Use of microparticles combined with submicron oil-in-water emulsions
Compositions are provided which include biodegradable microparticles with entrapped or adsorbed antigens, in combination with submicron oil-in-water emulsions. Also provided are methods of immunization which comprise administering to a vertebrate subject (a) a submicron oil-in-water emulsion, and (b) a therapeutically effective amount of a selected antigen entrapped in a microparticle.
1. A method of inducing an immune response which comprises administering to a vertebrate subject (a) a submicron oil-in-water emulsion immunological adjuvant, and (b) a therapeutically effective amount of a selected antigen entrapped in, or adsorbed to, a biodegradable microparticle, wherein the submicron oil-in-water emulsion comprises 1% to 12% by volume of a non-toxic metabolizable oil and 0.02% to 2.5% (w/v) of emulsifying agent.
2. The method of claim 1 , wherein the microparticle is formed from a poly(α-hydroxy acid) selected from the group consisting of poly(L-lactide), poly(D,L-Iactide) and poly(D,L-lactide-co-glycolide).
3. The method of claim 2 , wherein the microparticle is formed from poly(D,L-lactide-co-glycolide.
4. The method of claim 1 , wherein the submicron oil-in-water emulsion comprises 4-5% w/v squalene, 0.25-0.5% w/v polyoxyethylene sorbitan monooleate, and 0.5% w/v sorbitan trioleate, and optionally, N-acetylmuramyl-L-alanyl-D-isogluatminyl-L-alanine-2-(1′-2′-dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine.
5. The method of claim 1 , wherein the selected antigen is a viral antigen.
6. The method of claim 5 , wherein the selected antigen is gp 120.
7. The method of claim 5 , wherein the selected antigen is p24gag.
8. The method of claim 5 , wherein the selected antigen is hepatitis C virus E2.
9. The method of claim 1 , wherein the selected antigen is entrapped in the microp article.
10. The method of claim 1 , wherein the selected antigen is adsorbed to the microparticle.
11. The method of claim 1 , wherein the submicron oil-in-water emulsion is administered prior to the microparticle.
12. The method of claim 1 , wherein the submicron oil-in-water emulsion is administered subsequent to the microparticle.
13. The method of claim 1 , wherein the submicron oil-in-water emulsion is administered substantially concurrently with the microparticle.
14. The method of claim 1 , wherein the submicron oil-in-water emulsion further comprises N-acetylmuramyl-L-alanyl-D-isogluatminyl-L-alanine-2-(1′-2′-dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine.
15. the method of claim 4 , wherein the submicron oil-in-water emulsion further comprises N-acetylmuramyl-L-alanyl-D-isogluatminyl-L-alanine-2-(1′-2′-dipalmitoyl-sn-glycero-3-hydroxyphosphoryloxy)-ethylamine.