High-throughput analysis of the T cell receptor gene repertoire in low-count monoclonal B cell lymphocytosis reveals a distinct profile from chronic lymphocytic leukemia

Next-generation sequencing (NGS) of the T cell receptor (TR) gene repertoire in chronic lymphocytic leukemia (CLL) offered evidence of antigenic selection leading to the emergence of expanded T cell clones. However, little is known regarding the TR repertoire composition at the early stages of CLL, particularly low-count monoclonal B cell lymphocytosis (LC-MBL). To address this issue, we performed high-throughput TR beta chain (TRB) gene repertoire profiling by next generation sequencing (NGS) in individuals with LC-MBL of different subtypes (namely “CLL-like”, “atypical CLL-like” and “non CLL-like”) and age-matched individuals without MBL, complemented by comparisons against published data from CLL and healthy individuals of different ages.