A COMPARATIVE-STUDY OF THE UTILIZATION OF ETHER-LINKED AND ESTER-LINKED PHOSPHOLIPID-CONTAINING LIPOSOMES BY J774.E1 MACROPHAGE CELL-LINE INFECTED WITH LEISHMANIA-MEXICANA-MEXICANA AMASTIGOTES

The macrophage cell-line 5774.E1 and Leishmania m. mexicana infection was used to investigate the uptake of liposomes, which differed in the ir bulk phospholipid: ester- or ether-analogue of phosphatydilcholine (PC). The receptor-mediated uptake of both species of liposomes, conta ining native or acetylated LDL as ligands was also evaluated. Uninfect ed and infected 5774.E1 cell-line accumulated more ester- and ether-li posomes alone than mixed type (50:50, ester/ether). The utilization wa s significantly enhanced when both types of liposomes contained native LDL. The highest uptake was recorded for liposomes bearing acetylated LDL by infected 5774.E1 cells. Accumulation of ester- and ether-lipos omes with the same ligand was not markedly affected by different chemi cal nature of PC. Finally, ether-liposomes alone possessed certain act ivity against Leishmania m. mexicana amastigotes. The results presente d here demonstrated the usefulness of ether-liposomes with specific li gands in site-specific delivery of antileishmanial compounds in vitro.