Isolation and Genomic Characterization of a Novel Porcine Reproductive and Respiratory Syndrome Virus 1 from Severely Diseased Piglets in China in 2024.

Since the first isolation of the porcine reproductive and respiratory syndrome virus 1 (PRRSV-1) BJEU06-1 strain from a Beijing pig farm in 2006, more and more PRRSV-1 isolates have been identified in China. In this study, we performed the routine detection of PRRSV-1 using 1521 clinical samples collected in 12 provinces/cities from February 2022 to May 2024. Only three lung samples from severely diseased piglets collected in January 2024 were detected as PRRSV-1-positive (0.

A nucleocapsid monoclonal antibody based sandwich ELISA for the general detection of both PRRSV-2 and PRRSV-1.

Porcine reproductive and respiratory syndrome virus (PRRSV) causes reproductive failure in sows and respiratory disease in growing pigs, leading to significant economic losses worldwide. Due to the constant mutation and recombination, PRRSV exhibits significant genetic diversity, the general detection of all PRRSV-2 and PRRSV-1 strains is thus needed. In our study, four monoclonal antibodies (mAbs) against PRRSV nucleocapsid (N) protein were generated and the precise and novel B cell epitopes (KPHF and HHTVR) were identified.

The replication efficacy of NADC34-like porcine reproductive and respiratory syndrome virus 2 is not directly associated with the pathogenicity.

NADC34-like porcine reproductive and respiratory syndrome virus 2 (NADC34-like PRRSV-2) is currently a major prevalent strain in Chinese swine industry. Within which, recombination events are frequently detected. Previous studies have shown that the pathogenicity of NADC34-like PRRSV-2 isolates is highly variable.

Identification of a New Conserved Antigenic Epitope by Specific Monoclonal Antibodies Targeting the African Swine Fever Virus Capsid Protein p17.

African swine fever (ASF) has widely spread around the world in the last 100 years since its discovery. The African swine fever virus (ASFV) particles are made of more than 150 proteins, with the p17 protein encoded by the D117L gene serving as one of the major capsid proteins and playing a crucial role in the virus's morphogenesis and immune evasion. Thus, monoclonal antibody (mAb) targeting p17 is important for the research and detection of ASFV infection.

How Does African Swine Fever Virus Evade the cGAS-STING Pathway?

African swine fever (ASF), a highly infectious and devastating disease affecting both domestic pigs and wild boars, is caused by the African swine fever virus (ASFV). ASF has resulted in rapid global spread of the disease, leading to significant economic losses within the swine industry. A significant obstacle to the creation of safe and effective ASF vaccines is the existing knowledge gap regarding the pathogenesis of ASFV and its mechanisms of immune evasion.

Positivity Status and Molecular Characterization of Porcine Parvoviruses 1 Through 8 (PPV1-PPV8) from Slaughtered Pigs in China.

Porcine parvoviruses one through eight (PPV1-PPV8) are prevalent in Chinese swine herds. However, the infection status of all these PPVs in slaughtered pigs is still unclarified. In this study, we detected PPV1-PPV8 in 353 tissue samples collected from slaughtered pigs from six regions of China in 2023.

Porcine TLR8 signaling and its anti-infection function are disturbed by immune checkpoint receptor TIM-3 via inhibition of P13K-AKT pathway.

Toll-like receptor 8 (TLR8), an important innate immune receptor recognizing single stranded RNA and the antiviral imidazoquinoline compounds, can activate intracellular signaling pathway and produce an inflammatory response to kill and eliminate pathogens. However, the molecular regulation mechanisms of TLR8 signaling and its anti-infection activity are not fully elucidated. Our previous transcriptome analysis of porcine TLR8 (pTLR8) signaling suggested the immune checkpoint receptor TIM-3 as the potential regulator for pTLR8.

Development of visual detection of African swine fever virus using CRISPR/LwCas13a lateral flow strip based on structural protein gene D117L.

African swine fever virus (ASFV) is a large double stranded DNA arbovirus that is highly contagious and seriously endangers domestic and wild pigs. In the past decade, African swine fever (ASF) has spread in many countries in the Caucasus, Russian Federation, Eastern Europe and Asia, causing significant losses to the pig industry. At present, there is a lack of effective vaccine and treatment for ASF.

