Article Figures & Data
Figures
- FIG 1
Trogocytosis is a broad, developing concept. In the central nervous system, microglia use trogocytosis to remodel neuronal synapses, and the parasite N. fowleri kills human cells through trogocytosis. Immune cells take bites out of other human cells. Bacteria such as F. tularensis exploit trogocytosis/merocytophagy to spread between cells. Macrophages can perform trogocytosis to kill antibody-opsonized cells. E. histolytica kills human cells by performing trogocytosis. Neutrophils kill T. vaginalis through trogocytosis. Primordial germ cells in C. elegans are nibbled by endodermal cells. D. caveatum kills other Dictyostelium species through trogocytosis. (Courtesy of Anita Impagliazzo, reproduced with permission.)
- FIG 2
Examples of trogocytosis within and between species. (a) E. histolytica kills human cells through trogocytosis. E. histolytica is stained with cell tracker green, and human Jurkat T cell membranes are stained with DiD (pink). Arrows, ingested bites. (b) Neutrophils kill T. vaginalis through trogocytosis. T. vaginalis membranes are stained with streptavidin-488 (green), and neutrophils are stained with cell tracker deep red (pink). Arrows, ingested bites. (c) Macrophages can perform trogocytosis to kill antibody-opsonized cells. Macrophages are stained with anti-CD45 (green), Raji B cells are opsonized with trastuzumab (red), and nuclei are stained with Hoechst stain (blue). Arrows, ingested bites. (d) E. histolytica acquires and displays human cell membrane proteins through trogocytosis. E. histolytica is stained with cell tracker green, human anti-MHC-I is shown in red, and nuclei are stained with 4′,6′-diamidino-2-phenylindole (DAPI) (blue). Arrows, acquired MHC-I. (Reprinted from references 20, 41, and 96 with permission.)
- FIG 3
The molecular mechanism underlying trogocytosis. (a) T cell trogocytosis. T cell receptors engage with antigen bound by MHC. The small GTPases TC21 and RhoG play roles in trogocytosis, along with PI3K and actin. Membrane proteins from the antigen-presenting cell are ultimately displayed on the T cell. The cells separate and remain viable. (b) C. elegans endodermal cell trogocytosis. The small GTPase CED-10/Rac1 plays a role in trogocytosis, along with actin, Lst-4/SNX9, and dynamin-1. Lst-4/SNX9 has a role in membrane bending, and dynamin-1 has a role in membrane scission. Some P-granules and mitochondria are removed from the primordial germ cell. The cells separate without cell death, and after trogocytosis, the primordial germ cell is smaller and contains fewer P-granules and mitochondria. (c) E. histolytica trogocytosis. Glycoproteins on the human cell surface are engaged by the Gal/GalNAc lectin. The kinase EhC2PK plays a role in trogocytosis, together with PI3K and actin. Membrane proteins from the human cell are ultimately displayed on the amoeba. The cells separate once the human cell is killed. (Courtesy of Anita Impagliazzo, reproduced with permission.)
