Biological activities of lipid A complexed with bovine-serum albumin.

Abstract

Lipid A preparations from the lipopolysaccharides of four Salmonella minnesota R mutants and one Escherichia coli 0100 R mutant were assayed as soluble complexes with bovine serum albumin for lethality in mice, pyrogenicity in rabbits and complement inactivation. Although generally less active than endotoxic lipopolysaccharides, these lipid · albumin complexes nevertheless exhibited strong biological activity. These results indicate that lipid A contains the endotoxic principle of bacterial lipopolysaccharides.