Effect of LAK cells on liver regeneration after partial hepatectomy

Lymphokine activated killer (LAK) cells can destroy not only tumor cells but also syngeneic regenerating liver cells. This study was started to determine the effect of passive transfer of LAK cells on liver regeneration after partial hepatectomy. C3H mice were received 70% hepatectomy and LAK cells were injected intravenously at a dose of 5 X 10(7) cells/body. After 36 hours, 3H-thymidine uptake into the residual liver was measured. LAK cells transferred group showed 31% suppression compared with control group. In vitro, 24 hours addition of LAK cells to the primary culture of regenerating liver cells caused 97% suppression of 3H-thymidine uptake at effector to target ratio, 50/1. Then we examined the effects of IL-2 administration on liver regeneration. Though IL-2 showed no effect on cultured liver cells, intraperitoneal administration of IL-2 after hepatectomy at a dose of 1 X 10(4)u/body 5 times every 8 hours brought 38% suppression of 3H-thymidine uptake of the residual liver. Cyclosporine A, which can suppress the IL-2 production of lymphocytes, promoted liver regeneration 45% over the control at a dose of 10 mg/kg. These results suggest that LAK cells could regulate liver regeneration.