Regulation of apoptotic pathways in bovine γ/δ T cells

T lymphocytes bearing γ/δ TCRs are a major population of T cells in neonatal calves and discrete subsets of γ/δ T cells display tissue-specific accumulation and responsiveness to infection. To enhance our understanding of the immunobiology of γ/δ T cells, we characterized the gene expression profile of circulating bovine γ/δ T cells following stimulation with recombinant human IL-2 and ConA. Statistical analysis of microarray data identified 108 genes with significantly altered expression, including four genes associated with apoptosis. Real-time reverse transcription-PCR (RT-PCR) analysis of 15 genes related to apoptotic pathways showed that both the Fas-mediated and the mitochondrial apoptotic pathways were repressed in circulating bovine γ/δ T cells in response to mitogen activation, indicating that stimulated peripheral bovine γ/δ T cells are resistant to activation-induced apoptosis.