Herpes zoster remains an important global health issue and mainly occurs in aged and immunocompromised individuals with an early exposure history to Varicella Zoster Virus (VZV). Although the licensed vaccine Shingrix has a remarkably high efficacy, undesired reactogenicity and increasing global demand causing vaccine shortage urged the development of improved or novel VZV vaccines. In this study, we developed a novel VZV mRNA vaccine candidate (named as ZOSAL) containing sequence-optimized mRNAs encoding full-length glycoprotein E encapsulated in an ionizable lipid nanoparticle. In mice and rhesus macaques, ZOSAL demonstrated superior immunogenicity and safety in multiple aspects over Shingrix, especially in the induction of strong T cell immunity. Transcriptomic analysis revealed that both ZOSAL and Shingrix could robustly activate innate immune compartments, especially Type-I IFN signaling and antigen processing/presentation. Multivariate correlation analysis further identified several early factors of innate compartments that can predict the magnitude of T cell responses, which further increased our understanding of the mode of action of two different VZV vaccine modalities. Collectively, our data demonstrated the superiority of VZV mRNA vaccine over licensed subunit vaccine. The mRNA platform therefore holds prospects for further investigations in next-generation VZV vaccine development.

Viral-induced microbial mortality has been proposed as a major contributor in shaping microbial community structure and function, soil carbon (C) accrual and mobilization of plant available nutrients. Yet, how soil viruses influence soil organic C (SOC) turnover and sequestration remains unknown. Here, we performed microcosm experiments with two distinct soils from grassland (GL) and agricultural (AG) sites and interrogated the roles of soil viruses in driving microbial community succession, SOC transformation and sequestration. The results show that soil viruses affected microbial C use efficiency and reduced respiration in microbial communities obtained from both GL and AG soils. Soil viruses affected microbial successional trajectories (via predation of dominant populations) and functional gene profiles triggering a significant decrease in CO2 and N2O emissions. The impact of soil viruses on microbial community composition in GL microcosms was much less pronounced compared with that in AG microcosms, suggesting contrasting virus-host interaction patterns under different environmental settings. Viral infection significantly enhanced microbial necromass accumulation thereby increasing SOC and total nitrogen (TN) content. The results implicate viral-mediated microbial mortality as a key factor influencing the distribution of C between mineralization and soil C storage pathways. We proposed “viral loop” to explain the crucial function of soil viruses in SOC turnover and sequestration.### Competing Interest StatementThe authors have declared no competing interest.

Here we report on the development and comprehensive evaluations of an mRNA vaccine for chronic hepatitis B (CHB) treatment. In two different HBV carrier mouse models generated by viral vector-mediated HBV transfection (pAAV-HBV1.2 and rAAV8-HBV1.3), this vaccine demonstrates sufficient and persistent virological suppression, and robust immunogenicity in terms of induction of strong innate immune activation, high-level virus-specific antibodies, memory B cells and T cells. mRNA platform therefore holds prospects for therapeutic vaccine development to combat CHB.

OBJECTIVE:The purpose of this study is to develop an anti-PDL1-based interferon (IFN) fusion protein to overcome the chronic hepatitis B virus (HBV)-induced immune tolerance, and combine this immunotherapy with a HBV vaccine to achieve the functional cure of chronic hepatitis B (CHB) infection.DESIGN:We designed an anti-PDL1-IFNα heterodimeric fusion protein, in which one arm was derived from anti-PDL1 antibody and the other arm was IFNα, to allow targeted delivery of IFNα into the liver by anti-PDL1 antibody. The effect of the anti-PDL1-IFNα heterodimer on overcoming hepatitis B surface antigen (HBsAg) vaccine resistance was evaluated in chronic HBV carrier mice.RESULTS:The anti-PDL1-IFNα heterodimer preferentially targeted the liver and resulted in viral suppression, the PD1/PDL1 immune checkpoint blockade and dendritic cell activation/antigen presentation to activate HBsAg-specific T cells, thus breaking immune tolerance in chronic HBV carrier mice. When an HBsAg vaccine was administered soon after anti-PDL1-IFNα heterodimer treatment, we observed strong anti-HBsAg antibody and HBsAg-specific T cell responses for efficient HBsAg clearance in chronic HBV carrier mice that received the combination treatment but not in those that received either single treatment.CONCLUSIONS:Targeting the liver with an engineered anti-PDL1-IFNα heterodimer can break HBV-induced immune tolerance to an HBsAg vaccine, offering a promising translatable therapeutic strategy for the functional cure of CHB.

