Induction of Fc(ε)-receptor bearing cells in vitro in human peripheral lymphocytes

Fc(ε)R-bearing lymphocytes were induced in vitro by the culture of peripheral lymphocytes from ragweed -sensitive patients with antigen E together with, or followed by, human IgE. Neither antigen E alone nor IgE alone induced Fc(ε)R(+) cells. As expected, culture of normal lymphocytes with the antigen and IgE failed to increase Fc(ε)R(+) cells. However, mixed lymphocyte cultures from two normal individuals responded to human IgE for the induction of Fc(ε)R(+) cells. In both antigen-stimulated and mixed lymphocyte cultures, a portion of Fc(ε)R(+) cells induced in vitro were T lymphocytes. Evidence was obtained that Fc(ε)R(+) cells are involved in the induction of Fc(ε)R(+) cells. Depletion of Fc(ε)R(+) cells in the lymphocytes from ragweed-sensitive patients, before culture with antigen E and IgE, abolished tha ability of the lymphocytes to respond to IgE for an increase in Fc(ε)R(+) cells.