Antigen-presenting cell phagosomal membrane

The antigen-presenting cell (APC) phagosomal membrane is a specialized lipid bilayer that forms during phagocytosis to sequester internalized pathogens or debris within a vesicle known as a phagosome [1]. In professional APCs like macrophages and dendritic cells, this membrane is essential for the immune response, as it serves as the site for pathogen degradation and the processing of antigens for presentation on MHC class I and II molecules [2]. The membrane is highly dynamic, undergoing a maturation process that involves sequential fusion with endosomes and lysosomes, which alters its protein and lipid composition to facilitate acidification and enzymatic activity [3]. While the membrane itself is a cellular compartment rather than a single protein, it contains numerous critical therapeutic targets, including Toll-like receptors (TLRs 3, 7, 8, and 9) and the NADPH oxidase complex (NOX2) [4]. Drugs such as chloroquine and hydroxychloroquine modulate the phagosomal environment by increasing pH, thereby interfering with antigen processing and TLR signaling, which is useful in treating autoimmune diseases like systemic lupus erythematosus [5]. Additionally, the phagosomal membrane is a focal point for vaccine delivery strategies aimed at enhancing cross-presentation to CD8+ T cells for cancer immunotherapy [6].

Other names

Phagosomal membranePhagolysosomal membraneEndophagosomal membranePhagosome membrane

Inhibition of phagosomal acidification, Toll-like receptor agonism, V-ATPase inhibition, NADPH oxidase modulation