Abstract
CD8 subunit alpha (CD8A) is an important gene in immunity and is involved in the functional regulation of T lymphocytes. However, the specific role and regulatory mechanism of CD8A in chicken T lymphocytes remain unknown. In this study, we overexpressed and interfered with CD8A in chicken T lymphocytes and found that interfering with CD8A expression inhibited the proliferation and induced the apoptosis of T lymphocytes and that the overexpression of CD8A promoted T lymphocyte activation. Additionally, transcriptomic and metabolomic analyses of chicken T lymphocytes with CD8A overexpression or interference were performed. The overexpression and interference of the CD8A gene caused widespread changes in gene and metabolite expression in chicken T cells. The results of the transcriptome analysis revealed that differentially expressed genes (DEGs) caused by altered expression of the CD8A gene were associated with multiple "neuroactive ligand-receptor interaction", "cell adhesion molecules", "calcium signaling pathway", etc. The metabolome analysis results revealed that different metabolites (DMs) caused by altered CD8A gene expression were associated with "Glutathione metabolism", "Arginine biosynthesis", "D-amino acid metabolism", etc. The combined transcriptional and metabolic analysis revealed one metabolically related pathway, "Glutathione metabolism". Our findings further revealed that interference and overexpression of CD8A plays a role in the metabolism of Glutathione. Thus, CD8A may be a critical regulator of "Glutathione metabolism" and may subsequently affect T-cell function in chickens. These results provide an important reference for further research on the effect of CD8A on the immune performance of chickens.