A B cell growth factor-dependent cell line derived from a human lymphocytic nodular lymphoma

A B cell line derived from a human nodular lymphocytic lymphoma (Brill-Symmers) was shown to be dependent on the presence of a low molecular weight B cell growth factor (BCGF) for its growth in vitro. The caryotype was normal and no contamination with Epstein-Barr virus (EBV) could be detected. These cells did not respond to recombinant gamma interferon or to recombinant human interleukin 2 (IL-2), although they displayed a weak density of IL-2 receptor sites. They were both responsive to and dependent on BCGF for their multiplication in vitro. Furthermore, the putative receptor for this growth factor (CD23) was detected on these cells and the BCGF-dependent proliferation could be blocked by a monoclonal anti-CD23 antibody. A tumour-derived cell line like this provides an interesting model for studying the mechanisms regulating B cell growth and the early events leading to the process of B cell immortalization.