In vivo studies of endotoxin removal by lysine–cellulose adsorbents

A new type adsorbent for removal of bacterial endotoxins was prepared by immobilizing lysine covalently onto cellulose beads. Endotoxins (Escherichia coli O55: B5) were injected into 13 healthy New Zealand white rabbits to induce infectious symptoms. Hemoperfusion using the adsorbent column removed endotoxins in the blood of eight rabbits during 2 h while other five rabbits were used as control. The mean blood endotoxin concentration was reduced significantly from 5.56±0.54 EU/ml (1 EU=100 pg) before treatment to 0.41±0.26 EU/ml after perfusion as measured by the limulus amebocyte lysate test (Chromogenix). Liver function and renal function tests showed significant improvement of septic symptoms in contrast to the control group. Other parameters such as superoxide dismutase and malondialdehyde were ameliorated markedly after the treatment. Moreover, the adsorbent showed good results in mechanical strength, blood compatibility and cytotoxicity, which suggested that lysine–cellulose adsorbent was of high ET-binding efficacy without significant side effect. It has a high potential of clinical application for treatment of patients with severe sepsis.