Ferritin nanoparticle-based Nipah virus glycoprotein vaccines elicit potent protective immune responses in mice and hamsters.

Nipah virus (NiV) is a zoonotic paramyxovirus in the genus Henipavirus that is prevalent in Southeast Asia. NiV leads to severe respiratory disease and encephalitis in humans and animals, with a mortality rate of up to 75%. Despite the grave threat to public health and global biosecurity, no medical countermeasures are available for humans. Here, based on self-assembled ferritin nanoparticles (FeNPs), we successfully constructed two candidate FeNP vaccines by loading mammalian cells expressing NiV sG (residues 71-602, FeNP-sG) and Ghead (residues 182-602, FeNP-Ghead) onto E. coli-expressed FeNPs (FeNP-sG and FeNP-Ghead, respectively) through Spycatcher/Spytag technology. Compared with sG and Ghead alone, FeNP-sG and FeNP-Ghead elicited significant NiV specific neutralizing antibody levels and T-cell responses in mice, whereas the immune response in the FeNP-sG immunized group was greater than that in the FeNP-Ghead group. These results further demonstrate that sG possesses greater antigenicity than Ghead and that FeNPs can dramatically enhance immunogenicity. Furthermore, FeNP-sG provided 100% protection against NiV challenge in a hamster model when it was administered twice at a dose of 5 µg/per animal. Our study provides not only a promising candidate vaccine against NiV, but also a theoretical foundation for the design of a NiV immunogen for the development of novel strategies against NiV infection.

Three-directional digital shearography based on SLM using a honeycomb-like pattern.

The possibility of utilizing a honeycomb-like modulation pattern in a spatial light modulator (SLM) for multi-directional synchronous digital shearography measurements has been investigated. Each modulation pixel in the honeycomb-like pattern modulates the shearing amount in different directions, thus avoiding the resolution loss associated with previous methods where a single pixel could only modulate a specific shearing direction. It was demonstrated that high-quality phase maps for different shearing directions can be simultaneously obtained with a single exposure.

An attachment glycoprotein nanoparticle elicits broadly neutralizing antibodies and protects against lethal Nipah virus infection.

Nipah virus (NiV) is a zoonotic emergent paramyxovirus that can cause severe encephalitis and respiratory infections in humans, with a high fatality rate ranging from 40% to 75%. Currently, there are no approved human vaccines or antiviral drugs against NiV. Here, we designed a ferritin-based self-assembling nanoparticle displaying the NiV G head domain on the surface (NiV G-ferritin) and assessed immune responses elicited by the soluble NiV G head domain (NiV sG) or NiV G-ferritin. Immunization with NiV G-ferritin or NiV sG conferred complete protection against lethal NiV challenge without detection of viral RNA in Syrian golden hamsters. Compared to NiV sG, NiV G-ferritin induced significantly faster, broader, and higher serum neutralizing responses against three pathogenic henipaviruses (NiV-Malaysia, NiV-Bangladesh, and Hendra virus). Moreover, NiV G-ferritin induced a durable neutralizing immunity in mice as antisera potently inhibited NiV infection even after six months of the third immunization. Additionally, we isolated a panel of 27 NiV G-binding monoclonal antibodies (mAbs) from NiV G-ferritin immunized mice and found that these mAbs targeted four distinct antigenic sites on NiV G head domain with two sites that have not been defined previously. Notably, 25 isolated mAbs have potent neutralizing activity with 50% inhibitory concentrations less than 10 ng/mL against NiV pseudovirus. Collectively, these findings provide new insights into the immunogenicity of NiV G protein and reveal that NiV G-ferritin is a safe and highly effective vaccine candidate against Nipah virus infection.

A potent Henipavirus cross-neutralizing antibody reveals a dynamic fusion-triggering pattern of the G-tetramer.

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.

Potent human neutralizing antibodies against Nipah virus derived from two ancestral antibody heavy chains.

Nipah virus (NiV) is a World Health Organization priority pathogen and there are currently no approved drugs for clinical immunotherapy. Through the use of a naïve human phage-displayed Fab library, two neutralizing antibodies (NiV41 and NiV42) targeting the NiV receptor binding protein (RBP) were identified. Following affinity maturation, antibodies derived from NiV41 display cross-reactivity against both NiV and Hendra virus (HeV), whereas the antibody based on NiV42 is only specific to NiV. Results of immunogenetic analysis reveal a correlation between the maturation of antibodies and their antiviral activity. In vivo testing of NiV41 and its mature form (41-6) show protective efficacy against a lethal NiV challenge in hamsters. Furthermore, a 2.88 Å Cryo-EM structure of the tetrameric RBP and antibody complex demonstrates that 41-6 blocks the receptor binding interface. These findings can be beneficial for the development of antiviral drugs and the design of vaccines with broad spectrum against henipaviruses.

