Kinetics of Receptor-Ligand Interactions in Immune Responses
Mian Long1, 2, Shouqin Lü1 and Ganyun Sun1
1National Microgravity Laboratory and Center for Biomechanics and Bioengineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China;
2Corresponding to: Dr. Mian Long, National Microgravity Laboratory and Center for Biomechanics and Bioengineering, Institute of Mechanics, Chinese Academy of Sciences, Beijing 100080, China. Tel: +86-10-6261-3540, Fax: +86-10-6261-3540, E-mail: [email protected]
Received Apr 5, 2006. Accepted Apr 16, 2006.
Receptor-ligand interactions in blood flow are crucial to initiate the biological processes as inflammatory cascade, platelet thrombosis, as well as tumor metastasis. To mediate cell adhesions, the interacting receptors and ligands must be anchored onto two apposing surfaces of two cells or a cell and a substratum, i.e., the two-dimensional (2D) binding, which is different from the binding of a soluble ligand in fluid phase to a receptor, i.e., three-dimensional (3D) binding. While numerous works have been focused on 3D kinetics of receptor-ligand interactions in immune systems, 2D kinetics and its regulations have less been understood, since no theoretical framework and experimental assays have been established until 1993. Not only does the molecular structure dominate 2D binding kinetics, but the shear force in blood flow also regulates cell adhesions mediated by interacting receptors and ligands. Here we provided the overview of current progresses in 2D bindings and regulations. Relevant issues of theoretical frameworks, experimental measurements, kinetic rates and binding affinities, and force regulations, were discussed.
Key Words: kinetics, force, receptor-ligand bond, cell adhesion
Source: Cellular & Molecular Immunology. 2006;3(2):79-86.