Cell-surface heparan sulfate and integrins

Cell-surface heparan sulfate (HS) and integrins are two distinct but often functionally linked components of the cell membrane that play critical roles in mediating interactions between the cell and its environment. Heparan sulfate is a complex polysaccharide that acts as a scaffold for growth factors and cytokines, and frequently serves as the initial attachment point for various pathogens, including viruses like Adeno-associated virus (AAV) and SARS-CoV-2 (Bishop et al., 2007, Nature). Integrins are transmembrane heterodimeric proteins that facilitate cell-extracellular matrix adhesion and signal transduction, often acting as co-receptors that trigger endocytosis following initial attachment to HS (Hynes, 2002, Cell). This dual-receptor system is particularly well-documented in viral entry mechanisms, where HS facilitates docking and integrins facilitate internalization (Summerford & Samulski, 1998, Journal of Virology). In disease states, these molecules are frequently exploited by cancer cells for metastasis and angiogenesis, making them significant therapeutic targets. Therapeutic strategies include the use of HS mimetics to block viral or growth factor binding and monoclonal antibodies or small molecules to inhibit specific integrin subunits, though such interventions must balance efficacy with the risk of disrupting essential physiological adhesion and hemostasis.

Other names

Heparan sulfate proteoglycansHSPGsIntegrin receptorsCell surface attachment factors

Drugs targeting these molecules typically act by competitively inhibiting the binding of ligands, such as growth factors or viral proteins, to the cell surface. Integrin-targeted drugs often block the RGD-binding site to prevent cell adhesion or signaling, while heparan sulfate mimetics compete for binding with heparin-binding proteins to inhibit viral attachment and angiogenesis (Hynes, 2002; Bishop et al., 2007).