The present disclosure relates to anti-TRBCl antigen binding domains characterized by the sequences of the variable chains. The CDRs sequences of the variable chains are : (VH CDR1) GYTFT, (VH CDR2) NPYNDDIQS, (VH CDR3) GAGYNFDGAYRFFDF; and (VL CDR1) RSSQRLVHSNGNTYL, (VL CDR2) RVSNRFP, (VL CDR3) SQSTHVPYT. The claimed humanized antibodies derive from the murine JOVI antibody. Uses in cancer therapy.