Mice with a null mutation in the terminal deoxynucleotidyl transferase (TdT) gene harbor immunoglobulin and T cell receptor repertoires essentially devoid of N‐region diversity. Consequently, the CDR3 loops important for antigen recognition are shorter and considerably less diverse than those of wild‐type controls. We find surprisingly normal immune responses in TdT° mice, as regards both efficiency and specificity. This provokes a reconsideration of the assumption that N‐region diversity is required for an effective T and B cell repertoire.
- Knockout mice
- N‐region diversity
- T cell receptor
- T cell repertoire
- Terminal deoxynucleotidyl transferase