Laboratory propagation of severe acute respiratory syndrome coronavirus 2 is essential for virological research, but adaptation in commonly used non-human cells with low transmembrane serine protease 2 expression may alter phenotypes relevant to biosafety and risk assessment. This study aimed to determine how serial passage in African green monkey-derived Vero E6 cells affects the growth, entry pathways, pathogenicity, and transmission of a clinical Delta strain. The parental virus was serially passaged to generate two adapted variants, which were characterized by whole-genome sequencing, replication and competition assays, spike cleavage and membrane fusion analyses, receptor binding studies, and animal experiments. The first variant acquired spike substitutions P217S, S247R, and H655Y, whereas the second acquired G261R and a six-amino-acid deletion immediately upstream of the furin cleavage site, plus non-spike mutations. Both variants replicated more efficiently than the parental virus in Vero E6, LLC-MK2, Huh-7, and HeLa cells expressing human angiotensin-converting enzyme 2 (ACE2), but not in Caco-2 cells. Their phenotypes reflected altered use of human transmembrane serine protease 2 rather than altered human ACE2 binding; they showed increased affinity for African green monkey ACE2 but unchanged affinity for the human receptor. Despite enhanced growth in vitro, both variants exhibited reduced pathogenicity and transmission in animals. These findings demonstrate that Vero E6 passage can rapidly reshape spike function and select viruses with improved cell-culture growth but impaired protease-dependent fitness in vivo, supporting rigorous genomic and phenotypic monitoring of laboratory-propagated virus stocks before use.
Influenza viruses cause annual seasonal epidemics and occasional pandemics. Vaccination is most effective at preventing influenza virus infections. Suspensions of the Madin-Darby canine kidney (MDCKs) cell line are used to manufacture cell-based influenza vaccines. In this study, we tested and optimized a range of culture conditions for a chimeric recombinant influenza virus rA/B-H3 in MDCK suspension cells, revealing that the optimal inoculation conditions were multiplicity of infection of 0.001, cell concentration of infection of 4.0 × 106 cells/mL, addition of 2 μg/mL of L-1-tosylamide-2-phenylethyl chloromethyl ketone, time of harvest of 72 h. The optimal parameter setting in a 5-L bioreactor was 50 % dissolved oxygen and pH 7.2 ± 0.05. The rA/B-H3 has stability genetic after 15 passages in MDCKs. The rA/B-H3 had several immune responsesin mice. Hemagglutination inhibition (HAI) antibodies, micro-neutralizing (MN) antibodies, and IgG antibodies were induced in immunized mice, and the mucosal IgA antibody responses were detected in their lung lavage fluids. The IFN-γ-secretion and IL-4-secretion by the mouse splenocytes were induced after stimulation with the specific H3N2 HA protein. Immunized mice resisted the lethal challenge with a wild-type H3N2 influenza virus. This study demonstrated the reliability of the MDCK suspension cell platform for the production of the chimeric H3N2 candidate vaccine, and the rA/B-H3 candidate vaccine is a potentially safe efficial vaccine.
IntroductionSevere Acute Respiratory Syndrome Coronavirus type 2 (SARS-CoV-2), a highly pathogenic coronavirus (CoV) belonging to Coronavirus B, has triggered outbreaks or pandemics. Currently, many variants of SARS-CoV-2 have evolved, which exhibit severe immune evasion and imprinting resistance to existing vaccines and cause infected individuals to develop Post-Acute Sequelae of SARS-CoV-2 (also termed Long-COVID). This underscores the public health importance of developing effective vaccines with broad-spectrum efficacy against the SARS-CoV-2 variant and other CoVs with pandemic potential.ResultsIn this study, we expressed three tandem-repeat dimeric recombinant RBD proteins using an insect-baculovirus expression system integrated with the high-frequency SARS-CoV-2 RBD mutation sites. We performed immunogenicity assessment and attack protection tests. The date showed that these innovative SARS-CoV-2 RBD recombinant protein vaccines could show varying degrees of cross-immunity response and potent protection against SARS-CoV-2.ConclusionOverall, our results indicated that these recombinant RBD subunit vaccines could serves a promising platform for a universal vaccine against SARS-CoV-2 and its variants, and provide a new perspective for the design of other future pandemic vaccines.
