Analyses of the spleen proteome of chickens infected with Marek's disease virus

Splenic proteome profiling in response to Marek's disease virus strain GX0101 infection

Marek's disease virus (MDV) strain GX0101 was the first reported field strain of recombinant gallid herpesvirus type 2 (GaHV-2). However, the splenic proteome of MDV-infected chickens remains unclear. In this study, a total of 28 1-day-old SPF chickens were intraperitoneally injected with chicken embryo fibroblast (CEF) containing 2000 PFU GX0101. Additionally, a control group, consisting of four one-day-old SPF chickens, received intraperitoneal equal doses of CEF. Blood and various tissue samples were collected at different intervals (7, 14, 21, 30, 45, 60, and 90 days post-infection; dpi) for histopathological, real-time PCR, and label-free quantitative analyses. The results showed that the serum expressions of MDV-related genes, meq and gB, peaked at 45 dpi. The heart, liver, and spleen were dissected at 30 and 45 dpi, and their hematoxylin-eosin staining indicated that virus infection compromised the normal organizational structure at 45 dpi. Particularly, the spleen structure was severely damaged, and the lymphocytes in the white medulla were significantly reduced. Furthermore, liquid chromatography-mass spectrometry (LC-MS) and label-free techniques were used to analyze the difference in splenic proteome profiles of the experimental and control groups at 30 and 45 dpi. Proteomic analysis identified 1660 and 1244 differentially expressed proteins (DEPs) at 30 and 40 dpi, respectively, compared with the uninfected spleen tissues. According to GO analysis, these DEPs were involved in processes such as organelle organization, cellular component biogenesis, cellular component assembly, anion binding, small molecule binding, metal ion binding, cation binding, cytosol, nuclear part, etc. Additionally, KEGG analysis indicated that the following pathways were linked to MDV-induced inflammation, apoptosis, and tumor: Wnt, Hippo, AMPK, cAMP, Notch, TGF-β, PI3K-Akt, Rap1, Ras, Calcium, NF-κB, PPAR, cGMP-PKG, Apoptosis, VEGF, mTOR, FoxO, TNF, JAK-STAT, MAPK, Prion disease, T cell receptor, and B cell receptor. We finally screened 674 DEPs that were linked to MDV infection in spleen tissue. This study improves our understanding of the MDV response mechanism in the spleen.

Comparative RNA-Seq analysis reveals insights in Salmonella disease resistance of chicken; and database development as resource for gene expression in poultry

Salmonella, one of the major infectious diseases in poultry, causes considerable economic losses in terms of mortality and morbidity, especially in countries that lack effective vaccination programs. Besides being resistant to diseases, indigenous chicken breeds are also a potential source of animal protein in developing countries. For understanding the disease resistance, an indigenous chicken line Kashmir faverolla, and commercial broiler were selected. RNA-seq was performed after challenging the chicken with Salmonella Typhimurium. Comparative differential expression results showed that following infection, a total of 3153 genes and 1787 genes were differentially expressed in the liver and spleen, respectively. The genes that were differentially expressed included interleukins, cytokines, NOS2, Avβ-defensins, toll-like receptors, and other immune-related gene families. Most of the genes and signaling pathways involved in the innate and adaptive immune responses against bacterial infection were significantly enriched in the Kashmir faverolla. Pathway analysis revealed that most of the enriched pathways were MAPK signaling pathway, NOD-like receptor signaling pathway, TLR signaling pathway, PPAR signaling pathway, endocytosis, etc. Surprisingly some immune-related genes like TLRs were upregulated in the susceptible chicken breed. On postmortem examination, the resistant birds showed small lesions in the liver compared to large necrotic lesions in susceptible birds. The pathological manifestations and RNA sequencing results suggest a balancing link between resistance and infection tolerance in Kashmir faverolla. Here we also developed an online Poultry Infection Database (https://skuastk.org/pif/index.html), the first publicly available gene expression resource for disease resistance in chickens. The available database not only shows the data for gene expression in chicken tissues but also provides quick search, visualization and download capacity.

