Immune repertoires are the full breadth of B-cell and T-cell receptors being expressed by a human that are available for potential antigen binding. Rees (1) provides estimates suggesting that humans have naive repertoires of about sequences.
Related:
1.
Rees AR. Understanding the human antibody repertoire. mAbs. 2020;12(1). Available from: https://doi.org/10.1080/19420862.2020.1729683