The activation state of human intrahepatic lymphocytes

Abstract

The immune tolerance induced by the liver as an allograft is difficult to reconcile with the evidence that the liver selectively accumulates activated T cells from the circulation. However, much of this information is based on murine liver lymphocytes that were isolated using enzymatic digestion. In the present study we made use of a novel resource, the lymphocytes isolated during the perfusion of living donor liver lobe prior to transplantation. These healthy human liver lymphocytes displayed surface markers indicating a high degree of activation of natural killer cells, CD56(+) T cells, CD4(+) T cells and CD8(+) T cells. These properties were independent of enzymatic treatment or the details of cell isolation. We conclude that the healthy human liver is a site of intense immunological activity.