T cell receptor usage of canine intraepithelial CD8αα⁺ and CD8αβ⁺ T cells. T cell receptor usage of IEL from small bowel of healthy adult Beagle showing an example of CD8αβ⁺ and CD8αα⁺ subset detection and analysis of their TCR expression (TCRαβ and TCRγδ) (A), and analysis of TCRαβ and TCRγδ expression in the CD8αβ⁺ (B) and the CD8αα⁺ (C) subsets. Numbers were normalized to CD8αβ⁺ cells (B) and CD8αα⁺ cells (C), respectively. Mean values ± SD of n = 4 are shown.