DNA Methylation and Regulation of the CD8A after Duck Hepatitis Virus Type 1 Infection

Abstract

BackgroundCluster of differentiation 8 (CD8) is expressed in cytotoxic T cells, where it functions as a co-receptor for the T-cell receptor by binding to major histocompatibility complex class I (MHCI) proteins, which present peptides on the cell surface. CD8A is critical for cell-mediated immune defense and T-cell development. CD8A transcription is controlled by several cis-acting elements and trans-acting elements and is also regulated by DNA methylation. However, the epigenetic regulation of CD8A in the duck and its relationship with virus infection are still unclear.ResultsWe investigated the epigenetic transcriptional regulatory mechanisms, such as DNA methylation, for the expression of the CD8A and further evaluated the contribution of such epigenetic regulatory mechanisms to DHV-I infection in the duck. Real-time quantitative polymerase chain reaction (RT-qPCR) revealed the highest level of CD8A expression to be in the thymus, followed by the lungs, spleen, and liver, and the levels of CD8A expression were very low in the kidney, cerebrum, cerebellum, and muscle in the duck. RT-qPCR also demonstrated that the CD8A mRNA was down-regulated significantly in morbid ducklings treated with DHV-1 and up-regulated significantly in non-morbid ducklings in all the tissues tested. In addition, hypermethylation of CD8A was detected in the morbid ducklings, whereas relatively low methylation of CD8A was evident in the non-morbid ducklings. The CD8A mRNA level was negatively associated with the CpG methylation level of CD8A and global methylation status.ConclusionsWe concluded that the mRNA level of the CD8A was negatively associated with the CpG methylation level of CD8A and global methylation status in the duck, suggesting that the hypermethylation of CD8A may be associated with DHV-1 infection. The first two CpG sites of the CD8A promoter region could be considered as epigenetic biomarkers for resistance breeding against duckling hepatitis disease in the duck.

Dynamic Expression Pattern of SERPINA1 Gene from Duck (Anas platyrhynchos)

“…Injection dose and injection method are consistent with our earlier trials [18]. Besides, the ducklings after the infection showed the typical symptoms of hepatitis by carrying the DHV-1 virus, and the relative results have been published [17]. In this study, at various times (0, 4, 8, 12, 24, 36, 48, 72, and 96 hours post-infection (h.p.i), three birds in each group were euthanized by injecting sodium pentobarbital (150 mg/kg) and killed by exsanguination.…”

“…RT-PCR was used to make sure that the ducklings had not been exposed to DHV previous to our study [16]. Then, the ducklings were randomly divided into three groups, the 40 ducklings were injected with 0.4 mL of DHV-1(ELD50 10 −4.6 /0.2ml) according to our earlier trials [17, 18], and the 40 ducklings were injected with 0.4 mL of poly I: C (0.5 mg/mL, Invivogen, California, USA), another 40 treated with normal saline (as uninfected controls). Injection dose and injection method are consistent with our earlier trials [18].…”

“…DHV-1 is a small RNA virus causing high mortality in ducks (Anas platyrhynchos), especially in younger ducklings. In order to reduce the effect of DHV-1, a large number of studies have been reported on this virus [8–14]. In our previous study, we identified differentially expressed sequence tags (ESTs) of SERPINA1 using a suppression subtractive hybridization (SSH) cDNA library of 3-day-old ducklings treated with DHV-1 [15].…”

Ganoderma lucidum polysaccharide improves rat DSS-induced colitis by altering cecal microbiota and gene expression of colonic epithelial cells

“…Among the six upregulated genes, Lck was considered to activate and mature T lymphocytes (44). Cd8a was also crucial for the production of T lymphocytes, while Cd3e was the essential component of the T cell receptor (TCR) complex for antigens (45, 46). Therefore, these four genes may improve the immunity of the colon in rats.…”

Evaluation of the Protective Efficacy of Poly I:C as an Adjuvant for H9N2 Subtype Avian Influenza Inactivated Vaccine and Its Mechanism of Action in Ducks

“…To validate assays, each sample was tested in triplicate. PCR primers for IFN-alpha (IFN-α) and CD8α were as described previously [ 26 , 27 ]. Interleukin 2 (IL-2), IL-6, interferon-gamma (IFN-γ), β-Actin, CD4, major histocompatibility complex (MHC) Class I (MHC-I) and II (MHC-II) were designed using Primer 3 software based on published sequences.…”