Feline panleukopenia virus (FPV), a globally pervasive and highly pathogenic pathogen, has garnered significant attention recently due to the cross-species transmission of its variants. Despite the vast body of research conducted on FPV, studies exploring its evolutionary history, dynamics, and the factors driving its evolution remain scarce. The pathogenicity of strains with the prevalent mutations (A91S and I101T) in the VP2 protein has also not been fully elucidated. This study conducted a comparative analysis of FPV VP2 sequences sourced from Xinjiang province in China, other provinces in China, and other countries. It was confirmed that the evolutionary rate of FPV approached that of RNA viruses, at approximately 1.13 × 10⁻⁴ substitutions/site/year. The study reconstructed molecular models of the VP2 protein with the A91S and I101T mutations and used viral strains carrying these mutations to perform the animal regression experiment. It was confirmed that isolates with the A91S and I101T mutations could cause typical leukopenia and acute enteritis symptoms, suggesting that the mutant strains still possess certain pathogenicity. This is the first study to report on the evolutionary dynamics of FPV in Xinjiang, China, and it emphasized the importance of continuously monitoring FPV evolutionary dynamics.

The porcine reproductive and respiratory syndrome virus (PRRSV) possesses an inherent ability to adapt to environmental transformations and undergo evolutionary changes, which has imposed significant economic pressure on the global pig industry. Given the potential for recombination among PRRSV genomes and variations in pathogenicity, newly emerging PRRSV isolates are of considerable clinical importance. In this study, we successfully isolated a novel strain named XJ-Z5 from PRRSV-positive samples collected in Xinjiang province in 2022. Through comprehensive genomic sequencing, phylogenetic analysis, and recombination analysis, we confirmed that this strain belongs to the NADC30-like recombinant PRRSV. During pathogenicity tests in piglets, this strain exhibited moderate virulence, causing symptoms such as reduced appetite, persistent fever, and weight loss; however, no mortality cases were observed. Tests conducted at various time points detected the presence of PRRSV nucleic acid in nasal swabs, rectal swabs, tissue samples, and blood, with the highest viral loads found in lung tissue and blood. Serum biochemical tests indicated significant impairment of liver and kidney function. PRRSV antibodies began to appear gradually after 10 days post infection. Hematoxylin and eosin staining revealed substantial pathological changes in lung tissue and lymph nodes. This study enhances our understanding of the epidemiology of PRRSV and underscores the importance of ongoing monitoring and research in light of the challenges posed by the continuous evolution of viral strains. Furthermore, the research emphasizes the urgency of the rapid genomic analysis of emerging viral strains. Through these comprehensive research and monitoring strategies, we aimed to curb the spread of PRRSV more effectively and thus reduce the huge economic losses it caused to the pig industry.

Porcine reproductive and respiratory syndrome virus (PRRSV) infection inflicts enormous economic losses on the global swine industry and imposes significant pressure on agricultural production. However, there are currently no clinically approved effective therapeutics specifically targeting PRRSV. Accordingly, the development of novel antiviral agents against PRRSV is urgently needed. Notably, the structural glycoprotein 4 (GP4) of PRRSV—which plays a crucial role in viral entry into host cells—represents a promising target for antiviral development. Nanobodies, characterized by their small size, structural stability, high affinity, and excellent solubility, have emerged as attractive candidates for next-generation therapeutic development. Yet, to date, no specific nanobodies targeting PRRSV GP4 have been reported. In this study, we isolated GP4-specific nanobodies using phage display technology and investigated their mechanisms underlying viral suppression through a series of in vitro functional assays. Our results demonstrate that Nb6, Nb31, and Nb85 significantly inhibit PRRSV infection by disrupting both viral attachment to host cells and subsequent internalization processes. Collectively, these findings indicate that Nb6, Nb31, and Nb85 hold substantial potential for development as antiviral agents against PRRSV infection.

