Figure 2

Activated MC respond to C5a in vitro. Precursor cell-derived murine MC cultured with IL-3 and SCF were treated or not (Ø) with Ag (DNP-albumin, following a 24 h preincubation period with IgE anti-DNP) for 4 h (A) or ionomycin for 24 h (B). In (C), MC were preincubated with IgE followed or not by Ag treatment for another 24 h. Subsequently, calcium fluxes in response to C5a (1 μg/ml) and ionomycin (750 ng/ml) (A) or in vitro chemotaxis towards C5a (different concentrations in B; 100 ng/ml in C) was measured. One representative experiment of 3 is shown in (A), mean values (± SEM) of 3 independent experiments each in (B, C).