A chimeric porcine reproductive and respiratory syndrome virus 1 strain containing synthetic ORF2-6 genes can trigger T follicular helper cell and heterologous neutralizing antibody responses and confer enhanced cross-protection.

The prevalence of porcine reproductive and respiratory syndrome virus 1 (PRRSV1) isolates has continued to increase in Chinese swine herds in recent years. However, no effective control strategy is available for PRRSV1 infection in China. In this study, we generated the first infectious cDNA clone (rHLJB1) of a Chinese PRRSV1 isolate and subsequently used it as a backbone to construct an ORF2-6 chimeric virus (ORF2-6-CON).

Systematic analysis of the codon usage patterns of African swine fever virus genome coding sequences reveals its host adaptation phenotype.

African swine fever (ASF) is a severe haemorrhagic disease caused by the African swine fever virus (ASFV), transmitted by ticks, resulting in high mortality among domestic pigs and wild boars. The global spread of ASFV poses significant economic threats to the swine industry. This study employs diverse analytical methods to explore ASFV's evolution and host adaptation, focusing on codon usage patterns and associated factors.

Rapid Visual Detection of African Swine Fever Virus with a CRISPR/Cas12a Lateral Flow Strip Based on Structural Protein Gene D117L.

African swine fever virus (ASFV) is a large double-stranded DNA virus that is highly infectious and seriously affects domestic pigs and wild boars. African swine fever (ASF) has caused huge economic losses to endemic countries and regions. At present, there is still a lack of effective vaccines and therapeutics.

Cytochrome P450 2D6 profiles and anti-relapse efficacy of tafenoquine against in Australian Defence Force personnel.

infections and relapses remain a major health problem for malaria-endemic countries, deployed military personnel, and travelers. Presumptive anti-relapse therapy and radical cure using the 8-aminoquinoline drugs primaquine and tafenoquine are necessary to prevent relapses. Although it has been demonstrated that the efficacy of primaquine is associated with Cytochrome P450 2D6 (CYP2D6) activity, there is insufficient data on the role of CYP2D6 in the anti-relapse efficacy of tafenoquine.

Epidemiologic and Genomic Characterizations of Porcine Kobuviruses in Diarrheic and Healthy Pigs.

Porcine kobuvirus (PKV) is an enteric virus commonly detected in both diarrheic and healthy pigs. Little is known about the role of PKV in enteric diseases. In this study, an epidemiological investigation based on 324 intestinal samples collected from six provinces of China during the period of 2018 to 2022 was performed, and showed that PKV has an overall 65.

How Does cGAS Avoid Sensing Self-DNA under Normal Physiological Conditions?

cGAS is a cytosolic DNA sensor that activates innate immune responses by producing the second messenger 2'3'-cGAMP, which activates the adaptor STING. cGAS senses dsDNA in a length-dependent but sequence-independent manner, meaning it cannot discriminate self-DNA from foreign DNA. In normal physiological conditions, cellular DNA is sequestered in the nucleus by a nuclear envelope and in mitochondria by a mitochondrial membrane.

Porcine IKKε is involved in the STING-induced type I IFN antiviral response of the cytosolic DNA signaling pathway.

The cyclic GMP-AMP synthase and stimulator of interferon (IFN) genes (cGAS-STING) pathway serves as a crucial component of innate immune defense and exerts immense antiviral activity by inducing the expression of type I IFNs. Currently, STING-activated production of type I IFNs has been thought to be mediated only by TANK-binding kinase 1 (TBK1). Here, we identified that porcine IKKε (pIKKε) is also directly involved in STING-induced type I IFN expression and antiviral response by using IKKε porcine macrophages.

Multiple Porcine Innate Immune Signaling Pathways Are Involved in the Anti-PEDV Response.

Porcine epidemic diarrhea virus (PEDV) has caused great damage to the global pig industry. Innate immunity plays a significant role in resisting viral infection; however, the exact role of innate immunity in the anti-PEDV response has not been fully elucidated. In this study, we observed that various porcine innate immune signaling adaptors are involved in anti-PEDV (AJ1102-like strain) activity in transfected Vero cells.

