Search

The porcine reproductive and respiratory syndrome (PRRS) is a devastating viral disease affecting swine production, health and welfare throughout the world. A synergistic action of the innate and the adaptive immune system of the host is essential for mounting a durable protective immunity through vaccination. Therefore, the current study aimed to investigate the transcriptome profiles of peripheral blood mononuclear cells (PBMCs) to characterize the innate and the adaptive immune response to PRRS Virus (PRRSV) vaccination in Pietrain pigs. The Affymetrix gene chip porcine gene 1.0 ST array was used for the transcriptome profiling of PBMCs collected at immediately before (D0), at one (D1) and 28 days (D28) post PRRSV vaccination with three biological replications. With FDR <0.05 and log2 fold change ±1.5 as cutoff criteria, 295 and 115 transcripts were found to be differentially expressed in PBMCs during the stage of innate and adaptive response, respectively. The microarray expression results were technically validated by qRT-PCR. The gene ontology terms such as viral life cycle, regulation of lymphocyte activation, cytokine activity and inflammatory response were enriched during the innate immunity; cytolysis, T cell mediated cytotoxicity, immunoglobulin production were enriched during adaptive immunity to PRRSV vaccination. Significant enrichment of cytokine-cytokine receptor interaction, signaling by interleukins, signaling by the B cell receptor (BCR), viral mRNA translation, IFN-gamma pathway and AP-1 transcription factor network pathways were indicating the involvement of altered genes in the antiviral defense. Network analysis revealed that four network modules were functionally involved with the transcriptional network of innate immunity, and five modules were linked to adaptive immunity in PBMCs. The innate immune transcriptional network was found to be regulated by LCK, STAT3, ATP5B, UBB and RSP17. While TGFß1, IL7R, RAD21, SP1 and GZMB are likely to be predictive for the adaptive immune transcriptional response to PRRSV vaccine in PBMCs. Results of the current immunogenomics study advances our understanding of PRRS in term of host-vaccine interaction, and thereby contribute to design a rationale for disease control strategy.

An association study between polymorphisms of six genes and boar taint related compounds androstenone, skatole and indole was performed in a boar population (n=370). Significant association (P<0.05) was detected for SNP of FMO5 (g.494A>G) with all boar taint compounds, SNP of CYP21 (g.3911T>C) with skatole and indole, and SNP of ESR1 (g.672C>T) with androstenone and indole. mRNA expression of CYP21 and ESR1 was higher in CAB (castrated boar) compared to non-castrated boars; whereas, the expression of FMO5 and ESR1 was higher in LBT (low boar taint) compared to HBT (high boar taint) in liver tissue. FMO5, CYP21 and ESR1 proteins were less detectable in HBT compared with LBT and CAB in liver tissues. These findings suggest that FMO5, CYP21 and ESR1 gene variants might have effects on the boar taint compounds., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of the study was to investigate single nucleotide polymorphisms (SNPs) and expression of SOX-6 to support its candidacy for growth, carcass, and meat quality traits in pigs. The first SNP, rs81358375, was associated with pH 45 min post mortem in loin (pH1L), the thickness of backfat and side fat, and carcass length in Pietrain (Pi) population, and related with backfat thickness and daily gain in Duroc × Pietrain F2 (DuPi) population. The other SNP, rs321666676, was associated with meat colour in Pi population. In DuPi population, the protein, not mRNA, level of SOX-6 in high pH1L pigs was significantly less abundant compared with low pH1L pigs, where microRNAs targeting SOX-6 were also differently regulated. This paper shows that SOX-6 could be a potential candidate gene for porcine growth, carcass, and meat quality traits based on genetic association and gene expression., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The aim of the present study was to investigate the age-related production variation of T helper (Th)-type cytokines (IL-2, IL-4, IFN-γ and IL-10), granulocyte macrophage-colony stimulating factor (GM-CSF) and nitric oxide (NO) by lipopolysaccharide (LPS)-stimulated porcine alveolar macrophages (AMs) in a time-dependent manner. For this purpose, AMs were isolated from 5-days (newborn), 40-days (post-weaned) and 120-days (young) old pigs. Cells were incubated for 24h in the absence or presence of increasing concentrations of LPS (0.0, 0.01, 1.0, 5.0 and 10.0 μg/mL). IL-10, IFN-γ and GM-CSF mRNA expression was upregulated in a dose-dependent manner for all age groups (P<0.05). Age-related differences included a significantly increased IL-10 mRNA and protein production in newborn piglets compared to post-weaned and young pigs. IL-10 production pattern was similar with a higher peak between 12 and 36 h post-induction in all age groups. In contrast, IFN-γ mRNA and protein level was significantly elevated in young pigs 12h and 24h post-induction, respectively, while the time course production of IFN-γ was mostly consistent in newborn and post-weaned piglets. GM-CSF mRNA expression was significantly lower in newborn piglets than in post-weaned and young pigs. The kinetic of GM-CSF expression peaked at 12h in young and post-weaned pigs and at 24h in newborn piglets. IL-4 mRNA levels were very low and no apparent change of IL-2 expression was observed following LPS