Comparison of Selection Signatures between Korean Native and Commercial Chickens Using 600K SNP Array Data

Korean native chickens (KNCs) comprise an indigenous chicken breed of South Korea that was restored through a government project in the 1990s. The KNC population has not been developed well and has mostly been used to maintain purebred populations in the government research institution. We investigated the genetic features of the KNC population in a selection signal study for the efficient improvement of this breed. We used 600K single nucleotide polymorphism data sampled from 191 KNCs (NG, 38; NL, 29; NR, 52; NW, 39; and NY, 33) and 54 commercial chickens (Hy-line Brown, 10; Lohmann Brown, 10; Arbor Acres, 10; Cobb, 12; and Ross, 12). Haplotype phasing was performed using EAGLE software as the initial step for the primary data analysis. Pre-processed data were analyzed to detect selection signals using the ‘rehh’ package in R software. A few common signatures of selection were identified in KNCs. Most quantitative trait locus regions identified as candidate regions were associated with traits related to reproductive organs, eggshell characteristics, immunity, and organ development. Block patterns with high linkage disequilibrium values were observed for LPP, IGF11, LMNB2, ERBB4, GABRB2, NTM, APOO, PLOA1, CNTN1, NTSR1, DEF3, CELF1, and MEF2D genes, among regions with confirmed selection signals. NL and NW lines contained a considerable number of selective sweep regions related to broilers and layers, respectively. We recommend focusing on improving the egg and meat traits of KNC NL and NW lines, respectively, while improving multiple traits for the other lines.

Proteomics reveals the effect of type I interferon on the pathogenicity of duck hepatitis A virus genotype 3 in Pekin ducks

Duck hepatitis A virus genotypes 3 (DHAV-3) has become the most prevalent pathogen of duck viral hepatitis (DVH) in Asian duck industry in recent years. Previous studies on the pathogenic mechanism of DHAV-3 mainly focused on examine host gene expression levels. However, the study about host protein expression levels has not been reported. For this, proteomics analysis on livers of infected 7-day-old Pekin ducks with DHAV-3 112803 strain was performed to screen differentially expressed proteins. A total of 3,385 proteins were identified, and we found 39 proteins in the challenged group (CH) were significantly up-regulated and 15 proteins were significantly down-regulated in comparison with control group (CON). GO results showed that 9 of the top 20 GO terms were involved in type I interferon regulation, and the KEGG pathway enrichment results showed that innate immune responses were significantly enriched, such as RIG-1-like, Toll-like and NOD-like receptor signaling pathways. Notably, interaction between 11 up-regulation proteins promoted interferon-induced protein synthesis and supported viral genome replication, which could aggravate inflammatory response and liver damage. These findings, together with RT-qPCR verification of related genes, support the view that the type I interferon may play an extremely important role in the pathogenic mechanism of DHAV-3.

Quantitative Proteomics Analysis Revealed Compromised Chicken Dendritic Cells Function at Early Stage of Very Virulent Infectious Bursal Disease Virus Infection

Chicken dendritic cells (DCs) have been demonstrated to be susceptible to infectious bursal disease virus (IBDV), a causative agent of acute and immunosuppressed disease in young chicks known as infectious bursal disease. Further functional characterization of IBDV-infected DCs of chickens is required to provide a better understanding on the influence of the virus on chicken bone marrow-derived dendritic cells (BM-DCs) following very virulent (vv) IBDV infection. Membrane proteins of BM-DCs were extracted and the proteins were further denatured and reduced before performing labeling with isobaric tags for relative and absolute quantitation. The differential expression protein profiles were identified and quantified using liquid chromatography coupled with tandem mass spectrometry, and later validated using flow cytometry and real-time reverse transcriptase PCR. The analysis has identified 134 differentially regulated proteins from a total of 283 proteins (cutoff values of ≤0.67, ≥1.5, and ProtScore >1.3 at 95% confidence interval), which produced high-yield membrane fractions. The entry of vvIBDV into the plasma membrane of BM-DCs was observed at 3 hr postinfection by the disruption of several important protein molecule functions, namely apoptosis, RNA/DNA/protein synthesis, and transport and cellular organization, without the activation of proteins associated with signaling. At the later stage of infection, vvIBDV induced expression of several proteins, namely CD200 receptor 1-A, integrin alpha-5, HSP-90, cathepsin, lysosomal-associated membrane protein, and Ras-related proteins, which play crucial roles in signaling, apoptosis, stress response, and antigen processing as well as in secretion of danger-associated proteins. These findings collectively indicated that the chicken DCs are expressing various receptors regarded as potential targets for pathogen interaction during viral infection. Therefore, fundamental study of the interaction of DCs and IBDV will provide valuable information in understanding the role of professional antigen-presenting cells in chickens and their molecular interactions during IBDV infection and vaccination.

