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.

NSUN2 mediates distinct pathways to regulate enterovirus 71 replication.

Increasing evidences suggest that the methyltransferase NSUN2 catalyzes 5-methylcytosine (m5C) modifications on viral RNAs, which are essential for the replication of various viruses. Despite the function of m5C deposition is well characterized, other potential roles of NSUN2 in regulating viral replication remain largely unknown. In this study, the m5C modified residues catalyzed by NSUN2 on enterovirus 71 (EV71) RNAs were mapped.

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.

NS1-mediated enhancement of MVC transcription and replication promoted by KAT5/H4K12ac.

Histone modifications function in both cellular and viral gene expression. However, the roles of acetyltransferases and histone acetylation in parvoviral infection remain poorly understood. In the current study, we found the histone deacetylase (HDAC) inhibitor, trichostatin A (TSA), promoted the replication and transcription of parvovirus minute virus of canines (MVC).

Epigenetic addition of mC to HBV transcripts promotes viral replication and evasion of innate antiviral responses.

Eukaryotic five-methylcytosine (mC) is an important regulator of viral RNA splicing, stability, and translation. However, its role in HBV replication remains largely unknown. In this study, functional mC sites are identified in hepatitis B virus (HBV) mRNA.

Safety, immunogenicity, and efficacy of a modified COVID-19 mRNA vaccine, SW-BIC-213, in healthy people aged 18 years and above: a phase 3 double-blinded, randomized, parallel controlled clinical trial in Lao PDR (Laos).

Background: The mRNA vaccine has demonstrated significant effectiveness in protecting against SARS-CoV-2 during the pandemic, including against severe forms of the disease caused by emerging variants. In this study, we examined safety, immunogenicity, and relative efficacy of a heterologous booster of the lipopolyplex (LPP)-based mRNA vaccine (SW-BIC-213) versus a homologous booster of an inactivated vaccine (BBIBP) in Laos.

Methods: In this phase 3 clinical trial, which was randomized, parallel controlled and double-blinded, healthy adults aged 18 years and above were recruited from the Southern Savannakhet Provincial Hospital and Champhone District Hospital.

Subgenomic Flaviviral RNAs of Dengue Viruses.

Subgenomic flaviviral RNAs (sfRNAs) are produced during flavivirus infections in both arthropod and vertebrate cells. They are undegraded products originating from the viral 3' untranslated region (3' UTR), a result of the action of the host 5'-3' exoribonuclease, Xrn1, when it encounters specific RNA structures known as Xrn1-resistant RNAs (xrRNAs) within the viral 3' UTR. Dengue viruses generate three to four distinct species of sfRNAs through the presence of two xrRNAs and two dumbbell structures (DBs).

Genomic Surveillance of SARS-CoV-2 Variants That Emerged in South and Southeast Asia during Early 2022.

The continuously emerging new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have made the global coronavirus disease 2019 (COVID-19) pandemic unpredictable. Since the beginning of the pandemic, densely populated South and Southeast Asia have suffered great losses due to multiple COVID-19 surges because of vaccine and other medical resource shortages. Therefore, it is crucial to closely monitor the SARS-CoV-2 epidemic and to understand the evolutionary and transmission characteristics of SARS-CoV-2 in these regions.

A potent, broadly protective vaccine against SARS-CoV-2 variants of concern.

Since the first outbreak in December 2019, SARS-CoV-2 has been constantly evolving and five variants have been classified as Variant of Concern (VOC) by the World Health Organization (WHO). These VOCs were found to enhance transmission and/or decrease neutralization capabilities of monoclonal antibodies and vaccine-induced antibodies. Here, we successfully designed and produced a recombinant COVID-19 vaccine in CHO cells at a high yield.

N4-acetylcytidine regulates the replication and pathogenicity of enterovirus 71.

Chemical modifications are important for RNA function and metabolism. N4-acetylcytidine (ac4C) is critical for the translation and stability of mRNA. Although ac4C is found in RNA viruses, the detailed mechanisms through which ac4C affects viral replication are unclear.

Efficacy of heterologous boosting against SARS-CoV-2 using a recombinant interferon-armed fusion protein vaccine (V-01): a randomized, double-blind and placebo-controlled phase III trial.

Waning of neutralizing titres along with decline of protection efficacy after the second dose of COVID-19 vaccines was observed, including China-made inactivated vaccines. Efficacy of a heterologous boosting using one dose of a recombinant SARS-CoV-2 fusion protein vaccine (V-01) in inactivated vaccine-primed population was studied, aimed to restore the immunity. A randomized, double-blind and placebo-controlled phase III trial was conducted in healthy people aged 18 years or older in Pakistan and Malaysia.