BackgroundThe fatality rate of virulent rabies virus (RABV) following central nervous system (CNS) invasion is nearly 100%. Infection with the virulent CVS-11 strain is associated with severe neurological symptoms and lethal outcomes, while the attenuated SRV9 strain can be cleared by the host. Although previous studies have investigated intracranial cytological and immunological changes, a high-resolution single-cell understanding is still lacking. Such resolution is essential for analyzing immune cell heterogeneity and intercellular communication networks.ObjectivesThis study aimed to depict the immune response after CVS-11 and SRV9 infections at single-cell resolution, addressing the immune mechanisms influencing RABV infection outcomes.MethodsWe performed single-cell RNA sequencing (scRNA-seq) on brains from CVS-11 infected, SRV9 infected, and mock infected mice. By analyzing over 100,000 cells, we constructed a comprehensive atlas of CNS immune responses.ResultCompared with SRV9 infection, CVS-11 infection was associated with transcriptional signatures indicative of: a trend of microglial shifting toward a phagocytic signature enriched phagocytic phenotype, elevated expression of genes related to excessive neutrophilic inflammation, down regulation of NK cell functional genes (suggesting potential dysfunction), and increased expression of T cell exhaustion-related genes. In contrast, SRV9 infection correlated with microglial features indicative of an immunoregulatory phenotype, more precise NK cell antiviral function, more complete T cell activation and memory formation, and more coordinated immune interactions.ConclusionThe scRNA-seq data from this study suggest that virulent and attenuated RABV strains may induce distinct patterns of immune responses in the central nervous system: the former is accompanied by features of dysfunctional cellular responses, whereas the latter presents protective immune features associated with viral clearance. Notably, a set of signature genes (Fkbp5, Apod, Klf2, Socs3) and pathways was identified associated with lethal RABV infection. These findings provide new insights for rabies vaccine design and immunotherapy.
Rabies remains a critical global health concern, particularly in endemic regions where timely access to postexposure prophylaxis (PEP) is often limited. The effectiveness of PEP relies heavily on rabies immune globulin (RIG), yet plasma-derived products continue to face persistent issues of limited supply, variable potency, and high cost. These constraints have intensified the demand for recombinant monoclonal antibodies (mAbs) that provide consistent quality and scalable production. Here, we describe the development of a fully human mAb, H81L90, directed against the rabies virus glycoprotein (RABV-G). The antibody was isolated from a phage-display library constructed using peripheral blood mononuclear cells (PBMCs) from vaccinated donors. H81L90 exhibited strong, specific binding to native RABV-G with nanomolar affinity as determined by surface plasmon resonance (SPR) analysis. In cell-based neutralization assays, H81L90 efficiently blocked infection by the ERA-enhanced green fluorescent protein (EGFP) strain, achieving complete viral inhibition at low microgram concentrations. Protective efficacy was subsequently evaluated in a murine challenge model, where a single intramuscular injection of H81L90 conferred full survival when administered before or at the time of viral exposure and retained measurable activity at reduced doses postexposure. Histopathological assessment revealed substantially lower viral antigen in hippocampal tissue from treated animals, indicating suppression of early neuroinvasion. Collectively, these data establish H81L90 as a potent, fully human antibody with both preventive and postexposure prophylactic potential, supporting its continued development as a next-generation biologic to complement or replace current RIG formulations in rabies PEP.