Screening of differentially expressed immune-related genes from spleen of broilers fed with probiotic Bacillus cereus PAS38 based on suppression subtractive hybridization

The aim of this study was to construct the spleen differential genes library of broilers fed with probiotic Bacillus cereus PAS38 by suppression subtractive hybridization (SSH) and screen the immune-related genes. Sixty seven-day-old broilers were randomly divided into two groups. The control group was fed with basal diet, and the treated group was fed with basal diet containing Bacillus cereus PAS38 1×10⁶ CFU/g. Spleen tissues were taken and extracted its total RNA at 42 days old, then SSH was used to construct differential gene library and screen immune-related genes. A total of 119 differentially expressed sequence tags (ESTs) were isolated by SSH and 9 immune-related genes were screened out by Gene ontology analysis. Nine differentially expressed genes were identified by qRT-PCR. JCHAIN, FTH1, P2RX7, TLR7, IGF1R, SMAD7, and SLC7A6 were found to be significantly up-regulated in the treated group. Which was consistent with the results of SSH. These findings imply that probiotic Bacillus cereus PAS38-induced differentially expressed genes in spleen might play an important role in the improvement of immunity for broilers, which provided useful information for further understanding of the molecular mechanism of probiotics responsible to affect the poultry immunity.

Analysis of the spleen proteome of chickens infected with reticuloendotheliosis virus

Infection with reticuloendotheliosis virus (REV), a gammaretrovirus in the family Retroviridae, can result in immunosuppression and subsequent increased susceptibility to secondary infections. In the present study, we identified differentially expressed proteins in the spleens of chickens infected with the REV-A HLJ07I strain, using two-dimensional gel electrophoresis on samples from time points coinciding with different phases of the REV life cycle. Differentially expressed proteins were identified using one-dimensional liquid chromatography electrospray ionization tandem mass spectrometry (1D LC ESI MS/MS). Comparative analysis of multiple gels revealed that the majority of changes occurred at early stages of infection. In total, 60 protein spots representing 28 host proteins were detected as either quantitatively (false discovery rate [FDR] ≤0.05 and fold change ≥2) or qualitatively differentially expressed at least once during different sampling points. The differentially expressed proteins identified in this study included antioxidants, molecular chaperones, cellular metabolism, formation of the cytoskeleton, signal transduction, cell proliferation and cellar aging. The present findings provide a basis for further studies to elucidate the role of these proteins in REV-host interactions. This could lead to a better understanding of REV infection mechanisms that cause immune suppression.

Quantitative iTRAQ LC-MS/MS proteomics reveals the proteome profiles of DF-1 cells after infection with subgroup J Avian leukosis virus

Avian leukosis virus subgroup J (ALV-J) is an avian oncogenic retrovirus that can induce various clinical tumors and has caused severe economic losses in China. To improve our understanding of the host cellular responses to virus infection and the pathogenesis of ALV-J infection, we applied isobaric tags for relative and absolute quantification (iTRAQ) labeling coupled with multidimensional liquid chromatography-tandem mass spectrometry to detect the protein changes in DF-1 cells infected and mock-infected with ALV-J. A total of 75 cellular proteins were significantly changed, including 33 upregulated proteins and 42 downregulated proteins. The reliability of iTRAQ-LC MS/MS was confirmed via real-time PCR. Most of these proteins were related to the physiological functions of metabolic processes, biosynthetic processes, responses to stimuli, protein binding, signal transduction, cell cytoskeleton, and so forth. We also found some proteins that play important roles in apoptosis and oncogenicity. The differentially expressed proteins identified may provide valuable information to elucidate the pathogenesis of virus infection and virus-host interactions.

