Comparison of HA-1A and E5 monoclonal antibodies to endotoxin in rats with endotoxaemia.

OBJECTIVE

To investigate the ability of two anti-endotoxin IgM antibodies (10 mg/kg) to prevent the hyperdynamic response induced by infusion of Escherichia coli rough mutant endotoxin core types R1 and R2 in rats.

DESIGN

Randomised blind laboratory study.

SETTING

University department of surgery.

MATERIAL

8 groups of 5 male Sprague-Dawley rats and 10 control animals.

MAIN OUTCOME MEASURE

Percentage change in cardiac output during the period of observation.

RESULTS

E5 provided significant protection against R1 (p = 0.04) but not against R2. HA-1A gave significant protection against R2 (p < 0.04) but not against R1. In clinical isolates of E. coli the R1 type predominates (about 70%).

CONCLUSION

These results may reflect true differences in specificity between the antibodies, but there remains the possibility that these are non-specific effects. Further controls with irrelevant murine and humanized IgM monoclonal antibodies are in progress.