Cytokine gene expression in splenic CD4 and CD8 T cell subsets of genetically resistant and susceptible chickens infected with Marek's disease virus

摘要

T cells from the spleens of Bp##/Bp## and Bpop#/Bpop# chickens infected with MDV JM-16 strain were fractionated by flow cytometry at 4, 10, 21 days post infection (d.p.i.). The expression of cytokine and viral genes (meq and glycoprotein B (gB)) was measured by real-time RT-PCR. It was determined that CD4 and CD8 T cells had both become infected with Marek's disease virus (MDV) in both chicken lines. There was significantly higher expression of meq in CD4 T cells compared to CD8 T cells at 10 and 21 d.p.i. Furthermore, at 10 and 21 d.p.i., there was a tendency for higher expression of meq in both T cell subsets of Bp## chickens compared to those of Bpop# chickens. There were temporal changes in the expression of cytokines, interferon (IFN)-d, interleukin (IL)-18, IL-6, and IL-10, in various T cell subsets. Among these changes, there was an increase in IL-10 expression in both T cell subsets at different time points, especially in the susceptible line at 10 and 21 d.p.i. Our results indicate that cytokines could be differentially induced by MDV in CD4 and CD8 T cell subsets and that IL-10 may play a role in the modulation of immune response to MDV. However, an association between cytokine gene expression in T cell subsets and resistance or susceptibility to MD was not established.