Change in nomenclature for the immunologic synapse from Troxis Necrosis to trogocytosis.

The immunologic synapse mechanism of liver necrosis was termed Troxis Necrosis meaning "nibbling". (Wang MX et al. and French SW. Exp Mol Pathol 2001, 71: 137-146). This mechanism of liver injury was first named "Piecemeal Necrosis" by Hans Popper. It is involved in autoimmune hepatitis, HCV, HBV, primary biliary cirrhosis and steatohepatitis. This process involves the T cell receptor (TCR) which binds to the hepatocyte antigen presenting major histocompatibility complex (MHC) on the hepatocytic plasma membrane which quickly leads to the removal of the complex from the liver and uptake by the CD4 lymphocyte. This process is performed by the immunologic synapse now called trogocytosis meaning "gnaw" (Martinez-Martin N et al., Immunity 2011, 35: 208-222 and Dustin ML, Cancer Immunol Res 2014, 2: 1023-1033). The repeated episodes of uptake of the hepatocyte bite by bite causes the hepatocyte to slowly disappear like the Cheshire cat. This immunological synapse process is also involved in drug hepatitis, Hashimoto's thyroiditis, type I diabetes, autoimmune adrenalitis, autoimmune gastritis and cancer therapy. Treatment of Alzheimer's disease is also now being studied with PD-L1 antibody as used in the treatment of cancer allowing recruitment of disease modifying leukocytes to the sites of brain pathology (Schwartz M. Science 2017, 357: 254-255). Acknowledgement: Supported by a Grant from NIAAAUO1-021898.