Preclinical evaluation of RQ3013, a broad-spectrum mRNA vaccine against SARS-CoV-2 variants.

The global emergence of SARS-CoV-2 variants has led to increasing breakthrough infections in vaccinated populations, calling for an urgent need to develop more effective and broad-spectrum vaccines to combat COVID-19. Here we report the preclinical development of RQ3013, an mRNA vaccine candidate intended to bring broad protection against SARS-CoV-2 variants of concern (VOCs). RQ3013, which contains pseudouridine-modified mRNAs formulated in lipid nanoparticles, encodes the spike (S) protein harboring a combination of mutations responsible for immune evasion of VOCs. Here we characterized the expressed S immunogen and evaluated the immunogenicity, efficacy, and safety of RQ3013 in various animal models. RQ3013 elicited robust immune responses in mice, hamsters, and nonhuman primates (NHP). It can induce high titers of antibodies with broad cross-neutralizing ability against the wild-type, B.1.1.7, B.1.351, B.1.617.2, and the newly emerging Omicron variants. In mice and NHP, two doses of RQ3013 protected the upper and lower respiratory tract against infection by SARS-CoV-2 and its variants. Furthermore, our safety assessment of RQ3013 in NHP showed no observable adverse effects. These results provide strong support for the evaluation of RQ3013 in clinical trials and suggest that it may be a promising candidate for broad protection against COVID-19 and its variants.

Vaccines based on the fusion protein consensus sequence protect Syrian hamsters from Nipah virus infection.

Nipah virus (NiV), a bat-borne paramyxovirus, results in neurological and respiratory diseases with high mortality in humans and animals. Developing vaccines is crucial for fighting these diseases. Previously, only a few studies focused on the fusion (F) protein alone as the immunogen. Numerous NiV strains have been identified, including 2 representative strains from Malaysia (NiV-M) and Bangladesh (NiV-B), which differ significantly from each other. In this study, an F protein sequence with the potential to prevent different NiV strain infections was designed by bioinformatics analysis after an in-depth study of NiV sequences in GenBank. Then, a chimpanzee adenoviral vector vaccine and a DNA vaccine were developed. High levels of immune responses were detected after AdC68-F, pVAX1-F, and a prime-boost strategy (pVAX1-F/AdC68-F) in mice. After high titers of humoral responses were induced, the hamsters were challenged by the lethal NiV-M and NiV-B strains separately. The vaccinated hamsters did not show any clinical signs and survived 21 days after infection with either strain of NiV, and no virus was detected in different tissues. These results indicate that the vaccines provided complete protection against representative strains of NiV infection and have the potential to be developed as a broad-spectrum vaccine for human use.

Both chimpanzee adenovirus-vectored and DNA vaccines induced long-term immunity against Nipah virus infection.

Nipah virus (NiV) is a highly lethal zoonotic paramyxovirus that poses a severe threat to humans due to its high morbidity and the lack of viable countermeasures. Vaccines are the most crucial defense against NiV infections. Here, a recombinant chimpanzee adenovirus-based vaccine (AdC68-G) and a DNA vaccine (DNA-G) were developed by expressing the codon-optimized full-length glycoprotein (G) of NiV. Strong and sustained neutralizing antibody production, accompanied by an effective T-cell response, was induced in BALB/c mice by intranasal or intramuscular administration of one or two doses of AdC68-G, as well as by priming with DNA-G and boosting with intramuscularly administered AdC68-G. Importantly, the neutralizing antibody titers were maintained for up to 68 weeks in the mice that received intramuscularly administered AdC68-G and the prime DNA-G/boost AdC68-G regimen, without a significant decline. Additionally, Syrian golden hamsters immunized with AdC68-G and DNA-G via homologous or heterologous prime/boost immunization were completely protected against a lethal NiV virus challenge, without any apparent weight loss, clinical signs, or pathological tissue damage. There was a significant reduction in but not a complete absence of the viral load and number of infectious particles in the lungs and spleen tissue following NiV challenge. These findings suggest that the AdC68-G and DNA-G vaccines against NiV infection are promising candidates for further development.