The Chicken cGAS-STING Pathway Exerts Interferon-Independent Antiviral Function via Cell Apoptosis.

It has been recently recognized that the DNA sensing innate immune cGAS-STING pathway exerts an IFN-independent antiviral function; however, whether and how chicken STING (chSTING) exerts such an IFN-independent antiviral activity is still unknown. Here, we showed that chSTING exerts an antiviral activity in HEK293 cells and chicken cells, independent of IFN production. chSTING was able to trigger cell apoptosis and autophagy independently of IFN, and the apoptosis inhibitors, rather than autophagy inhibitors, could antagonize the antiviral function of chSTING, suggesting the involvement of apoptosis in IFN-independent antiviral function.

Efficacy of a porcine reproductive and respiratory syndrome virus 1 (PRRSV-1) natural recombinant against a heterologous PRRSV-1 isolate both clustered within the subgroup of BJEU06-1-like isolates.

Porcine reproductive and respiratory syndrome virus 1 (PRRSV-1) has been prevalent in more than 20 provinces of China. However, no PRRSV-1-specific vaccine is commercially available in China. To evaluate the feasibility of using a low virulent PRRSV-1 isolate against potential outbreaks caused by virulent Chinese PRRSV-1 isolates, here we evaluated the efficacy of a low virulent PRRSV-1 HLJB1 strain isolated in 2014 as live vaccine against a virulent PRRSV-1 SD1291 strain isolated in 2022.

Genomic Characterizations of Porcine Epidemic Diarrhea Viruses (PEDV) in Diarrheic Piglets and Clinically Healthy Adult Pigs from 2019 to 2022 in China.

Porcine epidemic diarrhea virus (PEDV) is a major causative pathogen of diarrheic disease. In this study, the prevalence and evolution of PEDV was evaluated using intestinal samples collected from six provinces of China in 2019-2022. PEDV could not only be detected in diarrheic piglets but also in adult pigs without enteric diseases.

A potent CD8 T-cell response may be associated with partial cross-protection conferred by an attenuated Chinese HP-PRRSV vaccine against NADC30-like PRRSV challenge.

Porcine reproductive and respiratory syndrome virus (PRRSV) is one of the most devastating pathogens to the global swine industry. Many commercial PRRSV vaccines, originally designed to provide homologous protection, have shown partial protection against heterologous strains. However, the protective immune mechanisms mediated by these PRRSV vaccines are not fully understood.

Manganese Mediates Its Antiviral Functions in a cGAS-STING Pathway Independent Manner.

The innate immune system is the first line of host defense sensing viral infection. Manganese (Mn) has recently been found to be involved in the activation of the innate immune DNA-sensing cGAS-STING pathway and subsequent anti-DNA virus function. However, it is still unclear whether Mn mediates host defense against RNA viruses.

Development of Specific Monoclonal Antibodies against Porcine RIG-I-like Receptors Revealed the Species Specificity.

The RIG-I-like receptors (RLRs) play critical roles in sensing and combating viral infections, particularly RNA virus infections. However, there is a dearth of research on livestock RLRs due to a lack of specific antibodies. In this study, we purified porcine RLR proteins and developed monoclonal antibodies (mAbs) against porcine RLR members RIG-I, MDA5 and LGP2, for which one, one and two hybridomas were obtained, respectively.

The Porcine Cyclic GMP-AMP Synthase-STING Pathway Exerts an Unusual Antiviral Function Independent of Interferon and Autophagy.

The innate immune DNA-sensing cyclic GMP-AMP synthase (cGAS)-stimulator of interferon (IFN) gene (STING) pathway exerts strong antiviral activity through downstream IFN production; however, it has been recently recognized that an IFN-independent activity of STING also plays an important role in antiviral functions. Nevertheless, the IFN-independent antiviral activity of STING is not fully understood. Here, we showed that porcine STING (pSTING) played a critical role against herpes simplex virus 1 (HSV-1) and vesicular stomatitis virus (VSV) infections, and IFN-defective mutants, including pSTING pLxIS sub, S365A, and △CTT, all exhibited similar antiviral functions, compared to wild-type (WT) pSTING.