Fig. 2.

Listeria- and α2β1 integrin-dependent IL-6 secretion in the absence of degranulation. WT and α2-null (KO) FSMCs (5 × 10⁴ cells/well) were stimulated with Listeria plus anti-Listeria antibody and serum (LAS) for 1 h or anti-DNP IgE overnight followed by 1 h of stimulation with DNP-HSA (IgE + DNP). Cell-free supernatants were analyzed for the release of IL-6 (white bars) or β-hexosaminidase (black bars) via ELISA or as described in Materials and Methods, respectively. The secretion of IL-6 by α2-null (KO) FSMCs was significantly less than that by WT FSMCs (** p< 0.009). p values were determined using unpaired Student's t test. Data are expressed as means ± SEM and are representative examples of at least 3 similar experiments.