Proteomic alteration of PK-15 cells after infection by porcine circovirus type 2

Porcine circovirus type 2 (PCV2) has been identified as the essential causal agent of post-weaning multisystemic wasting syndrome, which has spread worldwide. To discover cellular protein responses of PK-15 cells to PCV2 infection, two-dimensional liquid chromatography-tandem mass spectrometry (MS) coupled with isobaric tags for relative and absolute quantification (iTRAQ) labeling was employed to quantitatively identify the proteins that were differentially expressed in PK-15 from the PCV2-infected group compared to the uninfected control group. A total of 196 cellular proteins in PK-15 that were significantly altered at different time periods post-infection were identified. These differentially expressed proteins were related to the biological processes of binding, cell structure, signal transduction, cell adhesion, etc. and their interactions. Moreover, some of these proteins were further confirmed by Western blot. The high number of differentially expressed proteins identified should be very useful in elucidating the mechanism of replication and pathogenesis of PCV2 in the future.

Marek's disease virus may interfere with T cell immunity by TLR3 signals

Marek's disease virus (MDV) is a highly oncogenic alpha-herpesvirus that causes T cell immune suppression and malignant lymphomas in chickens. Toll-like receptor (TLR) plays a dominant role in antiviral T cell immunity. However, it is unclear whether MDV induced T cell immunity is associated with TLR-mediated immunity. In this study, the expression of 28 host genes that are involved in TLR-mediated immunity and MHC-medicated T cell immunity was evaluated in chicken thymus at 7, 14, 21 and 28 days post-infection (dpi). Our results demonstrated that 24 host immune-related genes were upregulated during MDV infection at 7 dpi; however, the expression of most of these genes decreased at 21 and 28 dpi. Notably, a positive correlation was found between the down-regulation of CD4, CD8 and TLR3 signals but not the MyD88-dependent TLR pathway. The present study expanded our knowledge of host immune responses against MDV infection and our results might provide a clue that MDV may interfere with T cell immune response through TLR3 signals.

Proteomic analysis of epithelioma papulosum cyprini cells infected with spring viremia of carp virus

Spring viremia of carp (SVC), caused by spring viremia of carp virus (SVCV) is an important disease due to its drastic effects on carp fisheries in many countries. To better understand molecular responses to SVCV infection, two dimensional electrophoresis (2-DE) and MALDI-TOF/TOF were performed to investigate altered proteins in epithelioma papulosum cyprini cells (EPCs). Differentially expressed proteins in mock-infected EPCs and SVCV-infected EPCs were compared. A total of 54 differentially expressed spots were successfully identified (33 up-regulated spots and 21 down-regulated spots) which include cytoskeleton proteins, macromolecular biosynthesis-associated proteins, stress response proteins, signal transduction proteins, energy metabolism, and ubiquitin proteasome pathway-associated proteins. Moreover, 7 corresponding genes of the differentially expressed proteins were quantified using real time RT-PCR to examine their transcriptional profiles. The presence of four selected cellular proteins (beta-actin, gamma1-actin, heat shock cognate 71 kDa protein and annexin A2) associated with the spring viremia of carp virus (SVCV) particles was validated by Western blot assay. This study provides dynamic and useful protein-related information to further understand the underlying pathogenesis of SVCV infection.

Proteome dynamics in primary target organ of infectious bursal disease virus

Viruses induce dramatic changes in target tissue during pathogenesis, including host cellular responses that either limit or support the pathogen. The infectious bursal disease virus (IBDV) targets primarily the bursa of Fabricius (BF) of chickens, causing severe immunodeficiency. Here, we characterized the cellular proteome changes of the BF caused by IBDV replication in vivo using 2DE followed MALDI-TOF MS identification. Comparative analysis of multiple 2DE gels revealed that the majority of protein expression changes appeared between 24 and 96 h after IBDV infection. MS identified 54 altered cell proteins, 12 of which were notably upregulated by IBDV infection. Meanwhile, the other 42 cellular proteins were considerably suppressed by IBDV infection and are involved in protein degradation, energy metabolism, stress response, host macromolecular biosynthesis, and transport process. The upregulation of β-actin and downregulation of dynamin during IBDV infection were also confirmed by Western blot and immunofluorescence analysis. These altered protein expressions provide a response profile of chicken BF to virulent IBDV infection. Further functional study on these altered proteins may lead to better understanding of pathogenic mechanisms of virulent IBDV infection and to new potential therapeutic targets.

