[Effect of the spleen cells from partially splenectomized and partially hepatectomized mice on the proliferation of hepatocytes in the regenerating liver of syngeneic recipients].

Cells of mouse spleen obtained 48 h after foster splenectomy, foster hepatectomy, resection of 2/3 of spleen or 36 h after resection of 2/3 of liver were introduced intravenously into partially hepatectomized (resection of 2/3 or 1/4 of liver) syngeneic recipients. Cells of regenerating spleen sharply inhibited the mitotic activity of cells of the recipient liver following resection of 1/4 of liver 48 h after the operation and introduction of cells. Inhibition proved to be dose-dependent: it became apparent when 30 million cells were introduced, increased at a dose of 60 million cells and remained at the same level at higher doses. Division of hepatocytes after resection of 1/4 of liver was inhibited by spleen cells taken in the donors 36 h after partial hepatectomy. Spleen cells of intact and pseudo-operated donors had no such ability. Introduction of 60 million of cells of the regenerating spleen and of the spleen of partially hepatectomized animals into recipients with resection of 2/3 of liver did not inhibit reliably the division of hepatocytes, thus indicating the dependence of inhibition on the level of suppressors in the organism. Resection of a major part of liver was accompanied by a greater decrease in the activity of endogenous suppressors which could not be recovered by the introduced cells. Inhibition of cell division by suppressors was not organ specific. Suppressors inhibited proliferation in liver irrespective of the site of operation.