46 research outputs found
Molecular characteristics of a novel recombinant of porcine epidemic diarrhea virus.
Porcine epidemic diarrhea (PED) is a contagious viral disease in pigs, caused by the coronavirus porcine epidemic diarrhea virus (PEDV). PEDV infection results in significant mortality in piglets in unvaccinated herds. Like many others RNA viruses, PEDV has high evolutionary rate and is prone to genetic mutations. In this study, we analyzed the complete genome sequence of the recently sequenced isolate PEDV/Belgorod/dom/2008. A recombination event in S gene of PEDV/Belgorod/dom/2008 was detected. Pairwise identity analysis of the whole genome sequences revealed that PEDV/Belgorod/dom/2008 is an intermediate between PEDV and transmissible gastroenteritis virus (TGEV) strains. These results can be used for further analysis of the evolutionary variability, prevalence, and epidemiology of the porcine epidemic diarrhea virus
RESULTS OF Fc-PROTEIN FUSION TECHNOLOGY APPLICATION FOR VACCINE DESIGN AGAINST INFECTIOUS DISEASES OF ANIMALS AND HUMAN
The main criteria for current vaccines design are effectiveness, efficaciousness and safety. Increasing requirements for vaccine safety and purity push forward not only classical vaccine development, but also new generation vaccine technology, including sub-unit, recombinant, anti-idiotypic, DNA vaccines etc. This recombinant technology has already demonstrated its advantage, efficaciousness and safety in a large field of therapeutic and curative drug development for animal and human (S. Khan et al., 2016). In 2011, six novel drugs were created based on the new Fc-fusion protein technology. Most of the newly developed drugs affect receptor-ligand interactions, acting as antagonists by blocking direct receptor binding, i.e. Enbrel (etanercept; Amgen, USA), Zaltrap (aflibercept; Sanofi, France), Arcalyst (rilonacept; Regeneron, USA), or as agonists for direct stimulation of receptor function which augment immune response as Amevive (alefacept, Astellas, USA) does, or decrease immune response as Nplate (romiplostim; Amgen, USA) does. In this review, we pay attention to the most relevant results from the last few years for virus and bacterial vaccine designed based on Fc-fusion technology. The Fc-chimeras are hybrid sequences in which Fc-fragment of IgG (Fc-IgG) and targeted therapeutic protein are fused in an entire protein molecule (V. Pechtner et al., 2017). In this fusion, the hinge region of Fc-IgG is a flexible spacer between therapeutic protein and conservative part of IgG. It helps to minimize potential negative effect of two functional domains to each other. Therapeutic drugs based on Fc-fusion proteins are divided in three types, the receptor-Fc, peptide-Fc, and monomer-Fc. The Fc-fused proteins have tremendous therapeutic potential, since Fc domain in this molecules helps to specifically augment the pharmaco-dynamics values. Presence of Fc-domain in hybrid molecules prolongs half elimination of protein from plasma, which extends drug therapeutic activity and slows down kidney clearance for large molecules. Here, we summarize the most significant experimental data of Fc-fusion technology application against such pathogens as human immunodeficiency virus (D. Capon et al., 1989), Ebola virus (K. Konduru et al., 2011), Dengue virus (M.Y. Kim et al., 2018), influenza virus (L. Du et al., 2011), Mycobacterium tuberculosis (S. Soleimanpour et al., 2015), classical swine fever virus (Z. Liu et al., 2017). We also discuss the critical aspects of mechanism of action, drug design and Fc-fused protein production. Targeted activation of effector systems boosts protective potential of immuno-genic molecules and broadens its application. The interest of this review is focused on an application of Fc-fused proteins as potential vaccines against infectious human and animal diseases. We also briefly discuss the perspectives of Fc-fused antigens for novel effective medicine developments using African swine fever virus as an example
Complete Genome Sequence of a Porcine Epidemic Diarrhea Virus Isolated in Belgorod, Russia, in 2008.
