TOXICITY OF LIPOSOMES CONTAINING LOW MOL-PERCENT OF DIENOYL PHOSPHOCHOLINE TO BLOOD - USE OF CARBOXYMETHYL CHITIN TO REDUCE TOXICITY

Toxic effects of liposomes composed of the synthetic lipid, (octadeca- 2,4-dienoyl)-sn-glycero-3-phosphocholine (C(18)DENPC) and cholesterol (Cho) were studied. In the present work, we have explored, 1) fusion b etween C(18)DENPC/Cho-liposomes and erythrocyte ghost (EG) membranes w ith resonance energy transfer assay, 2) hemolysis induced by C(18)DENP C/Cho-liposomes, and 3) turbidity changes in native plasma on contact with C(18)DENPC/Cho-liposomes, in the presence or absence of carboxyme thyl chitin (CM-chitin). In the absence of CM-chitin, extents of fusio n, hemolysis and turbidity changes in native plasma increased with the decrease in C(18)DENPC content. In the presnce of CM-chitin at a conc entration of 10(-3) or 10(-2)% (w/v), fusion of C(18)DENPC/Cho-lipasom e with EG was inhibited. Extents of hemolysis and turbidity changes in native plasma induced by C(18)DENPC/Cho-liposomes were reduced depend ing upon CM-chitin concentration.