Search Results (124)

Stomata play a crucial role in plant immune responses, with their morphological characteristics closely linked to disease resistance. Accurate detection and analysis of stomatal phenotypic parameters are essential for soybean disease resistance research and variety breeding. However, traditional stoma detection methods are challenged by complex backgrounds and leaf vein structures in soybean images. To address these issues, we proposed a Soybean Stoma-YOLO (You Only Look Once) model (SS-YOLO) by incorporating large separable kernel attention (LSKA) in the Spatial Pyramid Pooling-Fast (SPPF) module of YOLOv8 and Deformable Large Kernel Attention (DLKA) in the Neck part. These architectural modifications enhanced YOLOV8′s ability to extract multi-scale and irregular stomatal features, thus improving detection accuracy. Experimental results showed that SS-YOLO achieved a detection accuracy of 98.7%. SS-YOLO can effectively extract the stomatal features (e.g., length, width, area, and orientation) and calculate related indices (e.g., density, area ratio, variance, and distribution). Across different soybean rust disease stages, the variety Dandou21 (DD21) exhibited less variation in length, width, area, and orientation compared with Fudou9 (FD9) and Huaixian5 (HX5). Furthermore, DD21 demonstrated greater uniformity in stomatal distribution (SEve: 1.02–1.08) and a stable stomatal area ratio (0.06–0.09). The analysis results indicate that DD21 maintained stable stomatal morphology with rust disease resistance. This study demonstrates that SS-YOLO significantly improved stoma detection and provided valuable insights into the relationship between stomatal characteristics and soybean disease resistance, offering a novel approach for breeding and plant disease resistance research. Full article

The unique ability of oncolytic viruses (OVs) to replicate in and destroy malignant cells while leaving healthy cells intact and activating the host immune response makes them powerful targeted anti-cancer therapeutic agents. Vesicular stomatitis virus (VSV) only causes mild and asymptomatic infection, lacks pre-existing immunity, can be genetically engineered for enhanced efficiency and improved safety, and has a broad cell tropism. VSV can facilitate targeted delivery of immunostimulatory cytokines for an enhanced immune response against cancer cells, thus decreasing the possible toxicity frequently observed as a result of systemic delivery. In this study, the oncolytic potency of the two rVSV versions, rVSV-dM51-GFP, delivering green fluorescent protein (GFP), and rVSV-dM51-mIL12-mGMCSF, delivering mouse interleukin-12 (mIL-12) and granulocyte-macrophage colony-stimulating factor (mGMCSF), was compared on the four murine cancer cell lines of different origin and healthy mesenchymal stem cells (MSCs) at 24 h post-infection by flow cytometry. Lewis lung carcinoma (LL/2) cells were demonstrated to be more susceptible to the lytic effects of both rVSV versions compared to melanoma (B16-F10) cells. Detection of expression levels of antiviral and pro-apoptotic genes in response to the rVSV-dM51-GFP infection by quantitative PCR (qPCR) showed lower levels of IFIT, RIG-I, and N-cadherin and higher levels of IFNβ and p53 in LL/2 cells. Subsequently, C57BL/6 mice, infused subcutaneously with the LL/2 cells, were injected intratumorally with the rVSV-dM51-mIL12-mGMCSF 7 days later to assess the synergistic effect of rVSV and immunostimulatory factors. The in vivo study demonstrated that treatment with two rVSV-dM51-mIL12-mGMCSF doses 3 days apart resulted in a tumor growth inhibition index (TGII) of over 50%. Full article

Background/Objectives: Leukemia is associated with high recurrence rates and cancer vaccines are emerging as a promising immunotherapy against the disease. Here, we investigate the mechanism of action by which a personalized vaccine made from leukemia cells infected with an oncolytic virus (ICV) induces anti-tumor immunity. Methods: Using the L1210 murine model, leukemia cells were infected and irradiated to create the ICV. The CRISPR-Cas9 system was used to engineer knockout cells to test in treatment efficacy studies. Results: We found that pro-inflammatory interferons (IFNs) that are produced by infected vaccine cells induce the immunoproteasome (ImP), a specialized proteasome subtype that is found in immune cells. Interestingly, we show that while a vaccine using the oncolytic vesicular stomatitis virus (oVSV) completely protects against tumor challenge, the wild-type (wt) virus, which does not induce the ImP, is not as effective. To delineate the contribution of the ImP for vaccine efficacy, we generated ImP-knockout cell lines and found no differences in treatment efficacy compared to wild-type cells. Furthermore, an ICV using another murine leukemia model that expresses the ImP only when infected by an IFN gamma-encoding variant of the virus demonstrated similar efficacy as the parental virus. Conclusions: Taken together, our data show that ImP expression by vaccine cells was not required for the efficacy of leukemia ICVs. Full article