A fourth dose of a COVID-19 vaccine has been recommended by a number of authorities due to waning immunity over time and the emergence of immune-escaping variants. Here, we evaluated the safety and immunogenicity of the bivalent BV-01-B5 or V-01D-351 or the prototype V-01 for heterologous boosting in three-dose inactivated COVID-19 vaccine (ICV) recipients, in comparison with ICV homologous boosting. One pilot study (NCT05583357) included 20 participants randomized at 1:1, either receiving V-01D-351 or CoronaVac. The other one (NCT05585567) recruited 36 participants randomized at 2:1, either receiving BV-01-B5 or V-01, respectively. BV-01-B5, V-01D-351, and V-01 were safe and well-tolerated as heterologous booster shots after three doses of ICV, with adverse reactions predominantly being mild and moderate in severity, similar to the safety profile of ICV boosters. The bivalent V-01D-351 and BV-01-B5 and prototype V-01 booster demonstrated remarkable cross-reactive immunogenicity against the prototype and multiple emerging variants of concern (VOCs), with the geometric mean ratio (versus CoronaVac) in particular being 31.3 (500 vs. 16), 12.0 (192 vs. 16) and 8.5 (136 vs.16) against BA.4/5 14 days after the booster, respectively. Taken together, the modified bivalent-formulation V-01 boosters induced robust neutralizing responses against multiple Omicron sublineages, better than V-01 and remarkably superior to ICV booster, without compromising the safety and tolerability.

目的 构建针对新型冠状病毒的重组核酸苗,评价其与佐剂联合免疫BALB/c小鼠的效果.方法 选择新型冠状病毒S蛋白的受体结合域蛋白基因(RBD)和新冠病毒S、M、N、E 4个结构蛋白的抗原表位基因(EPI)为主要抗原基因,以pVAX1为载体,分别构建pVAX-RBD-EPI质粒和pVAX-RBD质粒.用2种重组质粒和pVAX空载体质粒分别与PIKCA佐剂联合免疫或无佐剂免疫BALB/c小鼠,共免疫3次,间隔21天免疫,每7 d对小鼠特异性抗体进行检测;对三免后21 d小鼠脾淋巴细胞进行T淋巴细胞亚类检测.结果 成功构建了重组质粒pVAX-RBD-EPI和pVAX-RBD.用重组质粒转染BHK细胞,Western blot显示重组核酸质粒稳定表达目的蛋白.BALB/c小鼠免疫结果表明,三免后14d时pVAX-RBD-EPI+PIKCA组IgG抗体水平为无佐剂组的3.65倍(P＜0.01).三免后21 d,pVAX-RBD-EPI+PIKCA 组 CD3+/CD4+T 达到55.71％,是阴性对照组的 1.52倍(P＜0.01);三免后21 d,CD3+/CD8+T 数量 pVAX-RBD-EPI+PIKCA组为7.07％,是阴性对照组的 1.83倍,是 pVAX-RBD-EPI 组(5.86％)的 1.2倍(P＜0.05).结论 成功构建重组DNA候选疫苗pVAX-RBD-EPI和pVAX-RBD-EPI.两种疫苗均具有良好的免疫原性,其中PIKCA免疫佐剂的加入可增强小鼠细胞免疫和体液免疫水平.

