A new human B-cell line, WSU-FSCCL, was established from the peripheral blood of a patient with low-grade follicular small cleaved cell lymphoma in leukemic phase. Both the fresh lymphoma cells and the established cell line exhibit t(14;18)(q32;q21) and t(8;11)(q24;q21) chromosomal translocations, 6q-, 1p+, and +i(1q). PCR analysis confirmed the juxtaposition of the major breakpoint-cluster region of bcl-2 with immunoglobulin heavy chain (JH) gene rearrangements. Southern analysis demonstrated that the 8q24 breakpoint was 5' of c-myc exon 1. The new line grows as a single-cell suspension with a doubling time of approximately 26 hours. It expresses cytoplasmic and cell surface IgM-kappa and reacts with monoclonal antibodies to B-cell antigens. Cells are negative for T-cell and myeloid/monocyte antigens as well as for Epstein-Barr virus nuclear antigen (EBNA). DNA histogram generated by flow cytometry indicated a near diploid stemline. While t(14;18) is common in follicular lymphomas, the t(8;11) is unusual in lymphomas, although it does involve a region frequently aberrant on chromosome 8. The rearrangement of c-myc may have conferred an aggressive clinical behavior seen in the terminal phase of the disease. The role of 11q21 remains undetermined.