REDISTRIBUTION OF LYMPHOCYTES FOLLOWING ESCHERICHIA-COLI SEPSIS

Infusion of endotoxin elicits lymphopenia and a transient granulocytop enia followed by granulocytosis in peripheral blood. The purpose of th is study was to investigate which tissues the lymphocytes are redistri buted to in response to endotoxaemia. Lymphocytes were isolated from t he peripheral blood of 20 rabbits, labelled with Indium-111-tropolene and reinjected intravenously into the rabbits. Ten rabbits received an infusion of Escherichia coli endotoxin 2 mug/kg-1, while 10 rabbits r eceived isotonic saline and served as a control group. The redistribut ion of lymphocytes was imaged with a gamma camera, and calculated with an interfaced computer before, and 2, 4 and 6 h after infusion of end otoxin or saline. Interleukin-1beta and serum cortisol were measured. Following endotoxaemia the lymphocytes in peripheral blood decreased f rom 1.95 10(9)/1 to 0.83 6 h later. Interleukin-1beta and serum cortis ol increased significantly. The radioactivity of labelled cells in the spleen and in the heart and lungs decreased to 83.3% and 87.8% of ini tial values respectively, 6 h after infusion of endotoxin. The radioac tivity of the lymphatic tissue in and around the intestine increased t o 128.8% of initial values. The results indicate that endotoxaemia ind uces redistribution of lymphocytes from peripheral blood and spleen to lymphatic tissue.