Avian Tembusu virus infection effectively triggers host innate immune response through MDA5 and TLR3-dependent signaling pathways

Additional file 4 ATMUV infection causes significant up-regulation of TLR3 and MDA5. RT-PCR was performed to examine the mRNA expression of TLR3 and MDA5 in CEF (A), chickens (B) and 293T cells (C) at the indicated time after ATMUV infection, respectively

Gut microbiota assemblages of generalist predators are driven by local- and landscape-scale factors

ABSTRACT: The gut microbiomes of arthropods have significant impact on key physiological functions such as nutrition, reproduction, behavior, and health. Spiders are diverse and numerically dominant predators in crop fields where they are potentially important regulators of pests. Harnessing spiders to control agricultural pests is likely to be supported by an understanding of their gut microbiomes, and the environmental drivers shaping microbiome assemblages. This study aimed to deciphering the gut microbiome assembly of these invertebrate predators and elucidating potential implications of key environmental constraints in this process. Here, we used high-throughput sequencing to examine for the first time how the assemblages of bacteria in the gut of spiders are shaped by environmental variables. Local drivers of microbiome composition were globally-relevant input use system (organic production vs. conventional practice), and crop identity (Chinese cabbage vs. cauliflower). Landscape-scale factors, proportion of forest and grassland, compositional diversity, and habitat edge density, also strongly affected gut microbiota. Specific bacterial taxa were enriched in gut of spiders sampled from different settings and seasons. These findings provide a comprehensive insight into composition and plasticity of spider gut microbiota. Understanding the temporal responses of specific microbiota could lead to innovative strategies development for boosting biological control services of predators.info:eu-repo/semantics/publishedVersio

Role of innate immunity in pathophysiology of classical swine fever virus infection

Classical swine fever virus (CSFV) infection causes mild to severe diseases among pigs, depending on the age and immune status of the host and viral strains. CSFV targets various cells, including macrophages and conventional and plasmacytoid dendritic cells. Classical swine fever is one of the most devastating diseases of pigs which leads to high morbidity and mortality, and causes significant economic loss worldwide. In response to infection with CSFV, host innate immune system eliminates the virus by recognizing specific viral molecules via distinct cellular pattern recognition receptors. These receptors trigger downstream intracellular signaling pathways, which regulate the translocation and activation of transcription factors that control the production of cytokines and interferons (IFNs). In turn, these IFNs activate JAK-STAT signaling that governs the transcription of IFN-stimulated genes (ISGs) that play critical roles in antiviral immunity. However, CSFV has evolved different strategies to evade innate immune signaling and can establish persistent infection without being recognized by immune surveillance. In this review, we discuss the current understanding of host innate response to CSFV infection. We also summarize how CSFV evades innate immunity to establish its chronic infection

Evolution of Influenza A Virus by Mutation and Re-Assortment

Influenza A virus (IAV), a highly infectious respiratory pathogen, has continued to be a significant threat to global public health. To complete their life cycle, influenza viruses have evolved multiple strategies to interact with a host. A large number of studies have revealed that the evolution of influenza A virus is mainly mediated through the mutation of the virus itself and the re-assortment of viral genomes derived from various strains. The evolution of influenza A virus through these mechanisms causes worldwide annual epidemics and occasional pandemics. Importantly, influenza A virus can evolve from an animal infected pathogen to a human infected pathogen. The highly pathogenic influenza virus has resulted in stupendous economic losses due to its morbidity and mortality both in human and animals. Influenza viruses fall into a category of viruses that can cause zoonotic infection with stable adaptation to human, leading to sustained horizontal transmission. The rapid mutations of influenza A virus result in the loss of vaccine optimal efficacy, and challenge the complete eradication of the virus. In this review, we highlight the current understanding of influenza A virus evolution caused by the mutation and re-assortment of viral genomes. In addition, we discuss the specific mechanisms by which the virus evolves

Isolation of buffalo poxvirus from clinical case and variations in the genetics of the B5R gene over fifty passages

