Negatively charged phospholipid surfaces (PS-rich surfaces)

Negatively charged phospholipid surfaces, primarily characterized by the presence of externalized phosphatidylserine (PS), serve as critical physiological and pathological signaling platforms. In healthy cells, flippase enzymes maintain these anionic lipids on the inner leaflet of the plasma membrane; however, during apoptosis, cellular stress, or oncogenic transformation, PS is translocated to the outer leaflet (Birge et al., 2016, Cell Death & Differentiation). This externalization creates a procoagulant surface that facilitates the assembly of tenase and prothrombinase complexes, essential for blood clotting (Lentz, 2003, Thrombosis and Haemostasis). In the context of oncology, these surfaces act as a global immunosuppressive signal in the tumor microenvironment, inhibiting the maturation of dendritic cells and promoting an M2-like anti-inflammatory macrophage phenotype (Thorpe, 2010, Journal of Controlled Release). Therapeutic strategies involve using antibodies like bavituximab to mask these surfaces and restore anti-tumor immunity or utilizing PS-binding proteins like Annexin V for the molecular imaging of cell death (Belhocine et al., 2004, Clinical Cancer Research). Furthermore, certain viruses exploit these negatively charged surfaces through 'apoptotic mimicry' to gain entry into host cells.

Other names

Anionic phospholipid surfacesExternalized phosphatidylserineProcoagulant membrane surfacesAcidic phospholipid membranesPhosphatidylserine-rich membranes

Binding to externalized anionic phospholipids to block immunosuppressive signaling, induce antibody-dependent cellular cytotoxicity (ADCC), or provide a scaffold for the assembly of procoagulant complexes.