The thymus has two functionally distinct populations of immature alpha beta + T cells: one population is deleted by ligation of alpha beta TCR.
Finkel TH, Cambier JC, Kubo RT, Born WK, Marrack P, Kappler JW. The thymus has two functionally distinct populations of immature alpha beta + T cells: one population is deleted by ligation of alpha beta TCR. Cell. 1989 Sep 22; 58(6):1047-54.