We identified porcine epidemic diarrhea virus (PEDV) in stool samples from sick piglets in the Belgorod region of Russia. The complete coding genome sequence of 28,295 nucleotides (nt) of PEDV was generated. Compared to a prototype PEDV strain (DR13), an extreme number of mismatches in the S gene were revealed
Estimating the Basic Reproductive Number for African Swine Fever Using the Ukrainian Historical Epidemic of 1977
African Swine Fever Virus, Siberia, Russia, 2017.
African swine fever (ASF) is arguably the most dangerous and emerging swine disease worldwide. ASF is a serious problem for the swine industry. The first case of ASF in Russia was reported in 2007. We report an outbreak of ASF in Siberia, Russia, in 2017
Survival of African Swine Fever Virus in Excretions from Pigs Experimentally Infected with the Georgia 2007/1 Isolate
African swine fever virus (ASFV) causes a lethal haemorrhagic disease of swine which can be transmitted through direct contact with infected animals and their excretions or indirect contact with contaminated fomites. The shedding of ASFV by infected pigs and the stability of ASFV in the environment will determine the extent of environmental contamination. The recent outbreaks of ASF in Europe make it essential to develop disease transmission models in order to design effective control strategies to prevent further spread of ASF. In this study, we assessed the shedding and stability of ASFV in faeces, urine and oral fluid from pigs infected with the Georgia 2007/1 ASFV isolate. The halfâlife of infectious ASFV in faeces was found to range from 0.65 days when stored at 4°C to 0.29 days when stored at 37°C, while in urine it was found to range from 2.19 days (4°C) to 0.41 days (37°C). Based on these halfâlives and the estimated dose required for infection, faeces and urine would be estimated to remain infectious for 8.48 and 15.33 days at 4°C and 3.71 and 2.88 days at 37°C, respectively. The halfâlife of ASFV DNA was 8 to 9 days in faeces and 2 to 3 days in oral fluid at all temperatures. In urine, the halfâlife of ASFV DNA was found to be 32.54 days at 4°C decreasing to 19.48 days at 37°C. These results indicate that ASFV in excretions may be an important route of ASFV transmission.ISSN:1865-1674ISSN:1865-168
[In silico prediction of B- and T-cell epitopes in the CD2v protein of african swine fever virus (African swine fever virus, Asfivirus, Asfarviridae).]
INTRODUCTION: African swine fever virus (ASF) is a large DNA virus that is the only member of the Asfarviridae family. The spread of the ASF virus in the territory of the Russian Federation, Eastern Europe and China indicates the ineffectiveness of existing methods of combating the disease and reinforces the urgent need to create effective vaccines. One of the most significant antigens required for the formation of immune protection against ASF is a serotype-specific CD2v protein. THE PURPOSE OF THE STUDY: This study presents the results of immuno-informatics on the identification of B- and T-cell epitopes for the CD2v protein of the ASF virus using in silico prediction methods. MATERIAL AND METHODS: The primary sequence of the CD2v protein of the ASFV virus strain Georgia 2007/1 (IDFR682468) was analyzed in silico by programs BCPred, NetCTLpan, VaxiJen, PVS and Epitope Conservancy Analysis. RESULTS: Using the BCPred and VaxiJen programs, 4 major B-cell immunogenic epitopes were identified. Analysis of the secretory region of ASF virus CD2v protein in NetCTLpan revealed 5 T-cell epitopes from the 32nd to the 197th position of amino acids that cross-link from the 1st to the 13th allele of the MHC-I of pig Discussion. This study presents the results in silico prediction to identify B- and T-cell epitopes of ASF virus CD2v protein. The soluble region of the CD2v protein can be included in the recombinant polyepitope vaccine against African swine fever. CONCLUSION: B- and T-cell epitopes in the secretory region of the CD2v protein (from 17 to 204 aa) of ASF virus were identified by in silico prediction. An analysis of the conservatism of the identified B- and T-cell epitopes allowed us to develop a map of the distribution of immune epitopes in the CD2v protein sequence
Identification of T-cell epitopes in African swine fever virus CD2v and C-type lectin proteins.
