A unique T-cell line derived from an HTLV-1-negative adult T-cell leukemia patient.

A unique T-cell line, designated ATL-5T, was established from lymphoma cells in pericardial effusion of an adult T-cell leukemia (ATL) patient not carrying HTLV-1 provirus. The cell line is OKT4 and/or Leu3a+ and OKT8 and/or Leu2a+, but interleukin 2 receptor (IL2R)- and HTLV-1 provirus genome negative, and has cytogenetically abnormal karyotypes. The cell line contains rearranged T-cell receptor beta-chain gene, which was identical in rearrangement pattern to the T-cell receptor beta-chain gene in primary cells. These results suggest that factors other than HTLV-1 may sometimes be associated with HTLV-1-negative ATL. The ATL-5T cell line we describe here is unique, and should contribute to further elucidation of the mechanisms involved in the pathogenesis of HTLV-1-negative ATL and HTLV-1-positive ATL.