spleen cells from germfree rats , conventionally reared rats , and gnotobiotic rats associated with two pseudomonas species gave no positive blastogenic response when incubated with each of four lipopolysaccharide ( lps ) preparations from escherichia coli , with glycolipid extracted from salmonella minnesota r595 or with s. minnesota r595 lipid a .
C0023810
lipopolysaccharide
C0023767
lipid a