Monocyte-independent stimulation of human B lymphocytes by phorbol myristate acetate
Bertoglio, J.H.
Journal of Immunology 131(5): 2279-2281
1983
ISSN/ISBN: 0022-1767 PMID: 6605383 Document Number: 218549
Phorbol myristate acetate (PMA) induces a low level of proliferation in purified human B lymphocytes when added in nanomolar concentrations to the culture medium. Much higher levels of thymidine incorporation, however, are obtained in the presence of other B cell stimuli such as anti-IgM antibodies or Staphylococcus aureus Cowan Strain 1 (SAC). The peak activity of PMA was observed on day 3 of B cell cultures containing either anti-IgM or SAC. The rigorous depletion of monocytes as well as add-back experiments indicate that the effect of PMA on anti-IgM-stimulated B cells is not mediated by the stimulation of accessory cells. Thus, PMA acts as a very potent mitogenic agent for human B cells under culture conditions that are commonly used to assess B cell growth factor activity.