Soluble complement receptor type 1 protects rats from lethal shock induced by anti-Crry antibody following lipopolysaccharide priming.
BACKGROUND: In rats primed with a trace amount of lipopolysaccharide (LPS), acute lethal shock is induced following the injection of monoclonal antibody against a membrane inhibitor of complement (anti-Crry). Administration of cobra venom factor to exhaust complement before the LPS priming can prevent the lethal reaction. Therefore, we evaluated whether soluble complement receptor type 1 (sCR1), which inhibits complement reaction, can interfere with lethal shock when administered after LPS priming or even after anti-Crry injection. METHODS: sCR1 was administered intravenously before or after the administration of anti-Crry, and the effects on blood pressure and acute lethality were determined. RESULTS: Administration of sCR1 could rescue rats from lethal shock even when it was administered after anti-Crry injection, which immediately causes a blood pressure decrease leading to lethal shock. CONCLUSION: sCR1 may be an effective treatment for acute shock involving complement activation.