stimulation in all age groups. Only very low levels of NO were detected in the cell supernatants of young pigs. Collectively, these studies suggest age-related differences in time-dependent production of IL-10, IFN-γ and GM-CSF by porcine AMs with potential immunoregulatory consequences to be explored further., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The aim was to study the expression pattern of the porcine TLR family (TLR1-10) genes in gut-associated lymphoid tissues (GALT) of varying ages. A total of nine clinically healthy pigs of three ages group (1 day, 2 months and 5 months old) were selected for this experiment (three pigs in each group). Tissues from intestinal mucosa in stomach, duodenum, jejunum and ileum and mesenteric lymph node (MLN) were used. mRNA expression of TLRs (1-10) was detectable in all tissues and TLR3 showed the highest mRNA abundance among TLRs. TLR3 expression in stomach, and TLR1 and TLR6 expression in MLN were higher in adult than newborn pigs. The western blot results of TLR2, 3 and 9 in some cases, did not coincide with the mRNA expression results. The protein localization of TLR2, 3 and 9 showed that TLR expressing cells were abundant in the lamina propria, Peyer's patches in intestine, and around and within the lymphoid follicles in the MLN. This expressions study sheds the first light on the expression patterns of all TLR genes in GALT at different ages of pigs., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Male fertility is impaired through the lack of ESR1 (Estrogen Receptor 1) but little is known about the ESR1 roles in boar spermatogenesis and fertility. Therefore, this research was aimed at investigating the association with sperm quality and boar fertility traits in a total of 300 boars both from purebred Pietrain and Pietrain × Hampshire crosses. A SNP in coding region of ESR1g.672C>T in exon 1 was associated with sperm motility (P<0.05) and plasma droplet rate (P<0.01) while the polymorphism in non-coding region of ESR1g.35756T>C in inton 1 was associated with non-return rate (P<0.05). Furthermore, to analyse the mRNA and protein expression of ESR1 in boar reproductive tissues, a total of six boars were divided into two groups [Group I (G-I) and Group II (G-II)], where G-I had relatively better sperm quality. ESR1 expression was higher in tissues collected from G-I boars than those of collected from G-II boars, and the difference in mRNA expression was significant (P<0.01) in head of epididymis. The ESR1 protein expression results from western blot coincided with the results of qRT-PCR. The ESR1 protein localization observed a strong staining in the cytoplasm of Sertoli cell in the testis, in the epithelial cells in head and tail of epididymis, in smooth muscle in tail of epididymis, and in the post acrosomal region and tail of the spermatozoa. These results will improve the understanding of the functions of the ESR1 in spermatogenesis within the reproductive tract and will shed light on ESR1 as a candidate in the selection of boar with good sperm quality and fertility., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Background: Serum lipids are associated with many serious cardiovascular diseases and obesity problems. Many quantitative trait loci (QTL) have been reported in the pig mostly for performance traits but very few for the serum lipid traits. In contrast, remarkable numbers of QTL are mapped for serum lipids in humans and mice. Therefore, the objective of this research was to investigate the chromosomal regions influencing the serum level of the total cholesterol (CT), triglyceride (TG), high density protein cholesterol (HDL) and low density protein cholesterol (LDL) in pigs. For this purpose, a total of 330 animals from a Duroc × Pietrain F2 resource population were phenotyped for serum lipids using ELISA and were genotyped by using 122 microsatellite markers covering all porcine autosomes for QTL study in QTL Express. Blood sampling was performed at approximately 175 days before slaughter of the pig., Results: Most of the traits were correlated with each other and were influenced by average daily gain, slaughter date and age. A total of 18 QTL including three QTL with imprinting effect were identified on 11 different porcine autosomes. Most of the QTL reached to 5% chromosome-wide (CW) level significance including a QTL at 5% experiment-wide (GW) and a QTL at 1% GW level significance. Of these QTL four were identified for both the CT and LDL and two QTL were identified for both the TG and LDL. Moreover, three chromosomal regions were detected for the HDL/LDL ratio in this study. One QTL for HDL on SSC2 and two QTL for TG on SSC11 and 17 were detected with imprinting effect. The highly significant QTL (1% GW) was detected for LDL at 82 cM on SSC1, whereas significant QTL (5% GW) was identified for HDL/LDL on SSC1 at 87 cM. Chromosomal regions with pleiotropic effects were detected for correlated traits on SSC1, 7 and 12. Most of the QTL identified for serum lipid traits correspond with the previously reported QTL for similar traits in other mammals. Two novel QTL on SSC16 for HDL and HDL/LDL ratio and an imprinted QTL on SSS17 for TG were detected in the pig for the first time., Conclusion: The newly identified QTL are potentially involved in lipid metabolism. The results of this work shed new light on the genetic background of serum lipid concentrations and these findings will be helpful to identify candidate genes in these QTL regions related to lipid metabolism and serum lipid concentrations in pigs.