Feline panleukopenia virus (FPV) poses a significant threat to carnivores worldwide, with increasing documentation of spillover infections in endangered species, including the giant panda (Ailuropoda melanoleuca). Despite the presence of serological evidence indicating historical exposure, contemporary data concerning the prevalence of FPV and the associated risk factors in giant pandas remains limited. This study conducted a comprehensive seroepidemiological survey of 136 giant pandas, representing 262 serum samples, from the Chengdu Research Base of Giant Panda Breeding between 2015 and 2023. The overall seroprevalence of FPV antibodies was 56.87
Newly emerging influenza D virus (IDV), first identified in swine in 2011, has demonstrated broad mammalian tropism with notable prevalence in bovine populations and occupational exposure-associated seroprevalence among cattle workers. This zoonotic expansion raises concerns that IDV could acquire capability for human-to-human transmission via sustained evolving in mammal hosts. Here, we evaluated the infectivity and transmissibility of a currently circulating IDV strain, D/bovine/Jilin/HY11/2023 (abbreviated as D/HY11), isolated from cattle in Northeast China in 2023. D/HY11 was able to replicate efficiently in human primary respiratory epithelial cells and exhibits respiratory tract tropism in mammals. More importantly, we found that D/HY11 could efficiently transmit through the air between ferret models (5/6). Serological surveillance (2020-2024) revealed alarming exposure rates, with no significant difference in positivity between rural and urban populations: 73.37% (449/612) in the general population and an even higher rate of 96.67% (58/60) among individuals with respiratory symptoms. The extraordinary high IDV seropositivity among people in Northeast China highlights the possibility of silent spread in mammals with mild symptoms. Among generic anti-influenza drugs tested in vitro, only polymerase inhibitors demonstrated effective suppression of IDV replication. And the D/HY11 strain exhibited enhanced polymerase activity compared to the classical IDV strain, with preliminary evidence implicating the P3 gene as a potential contributing factor to this functional enhancement. Our pathogenetic and serological findings indicate that IDV may have acquired the capacity for human-to-human transmission during its ongoing evolution, and currently circulating IDV strains already pose a potential panzootic threat.
With the SARS-CoV-2 Omicron XBB.1.9 subvariants circulating worldwide, two XBB.1.9 variants, EG.5.1 and HK.3, spread rapidly and became dominant in mid-2023. However, the spike features, pathogenicity, and transmissibility of HK.3 are largely unknown. Here, we performed multiscale investigations to reveal the virological features of XBB.1.9 subvariants, including the newly emerging HK.3. HK.3 revealed high replication efficiency and enhanced TMPRSS2 utilization in vitro. The HK.3 spike exhibited enhanced processing, although its infectivity, fusogenicity, and human ACE2 (hACE2) binding affinity were comparable to those of the EG.5 and XBB.1 spikes. All XBB.1.9.1, EG.5.1, and HK.3 strains demonstrated efficient transmission in hamsters, although XBB.1.9.1 exhibited stronger fitness in the upper airways. XBB.1.9.1, EG.5.1, and HK.3 exhibited greater pathogenicity than BA.2 in H11-K18-hACE2 hamsters. Our studies provide insights into the newly emerging pathogens EG.5.1 and HK.3.IMPORTANCESARS-CoV-2 Omicron continues to circulate and evolve into novel lineages with indistinguishable pathogenicity and transmission. Ancestral Omicron lineages, such as BA.1 and BA.2, revealed attenuated pathogenicity and transmission, at least in animal models. However, on a previously reported Omicron-sensitive H11-K18-hACE2 hamster model, the infections of XBB.1.9 lineages, EG.5, and HK.3 led to faster lethality and more severe terminal bronchioles symptom than BA.2. They also revealed efficient transmission in a hamster model, which corresponds well with their prevalence in multiple countries. Our study highlights the importance of surveillance and virological studies on epidemic Omicron subvariants.
