Established from transplantable tumors induced in syngeneic mice inoculated with cell suspensions prepared from lymph nodes infiltrated by lymphatic leukemia induced in 6-week-old DBA/2 mice by Rauscher virus (present in supernate of JLSV-9 cells); described as expressing T cell surface markers (Thy-1, T-200, Lyt-1), high constitutive TdT activity, and as differentiating along T-helper lineage in response to treatment with DMSO or phorbol ester TPA