Following two human infections with the H10N3 avian influenza virus (AIV) in 2021 and 2022, a third case was discovered in Yunnan, China, in 2024, raising concerns about the potential for future pandemics. Recent studies have indicated that novel H10N3 viruses are highly pathogenic in mice and can be transmitted between guinea pigs via respiratory droplets without prior adaptation. However, the biological characteristics of novel H10N3 in poultry have not been fully elucidated.
View Article and Find Full Text PDFInfluenza A virus (IAV) infection initiates a complex interplay of cell death modalities, including apoptosis, necroptosis, pyroptosis, and their integration, known as PANoptosis, which significantly impacts host immune responses and tissue integrity. These pathways are intricately regulated by viral proteins and host factors, contributing to both viral clearance and pathogenesis-related tissue damage. This review comprehensively explores the molecular mechanisms underlying these cell death processes in influenza infection.
View Article and Find Full Text PDFNewcastle disease virus (NDV) poses a significant threat to the poultry industry, with the emergence of genotype VII NDV leading to extensive outbreaks and economic losses. Vaccination is the primary means of controlling NDV, but the presence of maternal antibodies (MDAs) can interfere with the immunological effect of live virus vaccines. Thus, we constructed a chimeric NDV live virus vaccine, LX-OAI4S, by replacing the extracellular regions of the F and HN genes of the NDV LX strain with the corresponding regions of the A-VII vaccine strain.
View Article and Find Full Text PDFCaspase-8, an aspartate-specific cysteine protease that primarily functions as an initiator caspase to induce apoptosis, can downregulate innate immunity in part by cleaving RIPK1 and IRF3. However, patients with caspase-8 mutations or deficiency develop immunodeficiency and are prone to viral infections. The molecular mechanism underlying this controversy remains unknown.
View Article and Find Full Text PDFCellular cholesterol plays an important role in influenza A virus (IAV) endocytosis and replication. However, how IAV infection regulates cholesterol biosynthesis remains poorly understood. Here, we report that IAV infection activates SREBP2 and induces the expression of HMGCR, a rate-limiting enzyme in cholesterol synthesis pathway.
View Article and Find Full Text PDFThe haemagglutinin-neuraminidase (HN) protein, a vital membrane glycoprotein, plays a pivotal role in the pathogenesis of Newcastle disease virus (NDV). Previously, we demonstrated that a mutation in the HN protein is essential for the enhanced virulence of JS/7/05/Ch, a velogenic variant NDV strain originating from the mesogenic vaccine strain Mukteswar. Here, we explored the effects of the HN protein during viral infection in vitro using three viruses: JS/7/05/Ch, Mukteswar, and an HN-replacement chimeric NDV, JS/MukHN.
View Article and Find Full Text PDFLysosomes are acidic organelles that mediate the degradation and recycling of cellular waste materials. Damage to lysosomes can cause lysosomal membrane permeabilization (LMP) and trigger different types of cell death, including apoptosis. Newcastle disease virus (NDV) can naturally infect most birds.
View Article and Find Full Text PDFAvian influenza viruses can cross species barriers and adapt to mammals. The H7N9 subtype AIV that emerged in China in 2013 caused 1568 human infections, with a mortality rate of nearly 40%. We conducted a retrospective analysis of H7N9 viruses that were isolated in live poultry markets in 2013.
View Article and Find Full Text PDFBiochim Biophys Acta Mol Basis Dis
February 2024
Background: Influenza is a clinically important infectious disease with a high fatality rate, which always results in severe pneumonia. Mesenchymal stem cells (MSCs) exhibit promising therapeutic effects on severe viral pneumonia, but whether MSCs prevent virus infection and contribute to the prevention of influenza remains unknown.
Methods: ICR mice were pretreated with human umbilical cord (hUC) MSCs and then infected with the influenza H7N9 virus.
