The polyclonal antibody reacts with native mouse and human fibrinogen, a plasma protein that is also found in the alpha-granules of platelets. The major receptor for fibrinogen is the activated integrin alphaIIb beta3 (CD41/61). Binding of fibrinogen to mouse alphaIIb beta3 can be inhibited with the monoclonal antibody Leo.H4 (emfret Analytics, #M021-0).