['Leucocytes have been implicated as mediators of renal ischaemia-reperfusion injury. This study aimed to demonstrate the effect of white cells in early renal reperfusion injury using an isolated haemoperfused porcine kidney model.', 'After 2 h cold storage, porcine kidneys were perfused with normothermic autologous blood using an isolated organ preservation system. This was designed using cardiopulmonary bypass technology, and perfusion commenced with a circulating serum creatinine level of 1000 micromol/l. In group 1 (n = 6) a leucocyte filter was included in the circuit and in group 2 (n = 6) non-filtered blood was used.', 'The mean(s.d.) area under the curve for serum creatinine was lower in the leucocyte-depleted experiments (1286(214) versus 2627(418); P = 0.002). Leucocyte depletion also led to improved urine output (191(75) versus 70(32) ml/h; P = 0.002) and higher creatinine clearance (10.6(2.8) versus 1.9(1.0) ml/min; P = 0.002). Renal blood flow, oxygen consumption and acid-base homeostasis were all improved by perfusion with leucocyte-depleted blood, and histological tubular damage was ameliorated.'] Does leucocyte depletion improve renal function during reperfusion using an experimental isolated haemoperfused organ preservation system?