Figure 5. Examination of the CDRH3 and clonal diversity in the primary B-cell receptor (BCR) repertoires of humans, Kymice, and mice reveal comparable diversity on a repertoire level, despite the described differences in CDRH3 lengths.

Overlap analysis reveals considerably greater diversity among human repertoires. The top rows pertain to exact CDRH3 (amino acids) and the bottom rows to clonotypes (same IGHV, IGHJ, and greater than 90% amino acid identity across length-matched CDRH3s). At the level of CDRH3s, the Kymouse repertoires have more unique CDRH3s per sequence sampled (A), are more diverse in their usages (C), despite their limited VD and DJ insertion rates. Diversity is reduced relative to human sequences at longer CDRH3 lengths which in unmutated repertoires require VD/DJ insertions to reach (E). Kymouse repertoires show an opposite pattern in unique sampling rate and diversity when looking at clonotypes (B and D, respectively) but still show reduced diversity versus humans at longer lengths. Overlap among CDRH3s (G) and clonotypes (H) between individuals is considerably higher in Kymice than humans, and more comparable to mice (G).