Cluster-of-differentiation antigen 9 (CD9) gene expressed in the male germ line stem cells is crucial for sperm-egg fusion, and was therefore selected as candidate gene for boar semen quality. The association of CD9 with boar sperm quality and fertility trait was analyzed using a total of 340 boars both from purebred Pietrain and Pietrain×Hampshire crosses. A single nucleotide polymorphism (g.358A>T) in intron 6 was significantly associated with sperm motility (MOT) (P<0.001), plasma droplet rate (PDR) (P<0.001) and abnormal spermatozoa rate (ASR) (P<0.01). Boars were divided into two groups with group 1 (G-I) boars having a higher SCON and SMOT, lower SVOL (sperm volume) and group 2 (G-II) having a lower SCON and SMOT, higher SVOL. The mRNA and protein expression levels were evaluated in reproductive, non-reproductive tissues and spermatozoa from G-I and G-II animals by using quantitative real-time PCR and western blotting. When both reproductive and non-reproductive tissues were examined, highest mRNA was expressed in prostate gland, then in the body of the epididymis, vas deferens and tail of the epididymis. In case of reproductive tissues, CD9 expression was higher in tissues and spermatozoa collected from G-I boars than those collected from G-II boars. The mRNA expression was significantly different (P<0.05) in body of epididymis from G-I and G-II boars. The CD9 protein expression results from western blot were coincided with the results of qRT-PCR. Moreover, CD9 protein localization in Leydig cells, Sertoli cells, epithelial cells and spermatozoa was remarkable which indicated the important role of CD9 in spermatogenesis process. By using mRNA and protein expression profiles, it could be shown that CD9 plays a crucial role during sperm development, especially within the epididymis where the maturation of the sperm, a key process for the sperm quality and motility takes place. These results will improve the understanding of the functions of the CD9 in spermatogenesis within the reproductive tracts and will shed light on CD9 as a candidate gene in the selection of good sperm quality boars., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The aim of the present study was to detect quantitative trait loci (QTL) for innate and adaptive immunity in pigs. For this purpose, a Duroc x Pietrain F(2) resource population (DUPI) with 319 offspring was used to map QTL for the immune traits blood antibodies and interferon-gamma using 122 microsatellites covering all autosomes. Antibodies response to Mycoplasma hyopneumoniae and tetanus toxoid vaccine and the interferon-gamma (IFNG) serum concentration were measured at three different time points and were used as phenotypes. The differences of antibodies and interferon concentration between different time points were also used for the linkage mapping. Line-cross and imprinting QTL analysis, including two-QTL, were performed using QTL Express. A total of 30 QTL (12, 6, and 12 for mycoplasma, tetanus antibody, and IFNG, respectively) were identified at the 5% chromosome-wide-level significant, of which 28 were detected by line-cross and 2 by imprinting model. In addition, two QTL were identified on chromosome 5 using the two-QTL approach where both loci were in repulsion phase. Most QTL were detected on pig chromosomes 2, 5, 11, and 18. Antibodies were increased over time and immune traits were found to be affected by sex, litter size, parity, and month of birth. The results demonstrated that antibody and IFNG concentration are influenced by multiple chromosomal areas. The flanking markers of the QTL identified for IFNG on SSC5 did incorporate the position of the porcine IFNG gene. The detected QTL will allow further research in these QTL regions for candidate genes and their utilization in selection to improve the immune response and disease resistance in pig.

