B cell hybridoma presents both B-cell and T-cell epitopes for stimulating antibody production via CD23 pathway.

CD23+ B cell hybridoma 17A11, pulsed with IgE:TNP-KLH triggered IgA, IgG, and IgE antibody production via CD23-mediated presentation. Prior anti-CD23 treatment abrogated 95% of the humoral antibody responses. Both B and T cell epitopes were presented by 17A11 B cell epitopes as recognized by IgG but not T cell epitopes were sensitive to treatment with 0.2 M acetic acid. Efficacy of antigen presentation via CD23 on 17A11 was comparable to that mediated via surface immunoglobulins (sIg) on a CD23 negative 4.5 parental fusion partner B cell line. This is the first demonstration that IgE:TNP-KLH pulsed B cell hybridomas present both B- and T-cell epitopes in stimulating IgA, IgG, and IgE antibody production, and raise a pertinent issue whether IgE antibodies produced under pathophysiological conditions may serve as positive feedback signal for sustaining production of different classes of antibodies.