Study of the effects of liposomal amphotericin B on Candida albicans, Cryptococcus neoformans, and erythrocytes by using small unilamellar vesicles prepared from saturated phospholipids.
We compared the anticellular effects of liposomal amphotericin B (AmB) formed from AmB and small unilamellar vesicles. The small unilamellar vesicles with or without cholesterol were prepared from three L-alpha-phosphatidylcholines with saturated acyl chains of different lengths: distearoyl (C18), dipalmitoyl (C16), and dimyristoyl (C14). We found that the anticellular potency of liposomal AmB, compared with that of free AmB, decreased with decreasing length of the acyl chain of the phospholipid and increased with the addition of cholesterol. In a parallel study (S. Jullien, A. Vertut-Croquin, J. Brajtburg, and J. Bolard, Anal. Biochem. 172:197-202, 1988), we found that binding of AmB to vesicles decreased with increasing length of the acyl chain of the phospholipid and decreased with the addition of cholesterol. We conclude that the anticellular effects of liposomal AmB preparations are due to the levels of AmB remaining free (unbound to the lipids) in these preparations.
Jullien
S
S
Laboratoire de Physique et Chimie Biomoleculaire (Unité Associée Centre National de la Recherche Scientifique, no. 198), Université Pierre et Marie Curie, Paris, France.
Contrepois
A
A
Sligh
J E
JE
Domart
Y
Y
Yeni
P
P
Brajtburg
J
J
Medoff
G
G
Bolard
J
J
D000666:Amphotericin B / Q000008:administration & dosage / Q000494:pharmacology*; D002176:Candida albicans / Q000187:drug effects*; D002463:Cell Membrane Permeability; D002784:Cholesterol / Q000032:analysis; D003454:Cryptococcus / Q000187:drug effects*; D003455:Cryptococcus neoformans / Q000187:drug effects*; D004912:Erythrocytes / Q000187:drug effects*; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D066298:In Vitro Techniques; D008081:Liposomes; D008297:Male; D010743:Phospholipids / Q000032:analysis*; D011188:Potassium / Q000097:blood; D013329:Structure-Activity Relationship
D006454:Hemoglobins; D008081:Liposomes; D010743:Phospholipids; D000666:Amphotericin B; D002784:Cholesterol; D011188:Potassium