PF4 and type 2 diabetes mellitus: However, when the clamp was continued to hypoglycemia, four proteins changed in controls from baseline [Thrombospondin-1 (p < 0.014), platelet factor 4 (p < 0.01), Platelet basic protein (p < 0.008), and Vitamin K-dependent protein C (p < 0.00003)], but only one in T2D [Vitamin K-dependent protein C (p < 0.0002)].