Immune cells – non-specific cellular uptake

Non-specific cellular uptake by immune cells refers to the physiological process where cells of the immune system, primarily macrophages and monocytes within the Mononuclear Phagocyte System (MPS), internalize substances like nanoparticles and biologics without specific receptor-ligand binding (Gustafson et al., 2015, Nano Today). This mechanism involves pathways such as phagocytosis and pinocytosis, which are essential for clearing pathogens and cellular debris from the bloodstream (Uribe-Querol & Rosales, 2020, Frontiers in Immunology). In the context of drug development, this process is a major challenge as it often leads to the rapid clearance of therapeutic agents, reducing their half-life and efficacy (Blanco et al., 2015, Nature Nanotechnology). Furthermore, the accumulation of drugs in immune-rich organs like the liver and spleen can cause off-target toxicity. Researchers often employ surface modifications, such as PEGylation, to shield drugs from this non-specific recognition and prolong circulation time (Suk et al., 2016, Advanced Drug Delivery Reviews).

Other names

Mononuclear Phagocyte System uptakeReticuloendothelial System clearanceNon-specific phagocytosisMacrophage-mediated clearanceEndocytic uptake

Non-specific internalization via phagocytosis, pinocytosis, or macropinocytosis by immune cells, leading to systemic clearance or intracellular drug release.