This study examined the association, promoter methylation of Interferon alpha-inducible protein 6 (IFI6) gene, and their effects on mRNA expression and meat quality traits in pig. Muscle samples (n=300) were randomly collected from the Longissimus thoracis et lumborum (LTL) to determine meat quality traits including drip loss, thawing loss, cooking loss, meat pH [at 45 minutes (pH45min) and at 24 hours (pH24h) post-mortem], shear force (for tenderness), and lightness (L*) in pigs. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Muscle samples (5 per group) with divergent meat pH (low vs high) were selected for promoter methylation study using bisulfate and pyrosequencing. Muscle samples from animals (5 per group) with divergent phenotypes (low vs high meat pH and low vs high drip loss) were used for mRNA expression study by quantitative real-time polymerase chain reaction (qRT-PCR). Results showed that a polymorphism in IFI6 gene (g.370A>G) was significantly (P < 0.01) associated with meat pH24h. Furthermore, four CpG regions were identified in IFI6 promoter, of which DNA methylation in a CG site was higher in low meat pH24h group compared to high meat pH24h group (P < 0.05). The mRNA expression of IFI6 gene was significantly (P < 0.01) downregulated in low meat pH24h group than high meat pH24h group. This result postulated that high DNA methylation at CG site in the promoter region might downregulate the IFI6 gene expression, hence lower the muscle pH that might lead to higher drip loss and lower tenderness. Therefore, porcine IFI6 gene might be a potential candidate gene for meat quality trait in pig. Nevertheless, further research is needed to confirm the role of IFI6 gene in controlling meat quality traits in other commercial populations. This study analysed association of a SNP in IFI6 gene with meat quality traits, and promotor methylation and transcriptome expression of IFI6 gene in relation to meat pH. The result suggested that polymorphism affects meat pH. The high DNA methylation at a specific CG site in the IFI6 promoter is involved in IFI6 gene downregulation in low meat pH. [ABSTRACT FROM AUTHOR]

Porcine reproductive and respiratory syndrome (PRRS) is a devastating viral disease affecting the swine industry worldwide. Genetic variation in host immunity has been considered as one of the potential determinants to improve the immunocompetence, thereby resistance to PRRS. Therefore, the present study aimed to investigate the breed difference in innate immune response to PRRSV vaccination between German Landrace (DL) and Pietrain (Pi) pigs. We analyzed microarray-based transcriptome profiles of peripheral blood mononuclear cells (PBMCs) collected before (0 h) and 24 h after PRRSV vaccination from purebred DL and Pi pigs with three biological replicates. In total 4,269 transcripts were identified to be differentially expressed in PBMCs in at least any of four tested contrast pairs (i.e. DL-24h vs. DL-0h, Pi-24h vs. Pi-0h, DL-0h vs. Pi-0h and DL-24h vs. Pi-24h). The number of vaccine-induced differentially expressed genes (DEGs) was much higher (2,459) in DL pigs than that of Pi pigs (291). After 24 h of PRRSV vaccination, 1,046 genes were differentially expressed in PMBCs of DL pigs compared to that of Pi (DL-24h vs. Pi-24h), indicating the breed differences in vaccine responsiveness. The top biological pathways significantly affected by DEGs of both breeds were linked to immune response functions. The network enrichment analysis identified ADAM17, STAT1, MMS19, RPA2, BAD, UCHL5 and APC as potential regulatory genes for the functional network of PRRSV vaccine response specific for DL; while FOXO3, IRF2, ADRBK1, FHL3, PPP2CB and NCOA6 were found to be the most potential hubs of Pi specific transcriptome network. In conclusion, our data provided insights of breed-specific host transcriptome responses to PRRSV vaccination which might contribute in better understanding of PPRS resistance in pigs. [ABSTRACT FROM AUTHOR]

The porcine reproductive and respiratory syndrome (PRRS) is an infectious disease that leads to high financial and production losses in the global swine industry. The pathogenesis of this disease is dependent on a multitude of factors, and its control remains problematic. The immune system generally defends against infectious diseases, especially dendritic cells (DCs), which play a crucial role in the activation of the immune response after viral infections. However, the understanding of the immune response and the genetic impact on the immune response to PRRS virus (PRRSV) remains incomplete. In light of this, we investigated the regulation of the host immune response to PRRSV in porcine lung DCs using RNA-sequencing (RNA-Seq). Lung DCs from two different pig breeds (Pietrain and Duroc) were collected before (0 hours) and during various periods of infection (3, 6, 9, 12, and 24 hours post infection (hpi)). RNA-Seq analysis revealed a total of 20,396 predicted porcine genes, which included breed-specific differentially expressed immune genes. Pietrain and Duroc infected lung DCs showed opposite gene expression courses during the first time points post infection. Duroc lung DCs reacted more strongly and distinctly than Pietrain lung DCs during these periods (3, 6, 9, 12 hpi). Additionally, cluster analysis revealed time-dependent co-expressed groups of genes that were involved in immune-relevant pathways. Key clusters and pathways were identified, which help to explain the biological and functional background of lung DCs post PRRSV infection and suggest IL-1β1 as an important candidate gene. RNA-Seq was also used to characterize the viral replication of PRRSV for each breed. PRRSV was able to infect and to replicate differently in lung DCs between the two mentioned breeds. These results could be useful in investigations on immunity traits in pig breeding and enhancing the health of pigs. [ABSTRACT FROM AUTHOR]