Low pathogenic (LP) H7N9 avian influenza virus (AIV) emerged in 2013 and had spread widely over several months in China, experienced a noteworthy reduction in isolation rate in poultry and human since 2017. Here, we examined the transmission of H7N9 viruses to better understand viral spread and dissemination mechanisms. Three out of four viruses (2013-2016) could transmit in chickens through direct contact, and airborne transmission was confirmed in the JT157 (2016) virus.
View Article and Find Full Text PDFH9N2 subtype avian influenza virus (AIV) can transmit by direct as well as airborne contacts. It has been widespread in poultry and continued to contribute to zoonotic spillover events by providing its six internal genes for the reassortment of novel influenza viruses (eg, H7N9) that infect poultry and humans. Compared to H7N9, H9N2 virus displays an efficient airborne transmissibility in poultry, but the mechanisms of transmission difference have been insufficiently studied.
View Article and Find Full Text PDFThe haemagglutinin-neuraminidase (HN) protein plays a crucial role in the infectivity and virulence of Newcastle disease virus (NDV). In a previous study, the mutant HN protein was identified as a crucial virulence factor for the velogenic variant NDV strain JS/7/05/Ch, which evolved from the prototypic vaccine strain Mukteswar. Furthermore, macrophages are the main susceptible target cells of NDV.
View Article and Find Full Text PDFH9N2 avian influenza viruses (AIVs) pose an increasing threat to the poultry industry worldwide and have pandemic potential. Vaccination has been principal prevention strategy to control H9N2 in China since 1998, but vaccine effectiveness is persistently challenged by the emergence of the genetic and/or antigenic variants. Here, we analysed the genetic and antigenic characteristics of H9N2 viruses in China, including 70 HA sequences of H9N2 isolates from poultry, 7358 from online databases during 2010-2020, and 15 from the early reference strains.
View Article and Find Full Text PDFTimeseries representation underpin our ability to understand and predict the change of natural system. Series are often predicated on our choice of highly redundant factors, and in fact, the system is driven by a much smaller set of latent intrinsic keys. It means that a better representation of data makes points in phase space clearly for researchers.
View Article and Find Full Text PDFMicrobiol Spectr
February 2023
The H7N9 subtype of influenza virus can infect birds and humans, causing great losses in the poultry industry and threatening public health worldwide. However, H7N9 infection in other mammals has not been reported yet. In the present study, one H7N9 subtype influenza virus, A/camel/Inner Mongolia/XL/2020 (XL), was isolated from the nasal swabs of camels in Inner Mongolia, China, in 2020.
View Article and Find Full Text PDFAs a multifunctional protein, the hemagglutinin-neuraminidase (HN) protein of Newcastle disease virus (NDV) is involved in various biological functions. A velogenic genotype III NDV JS/7/05/Ch evolving from the mesogenic vaccine strain Mukteswar showed major amino acid (aa) mutations in the HN protein. However, the precise biological significance of the mutant HN protein remains unclear.
View Article and Find Full Text PDFH9N2 avian influenza viruses (AIVs) circulate globally in poultry and have become the dominant AIV subtype in China in recent years. Previously, we demonstrated that the H9N2 virus (A/chicken/Eastern China/SDKD1/2015) naturally harbors a mammalian-adaptive molecular factor (627K) in the PB2 protein and is weakly pathogenic in mice. Here, we focused on new markers for virulence in mammals.
View Article and Find Full Text PDFCommercial inactivated vaccines against H9N2 avian influenza (AI) have been developed in China since 1990s and show excellent immunogenicity with strong HI antibodies. However, currently approved vaccines cannot meet the clinical demand for a live-vectored vaccine. Newcastle disease virus (NDV) vectored vaccines have shown effective protection in chickens against H9N2 virus.
View Article and Find Full Text PDFThe extended co-circulation of H5 subtype highly pathogenic avian influenza (HPAI) viruses and H9N2 low pathogenic avian influenza (LPAI) viruses has inevitably facilitated gene reassortment between the two subtypes in fields. And, novel reassortant H5NX viruses harboring partial or even whole sets of H9N2 internal genes have continuously been detected, such as clade 2.3.
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