escherichia coli o26 : b6 lipopolysaccharide , administered at a dose of 1 mg/kg 24 h prior to n. fowleri , afforded some protection for several days after challenge , but by day 8 there was no difference in survival of untreated and endotoxin-treated mice .
C0023810
lipopolysaccharide
C0014264
endotoxin