Dissecting Individual Ligand-Receptor Bonds with a Laminar Flow Chamber

TL;DR

This paper reviews how laminar flow chambers and other techniques have advanced understanding of single biomolecular bonds, revealing their mechanical properties, binding states, and environmental effects, while discussing limitations and future frameworks.

Contribution

It provides a comprehensive overview of recent experimental advances in analyzing individual ligand-receptor bonds using laminar flow chambers and compares these with other methods.

Findings

Flow chambers reveal bond response to forces and multiple binding states.

Kinetics of bond formation are influenced by molecular environment.

Limitations of flow chamber techniques are discussed.

Abstract

The most important function of proteins may well be to bind to other biomolecules. It has long been felt that kinetic rates of bond formation and dissociation between soluble receptors and ligands might account for most features of the binding process. Only theoretical considerations allowed to predict the behaviour of surface-attached receptors from the properties of soluble forms. During the last decade, experimental progress essentially based on flow chambers, atomic force microscopes or biomembrane force probes allowed direct analysis of biomolecule interaction at the single bond level and gave new insight into previously ignored features such as bond mechanical properties or energy landscapes. The aim of this review is (i) to describe the main advances brought by laminar flow chambers, including information on bond response to forces, multiplicity of binding states, kinetics of bond formation between attached structures, effect of molecular environment on receptor efficiency and behaviour of multivalent attachment, (ii) to compare results obtain by this and other techniques on a few well defined molecular systems, and (iii) to discuss the limitations of the flow chamber method. It is concluded that a new framework may be needed to account for the effective behaviour of biomolecule association.