Receptor-ligandinteractionsinbloodflowarecrucialtoinitiatesuchbiologicalprocessesasinflammatorycascade,plateletthrombosis,aswellastumormetastasis.Tomediatecelladhesion,theinteractingreceptorsandligandsmustbeanchoredontotwoapposingsurfacesoftwocellsoracellandasubstratum,i.e.,two-dimensional(2D)binding,whichisdifferentfromthebindingofasolubleligandinfluidphasetoareceptor,i.e.,three-dimensional(3D)binding.Whilenumerousworkshavebeenfocusedon3Dkineticsofreceptor-ligandinteractionsintheimmunesystem,2Dkineticsanditsregulationshavebeenlessunderstood,sincenotheoreticalframeworkorexperimentalassayswereestablisheduntil1993.Notonlydoesthemolecularstructuredominate2Dbindingkinetics,buttheshearforceinbloodflowalsoregulatescelladhesionmediatedbyinteractingreceptorsandligands.Here,weprovideanoverviewofcurrentprogressin2Dbindingandregulations,mainlyfromourgroup.Relevantissuesoftheoreticalframeworks,experimentalmeasurements,kineticratesandbindingaffinities,andforceregulationsarediscussed.