Nipah virus (NiV) is a highly pathogenic bat-borne zoonotic pathogen that poses a significant threat to human and animal health, with fatality rates exceeding 70% in some outbreaks. Despite its significant public health impact, there are currently no licensed vaccines or specific therapeutics available. Various virological tools—such as reverse genetics systems, replicon particles, VSV-based pseudoviruses, and recombinant Cedar virus chimeras—have been widely used to study the molecular mechanisms of NiV and to support vaccine development. Building upon these platforms, we developed a replication-competent recombinant vesicular stomatitis virus (rVSVΔG-eGFP-NiV_BD F/G) expressing NiV attachment (G) and fusion (F) glycoproteins. This recombinant virus serves as a valuable tool for investigating NiV entry mechanisms, cellular tropism, and immunogenicity. The virus was generated by replacing the VSV G protein with NiV F/G through reverse genetics, and protein incorporation was confirmed via immunofluorescence and electron microscopy. In vitro, the virus exhibited robust replication, characteristic cell tropism, and high viral titers in multiple cell lines. Neutralization assays showed that monoclonal antibodies HENV-26 and HENV-32 effectively neutralized the recombinant virus. Furthermore, immunization of golden hamsters with inactivated rVSVΔG-eGFP-NiV_BD F/G induced potent neutralizing antibody responses, demonstrating its robust immunogenicity. These findings highlight rVSVΔG-eGFP-NiV_BD F/G as an effective platform for NiV research and vaccine development. Full article

Recombinant vesicular stomatitis virus (rVSV) is a promising viral vaccine vector for addressing the COVID-19 pandemic. Inducing mucosal immunity via the intranasal route is an ideal strategy for rVSV-based vaccines, but it requires extremely stringent safety standards. In this study, we constructed two rVSV variants with amino acid mutations in their M protein: rVSV-M2 with M33A/M51R mutations and rVSV-M4 with M33A/M51R/V221F/S226R mutations, and developed COVID-19 vaccines based on these attenuated vectors. By comparing viral replication capacity, intranasal immunization, intracranial injection, and blood cell counts, we demonstrated that the M protein mutation variants exhibit significant attenuation effects both in vitro and in vivo. Moreover, preliminary investigations into the mechanisms of virus attenuation revealed that these attenuated viruses can induce a stronger type I interferon response while reducing inflammation compared to the wild-type rVSV. We developed three candidate vaccines against SARS-CoV-2 using the wildtype VSV backbone with either wild-type M (rVSV-JN.1) and two M mutant variants (rVSV-M2-JN.1 and rVSV-M4-JN.1). Our results confirmed that rVSV-M2-JN.1 and rVSV-M4-JN.1 retain strong immunogenicity while enhancing safety in hamsters. In summary, the rVSV variants with M protein mutations represent promising candidate vectors for mucosal vaccines and warrant further investigation. Full article

Nitric oxide and reactive nitrogen species are key signalling molecules with pleiotropic effects in plants. They are crucial elements of the redox regulation of plant stress responses to abiotic and biotic stresses. Nitric oxide is known to enhance photosynthetic efficiency under abiotic stress, and reactive nitrogen species-mediated alterations in photosynthetic metabolism have been shown to confer resistance to abiotic stresses. However, knowledge about the role of reactive nitrogen species in plant immune responses remains limited. In this review, we highlight recent advancements in understanding the role of NO in regulating stomatal movement, which contributes to resistance against pathogens. We will examine the involvement of NO in the regulation of photosynthesis, which provides energy, reducing equivalents and carbon skeletons for defence, as well as the significance of protein S-nitrosylation in relation to immune responses. The role of NO synthesis induced in pathogenic organisms during plant–pathogen interactions, along with S-nitrosylation of pathogen effectors to counteract their pathogenesis-promoting activity, is also reported. We will discuss the progress in understanding the interactions between reactive nitrogen species and photosynthetic metabolism, focusing on enhancing crop plants’ productivity and resistance in challenging environmental conditions. Full article

