Circulating Phylotypes of White Spot Syndrome Virus in Bangladesh and Their Virulence

White Spot Syndrome Virus (WSSV) has emerged as one of the most prevalent and lethal viruses globally and infects both shrimps and crabs in the aquatic environment. This study aimed to investigate the occurrence of WSSV in different ghers of Bangladesh and the virulence of the circulating phylotypes. We collected 360 shrimp (Penaeus monodon) and 120 crab (Scylla sp.) samples from the south-east (Cox’s Bazar) and south-west (Satkhira) coastal regions of Bangladesh. The VP28 gene-specific PCR assays and sequencing revealed statistically significant (p < 0.05, Kruskal–Wallis test) differences in the prevalence of WSSV in shrimps and crabs between the study areas (Cox’s Bazar and Satkhira) and over the study periods (2017–2019). The mean Log load of WSSV varied from 8.40 (Cox’s Bazar) to 10.48 (Satkhira) per gram of tissue. The mean values for salinity, dissolved oxygen, temperature and pH were 14.71 ± 0.76 ppt, 3.7 ± 0.1 ppm, 34.11 ± 0.38 °C and 8.23 ± 0.38, respectively, in the WSSV-positive ghers. The VP28 gene-based phylogenetic analysis showed an amino-acid substitution (E→G) at the 167th position in the isolates from Cox’s Bazar (referred to as phylotype BD2) compared to the globally circulating one (BD1). Shrimp PL artificially challenged with BD1 and BD2 phylotypes with filtrates of tissue containing 0.423 × 109 copies of WSSV per mL resulted in a median LT50 value of 73 h and 75 h, respectively. The in vivo trial showed higher mean Log WSSV copies (6.47 ± 2.07 per mg tissue) in BD1-challenged shrimp PL compared to BD2 (4.75 ± 0.35 per mg tissue). Crabs infected with BD1 and BD2 showed 100% mortality within 48 h and 62 h of challenge, respectively, with mean Log WSSV copies of 12.06 ± 0.48 and 9.95 ± 0.37 per gram tissue, respectively. Moreover, shrimp antimicrobial peptides (AMPs), penaeidin and lysozyme expression were lower in the BD1-challenged group compared to BD2 challenged shrimps. These results collectively demonstrated that relative virulence properties of WSSV based on mortality rate, viral load and expression of host immune genes in artificially infected shrimp PL could be affected by single aa substitution in VP28.

Transcriptional response of Wolbachia-transinfected Aedes aegypti mosquito cells to dengue virus at early stages of infection

Mosquito-borne flaviviruses are responsible for viral infections and represent a considerable public health burden. Aedes aegypti is the principal vector of dengue virus (DENV), therefore understanding the intrinsic virus–host interactions is vital, particularly in the presence of the endosymbiont Wolbachia, which blocks virus replication in mosquitoes. Here, we examined the transcriptional response of Wolbachia -transinfected Ae. aegypti Aag2 cells to DENV infection. We identified differentially expressed immune genes that play a key role in the activation of anti-viral defence such as the Toll and immune deficiency pathways. Further, genes encoding cytosine and N6-adenosine methyltransferases and SUMOylation, involved in post-transcriptional modifications, an antioxidant enzyme, and heat-shock response were up-regulated at the early stages of DENV infection and are reported here for the first time. Additionally, several long non-coding RNAs were among the differentially regulated genes. Our results provide insight into Wolbachia -transinfected Ae. aegypti’s initial virus recognition and transcriptional response to DENV infection.

A prognostic model of non small cell lung cancer based on TCGA and ImmPort databases

Bioinformatics methods are used to construct an immune gene prognosis assessment model for patients with non-small cell lung cancer (NSCLC), and to screen biomarkers that affect the occurrence and prognosis of NSCLC. The transcriptomic data and clinicopathological data of NSCLC and cancer-adjacent normal tissues were downloaded from the Cancer Genome Atlas (TCGA) database and the immune-related genes were obtained from the IMMPORT database (http://www.immport.org/); then, the differentially expressed immune genes were screened out. Based on these genes, an immune gene prognosis model was constructed. The Cox proportional hazards regression model was used for univariate and multivariate analyses. Further, the correlations among the risk score, clinicopathological characteristics, tumor microenvironment, and the prognosis of NSCLC were analyzed. A total of 193 differentially expressed immune genes related to NSCLC were screened based on the "wilcox.test" in R language, and Cox single factor analysis showed that 19 differentially expressed immune genes were associated with the prognosis of NSCLC (P < 0.05). After including 19 differentially expressed immune genes with P < 0.05 into the Cox multivariate analysis, an immune gene prognosis model of NSCLC was constructed (it included 13 differentially expressed immune genes). Based on the risk score, the samples were divided into the high-risk and low-risk groups. The Kaplan–Meier survival curve results showed that the 5-year overall survival rate in the high-risk group was 32.4%, and the 5-year overall survival rate in the low-risk group was 53.7%. The receiver operating characteristic model curve confirmed that the prediction model had a certain accuracy (AUC = 0.673). After incorporating multiple variables into the Cox regression analysis, the results showed that the immune gene prognostic risk score was an independent predictor of the prognosis of NSCLC patients. There was a certain correlation between the risk score and degree of neutrophil infiltration in the tumor microenvironment. The NSCLC immune gene prognosis assessment model was constructed based on bioinformatics methods, and it can be used to calculate the prognostic risk score of NSCLC patients. Further, this model is expected to provide help for clinical judgment of the prognosis of NSCLC patients.

