Preparation and characterization of dipalmitoylphosphatidylcholine liposomes containing interleukin-2.
Human recombinant interleukin-2 (IL-2) has been associated or mixed with small unilamellar vesicles prepared from dipalmitoylphosphatidylcholine (DPPC). Whatever the mode of IL-2 introduction, a considerable proportion of the added protein was associated with the liposomes, as determined by gel filtration and ultrafiltration/centrifugation, suggesting that IL-2 can interact with the lipid bilayer as well as being entrapped within the aqueous phase. Moreover, IL-2 prevented the aggregation/fusion of the vesicles at 4 degrees C. Liposome-associated protein was partially protected from digestion by pepsin, especially at the C-terminal, since no fluorescence emission from the tryptophan in this region was detected in the resulting peptides after separation by HPLC. Such systems could constitute a sustained release form of IL-2 for immunotherapy.
Fleury
L
L
Laboratoire de Pharmacie Galénique, URA CNRS 1218, Chatenay-Malabry, France.
Ollivon
M
M
Dubois
J L
JL
Puisieux
F
F
Barratt
G
G
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry* / Q000494:pharmacology; D002850:Chromatography, Gel; D006801:Humans; D007376:Interleukin-2 / Q000096:biosynthesis / Q000737:chemistry* / Q000494:pharmacology; D008081:Liposomes; D010434:Pepsin A / Q000378:metabolism
D007376:Interleukin-2; D008081:Liposomes; D015060:1,2-Dipalmitoylphosphatidylcholine; D010434:Pepsin A