Figure 10. T cell receptor complementarity-determining region 3 sequences from salivary gland CD4⁺ T cells are significantly enriched in degree of sequence relatedness compared with healthy peripheral blood CD4⁺ T cells.

T cell receptor (TCR) deep-sequencing data from two healthy DR3/DQ2⁺ control subjects were sampled 2,000 times, and pairwise BLAST similarity scores were obtained. These were used to generate hypothetical distributions of the percentage of comparisons having scores ≥50% of the maximum value (gray). The dashed lines indicate the percentage of salivary gland (SG) CD4⁺ memory T cell TCR sequences having BLAST scores ≥50% of the maximum value in the actual SG TCR sequence data. Significance was calculated from the cumulative distribution function of the estimated hypothetical distribution (P = 4.1 × 10^–6 and P = 3.4 × 10^–19 goodness-of-fit tests for the TCRα and TCRβ comparisons, respectively).