The liver is a site where activated CD8(+) T cells are trapped and destroyed at the end of an immune response. The intrahepatic accumulation of activated murine TCR transgenic CD8(+) T cells was significantly reduced when either ICAM-1 or VCAM-1 was blocked by specific Ab. These two adhesion mechanisms account for essentially all the trapping of activated CD8(+) T cells in the mouse liver. Although the ICAM-1-mediated trapping depends on the capacity of the vasculature and/or the parenchymal cells to present Ag, the accumulation of cells through VCAM-1 does not require Ag recognition. Thus, Ags expressed by the non-bone marrow-derived cells in the liver actively cause CD8(+) T cell accumulation through TCR-activated ICAM-1 adhesion, but the liver can also passively sequester activated CD8(+) T cells that do not recognize intrahepatic Ag, through VCAM-1 adhesion.
John, B., Crispe, I.N., 2004. Passive and active mechanisms trap activated CD8+ T cells in the liver. Journal of Immunology 172, 5222-5229.