Bovine viral diarrhea virus (BVDV) is a major pathogen responsible for significant economic losses in the global cattle industry. The diverse transmission routes and the characteristics of asymptomatic infections make it difficult to contain the spread; there is an urgent need to develop new effective antiviral strategies. Nanobodies (Nbs) have become a promising new type of antiviral agent due to their advantages, including small molecular size, stable structure, high specificity, and ease of production. This study successfully screened a specific nanobody, Nb7, targeting the key functional protein NS5A of BVDV using phage display technology. Furthermore, the nanobody was effectively delivered into Madin–Darby bovine kidney (MDBK) cells by fusing it with the cell-penetrating peptide TAT. The results demonstrate that TAT-Nb7, specifically targeting the non-structural protein NS5A of BVDV, significantly inhibits viral replication in MDBK cells. In conclusion, this study indicates that TAT-Nb7 holds promise as a therapeutic candidate for the prevention and control of BVDV infection.

Background: Currently, many detection methods for porcine reproductive and respiratory syndrome virus have been developed, However, the optimal laboratory diagnostic method remains controversial. To evaluate the diagnostic accuracy of PRRSV detection methods based on systematic reviews and meta-analyses, and to determine the optimal strategy for laboratory detection of PRRSV. Method: Articles published between 1 January 2015 and 1 January 2025 were retrieved from multiple databases. Based on different detection methods, the articles were divided into three categories: traditional immunological techniques, molecular amplification techniques, and convergent diagnostic technologies. The sensitivity and specificity of each study were calculated. Diagnostic accuracy was assessed using threshold value definitions, ROC curve analysis, and statistical methods. Meta-analysis was performed using a random-effects model and pooled SROC curves. Stratified analysis and meta-regression were used to address effect size variability caused by differences in detection targets, tissue samples tested, and control trial designs. Results: A total of 55 articles on traditional immunological techniques (involving 17,359 samples), 90 articles on molecular amplification techniques (involving 21,362 samples), and 14 articles on convergent diagnostic technologies (involving 1,289 samples) were included in the meta-analysis. In the 55 studies on traditional immunological techniques, the overall sensitivity was 0.93–0.94 (95% CI), and the overall specificity was 0.92 (95% CI). The area under the ROC curve (AUC) was 0.9686, with an overall diagnostic odds ratio of 115.23 (95% CI 71.38-186.01). In 90 studies on molecular amplification techniques, the overall sensitivity was 0.97 (95% CI 0.96–0.97), and the overall specificity was 0.99 (95% CI 0.99–0.99). The AUC was 0.9951, with an overall diagnostic odds ratio of 1540 (95% CI 883.97-2684.10). In 14 studies on convergent technologies, the overall sensitivity was 0.95 (95% CI 0.92–0.96), and the overall specificity was 0.98 (95% CI 0.96–0.99). The AUC was 0.9910, with an overall diagnostic odds ratio of 503.74 (95% CI 152.78-1660.88). Conclusion: The systematic review and meta-analysis results indicate that traditional immunological techniques, molecular amplification techniques, and convergent diagnostic technologies all exhibit high sensitivity and specificity. Among the three technological platforms, molecular amplification techniques consistently yielded the highest point estimates for sensitivity, specificity, and AUC, along with a markedly higher diagnostic odds ratio.

Current research on glial cells has primarily focused on central nervous system glial cells (CNS glia), with relatively fewer studies on EGCs. Given the critical role of EGCs in maintaining intestinal homeostasis and neural function, this study aimed to investigate their immunomodulatory effects under inflammatory conditions. Primary EGCs were isolated and an inflammatory model was established by treatment with lipopolysaccharide (LPS). Following LPS induction, cellular samples were collected for transcriptomic analysis to identify differentially expressed genes. The analysis revealed that 88 genes were significantly altered, with 60 upregulated and 28 downregulated. Through Gene Ontology (GO) classification, Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway mapping, and protein–protein interaction (PPI) network analysis, several key regulatory genes were identified: chemokine-related genes (IL8L2, IL8L1, CCL4, CCL5, and CX3CL1); negative feedback regulation-related genes (TNFAIP3 and ZC3H12A); homeostasis-maintaining genes (C1QB and LY86); and arachidonic acid metabolism-related genes (PTGS2 and GGT2). Under LPS stimulation without impairing EGC viability, EGCs may recruit immune cells by regulating the aforementioned genes. Additionally, arachidonic acid and its metabolites likely play important regulatory roles in EGC-mediated immunomodulation. These findings provide new theoretical insights and potential targets for further elucidating the pathogenesis of intestinal inflammation and developing targeted therapies.