Subendothelial extracellular matrix proteins (SECM) (SECM)

The subendothelial extracellular matrix (SECM) is a complex assembly of proteins, primarily collagen (Types I, III, and IV), von Willebrand factor (vWF), fibronectin, and laminin, situated beneath the vascular endothelial layer (Ruggeri & Mendolicchio, 2007). Under physiological conditions, the SECM is sequestered from blood components, but vascular injury or plaque rupture exposes these proteins, initiating platelet adhesion and thrombus formation (Farndale et al., 2004). This interaction is mediated by platelet receptors such as Glycoprotein VI (GPVI) and integrin alpha-2-beta-1 binding to collagen, and Glycoprotein Ib-IX-V binding to vWF (Stegner et al., 2020). While vital for hemostasis, excessive SECM-induced thrombosis is a hallmark of cardiovascular diseases, including myocardial infarction and stroke (Savage et al., 1998). Therapeutic strategies involve direct inhibitors like Caplacizumab, which targets vWF, or Revacept, a soluble GPVI-Fc fusion protein that binds exposed collagen (Ungerer et al., 2011). Additionally, the SECM serves as a target for site-specific drug delivery, utilizing collagen-binding domains to localize anti-inflammatory or thrombolytic agents to injured vessels (Katsube et al., 2021). By focusing on the injury site, these approaches aim to increase local efficacy while minimizing systemic side effects, such as bleeding.

Other names

Subendothelial matrixVascular extracellular matrixSubendothelial basement membraneSECM

Inhibition of platelet-matrix interaction by blocking binding sites on collagen or von Willebrand factor, or by using matrix-binding domains for targeted drug delivery.