Comprehensive Transcriptomic Comparison between Porcine CD8^- and CD8⁺ Gamma Delta T Cells Revealed Distinct Immune...

Area of Science:

• Immunology
• T cell biology
• Swine research

Background:

• Gamma delta (γδ) T cells play a vital role in innate and adaptive immunity.
• Understanding the functional mechanisms of γδ T cell subsets, particularly CD8+ and CD8-, is essential for advancing swine immunology.
• Previous research has not fully elucidated the specific gene expression profiles differentiating these subsets in pigs.

Purpose of the Study:

• To comprehensively understand the functional mechanisms of CD8+ and CD8- gamma delta (γδ) T cell subsets in pigs.
• To identify differentially expressed genes (DEGs) between CD8+ and CD8- γδ T cells at different post-weaning stages.
• To explore the enriched signaling pathways associated with these gene expression differences.

Main Methods:

• RNA-sequencing analysis was performed on γδ T cells from weaned pigs at 38-day-old (D10) and 56-day-old (D28).
• γδ T cells were isolated from bronchial lymph node tissues and sorted into CD8+ and CD8- groups.
• Differentially expressed genes (DEGs) were identified and analyzed for pathway enrichment.

Main Results:

• 1699 DEGs were identified between CD8+ and CD8- groups at D10, and 1784 DEGs at D28.
• 646 upregulated and 561 downregulated DEGs were common to both time points.
• Upregulated DEGs were enriched in cytokine-cytokine receptor interaction and T cell receptor (TCR) signaling pathways; downregulated DEGs were enriched in the B cell receptor signaling pathway.

Conclusions:

• The study provides foundational data for understanding γδ T cell mechanisms in pigs, highlighting the importance of CD8 expression.
• Enriched pathways suggest a role for chemokine-related genes, interferon gamma, and CD40 ligand in γδ T cell inter-regulation.
• Further research is needed to investigate dynamic changes in γδ T cells during pathogenic infections.