Dynamic Changes in the Splenic Transcriptome of Chickens during the Early Infection and Progress of Marek’s Disease

Abstract

Gallid alphaherpesvirus 2 (GaHV2) is an oncogenic avian herpesvirus inducing Marek’s disease (MD) and rapid-onset T-cell lymphomas. To reveal molecular events in MD pathogenesis and tumorigenesis, the dynamic splenic transcriptome of GaHV2-infected chickens during early infection and pathogenic phases has been determined utilizing RNA-seq. Based on the significant differentially expressed genes (DEGs), analysis of gene ontology, KEGG pathway and protein-protein interaction network has demonstrated that the molecular events happening during GaHV2 infection are highly relevant to the disease course. In the ‘Cornell Model’ description of MD, innate immune responses and inflammatory responses were established at early cytolytic phase but persisted until lymphoma formation. Humoral immunity in contrast began to play a role firstly in the intestinal system and started at late cytolytic phase. Neurological damage caused by GaHV2 is first seen in early cytolytic phase and is then sustained throughout the following phases over a long time period. During the proliferative phase many pathways associated with transcription and/or translation were significantly enriched, reflecting the cell transformation and lymphoma formation. Our work provides an overall view of host responses to GaHV2 infection and offers a meaningful basis for further studies of MD biology.

Transcriptional Profiles Associated with Marek’s Disease Virus in Bursa and Spleen Lymphocytes Reveal Contrasting Immune Responses during Early Cytolytic Infection

“…MDV infects and causes alterations in proliferation and activation of B cells. Studies have shown that MDV affects the disease outcome by merely altering or controlling the host cellular machinery in order to facilitate its replication [40]. Meanwhile, it is the innate immune response that is chiefly involved in the battle against invading MDV.…”

Endogenous retroviruses transcriptomes in response to four avian pathogenic microorganisms infection in chicken

“…Expression of ChERVs in ALV-J, AIV, MDV and APEC infected samples and corresponding uninfected samples. RNA-seq data from ALV-J (A) [23], AIV (C) [24], MDV (E) [25] and APECinfected chicken (F) [26] and corresponding uninfected controls were aligned using TopHat and transcripts were constructed using Cufflinks. The number of fragments per kilobase per Expression of ChERVs in ALV-J, AIV, MDV and APEC infected samples and corresponding uninfected samples.…”

“…The published splenic transcriptome raw data of MDV-infected samples and uninfected samples at 14 dpi were selected for ChERVs transcriptome analysis [25]. Two cDNA libraries of MDV-infected and uninfected samples were designated as CH-14dpi (SRA:SRX2425016) and CH-14d (SRA:SRX2425017).…”

“…To obtain global view of ChERVs expression after pathogenic microbial infection in chicken, four published transcriptome raw data about ALV-J, AIV, MDV and APEC infection were used to match Gallus_gallus-5.0 genome for deep analysis [23][24][25][26]. The analysis resulted in the identification of 258 (59.4%) ChERVs that were transcribed in ALV-J-infected spleens or their controls ( Fig.…”

“…In all cases, it is relatively easy to explore the function of ERV by analyzing the expression level of ERVs. Thus, ChERV transcriptomes were analyzed after ALV-J, AIV, MDV and APEC infection in chicken using the published data [23][24][25][26]. We provide an overview of the expression of ChERVs in the chicken tissues of ALV-J, AIV, MDV and APEC infection.…”