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Updated: Jul 5, 2026

Generation of Human CD40-activated B cells
Published on: October 16, 2009
Long-term human B cell lines dependent on interleukin-4 and antibody to CD40
J Banchereau1, P de Paoli, A Vallé
1Laboratory for Immunological Research, Dardilly, France.
Abstract:
CD40 is a 45- to 50-kilodalton transmembrane glycoprotein expressed on B lymphocytes, epithelial cells, and some carcinoma cell lines. Human resting B lymphocytes entered a state of sustained proliferation when incubated with both the mouse fibroblastic Ltk- cell line that had been transfected with the human Fc receptor (Fc gamma RII/CDw32) and monoclonal antibodies to CD40. In combination with interleukin-4, factor-dependent long-term normal human B cell lines were generated that were consistently negative for Epstein-Barr viral infection. Thus, cross-linking of CD40 is likely to represent an important phenomenon in the clonal expansion of B cells.
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