Analysis of protein expression profiles in the thymus of chickens infected with Marek's disease virus

BACKGROUND

Marek's disease virus (MDV) is a highly cell-associated oncogenic α-herpesvirus that causes a disease characterised by T-cell lymphomas. The pathogenesis, or the nature of the interaction of the virus and the host, in the thymus are still unclear.

RESULTS

In this study, we identified 119 differentially expressed proteins using two-dimensional electrophoresis and mass spectrometry from the thymuses of chickens infected with the RB1B strain of MDV. These differentially expressed proteins were found mainly at 21, 28 and 35 days post-infection. More than 20 of the differentially expressed proteins were directly associated with immunity, apoptosis, tumour development and viral infection and replication. Five of these proteins, ANXA1, MIF, NPM1, OP18 and VIM, were further confirmed using real-time PCR. The functional associations and roles in oncogenesis of these proteins are discussed.

CONCLUSIONS

This work provides a proteomic profiling of host responses to MDV in the thymus of chickens and further characterises proteins related to the mechanisms of MDV oncogenesis and pathogenesis.

Deciphering novel host-herpesvirus interactions by virion proteomics

Over the years, a vast array of information concerning the interactions of viruses with their hosts has been collected. However, recent advances in proteomics and other system biology techniques suggest these interactions are far more complex than anticipated. One particularly interesting and novel aspect is the analysis of cellular proteins incorporated into mature virions. Though sometimes considered purification contaminants in the past, their repeated detection by different laboratories suggests that a number of these proteins are bona fide viral components, some of which likely contribute to the viral life cycles. The present mini review focuses on cellular proteins detected in herpesviruses. It highlights the common cellular functions of these proteins, their potential implications for host–pathogen interactions, discusses technical limitations, the need for complementing methods and probes potential future research avenues.

Proteomic analysis of zebrafish (Danio rerio) infected with infectious spleen and kidney necrosis virus

Iridovirus infections remain a severe problem in aquaculture industries worldwide. Infectious spleen and kidney necrosis virus (ISKNV), the type species of the genus Megalocytovirus in the family Iridoviridae, has caused significant economic losses among freshwater fish in different Asian countries. To investigate the molecular mechanism of iridoviral pathogenesis, we analyzed the differential proteome from the spleen of ISKNV-infected zebrafish through two-dimensional gel electrophoresis (2-DE). Mass spectrometry revealed 35 altered cellular protein spots, including 15 upregulated proteins and 20 downregulated proteins at five days post-infection. The altered host proteins were classified into 13 categories based on their biological processes: cytoskeletal protein, stress response, lipoprotein metabolism, ubiquitin-proteasome pathway, carbohydrate metabolism, signal transduction, proteolysis, ion binding, transport, metabolic process, catabolic process, biosynthesis, and oxidation reduction. Moreover, 14 corresponding genes of the differentially expressed proteins were validated by RT-PCR. Western blot analysis further demonstrated the changes in α-tubulin, β-actin, HSC70, and major capsid protein (MCP) during infection. β-Actin was selected for further study via co-immunoprecipitation analyses, which confirmed that the cellular β-actin interacts with the MCP protein of ISKNV in the infected zebrafish. These findings provide insight into the interactions between iridoviruses (especially ISKNV) and host, as well as the mechanism and pathogenesis of ISKNV infections.

