24 research outputs found
Association between nasal shedding and fever that influenza A (H3N2) induces in dogs
<p>Abstract</p> <p>Background</p> <p>Avian origin canine influenza virus was reported in Korea. The dog to dog contact transmission of the avian origin canine influenza virus (CIV) H3N2 and CIV H3N8 was shown by experimental contact transmission. This study was focused on viral excretion and fever in order to elucidate the epidemiological associations which might be helpful to control the disease transmissions in CIV outbreak in dogs.</p> <p>Methods</p> <p>An influenza seronegative 10-week-old Beagle dog was experimentally inoculated with the canine influenza virus A/canine/01/2007, subtype H3N2. Eight hours after inoculation, the infected dog was cohoused with seven uninfected Beagle dogs. Clinical signs including fever were recorded for 14 days post inoculation.</p> <p>Results</p> <p>The infected dog and four of seven contact dogs in the study showed clinical signs (sneezing, nasal discharge and coughing) during the study. Viral shedding occurred in all of the animals tested and began on 1 to 6 DPI in dogs with clinical signs. Elevated body temperatures above 39.5°C (geometric mean temperature of 39.86°C±0.49) were observed in all symptomatic dogs. The mean viral titer during fever was 2.99 log EID<sub>50</sub>/ml, which was significantly higher than the viral titer detected in the non fever.</p> <p>Conclusions</p> <p>The data show that contact dogs with a canine influenza infected dog shed different levels of virus in their nasal excretions and demonstrate that clinical signs, including fever, significantly correlate with the viral shedding.</p
Development of a neutralization monoclonal antibody with a broad neutralizing effect against SARS-CoV-2 variants
Background
The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants has challenged the effectiveness of current therapeutic regimens. Here, we aimed to develop a potent SARS-CoV-2 antibody with broad neutralizing effect by screening a scFv library with the spike protein receptor-binding domain (RBD) via phage display.
Methods
SKAI-DS84 was identified through phage display, and we performed pseudovirus neutralization assays, authentic virus neutralization assays, and in vivo neutralization efficacy evaluations. Furthermore, surface plasmon resonance (SPR) analysis was conducted to assess the physical characteristics of the antibody, including binding kinetics and measure its affinity for variant RBDs.
Results
The selected clones were converted to human IgG, and among them, SKAI-DS84 was selected for further analyses based on its binding affinity with the variant RBDs. Using pseudoviruses, we confirmed that SKAI-DS84 was strongly neutralizing against wild-type, B.1.617.2, B.1.1.529, and subvariants of SARS-CoV-2. We also tested the neutralizing effect of SKAI-DS84 on authentic viruses, in vivo and observed a reduction in viral replication and improved lung pathology. We performed binding and epitope mapping experiments to understand the mechanisms underlying neutralization and identified quaternary epitopes formed by the interaction between RBDs as the target of SKAI-DS84.
Conclusions
We identified, produced, and tested the neutralizing effect of SKAI-DS84 antibody. Our results highlight that SKAI-DS84 could be a potential neutralizing antibody against SARS-CoV-2 and its variants.This work was supported by the National Research Foundation of Korea (NRF-2021R1F1A1055906, NRF-2014M3A9D5A01075128, 2021M3H9A1030260) grant funded by the Korea government (MSIT). This research was supported by the R&D Project for the Improvement of Science and Industrial Technology in Gwangwon-do (2022-DD-UP-0287
Laboratory information management system for COVID-19 non-clinical efficacy trial data
Background : As the number of large-scale studies involving multiple organizations producing data has steadily increased, an integrated system for a common interoperable format is needed. In response to the coronavirus disease 2019 (COVID-19) pandemic, a number of global efforts are underway to develop vaccines and therapeutics. We are therefore observing an explosion in the proliferation of COVID-19 data, and interoperability is highly requested in multiple institutions participating simultaneously in COVID-19 pandemic research.
Results : In this study, a laboratory information management system (LIMS) approach has been adopted to systemically manage various COVID-19 non-clinical trial data, including mortality, clinical signs, body weight, body temperature, organ weights, viral titer (viral replication and viral RNA), and multiorgan histopathology, from multiple institutions based on a web interface. The main aim of the implemented system is to integrate, standardize, and organize data collected from laboratories in multiple institutes for COVID-19 non-clinical efficacy testings. Six animal biosafety level 3 institutions proved the feasibility of our system. Substantial benefits were shown by maximizing collaborative high-quality non-clinical research.
