Interactions of costimulatory molecules
Affinities and stoichiometries of signalling complexes formed by members of the B7/CD28 family. Bivalency is estimated to increase the stability of a given complex 100-fold. Activating B7-2/CD28 complexes are therefore predicted to be 10,000-1,000,000-fold less stable than inhibitory B7-1/CTLA-4 complexes.