The Immune Landscape of Hepatitis B Virus-Related Acute Liver Failure by Integration Analysis

Hepatitis B virus-related acute liver failure (HBV-ALF) is a common type of liver failure, associated with high short-term mortality and morbidity rates. However, the immune landscape of HBV-ALF and its correlation with cell death are currently unknown. Based on 3 Gene Expression Omnibus data sets, infiltrated immune cells were quantified by single-sample gene set enrichment analysis method. The expression levels of immune genes and the abundance of immune cells in liver failure were compared with those in normal liver. The enrichment scores of cell death gene sets from Kyoto Encyclopedia of Genes and Genomes (KEGG) were calculated by gene set variation analysis method, and a protein-protein interaction (PPI) network was constructed using Cytoscape. Besides 21 differentially expressed immune genes, we identified 11 types of differentially infiltrated immune cells in HBV-ALF compared with normal liver. Enriched pathways of these immune genes mainly consisted of chemokine receptors, chemokine binding, interleukin-10 signaling, and TNFs bind their physiological receptors by Reactome pathway analysis. In addition, the enrichment scores of apoptosis and necroptosis pathway instead of autophagy and ferroptosis were increased in liver failure compared with normal liver. PPI network and gene cluster analysis of immune genes and apoptosis and necroptosis genes suggested that hub genes were mainly related to immune response and apoptosis. In summary, our study offers a conceptual framework to understand the immune landscape of HBV-ALF, which might help to improve prognosis.

sRNAs enriched in outer membrane vesicles of pathogenic Flavobacterium psychrophilum interact with immune genes of rainbow trout

Outer membrane vesicles (OMVs) released by gram-negative bacteria during host-pathogen interactions harbor cargos, such as DNA, RNA, toxins, and virulence factors. We hypothesized that sRNAs carried within OMVs of Flavobacterium psychrophilum interact with host immune genes and affect their expression. OMVs were isolated from F. psychrophilum and visualized using transmission electron microscopy (TEM). RNA-Seq datasets generated from whole-cell F. psychrophilum and their OMVs indicated enrichment of specific sRNAs in the OMVs compared to the parent cell. Fluorescent in situ hybridization (FISH) and confocal microscopy confirmed the expression of a randomly chosen sRNA. Integrated RNA-Seq analyses of host transcriptome and bacterial sRNAs on day 5 post-infection of F. psychrophilum -resistant and -susceptible rainbow trout genetic lines revealed 516 protein-coding, 595 lncRNA, and 116 bacterial sRNA differentially expressed (DE) transcripts. Integrated and network analyses of these DE transcripts revealed immune genes targeted by bacterial sRNAs. On the top of these genes, an isoform encoding anaphase-promoting complex subunit 13 (ANAPC13_1) was highly upregulated and exhibited interaction and reciprocal expression with 21 DE sRNAs enriched in OMVs and/or located in pathogenicity islands (PAIs). In vitro treatment of the rainbow trout epithelial cell line RTgill-W1 with OMVs showed signs of cell autolysis accompanied by dynamic changes in expression of host genes when profiled 24h following treatment. The OMV-enriched sRNAs, soFE013584 and soFE002123, showed high interactions with the protection of telomeres 1 gene (POT1); essential for chromosome stability and cellular viability. Modulation of the host gene expression following OMV-treatment, which favors elements from the phagocytic, endocytic, and antigen presentation pathways in addition to HSP70, HSP90, and cochaperone proteins, provided evidence for a potential role of OMVs in boosting the host immune response. In conclusion, our work identified novel microbial targets and inherent characteristics of OMVs that could open up new avenues of treatment and prevention of fish infections.

The Betacoronavirus PHEV Replicates and Disrupts the Respiratory Epithelia and Upregulates Key Pattern Recognition Receptor Genes and Downstream Mediators, Including IL-8 and IFN-λ

The neurotropic betacoronavirus porcine hemagglutinating encephalomyelitis virus (PHEV) primarily infects and replicates in the swine upper respiratory tract, causing vomiting and wasting disease and/or encephalomyelitis in suckling pigs. This study investigated the modulation of key early innate immune genes at the respiratory epithelia in vivo, on tracheal tissue sections from experimentally infected pigs, and in vitro , on air-liquid interface porcine respiratory cell cultures.

microRNA-252 and FoxO repress inflammaging by a dual inhibitory mechanism on Dawdle mediated TGF-β pathway in Drosophila

Inflammaging refers to low-grade, chronically activated innate immunity that has deleterious effects on healthy lifespan. However, little is known about the intrinsic signaling pathway that elicits innate immune genes during aging. Here using Drosophila melanogaster, we profile the microRNA targetomes in young and aged animals, and reveal Dawdle (Daw), an activin-like ligand of the TGF-β pathway, as a physiological target of microRNA-252 (miR-252). We show that miR-252 cooperates with Forkhead box O (FoxO), a conserved transcriptional factor implicated in aging, to repress Daw. Unopposed Daw triggers hyper activation of innate immune genes coupled with a decline in organismal survival. Using adult muscle tissues, single-cell sequencing analysis describes that Daw and its downstream innate immune genes are expressed in distinct cell types, suggesting a cell non-autonomous mode of regulation. We further determine the genetic cascade by which Daw signaling leads to increased Kenny/IKKγ protein, which in turn activates Relish/NF-κB protein and consequentially innate immune genes. Finally, transgenic increase of miR-252 and FoxO pathway factors in wild-type Drosophila extends lifespan and mitigates the induction of innate immune genes in aging. Together, we propose that miR-252 and FoxO promote healthy longevity by cooperative inhibition on Daw mediated inflammaging.