The emergence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) variants seriously threatens the efficacy of current coronavirus disease 2019 (COVID-19) vaccines. Therefore, there is an urgent need to develop next-generation vaccine platforms capable of counteracting current and prospective viral variants. In this study, we employed synthetic biology technology to develop self-adjuvant-effect biomimetic nanovaccines with broad-spectrum capabilities for the prevention of SARS-CoV-2 infection. The biomimetic nanovaccines prepared by loading the SARS-CoV-2 RBD protein into dendritic mesoporous organosilicon nanoparticles (DMOSN) significantly promote the recruitment of dendritic cells (DCs) to secondary lymphoid organs, thereby initiating antibody-dependent humoral immune responses mediated by follicle helper T (Tfh) cells, germinal center (GC) B cells, and plasma cells. Moreover, DMOSN@RBD induced not only potent humoral immunity but also Th2-biased cellular immunity along with robust Th1-type cellular immune responses, which are pivotal in restricting SARS-CoV-2 infection. Our work provides a simple and environmentally friendly strategy for synthesizing nanovaccines with significant immunostimulatory potential, offering novel insights for the future development of durable and effective antiviral broad-spectrum nanovaccines.IMPORTANCEThe persistent evolution of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) underscores the critical need to continually assess vaccine immunogenicity and protective efficacy against emerging variants in preclinical animal models. Our study demonstrates that biomimetic nanoparticle vaccines elicit more durable antibody responses and enhanced T cell responses compared to conventional aluminum hydroxide-adjuvanted formulations. Notably, RBD antigen-decorated dendritic mesoporous organosilica nanoparticles (DMOSN@RBD) exhibit broad-spectrum neutralization potential against multiple SARS-CoV-2 variants of concern (VOCs). These findings establish engineered mesoporous silica nanoparticles as a potent immunostimulatory platform capable of simultaneously enhancing both humoral and cellular immunity in subunit vaccine design, particularly through the induction of robust T cell responses typically challenging to achieve with protein-based vaccines.
Abstract Monkeypox virus (MPXV) is an important zoonotic pathogenic virus, which poses serious threats to public health. MPXV infection can be prevented by immunization against the variola virus. Because of the safety risks and side effects of vaccination with live vaccinia virus (VACV) strain Tian Tan (VTT), we constructed two gene-deleted VTT recombinants (TTVAC7 and TTVC5). The immunogenicity and protective effects of the gene-deleted VTT vaccine were assessed using BALB/C mice challenged with VTT and New Zealand rabbits challenged with MPXV. The results demonstrated strong humoral and cellular immune responses. The VTT-specific and neutralizing antibody titers, specific T cell levels, and degree of dendritic cell maturation of the mice, in addition to the MPXV neutralizing antibody titers and IFN-γ, IL-6, and TNF-α levels of the rabbits were markedly higher in the groups immunized with TTVAC7 and TTVC5 than the control groups (p < 0.05). Moreover, immunization with TTVAC7 and TTVC5 reduced morbidities caused by VACV and MPXV infection. The weight change, lung histological score, and residual virus of the mouse model (p < 0.05). Similarly, the temperature change, pock number, lung histological score, and residual virus of the rabbit model were significantly reduced in the groups immunized with TTVAC7 and TTVC5 (p < 0.05). Collectively, these results demonstrate that TTVAC7 and TTVC5 may be used as potential live attenuated vaccines against MPXV infection.
Influenza D virus (IDV) was first isolated from pigs in 2011 which caused the bovine respiratory disease and economic losses. This study aimed to develop an inactivated vaccine to protect against IDV using guinea pigs as an animal model. Vaccinated guinea pigs exhibited seroconversion with hemagglutination inhibition titers ranging from 1: 320 to 1: 640 and neutralizing antibody levels reaching 1: 2560 after booster immunity. In the vaccinated guinea pigs, viral titers were detected in the nasal lavage fluids from days one to seven, showing a significant difference from the control group. Peak viral shedding of approximately 106 TCID50/mL was measured in the nasal turbinate and nasal washes from days one to five. In contact transmission experiments, non-vaccinated guinea pigs that lived with the infection group were more likely to become infected than those in the vaccinated group. These results demonstrate that the inactivated IDV vaccine protected guinea pigs from contact transmission caused by homologous challenge. Our study provides a new choice for developing IDV vaccines to protect animals from IDV infections.