Outbreaks of buffalopox affect udder and teats, which may ultimately lead to mastitis in dairy buffalo and can significantly compromise the production. In this study, we report isolation of buffalo poxvirus and sequence analysis of the B5R gene collected from the buffalo clinically suspected to be poxvirus infected. The virus was isolated on BHK-21 cell line and was passaged for 50 times, B5R gene was amplified and sequenced using gene-specific primers, and analyzed at both nucleotide and amino acid levels. Phylogenetically, the isolate can be classified close to the previously reported Pakistani and Indian isolates with certain level of differential clustering patterns. Three significant putative mutations (I2K, N64D, and K111E) were observed in the B5R protein. The K111E was common with previous human isolate from Karachi, Pakistan in 2005. These mutations differed from poxviruses reported from the neighboring countries. Some deletion mutations were observed which were recovered in upcoming passages. The K111E mutation suggests potential to cause zoonotic infection in human all over the country

Complete genome sequencing of a velogenic viscerotropic avian paramyxovirus 1 isolated from pheasants (Pucrasia macrolopha) in Lahore, Pakistan

We report the complete genome sequence of avian paramyxovirus 1 (APMV-1) isolated from an acute and highly contagious outbreak in pheasants (Pucrasia macrolopha) in Lahore, Pakistan. Biological and serological characterization showed a velogenic strain of APMV-1, which was further confirmed by the sequence analysis of the cleavage site in the fusion protein. Complete genome sequencing andphylogenetic analysis indicated that this isolate belonged to genotype VII, specifically to subgenotype VIIa, and clustered closely with isolates characterized from Indonesia. Notably, the isolate showed significant differences from previously characterized APMV-1from Pakistani commercial and rural chicken

Host Immune Response to Influenza A Virus Infection

Influenza A viruses (IAVs) are contagious pathogens responsible for severe respiratory infection in humans and animals worldwide. Upon detection of IAV infection, host immune system aims to defend against and clear the viral infection. Innate immune system is comprised of physical barriers (mucus and collectins), various phagocytic cells, group of cytokines, interferons (IFNs), and IFN-stimulated genes, which provide first line of defense against IAV infection. The adaptive immunity is mediated by B cells and T cells, characterized with antigen-specific memory cells, capturing and neutralizing the pathogen. The humoral immune response functions through hemagglutinin-specific circulating antibodies to neutralize IAV. In addition, antibodies can bind to the surface of infected cells and induce antibody-dependent cell-mediated cytotoxicity or complement activation. Although there are neutralizing antibodies against the virus, cellular immunity also plays a crucial role in the fight against IAVs. On the other hand, IAVs have developed multiple strategies to escape from host immune surveillance for successful replication. In this review, we discuss how immune system, especially innate immune system and critical molecules are involved in the antiviral defense against IAVs. In addition, we highlight how IAVs antagonize different immune responses to achieve a successful infection

Antibiotic nitrofurazone drives the functional dynamics of periphytic protozoan fauna in marine environments

The use of functional traits of a community as a method to measure its functional dynamics in response to environmental change has gained attention because trait-based approaches offer systematic opportunities to understand the interactions between species diversity and ecosystem function. However, the relationship between functional traits of periphytic protozoa and contamination of aquatic habitats with antibiotics is poorly understood. In this study, we investigated the influence of the antibiotic nitrofurazone on functional traits of marine periphytic protozoan fauna. For this purpose, the protozoan assemblages were collected from coastal waters of the Yellow Sea at Qingdao, northern China, during four seasons of a one-year cycle using glass microscope slides as artificial substrates. The test protozoan communities were then exposed to various treatments of nitrofurazone in laboratory bioassay experiments. Our results demonstrated that the modalities of the functional traits of protozoan communities were generally driven by nitrofurazone toxicity. Briefly, R-mode linked to Q-mode (RLQ) and fourth-corner analyses revealed strong positive correlations between functional traits and nitrofurazone treatments. Trait syndromes in terms of body length, width, weight, height, and size to volume ratios were significantly influenced by nitrofurazone exposure. In particular, small and medium body size species of different feeding types, i.e., algivores, bacterivores, raptors or non-selectives, were more sensitive than other protozoan species to higher concentrations of nitrofurazone. Our findings demonstrate that antibiotic toxicity is likely to affect periphytic protozoan community function, shape the functional processes, and induce toxic responses in the community. The findings of this study suggest that periphytic protozoan communities and their functional traits are suitable bioindicators for evaluating the ecotoxicity of nitrofurazone in marine environments.This work research was supported by the National Natural Science Foundation of China, China (42177264, 31672308), Shantou University Scientific Research Foundation for Talents, China (NTF19044), and 2020 Li Ka Shing Foundation Cross-Disciplinary Research Grant, China (2020LKSFG03E).Peer reviewe