Differential Transcriptome Analysis of CD4+ T Cells of Chickens Induced By Marek's Disease Virus Challenge

Marek’s disease (MD) is a T cell lymphoma of chickens induced by Marek’s disease virus (MDV). MD causes severe economic loss. MDV life cycle can be divided into four phases, including the third phase from 18 to 28 days post infection (dpi) known as late cytolytic infection, which mainly occurs in CD4+CD8- T cells and is accompanied by the presence of tumors in various organs in highly susceptible chickens. This study was aimed to explore differentially expressed transcriptomic patterns in CD4+ T cells of MD resistant and susceptible (F₀) lines of chickens as well as two reciprocal crosses (F₁) of the two lines between infected and non-infected groups at 21 dpi. A few of differentially expressed (DE) genes were identified in the MD resistant line 6₃ (FDR <= 0.1, |logFC| > =1), while 93 genes were detected in susceptible line 7₂. In contrast, 217 DE genes were discovered in one of the reciprocal crosses and 694 were obtained for the other cross. Interestingly, there were 51 DE genes in common between the two generation groups, in which 24 genes involving in the MHC class II antigen and cytotoxic T-lymphocyte-associated processes remained high expression in non-infected birds through F₀ to F₁ generations, and 11 genes expressed higher levels in infected birds across two generations. Hence, these MD-resistant candidate genes are of interest for further exploration in functions, which may help to understand the mechanism on MD resistance.