The present invention provides (1) a blood-treating material comprising a lipopolysaccharide derived from cell walls of Gram-negative bacteria and immobilized by an insoluble carrier containing an amino group or a carboxyl group and (2) a process for producing the blood-treating material characterized by reacting a condensing agent with a mixture of the lipopolysaccharide and the insoluble carrier.
Lipopolysaccharides have been known to have antitumor effects against malignant tumors. However, they could not be used safely, since their fatal doses are very close to the minimum effective doses in the treatment of the tumors.
The present invention makes it possible to reduce the lethal toxicity of the above-mentioned lipopolysaccharides and provide a new blood-treating material that can be used safely for therapy of cancer, because this blood-treating material has antitumor effects similar to those of the lipopolysaccharides derived from cell walls of Gram-negative bacteria but no fatal effects.