Adhesion rates of purified human intestinal mast cells to ECM proteins.

(A) Mast cells precultured with SCF (purity, 98% or greater) were incubated for 90 minutes in wells coated with different ECM proteins indicated on the x-axis. Adhesion rates of mast cells, in the presence or absence of 100 ng/mL (54 nM) SCF, were determined by the measurement of histamine content of bound cells (expressed in percentage of total histamine of all cells). The dotted line indicates the background (binding of mast cells to BSA) (n = 5). (B) Dose dependency of the effect of SCF. Mast cells were challenged for 90 minutes with various concentrations of SCF indicated on the x-axis. Results represent the mean ± SD of 3 experiments.