TCRs from (A) a peptide-MHC tetramer-enriched sub-repertoire, (B) a MIRA peptide stimulation-enriched sub-repertoire, or (C) an umbilical cord blood unenriched repertoire. Within each sub-repertoire, an empirical cumulative distribution function (ECDF) was estimated for each TCR (one line) acting as the centroid of a neighborhood over a range of distance radii (x-axis). Each ECDF shows the proportion of TCRs within the sub-repertoire found within the indicated radius from the centroid TCR. ECDF color corresponds to the number of amino acids in the TCR CDR3 loop. ECDF curves were randomly shifted by <1 unit along the x-axis to reduce overplotting. Vertical ECDF lines at 10–6 indicate no similar TCRs at or below that radius. Percentage of TCRs with an ECDF proportion < 10–3 (bottom panels), indicates the percentage of TCRs without, or with very few biochemically similar neighbors at the given radius.