Tonsils are secondary lymphoid organs that play a crucial role in the immunological response, with B cells being a major component involved in both innate and adaptive immunity. Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome and obstructive sleep apnea syndrome (OSAS) are both common pediatric conditions involving tonsillar pathology. In both syndromes, the molecular pathways dysregulated in tonsillar B cells are still to be understood. The study aimed to unravel and compare the proteomic profiles of tonsillar CD19+ B cells isolated from pediatric patients with PFAPA (n = 6) and OSAS (n = 6) to identify disease-specific molecular signatures. B cells were isolated from the tonsillar tissue using magnetic microbeads (with a purity of 93.50%). Proteomic analysis was performed by nanoLC-MS/MS with both data-dependent (DDA) and data-independent acquisition (DIA) methods, followed by comprehensive bioinformatic analysis. By merging DDA and DIA datasets, a total of 18.078 unique proteins were identified. Differential expression analysis revealed 83 proteins increased and 49 proteins decreased in OSAS B cells compared to PFAPA B cells (fold change ≥ 1.5 or ≤0.6, p < 0.05). Distinct pathway enrichments were highlighted, including alterations in the regulation of PTEN gene transcription, circadian gene expression, inflammasome pathways (IPAF and AIM2), and the metabolism of angiotensinogen to angiotensin. Specific proteins such as p53, Hdac3, RPTOR, MED1, Caspase-1, Cathepsin D, Chymase, and TLR2 (validated by WB) were shown to be differentially expressed. These findings reveal distinct proteomic signatures in tonsillar B cells from patients with PFAPA and OSAS, offering novel insights into the pathophysiology and potential avenues for biomarker discovery. Full article

Background/Objectives: CD47 is a cell surface glycoprotein moderately expressed in healthy cells and upregulated in cancer and viral infected cells. CD47’s interaction with signal regulatory protein alpha (SIRPα) inhibits phagocytic cells and its interaction with thrombospondin-1 inhibits T cell response. Experimental evidence has revealed that the blockade of CD47 resulted in the increased activation and function of both innate and adaptive immune cells, therefore exerting antitumoral and antiviral effects. Recent studies have shown that the combination of vaccines and immune checkpoint inhibitors could be a promising approach to increasing vaccine immunogenicity. Here, we investigated the vaccinal effect of anti-CD47 antibodies and discussed the possibilities of combining anti-CD47 treatments with vaccines. Methods: Using vesicular stomatitis virus (VSV), a widely used replication-competent vaccine vector, we evaluated the impact of the immunotherapeutic blockade of CD47 on cellular, humoral, and protective immunity. We infected C57BL/6 mice with VSV, treated them with anti-CD47 antibodies or an isotype, and evaluated the total immunoglobulin (Ig), IgG neutralizing antibodies, B cell activation, CD8+ T cell effector function, and survival of the mice. Results: We found that the treatments of anti-CD47 antibodies led to significantly increased Ig and IgG neutralizing antibody levels compared to the isotype treatment. Flow cytometric analysis of B cells revealed no difference in the number of circulating B cells; however, we observed an increased surface expression of CD80 and CD86 in B cells among anti-CD47-treated mice. Further analysis of the impact of CD47 blockade on T immunity revealed a significantly higher percentage of IFN-γ⁺ CD4 and IFN-γ⁺ CD8 T cells in anti-CD47-treated mice. Upon infecting mice with a lethal VSV dose, we observed a significantly higher survival rate among the anti-CD47-treated mice compared to control mice. Conclusions: Our results indicate that anti-CD47 treatment induces a stronger cellular and humoral immune response, leading to better protection. As such, immunotherapy by CD47 blockade in combination with vaccines could be a promising approach to improve vaccine efficacy. Full article

This review provides an updated overview of oncolytic virotherapy as a promising therapeutic strategy for colorectal cancer (CRC), focusing on six key viral platforms: adenovirus, herpes simplex virus (HSV), reovirus, vesicular stomatitis virus (VSV), vaccinia virus (VV), and measles virus (MV). These viruses exhibit tumor-selective replication and exert their effects through mechanisms such as direct oncolysis, the delivery of immunostimulatory genes (e.g., IL-12, IL-15, GM-CSF), the activation of innate and adaptive immune responses, and the remodeling of the tumor microenvironment. Preclinical and early clinical studies suggest that oncolytic viruses can enhance the efficacy of existing treatments, particularly in immunologically “cold” tumors such as microsatellite stable CRC, when used in combination with chemotherapy or immune checkpoint inhibitors. Despite encouraging results, several challenges remain, including antiviral immune clearance, tumor heterogeneity, and limitations in systemic delivery. Current research focuses on improving viral engineering, enhancing tumor targeting, and designing combinatorial strategies to overcome resistance and maximize clinical benefits. Overall, oncolytic viruses represent a versatile and evolving therapeutic class with the potential to address unmet clinical needs in CRC. Full article

