Similarity of host responses elicited by polysaccharides of animal and plant origin and by bacterial endotoxins.

Ten polysaccharides, isolated from various animal and plant sources, were selected for comparison with 2 bacterial polysaccharides, typical of Gram-negative endotoxins. The tissue sources were: mouse (kidney, liver, lung, stomach, Sarcoma 37, and Carcinoma 241-6); rabbit skin and chick embryo skin; and tangerine and Bryonia root. The bacterial endotoxins were those of S. typhosa and Serr. marcescens. Their relative potency was determined in inducing the following host effects: fever, tolerance to pyrogenic action, leucocytic changes, the Shwartzman reaction, damage to Sarcoma 37, dermal hemorrhagic-necrosis by epinephrine, enhancement of antibody production, and lethality. Some of the polysaccharides were consistently active in all the host reactions studied; except for pyrogenic activity at high dosage, the other polysaccharides were consistently negative throughout. The mouse tissue polysaccharides elicited all the effects studied; in some instances their potency approached those of the bacterial polysaccharides. It is pointed out that elicitation of the above array of biological phenomena, hitherto considered characteristic of bacterial endotoxins, can be obtained with polysaccharides from animal and plant tissues.