Immunological characteristics of cells entering the liver with portal blood.

The mononuclear cell populations were characterized phenotypically and functionally in the splenic, mesenteric, portal, sinusoidal, and hepatic venous blood. We found higher concentrations of mononuclear cells in splenic than mesenteric and portal blood; splenic blood contained high numbers of cells with Fc, C3b receptors and surface immunoglobulin and OX8+ (cytotoxic/suppressor) cells. Liver sinusoidal blood was enriched, compared with inflowing portal blood, in cells with Fc, C3b receptors and surface immunoglobulin, OX+8 cells, and natural killer and killer cells. These findings indicate that the spleen may be the main source of migrating streams of cells to the liver and that cytotoxic subsets of these cells are retained in that organ.