Streptomyces vinaceus strain SVFJ-07 is a biocontrol bacterium employed to control anthracnose disease caused by Colletotrichum gloeosporioides in Chinese orchids. This study investigated the mechanism of strain SVFJ-07-induced stomatal immunity-related closure in preventing the infection of anthracnose disease. After the foliar application of strain SVFJ-07, we analyzed the differential patterns of stomatal opening in Chinese orchids and measured the hormone levels of abscisic acid (ABA) and salicylic acid (SA). RNA sequencing (RNA-seq) was utilized to examine the differential expression of genes involved in SA and ABA signal transduction and disease resistance genes, which were induced by strain SVFJ-07. The results demonstrated that strain SVFJ-07 inhibited the infection of pathogens by inducing stomatal closure. Compared with the control group, the foliar application of strain SVFJ-07 significantly reduced stomatal length, width, and aperture. Furthermore, orchid plants treated with strain SVFJ-07 and infected with C. gloeosporioides exhibited elevated levels of endogenous ABA and SA, indicating that strain SVFJ-07 enhanced stomatal immunity and disease resistance in these plants. The transcriptome analysis revealed the upregulation of genes associated with stomatal immunity, particularly those involved in plant–pathogen interactions, peroxisome metabolism, plant hormone signaling, and mitogen-activated protein kinase (MAPK) signaling pathways. These findings confirmed that the induction of SVFJ-07 promoted stomatal closure to resist the infection of C. gloeosporioides and induced complex transcriptome-wide changes. Further investigation of the differentially expressed genes enhanced our understanding of the resistance mechanisms induced by S. vinaceus strain SVFJ-07. Full article

Hantaviruses, including the Sin Nombre virus (SNV) and Andes virus (ANDV), are associated with severe global health risks, causing high mortality rates in hantavirus pulmonary syndrome (HPS) patients. Neutralizing antibodies are essential for virus clearance and survival, making neutralization assays critical for understanding immunity and evaluating therapeutic strategies. In this study, we developed a recombinant vesicular stomatitis virus (VSV)-based surrogate system expressing SNV and ANDV glycoproteins (GPCs), enabling neutralization studies under biosafety level 2 conditions. The neutralization titers obtained with the VSV-based system closely matched the findings from authentic hantavirus assays performed under biosafety level 3 conditions, confirming its potential as a useful tool for determining immune responses and advancing hantavirus research. Full article

Over the past several decades, viral vector-based vaccines have emerged as some of the most versatile and potent platforms in modern vaccinology. Their capacity to deliver genetic material encoding target antigens directly into host cells enables strong cellular and humoral immune responses, often superior to what traditional inactivated or subunit vaccines can achieve. This has accelerated their application to a wide array of pathogens and disease targets, from well-established threats like HIV and malaria to emerging infections such as Ebola, Zika, and SARS-CoV-2. The COVID-19 pandemic further highlighted the agility of viral vector platforms, with several adenovirus-based vaccines quickly authorized and deployed on a global scale. Despite these advances, significant challenges remain. One major hurdle is pre-existing immunity against commonly used vector backbones, which can blunt vaccine immunogenicity. Rare but serious adverse events, including vector-associated inflammatory responses and conditions like vaccine-induced immune thrombotic thrombocytopenia (VITT), have raised important safety considerations. Additionally, scaling up manufacturing, ensuring consistency in large-scale production, meeting rigorous regulatory standards, and maintaining equitable global access to these vaccines present profound logistical and ethical dilemmas. In response to these challenges, the field is evolving rapidly. Sophisticated engineering strategies, such as integrase-defective lentiviral vectors, insect-specific flaviviruses, chimeric capsids to evade neutralizing antibodies, and plug-and-play self-amplifying RNA approaches, seek to bolster safety, enhance immunogenicity, circumvent pre-existing immunity, and streamline production. Lessons learned from the COVID-19 pandemic and prior outbreaks are guiding the development of platform-based approaches designed for rapid deployment during future public health emergencies. This review provides an exhaustive, in-depth examination of the historical evolution, immunobiological principles, current platforms, manufacturing complexities, regulatory frameworks, known safety issues, and future directions for viral vector-based vaccines. Full article