Conclusions : This LIMS platform can be used for future outbreaks, leading to accelerated medical product development through the systematic management of extensive data from non-clinical animal studies.This research was supported by the National research foundation of Korea(NRF) grant funded by the Korea government(MSIT) (2020M3A9I2109027 and 2021M3H9A1030260)
Characteristics and Pathogenicity of the Cell-Adapted Attenuated Porcine Epidemic Diarrhea Virus of the Non-S INDEL Cluster
The high antigenic diversity of porcine epidemic diarrhea virus (PEDV) means that porcine epidemic diarrhea (PED) is a challenge for the global pig industry. Understanding the circulation of the virus to determine an optimal vaccine strategy is important in controlling the disease. In this study, we describe the genetic diversity of circulating PEDV based on the full sequences of spike genes of eight positive samples collected in Vietnam since 2018. Additionally, we developed a live attenuated vaccine candidate from the cell-adapted PEDV2 strain, which was continuously passaged until level 103 in VERO-CCL81 cells. PEDV2-p103, which belongs to the emerging non-S INDEL cluster, exhibited low virus shedding, did not induce lesions in the small intestine of challenged piglets, and had a high titer in the VERO-CCL81 cell at 48 h post-infection. These results suggest that the PEDV2-p103 strain could be a potential oral attenuated vaccine, and its immunogenicity and efficacy should be further assessed through in vivo tests
Cell-mimetic biosensors to detect avian influenza virus via viral fusion
Avian influenza virus (AIV) causes acute infectious diseases in poultry, critically impacting food supply. Highly pathogenic avian influenza viruses (HPAIVs), in particular, cause morbidity and mortality, resulting in significant economic losses in the poultry industry. To prevent the spread of HPAIVs, detection at early stages is critical to implement effective countermeasures such as quarantine and isolation. Through a viral fusion mechanism, cell-mimetic nanoparticles (CMPs), developed in the current study, can rapidly detect HPAIV and low pathogenic AIV (LPAIV). The CMPs comprise polymeric nanoparticles, which are constructed using sialic acid and fluorescence resonance energy transfer (FRET) dye pairs that expose the FRET off signal in response to LPAIV and HPAIV, after activation by enzymatic cleavage in the endosomal environment. The CMPs detect a wide variety of LPAIVs and HPAIVs in biological environments. Additionally, the cross-reactivity of CMPs is determined by testing their function with different viral species. Therefore, these findings demonstrate the significant potential of the proposed strategy for mimicking viral infection in vitro and using them as a highly effective diagnostic assay to rapidly detect LPAIV and HPAIV, preventing economic losses associated with viral outbreaks.N
Susceptibility to SARS-CoV-2 and MERS-CoV in Beagle Dogs
The coronavirus disease 19 (COVID-19) pandemic, caused by the severe acute respiratory syndrome, coronavirus 2 (SARS-CoV-2), has resulted in unprecedented challenges to healthcare worldwide. In particular, the anthroponotic transmission of human coronaviruses has become a common concern among pet owners. Here, we experimentally inoculated beagle dogs with SARS-CoV-2 or Middle East respiratory syndrome (MERS-CoV) to compare their susceptibility to and the pathogenicity of these viruses. The dogs in this study exhibited weight loss and increased body temperatures and shed the viruses in their nasal secretions, feces, and urine. Pathologic changes were observed in the lungs of the dogs inoculated with SARS-CoV-2 or MERS-CoV. Additionally, clinical characteristics of SARS-CoV-2, such as increased lactate dehydrogenase levels, were identified in the current study
Advanced Strategies for Developing Vaccines and Diagnostic Tools for African Swine Fever
African swine fever (ASF) is one of the most lethal infectious diseases affecting domestic pigs and wild boars of all ages. Over a span of 100 years, ASF has continued to spread over continents and adversely affects the global pig industry. To date, no vaccine or treatment has been approved. The complex genome structure and diverse variants facilitate the immune evasion of the ASF virus (ASFV). Recently, advanced technologies have been used to design various potential vaccine candidates and effective diagnostic tools. This review updates vaccine platforms that are currently being used worldwide, with a focus on genetically modified live attenuated vaccines, including an understanding of their potential efficacy and limitations of safety and stability. Furthermore, advanced ASFV detection technologies are presented that discuss and incorporate the challenges that remain to be addressed for conventional detection methods. We also highlight a nano-bio-based system that enhances sensitivity and specificity. A combination of prophylactic vaccines and point-of-care diagnostics can help effectively control the spread of ASFV