Lysosome in antigen-presenting cell

Lysosomes in antigen-presenting cells, such as dendritic cells, macrophages, and B lymphocytes, are critical intracellular organelles responsible for the degradation of internalized exogenous antigens and their processing into peptides suitable for loading onto major histocompatibility complex (MHC) class II molecules[1][2][3][4][6][7]. Lysosomal hydrolytic enzymes break down engulfed proteins, facilitating their presentation to CD4+ T cells, which is central to adaptive immunity. Lysosomes also participate in the regulation of immune checkpoints and co-stimulatory molecules by controlling their degradation and recycling[4]. Morphological and functional adaptation of lysosomes, including changes in their tubulation, fusion dynamics, or distribution within the cell, is influenced by cellular maturation signals (e.g., lipopolysaccharide, cytokines) and metabolic pathways (e.g., mTOR)[1][6]. While not themselves classical drug targets, modulation of lysosomal function in antigen-presenting cells can alter immune responses and has therapeutic implications in cancer immunotherapy, infectious diseases, and autoimmunity[3][4][5][6].

Other names

Lysosomal compartment in APCsLysosome in dendritic cell/macrophageMHC class II compartment (in some contexts)

Lysosomal pH modulation (e.g., by chloroquine); Inhibition of lysosomal proteases or acidification; Modulation of antigen processing/presentation pathways