抄録
The regeneration of the liver is frequently observed after the resection of liver tumor and partial liver transplantation, and it is assumed that the modification of the hematolymphoid system in the liver will occur during this process and influence not only the progress of the primary disease but also liver regeneration itself. In this study, we investigated by flow cytometric analysis the modification of the cell subpopulation in the peripheral blood lymphocytes (PBL), intrahepatic lymphocytes fraction 1, which come into marginal contact with the liver (IHL Fr. 1), and intrahepatic lymphocytes fraction 2, which come into close contact with the liver (IHL Fr. 2). (1) The positive cells of each antigen (Thy1.2, αβTCR, γδTCR, CD4 and CD8) exist in the normal liver as PBL. (2) CD8/CD4 ratio is 0.3-0.4 in PBL and IHL Fr. 1 and significantly higher in IHL Fr. 2 (0.7). (3) Compared with other fractions, the ratio of a/3TCR dull positive cells to whole atiTCR positive cells is low, while (4) the percentage of γδTCR positive cells is high in IHL Fr. 2. These facts suggest that lymphocyte populations in the liver differ from those of PBL. Furthermore, one day after partial hepatectomy, (5) the percentage of the αβTCR dull positive cells decreases in PBL, but remarkably increases to 2.6 times the normal level in IHL Fr. 2 and (6) the ratio of CD8/CD4 increases to 1.4 times in IHL Fr. 2. (7) The percentage of γδTCR positive cells decreases in PBL, but does not significantly change in IHL Fr. 2 during the liver regeneration. These findings reveal that lymphocyte populations different from PBL exist in the liver and respond to stimulus to the liver in different ways from PBL. The mechanism for the modification occurring in the IHL population during liver regeneration and its biological significance are discussed.