African swine fever (ASF) is an emerging disease threat for the swine industry worldwide. No ASF vaccine is available, and progress is hindered by lack of knowledge concerning the extent of ASF virus (ASFV) strain diversity and the viral antigens conferring type-specific protective immunity in pigs. Previously, we demonstrated that ASFV serotype-specific proteins CD2v (EP402R) and/or C-type lectin (EP153R) are important for protection against homologous ASF infection. Here, we identified six discrete T-cell epitope regions present on CD2v and C-type lectin using IFN-Îł ELISpot assay and PBMCs from ASF immune animals, indicating cellular reactivity to these proteins in the context of ASFV infection and protective immunity. Notably, three of the epitope regions map to previously described serotype-specific signature regions of these proteins. Improved understanding of ASFV protective antigens, relevant epitopes and their diversity in nature will facilitate ASFV subunit vaccine design and development
Identifying climate-sensitive infectious diseases in animals and humans in Northern regions.
BACKGROUND: General knowledge on climate change effects and adaptation strategies has increased significantly in recent years. However, there is still a substantial information gap regarding the influence of climate change on infectious diseases and how these diseases should be identified. From a One Health perspective, zoonotic infections are of particular concern. The climate in Northern regions is changing faster than the global average. This study sought to identify climate-sensitive infectious diseases (CSIs) of relevance for humans and/or animals living in Northern regions. Inclusion criteria for CSIs were constructed using expert assessments. Based on these principles, 37 potential CSIs relevant for Northern regions were identified. A systematic literature search was performed in three databases using an explicit stepwise approach to determine whether the literature supports selection of these 37 potential CSIs. RESULTS: In total, 1275 nominated abstracts were read and categorised using predefined criteria. Results showed that arthropod vector-borne diseases in particular are recognised as having potential to expand their distribution towards Northern latitudes and that tick-borne encephalitis and borreliosis, midge-borne bluetongue and the parasitic infection fasciolosis can be classified as climate-sensitive. Many of the other potential CSIs considered are affected by extreme weather events, but could not be clearly classified as climate-sensitive. An additional literature search comparing awareness of climate influences on potential CSIs between 1997-2006 and 2007-2016 showed an increase in the number of papers mentioning effects of climate change. CONCLUSIONS: The four CSIs identified in this study could be targeted in a systematic surveillance programme in Northern regions. It is evident that climate change can affect the epidemiology and geographical range of many infectious diseases, but there were difficulties in identifying additional CSIs, most likely because other factors may be of equal or greater importance. However, climate-ecological dynamics are constantly under change, and therefore diseases may fall in or out of the climate-sensitive definition over time. There is increasing awareness in the literature of the effects of climate change on infectious diseases over time
Scientific Opinion on African swine fever
The risk for endemicity of ASF in the eastern neighbouring countries of the EU and spread of ASFV to unaffected areas was updated until 31/01/2014. The assessment was based on a literature review and expert knowledge elicitation. The risk that ASF is endemic in Georgia, Armenia and the Russian Federation has increased from moderate to high, particularly due to challenges in outbreak control in the backyard production sector. The risk that ASFV will spread further into unaffected areas from these countries, mainly through movement of contaminated pork, infected pigs or contaminated vehicles, has remained high. In Ukraine and Belarus, the risk for ASF endemicity was considered moderate. Although only few outbreaks have been reported, which have been stamped out, only limited activities are ongoing to facilitate early detection of secondary spread. Further, there is a continuous risk of ASFV re-introduction from the Russian Federation, due to transboundary movements of people, pork or infected wild boar. The number of backyard farms is greatest in the west of Ukraine and westwards spread of ASFV could result in an infected area near the EU border, difficult to control. In Georgia, Armenia and the Russian Federation, the risk for endemicity of ASF in the wild boar population is considered moderate, mainly due to spill-over from the domestic pig population, whereas in Ukraine and Belarus this was considered to be low. In those areas in the Russian Federation where wild boar density is high, this risk may be higher. Intensive hunting pressure in affected wild boar populations may increase the risk for spread, possibly with severe implications across international borders. The risk for different matrices to be infected/contaminated and maintain infectious ASFV at the moment of transportation into the EU was assessed and ranged from very high for frozen meat, to very low for crops