Viruses, Vol. 11, Pages 296: A Field Recombinant Strain Derived from Two Type 1 Porcine Reproductive and Respiratory Syndrome Virus (PRRSV-1) Modified Live Vaccines Shows Increased Viremia and Transmission in SPF Pigs

Viruses, Vol. 11, Pages 296: A Field Recombinant Strain Derived from Two Type 1 Porcine Reproductive and Respiratory Syndrome Virus (PRRSV-1) Modified Live Vaccines Shows Increased Viremia and Transmission in SPF Pigs Viruses doi: 10.3390/v11030296 Authors: Julie Eclercy Patricia Renson Arnaud Lebret Edouard Hirchaud Valérie Normand Mathieu Andraud Frédéric Paboeuf Yannick Blanchard Nicolas Rose Olivier Bourry In Europe, modified live vaccines (MLV) are commonly used to control porcine reproductive and respiratory syndrome virus (PRRSV) infection. However, they have been associated with safety issues such as reversion to virulence induced by mutation and/or recombination. On a French pig farm, we identified a field recombinant strain derived from two PRRSV-1 MLV (MLV1). As a result, we aimed to evaluate its clinical, virological, and transmission parameters in comparison with both parental strains. Three groups with six pigs in each were inoculated with either one of the two MLV1s or with the recombinant strain; six contact pigs were then added into each inoculated group. The animals were monitored daily for 35 days post-inoculation (dpi) for clinical symptoms; blood samples and nasal swabs were collected twice a week. PRRS viral load in inoculated pigs of recombinant group was higher in serum, nasal swabs, and tonsils in comparison with both vaccine groups. The first viremic contact pig was detected as soon as 2 dpi in the recom...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research

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Viruses, Vol. 13, Pages 1672: Characteristics of Classical Swine Fever Virus Variants Derived from Live Attenuated GPE− Vaccine Seed Viruses doi: 10.3390/v13081672 Authors: Taksoo Kim Loc Tan Huynh Shizuka Hirose Manabu Igarashi Takahiro Hiono Norikazu Isoda Yoshihiro Sakoda The GPE− strain is a live attenuated vaccine for classical swine fever (CSF) developed in Japan. In the context of increasing attention for the differentiating infected from vaccinated animals (DIVA) concept, the achievement of CSF eradication with the GPE− proposes it as a preferable backbone for a recombinant CSF...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research
In this study, we investigated the T-cell immune response in pigs that were vaccinated twice with Salmoporc followed by a challenge infection with a virulent STM strain. Blood- and organ-derived lymphocytes (spleen, tonsils, jejunal and ileocolic lymph nodes, jejunum, ileum) were stimulated in vitro with heat-inactivated STM. Subsequently, CD4+ T cells present in these cell preparations were analyzed for the production of IFN-γ, TNF-α, and IL-17A by flow cytometry and Boolean gating. Highest frequencies of STM-specific cytokine-producing CD4+ T cells were found in lamina propria lymphocytes of jejunum and ileum...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
AbstractPorcine reproductive and respiratory syndrome virus (PRRSV) infection is the most important viral disease causing severe economic losses in the swine industry. However, mechanisms underlying gene expression control in immunity-responsible tissues at different time points during PRRSV infection are poorly understood. We constructed an integrated gene co-expression network and identified tissue- and time-dependent biological mechanisms of PRRSV infection through bioinformatics analysis using three tissues (lungs, bronchial lymph nodes [BLNs], and tonsils) via RNA-Seq. Three groups with specific expression patterns (i...
Source: Veterinary Research - Category: Veterinary Research Source Type: research
Abstract Generation of antigen-specific humoral responses following vaccination or infection requires the maturation and function of highly specialized immune cells in secondary lymphoid organs (SLO), such as lymph nodes or tonsils. Factors that orchestrate the dynamics of these cells is still poorly understood. Nowadays, experimental approaches that enable for detailed description of the function of the immune system in SLO have been mostly developed and optimized in animal models. On the other hand, methodological approaches in humans are mainly based on the use of blood associated material because of the challe...