Canine distemper virus (CDV) is a multi-host pathogen with high morbidity and mortality, posing a severe threat to endangered carnivores, including giant pandas. Current vaccines carry risks of vaccine-induced disease in non-target species, creating an urgent need for safe and effective therapeutic alternatives. The hemagglutinin (H) protein is the primary antigen for stimulating neutralizing antibodies. In this study, we generated three murine monoclonal antibodies (mAbs)—2D1, 6G4, and 6H4—using the H protein from a giant panda-derived CDV strain expressed in a mammalian system to preserve authentic glycosylation and conformation. All three mAbs exhibited potent neutralizing activity against the giant panda-derived CDV strain in vitro. Western blot analysis revealed distinct epitope specificities: mAb 2D1 recognized a continuous epitope, as it bound to both eukaryotic and prokaryotically expressed H protein, whereas mAbs 6G4 and 6H4 only reacted with the eukaryotic-expressed protein, suggesting their recognition of non-continuous, conformational epitopes. These data indicate that these mAbs represent promising immunotherapeutic candidates for the control of CDV in giant pandas and other susceptible wildlife.
BACKGROUND:Pathogenic flaviviruses pose a serious threat to human health, and vaccines are an effective means of prevention and control. Although related vaccines have achieved significant progress, safety and efficacy limitations still exist, urgently requiring the development of novel vaccine platforms. The insect-specific flavivirus Chaoyang virus (CYV), with a structure similar to pathogenic flaviviruses and limited to insect cell replication, has potential as a safe vaccine vector. METHODS:To systematically evaluate CYV's potential as a universal flavivirus vaccine backbone and provide a vaccine candidate for type I Japanese encephalitis virus (JEV) prevention, this study constructed a chimeric JEV genotype I (GI) prME protein vaccine candidate CYV-JEV using CPER technology, systematically assessing its safety and immunoprotective effects. RESULTS:Using the CPER method, CYV-JEV was successfully rescued, showing efficient replication in mosquito cells but defective replication in mammalian cells. As a vaccine backbone, CYV did not induce inflammatory responses or immune cell subset imbalances in IFNAR-/- mice. CYV-JEV exhibited no pathogenicity in adult and suckling IFNAR-/- mice. Immunisation of IFNAR-/- mice with 106 FFU twice provided complete protection against lethal challenge (100%) and effectively reduced paralysis rates (62.5%). Single-cell sequencing further revealed extensive T- and B-cell activation in the immune spleen. CONCLUSIONS:The results demonstrate that the CYV-based CYV-JEV candidate vaccine demonstrates both safety and efficacy, representing a promising alternative to attenuated JEV vaccines, with CYV showing potential as a safe and effective universal flavivirus vaccine backbone.
COVID-19 and seasonal influenza have taken a huge toll on the global economy and global health. Given the potential of COVID-19 to transform into a chronic epidemic akin to seasonal influenza, the influenza virus and SARS-CoV-2 will continue to be a significant threat to healthcare for some time to come. Coinfection involving the two viruses has been proven to worsen the severity of the illness, as evidenced by clinical observational data. Vaccination remains the most effective measure in the prevention and treatment of infectious diseases. In addition, the coadministration of influenza virus and SARS-CoV-2 vaccines offered greater benefits than either vaccine alone. Combination vaccines are also a major hotspot in novel vaccine development. This review highlights the advancements in the development of combined vaccines for COVID-19 and seasonal influenza, as demonstrated in animal studies and clinical trials, and emphasizes the importance of a combined vaccine.
