FARAGE, A NOVEL EARLY B-CELL LYMPHOMA CELL-LINE WITH TRISOMY 11

Farage, a new cell line established from a lymph node biopsy of a patient with non-Hodgkin's lymphoma (NHL), constitutes a clonal expansion of cells at a distinct stage of B-cell differentiation. The cells lack both T and myeloid surface markers, express B cell surface antigens including CD19, CD20, CD22, HLA-DR, were positive for C3 receptors and EBNA and expressed BCL-2. No immunoglobulin determinants could be demonstrated on the cell surface. Intracellular IgM and kappa chains were detected, in an unusual but distinct localization and appeared to be localized to the nucleus or to the perinuclear area without any spread to the cytoplasm, as seen in the early B cells. Southern blot DNA analysis showed rearrangement of one of the IgJH alleles. The Farage cells were negative for B cell activation antigens including CD25, CD11b, HC2 and Bly-7. The cells were negative for two anti CD-10 (CALLA) reagents but weakly positive with one. Interestingly they were strongly positive for both nuclear and cytoplasmic TdT. In addition the TCRγ gene but not the TCRβ was rearranged in one allele and the TCRα was not detected. Cytogenetic studies showed the cells to be trisomic for chromosome 11. In this case, it is proposed that the perinuclear localization of the immunoglobulin may be characteristic for early B cell stages of differentiation. © 1992 Informa UK Ltd All rights reserved: reproduction in whole or part not permitted.