Nasal delivery of broadly neutralizing antibodies protects mice from lethal challenge with SARS-CoV-2 delta and omicron variants.

Multiple new variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have constantly emerged, as the delta and omicron variants, which have developed resistance to currently gained neutralizing antibodies. This highlights a critical need to discover new therapeutic agents to overcome the variants mutations. Despite the availability of vaccines against coronavirus disease 2019 (COVID-19), the use of broadly neutralizing antibodies has been considered as an alternative way for the prevention or treatment of SARS-CoV-2 variants infection.

Suppression and Activation of Intracellular Immune Response in Initial Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently the most important emerging pathogen worldwide, but its early transcriptional dynamics and host immune response remain unclear. Herein, the expression profiles of viral interactions with different types of hosts were comprehensively dissected to shed light on the early infection strategy of SARS-CoV-2 and the host immune response against infection. SARS-CoV-2 was found to exhibit a two-stage transcriptional strategy within the first 24 h of infection, comprising a lag phase that ends with the virus being paused and a log phase that starts when the viral load increases rapidly.

Transcriptomic characteristics and impaired immune function of patients who retest positive for SARS-CoV-2 RNA.

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, has become a global public health crisis. Some patients who have recovered from COVID-19 subsequently test positive again for SARS-CoV-2 RNA after discharge from hospital. How such retest-positive (RTP) patients become infected again is not known.

Chemiluminescence Immunoassay Based Serological Immunoassays for Detection of SARS-CoV-2 Neutralizing Antibodies in COVID-19 Convalescent Patients and Vaccinated Population.

The development of rapid serological detection methods re urgently needed for determination of neutralizing antibodies in sera. In this study, four rapid methods (ACE2-RBD inhibition assay, S1-IgG detection, RBD-IgG detection, and N-IgG detection) were established and evaluated based on chemiluminescence technology. For the first time, a broadly neutralizing antibody with high affinity was used as a standard for the quantitative detection of SARS-CoV-2 specific neutralizing antibodies in human sera.

Immunogenicity and safety of a recombinant fusion protein vaccine (V-01) against coronavirus disease 2019 in healthy adults: a randomized, double-blind, placebo-controlled, phase II trial.

Background: Innovative coronavirus disease 2019 (COVID-19) vaccines, with elevated global manufacturing capacity, enhanced safety and efficacy, simplified dosing regimens, and distribution that is less cold chain-dependent, are still global imperatives for tackling the ongoing pandemic. A previous phase I trial indicated that the recombinant COVID-19 vaccine (V-01), which contains a fusion protein (IFN-PADRE-RBD-Fc dimer) as its antigen, is safe and well tolerated, capable of inducing rapid and robust immune responses, and warranted further testing in additional clinical trials. Herein, we aimed to assess the immunogenicity and safety of V-01, providing rationales of appropriate dose regimen for further efficacy study.

Methyltransferase-like 3 Modulates Severe Acute Respiratory Syndrome Coronavirus-2 RNA N6-Methyladenosine Modification and Replication.

The coronavirus disease 2019 pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an ongoing global public crisis. Although viral RNA modification has been reported based on the transcriptome architecture, the types and functions of RNA modification are still unknown. In this study, we evaluated the roles of RNA N6-methyladenosine (mA) modification in SARS-CoV-2.

Antibody Cocktail Exhibits Broad Neutralization Activity Against SARS-CoV-2 and SARS-CoV-2 Variants.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has precipitated multiple variants resistant to therapeutic antibodies. In this study, 12 high-affinity antibodies were generated from convalescent donors in early outbreaks using immune antibody phage display libraries. Of them, two RBD-binding antibodies (F61 and H121) showed high-affinity neutralization against SARS-CoV-2, whereas three S2-target antibodies failed to neutralize SARS-CoV-2.

Safety and immunogenicity of a recombinant interferon-armed RBD dimer vaccine (V-01) for COVID-19 in healthy adults: a randomized, double-blind, placebo-controlled, Phase I trial.

Safe and effective vaccines are still urgently needed to cope with the ongoing COVID-19 pandemic. Recently, we developed a recombinant COVID-19 vaccine (V-01) containing fusion protein (IFN-PADRE-RBD-Fc dimer) as antigen verified to induce protective immunity against SARS-CoV-2 challenge in pre-clinical study, which supported progression to Phase I clinical trials in humans. A Randomized, double-blind, placebo-controlled Phase I clinical trial was initiated at the Guangdong Provincial Center for Disease Control and Prevention (Gaozhou, China) in February 2021.