炎糖丸与进口液体疫苗免疫后的血清学效果观察

为比较脊髓灰质炎国产糖丸疫苗与进口液体疫苗基础免疫血清学效果，对102名2～12月龄婴儿，随机分为两组分别全程接种两种疫苗后，检测血清中和抗体的阳性率和几何平均滴度（GMRT）．结果显示两种疫苗和各型别中和抗体阳性率均达80％以上，且两苗型间无显著差别，但免疫后Ⅲ型抗体GMRT水平，糖丸疫苗组显著高于液体疫苗组，说明两种疫苗虽均能获得良好的免疫效果，但国产糖丸疫苗更优于进口液体疫苗。