CDS-POSITIVE ADULT T-CELL LEUKEMIA-CELLS WITH AN INTEGRATED DEFECTIVEHTLV-I GENOME SHOW A PARACRINE GROWTH TO IL-2

We describe a 50-year-old man with adult T-cell leukemia complicated b y laryngeal tuberculosis whose tumor cells proliferate in response to IL-2 in a paracrine manner. On admission, the patient's white blood ce ll count was 17,900/mm(3); 73% were abnormal lymphocytes with convolut ed nuclei. FACS analysis showed that the tumor cells were CD4-negative , CD8-positive T cells. Southern blot analysis of tumor cells revealed integration of a defective HTLV-1 genome lacking gag and pol genes. H e was diagnosed with chronic ATL complicated by laryngeal tuberculosis . The primary leukemic cells expressed IL-2R alpha and IL-2R beta dete cted by FACS and Northern blot analysis and showed marked growth in re sponse to exogenously added recombinant IL-2 in short-term cultures. N orthern blot analysis did not show any IL-2 mRNA. We have previously d emonstrated that primary leukemic cells from some ATL patients grow in response to IL-2 in an autocrine or paracrine manner. These results s uggest that in CD8 ATL, IL-2 may be involved in a paracrine manner. (C ) 1994 Wiley-Liss, Inc.