Article

Incorporation of ovalbumin into ISCOMs and related colloidal particles prepared by the lipid film hydration method.

Drug Delivery Solutions, New Zealand National School of Pharmacy, University of Otago, Dunedin.
International Journal of Pharmaceutics (impact factor: 3.35). 08/2004; 278(2):263-74. DOI:10.1016/j.ijpharm.2004.03.021
Source: PubMed

ABSTRACT The aim of this study was to investigate the incorporation of a model antigen, fluorescently labelled ovalbumin (FITC-OVA), into various colloidal particles including immune stimulating complexes (ISCOMs), liposomes, ring and worm-like micelles, lamellae and lipidic/layered structures that are formed from various combinations of the triterpene saponin Quil A, cholesterol and phosphatidylethanolamine (PE) following hydration of PE/cholesterol lipid films with aqueous solutions of Quil A. Colloidal dispersions of these three components were also prepared by the dialysis method for comparison. FITC-OVA was conjugated with palmitic acid (P) and PE to produce P-FITC-OVA and PE-FITC-OVA, respectively. Both P-FITC-OVA and PE-FITC-OVA could be incorporated in all colloidal structures whereas FITC-OVA was incorporated only into liposomes. The incorporation of PE-FITC-OVA into all colloidal structures was significantly higher than P-FITC-OVA (P < 0.05). The degree of incorporation of protein was in the order: ring and worm-like micelles < liposomes and lipidic/layered structures < ISCOMs and lamellae. The incorporation of protein into the various particles prepared by the lipid film hydration method was similar to those for colloidal particles prepared by the dialysis method (provided both methods lead to the formation of the same colloidal structures). In the case of different colloidal structures arising due to the preparation method, differences in encapsulation efficiency were found (P < 0.05) for formulations with the same polar lipid composition. This study demonstrates that the various colloidal particles formed as a result of hydrating PE/cholesterol lipid films with different amounts of Quil A are capable of incorporating antigen, provided it is amphipathic. Some of these colloidal particles may be used as effective vaccine delivery systems.

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    Article: Straw blood cell count, growth, inhibition and comparison to apoptotic bodies.
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Keywords

colloidal particles
 
colloidal structures
 
different amounts
 
different colloidal structures
 
effective vaccine delivery systems
 
encapsulation efficiency
 
fluorescently labelled ovalbumin
 
hydrating PE/cholesterol lipid films
 
immune stimulating complexes
 
lipid film hydration method
 
lipidic/layered structures
 
model antigen
 
PE/cholesterol lipid films
 
polar lipid composition
 
Quil A. Colloidal dispersions
 
triterpene saponin Quil
 
various colloidal particles
 
various combinations
 
various particles
 
worm-like micelles