Rapid one-shot dual-shearing digital shearography using a spatial light modulator.

Digital shearography is a non-contact, whole-field, and high-accuracy laser-based optical interferometric method. It is widely used in the field of non-destructive testing and material evaluation. Dual-shearing DS, as the state-of-the-art method, can detect defects or measure the derivative of deformation in two sensitive directions. Most existing dual-shearing DS is realized with a bulky Michelson or Mach-Zehnder interferometer; recently, the usage of a spatial light modulator (SLM) in DS offers a new approach to designing a simple and light shearographic system. However, prior proposed SLM-based DS requires multiple shots for the phase map acquisition, with the classic temporal phase-shift (TPS) technique severely limiting its applications. This paper proposes a novel, to our best knowledge, one-shot dual-shearing DS by creating a dual-stripe pattern in the SLM. Two separate phase maps, with different sensitive directions, were acquired simultaneously via the spatial phase-shift technique. The measurement can be easily done within a single shot in its compact and light body. Moreover, the shearing amount of the two sensitive directions can be set independently and precisely. These advantages promote that the proposed system can be applied in various applications, especially for dynamic and complicated composite material testing. A detailed theory and experimental validation are described.

Increased pathogenicity and aerosol transmission for one SARS-CoV-2 B.1.617.2 Delta variant over the wild-type strain in hamsters.

During the two-year pandemic of coronavirus disease 2019 (COVID-19), its causative agent, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has been evolving. SARS-CoV-2 Delta, a variant of concern, has become the dominant circulating strain worldwide within just a few months. Here, we performed a comprehensive analysis of a new B.1.617.2 Delta strain (Delta630) compared with the early WIV04 strain (WIV04) in vitro and in vivo, in terms of replication, infectivity, pathogenicity, and transmission in hamsters. When inoculated intranasally, Delta630 led to more pronounced weight loss and more severe disease in hamsters. Moreover, 40% mortality occurred about one week after infection with 104 â€‹PFU of Delta630, whereas no deaths occurred even after infection with 105 â€‹PFU of WIV04 or other strains belonging to the Delta variant. Moreover, Delta630 outgrew over WIV04 in the competitive aerosol transmission experiment. Taken together, the Delta630 strain showed increased replication ability, pathogenicity, and transmissibility over WIV04 in hamsters. To our knowledge, this is the first SARS-CoV-2 strain that causes death in a hamster model, which could be an asset for the efficacy evaluation of vaccines and antivirals against infections of SARS-CoV-2 Delta strains. The underlying molecular mechanisms of increased virulence and transmission await further analysis.

A study of subtropical park thermal comfort and its influential factors during summer.

Outdoor thermal comfort is significantly relevant to human's quality of life. Thus, it has been frequently studied by investigators. This study explored people's thermal responses to environments and the subjective factors that might affect thermal comforts with respect to two urban parks in Xindu, a satellite city in the Chengdu Plain (CDP). CDP is located at the southwest of China, which has a subtropical climate. The environment from each of the two parks was studied using current micrometeorology and hoped-for landscape changes (tree canopies, artificial canopies, non-canopying plants, and water surfaces); subjective factors included gender, age, body mass index, clothing isolation, and physical activities. It was found that canopies were the most preferred objective cooling elements, while individual thermal perceptions varied subjectively by age. The highest proportion of volunteers voted for tree canopies as their favourite thermal adjusting element. It was observed that those aged above 55 showed low thermal sensitivity. The remaining group's neutral temperatures (indicated by physiologically equivalent temperature, PET) were close, at approximately 25 °C. This study provides significant direction for future urban planning and landscape design.

A randomized controlled trial of bedside ultrasound RUSH process to improve the quality of anesthesia for elderly emergency surgery patients.

Objectives: The rapid ultrasound in shock examination (RUSH process) is an assessment of patient's heart function, volume status, and vasculature, which can help anesthesiologist understand the patient's physical condition. In this study, the RUSH process was applied to elderly emergency surgery patients to evaluate whether it is beneficial to maintain the patient's vital signs stable during the operation. Methods: In this randomized controlled clinical study one hundred elderly patients who needed general anesthesia and emergency surgery from January 2021 to July 2021 were randomly divided into RUSH group (Group-A, n=52) and control group (Group-B, n=48). The main result include the area under the intraoperative blood pressure curve (AUC), liquid input, urine output, lactic acid levels, number of vasoactive drugs used. Results: There were no significant differences in patients' basic information, preoperative blood pressure, intraoperative blood loss, intraoperative fluid input, intraoperative blood transfusion, and urine output. Intraoperative systolic blood pressure less than 90mmHg AUC of Group-A is less than Group-B(P<0.05), diastolic blood pressure less than 60mmHg AUC of Group-A is less than Group-B(P<0.05). After the operation, the blood gas analysis lactic acid level in Group-A was lower than that in Group-B(P<0.05). Group-A used more vasoactive drugs than Group-B(P<0.05). Conclusion: The bedside ultrasound RUSH process is of great significance for anesthesiologist to understand the preoperative physical condition of elderly emergency surgery patients, and is beneficial to maintain the stability of intraoperative vital signs.