Mucosal vaccines are powerful tools for combatting emerging infectious diseases, particularly mucosal-associated pathogens. However, one of the main bottlenecks in developing mucosal vaccines is the lack of accurate animal models. In this study, a vesicular stomatitis virus (VSV)-vectored Middle East respiratory syndrome coronavirus (MERS-CoV) mucosal vaccine was designed for investigations. Compared with the VSV backbone, rVSVΔG-MERS-S exhibited altered cellular tropism, as determined by MERS-S. In wild-type (WT) C57BL-6J mice and hamsters, the nasal spray of rVSVΔG-MERS-S was poorly immunogenic. In contrast, rVSVΔG-MERS-S was highly immunogenic in transgenic mice (hDPP4 mice) and hDPP4-transduced hamsters harboring the functional MERS-CoV receptor. Compared with those of WT C57BL-6J mice, the nasal spray of rVSVΔG-MERS-S resulted in effective antigen-presenting cell (APC) priming, Tfh-GcB-plasma cell (pC) proliferation, and robust humoral and cellular responses, together with the activation of antiviral signaling pathways in hDPP4 mice. Similarly, rVSVΔG-MERS-S was highly immunogenic in alpacas and rhesus monkeys, which are naturally susceptible to MERS-CoV and harbor the effective DPP4 receptor. The alignment of hDPP4 receptors in these animals revealed that L294, I295, and R336 in DPP4 are key residues contributing to differences in sensitivity across species. Consistently, a high binding affinity was observed between human, alpacas, and rhesus monkey DPP4 receptors and MERS-CoV receptor binding domains (RBDs) compared with that of mice and hamster. Overall, this proof-of-concept study not only guides the selection of appropriate animal models for the evaluation of mucosal vaccines of MERS but also provides evidence that functional receptors DPP4 in animal models are prerequisites for the immune performance of the MERS mucosal vaccine.
Since its emergence at the end of 2023, the JN.1 variant of COVID-19 has become the dominant strain globally. Currently, its characteristics in related animal models remain largely unknown. The results indicate that JN.1 can cause weight loss, viral load, viral titer, and histopathological changes in golden hamsters via intranasal and intragastric inoculation methods, with intranasal inoculation leading to faster viral replication. Interestingly, both viral load and viral titer of JN.1 are significantly lower than those of its parental strains BA.2 and XBB EG.5.1. A comparison of hematological data from the two inoculation methods was also consistent with previous findings. This highlights the importance of the infection route in studying the virus's progression and characteristics. In direct transmission studies of JN.1, the minimum time for virus transmission was 24 h, while XBB EG.5.1 could transmit the virus in as little as 6 h. Finally, the in vivo adaptability of JN.1 was investigated, with XBB EG.5.1 showing a more apparent adaptability advantage. Therefore, compared with EG.5.1, the pathogenicity and transmissibility of JN.1 are significantly weakened.
The global eradication of canine-mediated human rabies remains an ongoing public health priority. While conventional oral rabies vaccines (ORVs) have demonstrated partial success in interrupting zoonotic transmission, current formulations necessitate improvements in both immunogenic profiles and mechanistic clarity. Herein, we present a recombinant vesicular stomatitis virus (VSV)-vectored vaccine candidate (rVSVΔG-ERA-G) engineered to express the glycoprotein of the rabies virus (RABV) ERA strain, substituting the native VSV glycoprotein. Preclinical evaluation across multiple mammalian species (Mus musculus, Canis lupus familiaris, Felis catus, Vulpes lagopus, and Nyctereutes procyonoides) revealed rapid seroconversion and sustained neutralizing antibody responses. Challenge experiments demonstrated 100% survival efficacy in pre-exposure prophylaxis models, with partial protection observed in post-exposure scenarios. Safety assessments confirmed significant attenuation of neurotropism and absence of horizontal transmission or environmental shedding. Furthermore, evidence showed that rVSVΔG-ERA-G is recognized by Peyer’s patches (PPs), where a cascade activation of immune cells occurred. From another perspective, the absence of functional microfold cells in PPs hampered the initiation and progression of immune responses. This proof-of-concept study establishes rVSVΔG-ERA-G as an ORV candidate with enhanced biosafety and cross-species immunogenicity. The elucidation of M cell-dependent mucosal priming mechanisms provides a rational framework for optimizing the targeted delivery of ORVs.
