Abstract: Compositions and methods for the treatment and diagnosis of lipopolysaccharide-related conditions and coagulant-related disease are provided. Compositions include polypeptides which are identical or homologous to a certain cationic protein (CAP18) obtained from mammalian granulocytes, particularly including a reactive nitrogen inhibiting peptide (RNIP) fragment found at the carboxy-terminus of CAP18. Polypeptides are capable of binding to LPS and inhibiting LPS-mediated activation of macrophage, as well as interfering with the clotting cascade to inhibit coagulation in conditions such as disseminated intravascular coagulation. Compositions comprising the polypeptides in a suitable pharmaceutical carrier are also provided.

Abstract: A peptide comprising at least the following amino acid sequence:Lys Xa1 Phe Lys Arg Ile Val Xa2 Arg Ile Xaa Xa2 Phe Leu Arg Xa2 Leu Val (SEQ ID NO: 1)wherein, Xa1 represents a hydrophobic amino acid residue, each of Xa2 independently represents a hydrophilic amino acid residue, and Xaa represents an arbitrary amino acid residue;an antimicrobial agent, a medicine including a bacterial infection-treating agent and an endotoxin shock suppressant which each comprise the peptide as an active ingredient; and an endotoxin-removing agent comprising the peptide immobilized to an insoluble carrier.