The lymphoid liver: Considerations on pathways to autoimmune injury Hiroto Kita, Judy Van De Water, M.Eric Gershwin  Gastroenterology  Volume 120, Issue 6, Pages 1485-1501 (May 2001) DOI: 10.1053/gast.2001.22441 Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 1 Immunologic components of the liver. The liver should be considered a lymphoid organ based not only on the properties of hepatocytes, but also on constituent cell populations. There are 2 separate regions of the liver depicted, the (A) sinusoid and the (B) portal tract, illustrating the interrelationship between the hepatic and the immune constituents. Gastroenterology 2001 120, 1485-1501DOI: (10.1053/gast.2001.22441) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 2 Potential mechanisms of immune-mediated damage in AIH. To date, there is no known immunologic basis for cellular injury in AIH, although autoantibodies have been implicated through an ADCC- or C'-mediated pathway. The involvement of T cells is still highly speculative. Gastroenterology 2001 120, 1485-1501DOI: (10.1053/gast.2001.22441) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 3 Potential mechanisms of bile duct damage in PBC. The exact pathway of immune-mediated tissue destruction in PBC is unknown, however, it has been suggested that PDC-E2–specific IgA may be involved during the normal course of transcytosis. Additional possibilities include NKT-mediated ADCC and/or CD8+ CTL-mediated damage. Gastroenterology 2001 120, 1485-1501DOI: (10.1053/gast.2001.22441) Copyright © 2001 American Gastroenterological Association Terms and Conditions

Fig. 4 Little is known about the role of the immune system in the periductular fibrosis and eventual destruction of bile ducts in PSC. CD8+ T cells have been shown to be present in the portal tract of PSC liver, however, no antigen specificity has been shown for these cells. There is the suggestion of a link between PSC and inflammatory bowel disease with respect to the influence of cytokines on the bile ducts. There is no known role for the humoral immune system in the pathology of PSC. Gastroenterology 2001 120, 1485-1501DOI: (10.1053/gast.2001.22441) Copyright © 2001 American Gastroenterological Association Terms and Conditions