Evidence for Water-Borne Transmission of Highly Pathogenic Avian Influenza H5N1 Viruses.

In this study, we isolated 10 H5N1 strains from water samples in Dongting Lake and 4 H5N1 strains from lakeside backyard poultry. These isolates belonged to three distinct clades (clade 2.3.2, 2.3.4, and 7). Phylogenetic analysis showed a diversified genome constellation. The genetic characteristics of some viruses isolated from water samples were extremely similar to those from lakeside poultry. Pathogenic experiments showed that selected represented isolates in this study were highly pathogenic for SPF chickens but had a diversified virulence in mice. The results of our study suggested the potential transmission of avian influenza (H5N1) between the poultry and wild waterfowls and water body around the habitat may play an important role.

Recombinant chimpanzee adenovirus vector vaccine expressing the spike protein provides effective and lasting protection against SARS-CoV-2 infection in mice.

SARS-CoV-2 infection is a global public health threat. Vaccines are considered amongst the most important tools to control the SARS-CoV-2 pandemic. As expected, deaths from SARS-CoV-2 infection have dropped dramatically with widespread vaccination. However, there are concerns over the duration of vaccine-induced protection, as well as their effectiveness against emerging variants of concern. Here, we constructed a recombinant chimpanzee adenovirus vectored vaccine expressing the full-length spike of SARS-CoV-2 (AdC68-S). Rapid and high levels of humoral and cellular immune responses were observed after immunization of C57BL/6J mice with one or two doses of AdC68-S. Notably, neutralizing antibodies were observed up to at least six months after vaccination, without substantial decline. Single or double doses AdC68-S immunization resulted in lower viral loads in lungs of mice against SARS-CoV-2 challenge both in the short term (21 days) and long-term (6 months). Histopathological examination of AdC68-S immunized mice lungs showed mild histological abnormalities after SARS-CoV-2 infection. Taken together, this study demonstrates the efficacy and durability of the AdC68-S vaccine and constitutes a promising candidate for clinical evaluation.

mRNA based vaccines provide broad protection against different SARS-CoV-2 variants of concern.

In order to overcome the pandemic of COVID-19, messenger RNA (mRNA)-based vaccine has been extensively researched as a rapid and versatile strategy. Herein, we described the immunogenicity of mRNA-based vaccines for Beta and the most recent Omicron variants. The homologous mRNA-Beta and mRNA-Omicron and heterologous Ad5-nCoV plus mRNA vaccine exhibited high-level cross-reactive neutralization for Beta, original, Delta, and Omicron variants. It indicated that the COVID-19 mRNA vaccines have great potential in the clinical use against different SARS-CoV-2 variants.

RBD-homodimer, a COVID-19 subunit vaccine candidate, elicits immunogenicity and protection in rodents and nonhuman primates.

The pandemic of COVID-19 caused by SARS-CoV-2 has raised a new challenges to the scientific and industrious fields after over 1-year spread across different countries. The ultimate approach to end the pandemic is the timely application of vaccines to achieve herd immunity. Here, a novel SARS-CoV-2 receptor-binding domain (RBD) homodimer was developed as a SARS-CoV-2 vaccine candidate. Formulated with aluminum adjuvant, RBD dimer elicited strong immune response in both rodents and non-human primates, and protected mice from SARS-CoV-2 challenge with significantly reducing viral load and alleviating pathological injury in the lung. In the non-human primates, the vaccine could prevent majority of the animals from SARS-CoV-2 infection in the respiratory tract and reduce lung damage. In addition, antibodies elicited by this vaccine candidate showed cross-neutralization activities to SARS-CoV-2 variants. Furthermore, with our expression system, we provided a high-yield RBD homodimer vaccine without additional biosafety or special transport device supports. Thus, it may serve as a safe, effective, and low-cost SARS-CoV-2 vaccine candidate.