Figure 4.
Co-cross-linking of CD32 and CD40 is not involved in the inhibitory effect on immunoglobulin E (IgE) synthesis. Tonsillar B cells were induced with interleukin-4 (IL-4) and soluble CD40 ligand (sCD8/CD40L) (upper panel) or with anti-CD40 F(ab′)2 fragments (lower panel) in the absence or presence of increasing concentrations (µg/ml) of intact CD32 antibody. IgE levels were quantified after 9 days by enzyme-linked immunosorbent assay (ELISA). The data were analysed for statistical significance by using the Student's t-test (*P < 0·05, **P < 0·01).