Source: Clinical and Developmental Immunology - Category: Allergy & Immunology Authors: Tags: Clin Exp Immunol Source Type: research
kh Belsham Rasmussen Vaccines against classical swine fever have proven very effective in protecting pigs from this deadly disease. However, little is known about how vaccination impacts the selective pressures acting on the classical swine fever virus (CSFV). Here we use high-throughput sequencing of viral genomes to investigate evolutionary changes in virus populations following the challenge of naïve and vaccinated pigs with the highly virulent CSFV strain “Koslov”. The challenge inoculum contained an ensemble of closely related viral sequences, with three major haplotypes being pr...
Source: Viruses - Category: Virology Authors: Tags: Article Source Type: research
Publication date: Available online 30 August 2019Source: Veterinary MicrobiologyAuthor(s): Wenjie Gong, Junhui Li, Zunbao Wang, Jiumeng Sun, Shijiang Mi, Jialun Xu, Jian Cao, Yuzhen Hou, Danyang Wang, Xinliang Huo, Yanjun Sun, Pengjiang Wang, Ke Yuan, Yangyi Gao, Xubin Zhou, Sun He, Changchun TuAbstractClassical swine fever (CSF) still threatens the swine industry in China, with genotype 2 isolates of CSFV dominating the epizootics. In 2018 the first E2 subunit marker vaccine against CSFV (Tian Wen Jing, TWJ-E2®), containing a baculovirus-expressed E2 glycoprotein of a genotype 1.1 vaccine strain, was officially licens...
Source: Veterinary Microbiology - Category: Veterinary Research Source Type: research
In this study, we compared the response of pigs vaccinated with the C strain to non-vaccinated pigs both challenged with a pathogenic strain of CSFV. Analysis of transcriptomic data from the tonsils of these animals during the early stages after vaccination and challenge reveals a set of regulated genes that appear throughout the analysis. Many of these are linked to the ISG15 antiviral pathway suggesting it plays a key role in the rapid and early protection conferred by C strain vaccination.
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
In conclusion, the mouse pharyngeal colonization model is an affordable and accessible experimental system that allows a broader group of research groups to test the importance of their findings in an in vivo model. There is a great deal of overlap between the bacterial and immune factors found to be important in human and murine pharyngeal colonization. Although MHC-II humanized mice could prove useful in answering certain questions, the use of inbred mouse lines appears to be sufficient for evaluation of most questions, both related to bacterial factors and the host immune response. However, when promising treatments or ...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
Sean P. Saunders1, Erica G. M. Ma1,2, Carlos J. Aranda1 and Maria A. Curotto de Lafaille1,3* 1Division of Pulmonary, Critical Care and Sleep Medicine, Laboratory of Allergy and Inflammation, Department of Medicine, New York University, New York, NY, United States 2Sackler Institute of Graduate Biomedical Sciences, New York University, New York, NY, United States 3Department of Cell Biology, New York University School of Medicine, New York, NY, United States The long-term effectiveness of antibody responses relies on the development of humoral immune memory. Humoral immunity is maintained by long-lived plasma ce...
Source: Frontiers in Immunology - Category: Allergy & Immunology Source Type: research
Jean-Philippe Auger, Anaïs-Christelle Boa, Mariela Segura and Marcelo Gottschalk* Research Group on Infectious Diseases in Production Animals (GREMIP) and Swine and Poultry Infectious Disease Research Center (CRIPA), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, QC, Canada Streptococcus suis is an important porcine bacterial pathogen and a zoonotic agent causing a variety of pathologies including sudden death, septic shock, and meningitis. Though serotype 2 is the most studied serotype due to its presence worldwide, serotype 9 is responsible for the greatest number of porcine cases...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
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