Endocytosis is the process by which cells absorb foreign substances and molecules, including viruses. Viruses such as SARS-CoV-2 use this process to enter human cells.

Types of endocytosis

  • Clathrin-mediated endocytosis: Vesicles formed this way are about 100 nm in diameter and coated in the protein clathrin. These can be mediated by receptor binding and can also contain Antibodies.
  • Caveolin-mediated endocytosis: Vesicles formed this way are smaller, about 50 nm in diameter. The resulting bilayer is enriched in cholesterol and glycolipids.
  • Phagocytosis: Absorption of larger molecules with vesicles up to 750 nm in diameter.