The wide spread of coronavirus disease 2019 (COVID-19) has significantly threatened public health. Human herd immunity induced by vaccination is essential to fight the epidemic. Therefore, highly immunogenic and safe vaccines are necessary to control SARS-CoV-2, whose S protein is the antigenic determinant responsible for eliciting antibodies that prevent viral entry and fusion. In this study, we developed a SARS-CoV-2 DNA vaccine expressing the S protein, named pVAX-S-OP, which was optimized according to the human-origin codon preference and using polyinosinic-polycytidylic acid as an adjuvant. pVAX-S-OP induced specific antibodies and neutralizing antibodies in BALB/c and hACE2 transgenic mice. Furthermore, we observed 1.43-fold higher antibody titers in mice receiving pVAX-S-OP plus adjuvant than in those receiving pVAX-S-OP alone. Interferon gamma production in the pVAX-S-OP-immunized group was 1.58 times (CD3+CD4+IFN-gamma+) and 2.29 times (CD3+CD8+IFN-gamma+) lower than that in the pVAX-S-OP plus adjuvant group but higher than that in the control group. The pVAX-S-OP vaccine was also observed to stimulate a Th1-type immune response. When, hACE2 transgenic mice were challenged with SARS-CoV-2, qPCR detection of N and E genes showed that the viral RNA loads in pVAX-S-OP-immunized mice lung tissues were 104 times and 106 times lower than those of the PBS control group, which shows that the vaccine could reduce the amount of live virus in the lungs of hACE2 mice. In addition, pathological sections showed less lung damage in the pVAX-S-OP-immunized group. Taken together, our results demonstrated that pVAX-S-OP has significant immunogenicity, which provides support for developing SARS-CoV-2 DNA candidate vaccines.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global crisis, urgently necessitating the development of safe, efficacious, convenient-to-store, and low-cost vaccine options. A major challenge is that the receptor-binding domain (RBD)-only vaccine fails to trigger long-lasting protective immunity if used alone for vaccination. To enhance antigen processing and cross-presentation in draining lymph nodes (DLNs), we developed an interferon (IFN)-armed RBD dimerized by an immunoglobulin fragment (I-R-F). I-R-F efficiently directs immunity against RBD to DLNs. A low dose of I-R-F induces not only high titers of long-lasting neutralizing antibodies (NAbs) but also more comprehensive T cell responses than RBD. Notably, I-R-F provides comprehensive protection in the form of a one-dose vaccine without an adjuvant. Our study shows that the pan-epitope modified human I-R-F (I-P-R-F) vaccine provides rapid and complete protection throughout the upper and lower respiratory tracts against a high-dose SARS-CoV-2 challenge in rhesus macaques. Based on these promising results, we have initiated a randomized, placebo-controlled, phase I/II trial of the human I-P-R-F vaccine (V-01) in 180 healthy adults, and the vaccine appears safe and elicits strong antiviral immune responses. Due to its potency and safety, this engineered vaccine may become a next-generation vaccine candidate in the global effort to overcome COVID-19.

构建抗登革病毒(dengue virus,DENV)人源化单克隆抗体,并对其表达及纯化.利用PDB数据库公布的鼠源抗DENV单克隆抗体1A1D的轻重链可变区氨基酸序列以及GenBank公布的人源抗体轻重链恒定区氨基酸序列,通过基因工程改造为抗DENV人源化单克隆抗体h1A1D,提取转染级质粒;轻重链质粒混合后转染CHO-K1细胞表达抗体,Protein A亲和介质进行抗体纯化,测定所得抗体蛋白质量浓度,SDS-PAGE蛋白电泳分析所获得人源化抗体的相对分子质量大小和纯度;Western blot检测其结合能力.结果 显示,构建抗DENV人源化单克隆抗体h1A1D轻链和重链的表达载体,在CHO-K1细胞中稳定表达后,经Protein A亲和介质纯化后,获得1株抗DENV人源化单克隆抗体h1A1D;纯化后抗体的蛋白质量浓度为1.42 g/L,SDS-PAGE电泳分析h1A1D二价抗体的轻重链大小分别为30,55 kDa,完整抗体约为190 kDa,能有效结合含有DENV 4种血清型的E基因的串联蛋白.结果 表明,成功构建抗DENV人源化单克隆抗体h1A1D,采用Protein A亲和介质纯化,为后期人源化单克隆抗体的制备纯化的研究奠定了基础,为DENV的机制研究以及抗体治疗药物的开发提供参考.

目的 设计抗H5N1亚型流感病毒的通用型mRNA疫苗,并完成候选疫苗的构建、表达及鉴定.方法 设计3组候选疫苗抗原基因,分别命名为Flu、Flu-ferritin和CD5-Flu-ferritin(Flu含H1/H3/H5/B型流感病毒血凝素颈部区保守表位,并串联甲型流感病毒M2e基因中保守序列;Flu-Ferrin在Flu后串联铁蛋白,用以形成多聚体;CD5为分泌型信号肽,将多聚体外泌).3组基因依次克隆至设计的mRNA疫苗骨架载体上,通过质粒鉴定、线性化处理、体外转录、纯化、及Cap 1加帽处理,分别制备mRNA并转染A549细胞,通过Western blot和IFA方法鉴定目的蛋白的表达.结果 成功构建3组mRNA候选疫苗,并在A549细胞上表达抗原蛋白.结论 证明了抗原设计的可行性,为开展动物试验奠定了基础.