Liver regeneration and lymphocyte activation.

A 70 per cent partial hepatectomy in the rat results in a massive deoxyribonucleic acid synthesis not only in the remaining liver cells but also in the lymphoid organs. Serum factor present in the rat after hepatectomy stimulated both hepatocytes and lymphocytes in culture. Lethally irradiated rats, followed by a partial hepatectomy, could be restored their regeneration ability only when the lymphocytes taken from rats after hepatectomy were injected. A hypothesis is that the replications of the regenerating liver cells and the antigen stimulated lymphocytes are triggered by a common pathway, probably through adenosine 3':5'-cyclic phosphate activation.