The recombinant vesicular stomatitis virus-Zaire Ebolavirus envelope glycoprotein vaccine (rVSVΔG-ZEBOV-GP) was highly effective against Ebola virus disease in a ring vaccination trial conducted during the 2014–2016 outbreak in Guinea and is licensed by regulatory agencies including US FDA, EMA, and prequalified by WHO. Vaccination studies in a nonhuman primate (NHP) model guided initial dose selection for clinical trial evaluation. We summarize two dose-ranging studies with the clinical-grade rVSVΔG-ZEBOV-GP vaccine candidate to assess the impact of dose level on immune responses and efficacy in an NHP Ebola virus (EBOV) challenge model. Forty-six cynomolgus macaques were vaccinated with a wide range of rVSVΔG-ZEBOV-GP doses and challenged 42 days later intramuscularly with 1000 pfu EBOV. Vaccination with rVSVΔG-ZEBOV-GP induced relatively high levels of EBOV-specific IgG and neutralizing antibodies, measured using the same validated assays as used in rVSVΔG-ZEBOV-GP clinical trials. Similar responses were observed across dose groups from 1 × 10⁸ to 1 × 10² pfu. A single vaccination conferred 98% protection from lethal intramuscular EBOV challenge across all dose groups. These results demonstrate that robust antibody titers are induced in NHPs across a wide range of rVSVΔG-ZEBOV-GP vaccine doses, correlating with high levels of protection against death from EBOV challenge. Full article

Background: Porcine epidemic diarrhea virus (PEDV) is a significant pathogen in swine, causing substantial economic losses worldwide. Despite the availability of existing vaccines, there is a critical need for novel vaccine platforms that ensure robust protection while maintaining safety. Methods: A recombinant replication-deficient vesicular stomatitis virus (VSV) vaccine, rVSV∆G-PEDV-S, was developed by pseudotyping the virus with the spike (S) protein from PEDV. To achieve high-titer pseudotyped rVSV particles, a stable Huh7 cell line expressing the PEDV S protein (Huh7-PEDV-S) was generated. The infectivity and replication capacity of rVSV∆G-PEDV-S were evaluated in PEDV-susceptible cell lines and Huh7-PEDV-S cells. The vaccine’s immunogenicity and safety were assessed in BALB/c mice vaccinated intramuscularly with rVSV∆G-PEDV-S. Results: The pseudotyped rVSV∆G-PEDV-S demonstrated infectivity in PEDV-susceptible cell lines and robust replication in Huh7-PEDV-S cells, while remaining replication-deficient in non-complementary cells. In vaccinated BALB/c mice, the vaccine elicited a strong humoral immune response, characterized by high levels of PEDV S1-specific IgG and neutralizing antibodies. No adverse effects, including weight loss or behavioral changes, were observed in the vaccinated mice, confirming the vaccine’s safety. Conclusions: The rVSV∆G-PEDV-S vaccine represents a promising platform for controlling PEDV outbreaks. Its replication-deficient design and pseudotyping methodology ensure safety and adaptability to emerging PEDV variants. These findings highlight the potential of rVSV∆G-PEDV-S as a safe and effective solution to the ongoing challenges posed by PEDV. Full article

The vesicular stomatitis virus (VSV)-vectored African swine fever virus (ASFV) vaccine can induce efficient immune response, but the potential mechanism remains unsolved. In order to investigate the efficacy of recombinant viruses (VSV-p35, VSV-p72)-mediated dendritic cells (DCs) maturation and the mechanism of inducing T-cell immune response, the functional effects of recombinant viruses on DC activation and target antigens presentation were explored in this study. The results showed that surface-marked molecules (CD80, CD86, CD40, and MHC-II) and secreted cytokines (IL-4, TNF-α, IFN-γ) were highly expressed in the recombinant virus-infected DCs. In addition, the co-culture results of recombinant virus-treated DCs with naive T cells showed that the Th1- and Th17-type responses were effectively activated. Taken together, the study indicated that the VSV-vectored ASFV vaccine activated the maturation of DCs and the Th1- and Th17-type immune response, which provided a theoretical basis for the development of novel ASF vaccines. Full article