Antigen CD61, also known as β3 subunit, is an integrin family protein that pairs with αIIb or αV subunits, which is important for both outside-in and inside-out signalingcontributing to cell adhesion. αIIbβ3 integrin (i.e. glycoprotein (GP) IIbIIIa) is the central receptor of platelet aggregation. αVβ3 integrin plays a critical role in angiogenesis.  Our anti-CD61 monoclonal antibodies are generated inhybridoma cells isolated from β3 knockout mice immunized with purified recombinant human β3 integrin.