Proteomic analysis of chicken embryonic trachea and kidney tissues after infection in ovo by avian infectious bronchitis coronavirus

Background

Avian infectious bronchitis (IB) is one of the most serious diseases of economic importance in chickens; it is caused by the avian infectious coronavirus (IBV). Information remains limited about the comparative protein expression profiles of chicken embryonic tissues in response to IBV infection in ovo. In this study, we analyzed the changes of protein expression in trachea and kidney tissues from chicken embryos, following IBV infection in ovo, using two-dimensional gel electrophoresis (2-DE) coupled with matrix-assisted laser desorption/ionization time-of-flight tandem mass spectrometry (MALDI-TOF-TOF MS).

Results

17 differentially expressed proteins from tracheal tissues and 19 differentially expressed proteins from kidney tissues were identified. These proteins mostly related to the cytoskeleton, binding of calcium ions, the stress response, anti-oxidative, and macromolecular metabolism. Some of these altered proteins were confirmed further at the mRNA level using real-time RT-PCR. Moreover, western blotting analysis further confirmed the changes of annexin A5 and HSPB1 during IBV infection.

Conclusions

To the best of our knowledge, we have performed the first analysis of the proteomic changes in chicken embryonic trachea and kidney tissues during IBV infection in ovo. The data obtained should facilitate a better understanding of the pathogenesis of IBV infection.

Proteomic analysis of host responses to Marek's disease virus infection in spleens of genetically resistant and susceptible chickens

Resistance to Marek's disease (MD) in chickens is genetically regulated and there are lines of chickens with differential susceptibility or resistance to this disease. The present study was designed to study comparative changes in the spleen proteomes of MD-susceptible B19 and MD-resistant B21 chickens in response to MDV infection. Spleen proteomes were examined at 4, 7, 14 and 21 days post-infection (d.p.i.) using two-dimensional gel electrophoresis and subsequently the protein spots were identified by one-dimensional liquid chromatography electrospray ionization tandem mass spectrometry (1D LC ESI MS/MS). On average, there were 520+/-27 distinct protein spots on each gel and 1.6+/-0.7% of the spots differed quantitatively in their expression (p< or =0.05 and fold change > or =2) between infected B19 and B21 chickens. There was one spot at 4d.p.i. and three spots each at the rest of the time points, which had a qualitative difference in expression. Most of the differentially expressed proteins at 4 and 7d.p.i. displayed increased expression in B21 chickens; conversely the differentially expressed proteins at 14 and 21d.p.i. showed an increase in expression in B19 chickens. The differentially expressed proteins identified in the present study included antioxidants, molecular chaperones, proteins involved in the formation of cytoskeleton, protein degradation and antigen presentation, signal transduction, protein translation and elongation, RNA processing and cell proliferation. These findings shed light on some of the underlying processes of genetic resistance or susceptibility to MD.

Marek's disease virus influences the expression of genes associated with IFN-gamma-inducible MHC class II expression

Chickens infected with Marek's disease virus (MDV) become lifelong carriers regardless of their susceptibility to clinical disease. Therefore various viral immune-evasive mechanisms must play a role in MDV-host interactions. MDV has previously been shown to influence the expression of major histocompatibility complex (MHC) class II molecules. However, little is known about the underlying mechanisms of this phenomenon. In the present study, we studied the effect of MDV infection on the expression of several genes associated with IFN-gamma-inducible MHC class II expression at 4, 7, 14, and 21 days post-infection (dpi). There was a significant (p Collapse

Key Words Collapse

MESH Headings

• Animals
• Chickens/virology
• Gene Expression Profiling
• Genes, MHC Class II
• Immunologic Surveillance/genetics
• Interferon Regulatory Factor-1/genetics
• Interferon-gamma/immunology
• Mardivirus/immunology
• Marek Disease/genetics
• Marek Disease/immunology
• Nuclear Proteins/genetics
• Poultry Diseases/genetics
• Poultry Diseases/immunology
• Receptors, Interferon/genetics
• STAT1 Transcription Factor/metabolism
• Signal Transduction
• Time Factors
• Trans-Activators/genetics
• Interferon gamma Receptor

Collapse

Grants Collapse

Affiliation(s)

Niroshan Thanthrige-Don Department of Pathobiology, University of Guelph, Guelph, Ontario, Canada
Leah R Read
Mohamed Faizal Abdul-Careem
Hakimeh Mohammadi
Amirul I Mallick
Shayan Sharif

Collapse