Modeling multivalent ligand-receptor interactions with steric constraints on configurations of cell-surface receptor aggregates.

ABSTRACT: We use flow cytometry to characterize equilibrium binding of a fluorophore-labeled trivalent model antigen to bivalent IgE-FcepsilonRI complexes on RBL cells. We find that flow cytometric measurements are consistent with an equilibrium model for ligand-receptor binding in which binding sites are assumed to be equivalent and ligand-induced receptor aggregates are assumed to be acyclic. However, this model predicts extensive receptor aggregation at antigen concentrations that yield strong cellular secretory responses, which is inconsistent with the expectation that large receptor aggregates should inhibit such responses. To investigate possible explanations for this discrepancy, we evaluate four rule-based models for interaction of a trivalent ligand with a bivalent cell-surface receptor tha

SUBMITTER: Monine MI 

PROVIDER: S-EPMC2800967 | biostudies-literature | 2010 Jan

REPOSITORIES: biostudies-literature