T lymphocytes can be divided into 2 populations: αβ T and γδ T cells. They are distinguished by the structure of their cell receptors. The αβ T cell receptors (TCR) are composed of α and β chains and the γδ TCRs are composed of γ and δ chains. αβ T cells account for a majority of T lymphocytes in peripheral blood, while γδ T cells only account for 1-5%.