The rearrangement of TCR germline V(D)J genes during T cell development, including allelic exclusion and tolerance selection, ensures the clonal selection theory, which states that ‘a lymphocyte expresses only one type of antigen receptor’. This forms the basis for T cell-specific responses. However, the existence of ‘dual TCR T cells’ has consistently been supported by specific experimental evidence. Detailed reports on the origin, proportion, tissue distribution, and CDR3 characteri...