This study aims to explore the screening and mechanisms of action of traditional Chinese medicine(TCM) monomer compounds targeting transient receptor potential vanilloid 4(TRPV4) against severe acute respiratory syndrome coronavirus 2(SARS-CoV-2). Based on a machine learning method using the pre-trained protein language model ConPLex to predict drug-target binding properties, the study rapidly screened TRPV4-targeting TCM monomer compounds and ranked them by algorithm scores from highest to lowest. The cytotoxicity of candidate compounds was evaluated via cell counting kit-8(CCK-8), and the effects of glycycoumarin(GCM) on SARS-CoV-2 replication in African green monkey kidney cell line(Vero-E6) were analyzed through indirect immunofluorescence assay(IFA) and Western blot. A BALB/c mouse infection model with SARS-CoV-2/C57MA14 mouse-adapted strain was employed to assess the in vivo antiviral efficacy of GCM by examining the survival rate, pulmonary viral load, and pathological damage. To elucidate the molecular mechanism, Western blot was used to detect the protein expression of key signaling pathways, and enzyme-linked immunosorbent assay(ELISA) was applied to quantify concentrations of cytokines including interleu-kin-6(IL-6), tumor necrosis factor-alpha(TNF-α), C-X-C motif chemokine ligand 10(CXCL10), and monocyte chemoattractant protein-1(MCP-1) in serum. Molecular docking and molecular dynamics simulation techniques were employed to resolve the binding mode of GCM with the TRPV4 protein. In vitro experiments demonstrated that among 15 candidate compounds, GCM exhibited significant dose-dependent inhibition of SARS-CoV-2. In the animal model, the compound prolonged the survival time of infected mice and significantly alleviated virus-induced pulmonary pathological damage. Mechanistic studies revealed that GCM suppressed the TRPV4 expression, blocked nuclear translocation of nuclear factor kappa-B(NF-κB) triggered by SARS-CoV-2 infection, and subsequently downregulated the transcriptional level of pro-inflammatory factors such as IL-6 and TNF-α. Concurrently, the expression of IL-6, TNF-α, CXCL10, and MCP-1 in serum was markedly reduced after GCM intervention. The molecular docking and dynamics simulation confirmed that the GCM-TRPV4 compound exhibited excellent stability in both binding conformation and dynamic interactions. The study verified that GCM demonstrated potent anti-SARS-CoV-2 activity in both in vitro and in vivo models, effectively inhibiting viral replication while suppressing infection-induced cytokine storms. The results indicate that GCM is a highly promising anti-SARS-CoV-2 TCM monomer compound, which is worthy of further in-depth research and development.
Porcine epidemic diarrhea virus (PEDV) and transmissible gastroenteritis virus (TGEV) are causative agents of acute enteric diseases in pigs and have a high contagion potential. These coronaviruses (CoVs) impose substantial economic losses on global pork production, particularly affecting lactating piglets where coinfections occur. Although traditional vaccines offer partial protection, their efficacy is increasingly challenged by the continuous emergence of mutated strains of PEDV and TGEV. This underscores the demand for novel vaccines with improved protective efficacy and cost-effectiveness. Emerging vaccine technologies, such as nucleic acid vaccines, genetically engineered subunit vaccines, and live vector vaccines, have received widespread attention because of their advantages in terms of safety, stability, targeted delivery, economy, and ease of use. This review summarizes recent advances in PEDV and TGEV vaccine development, highlighting both their potential and limitations. More importantly, we prospect novel techniques that may supplement the status gaps and lead to breakthroughs in blocking the transmission of these CoVs. Notable research priorities encompass mucosal immunity mechanisms, vertical transmission prevention strategies, and computational immunogen design leveraging artificial intelligence (AI). Overall, a deeper understanding of the pathogens coupled with technological advances is expected to accelerate the control of and effective response to pathogenic CoVs, thereby safeguarding the stability of animal husbandry.