INTERACTIONS BETWEEN BACTERIAL PYROGEN AND PROTEOLIPID EXTRACTED FROM THE CEREBRUM (III) VARIATION IN AFFINITY OF PROTEOLIPID PROTEINS DERIVED FROM RABBIT, RAT AND CHICKEN CEREBRUMS TO BACTERIAL PYROGEN

We undertook comparative studies on the binding of cerebral proteolipids to LPS using rabbits, rats and chickens in order to clarify the differences in inactivating effects of proteolipids from these three sources on the pyrogenicity of LPS. The Sephadex LH-20 column elution profiles of lipid phosphorus and cerebrosides were not significantly different for the three sources of proteolipid, but a larger amount of proteolipid-protein possessing LPS pyrogenicity inactivating potency was eluted with chloroform(C)/methanol(M) (4:1) in rats and chickens than in rabbits. A complex of proteolipid-protein with LPS was obtained in C effluent from incubation mixtures of rat and chicken proteolipids with LPS, corresponding to our previous observation with rabbit proteolipid. The increasing order of binding capacity of the proteolipids derived from the three species was as follows: chicken, rat and rabbit, which was in parallel with pyrogenic inactivating potency. From these data, we suggest that the difference in pyrogenic inactivating potency among the proteolipids of some species depnds on the difference in binding capacity of the proteolipids to LPS or probably lipid A.