Immunisation of large mammals with low doses of RNA
RNA encoding an immunogen is delivered to a large mammal at a dose of between 2 μg and 100 μg. Thus the invention provides a method of raising an immune response in a large mammal, comprising administering to the mammal a dose of between 2 μg and 100 μg of immunogen-encoding RNA. Similarly, RNA encoding an immunogen can be delivered to a large mammal at a dose of 3 ng/kg to 150 ng/kg. The delivered RNA can elicit an immune response in the large mammal.
1. A method of eliciting an antibody response against a coronavirus spike polypeptide immunogen by an immune system in a large mammal, the method comprising administering intramuscularly to the large mammal at least two unit doses; each unit dose comprising a composition comprising liposomes and messenger ribonucleic acid (mRNA) molecules; the mRNA molecules comprising a poly-adenosine monophosphate (poly(A)) tail and a sequence that encodes the coronavirus spike polypeptide immunogen; each unit dose comprising between 2 μg and 100 μg of the mRNA molecules; the at least two unit doses being sequential and administered at least 1 week apart; the administering comprising contacting the composition with skeletal muscle; the liposomes comprising a cationic lipid: the cationic lipid comprising a tertiary amine; the liposomes encapsulating at least half of the mRNA molecules; and the large mammal being a human or a cow.
2. The method of claim 1 , the mRNA molecules comprising a 5′ cap nucleoside, a first 5′ ribonucleoside, and a triphosphate bridge: the 5′ cap nucleoside being linked 5′-to-5′ to the first 5′ ribonucleoside by the triphosphate bridge: the 5′ cap nucleoside optionally being a 7-methylguanosine; and the large mammal being the human.
3. The method of claim 1 , at least 80% of the liposomes having diameters from 20 nm to 220 nm.
4. The method of claim 2 , the liposomes further comprising: i) an anionic phospholipid or a zwitterionic phospholipid and ii) cholesterol.
5. The method of claim 3 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol; and the large mammal being the human.
6. The method of claim 5 comprising administering to the human at least three unit doses.
7. The method of claim 2 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.
8. The method of claim 7 comprising administering to the human at least three unit doses.
9. The method of claim 1 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol; and the large mammal being the human.
10. The method of claim 9 comprising administering to the human at least three unit doses.
11. The method of claim 2 , the mRNA molecules comprising a modified nucleotide.
12. The method of claim 11 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.
13. The method of claim 12 comprising administering to the human at least three unit doses.
14. The method of claim 11 , the modified nucleotide being a modified pyrimidine nucleotide.
15. The method of claim 14 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.
16. A method of eliciting an antibody response against a coronavirus spike polypeptide immunogen by an immune system in a large mammal, the method comprising administering intramuscularly to the large mammal at least two unit doses, each unit dose comprising a composition comprising liposomes and mRNA molecules; the mRNA molecules comprising a poly(A) tail and a sequence that encodes the coronavirus spike polypeptide immunogen; each unit dose comprising between 0.5 μg and 1.5 μg of the mRNA molecules per kg of the body mass of the large mammal; the at least two unit doses being sequential and administered at least 1 week apart; the administering comprising contacting the composition with skeletal muscle; the liposomes comprising a cationic lipid: the cationic lipid comprising a tertiary amine; the liposomes encapsulating at least half of the mRNA molecules; and the large mammal being a human or a cow.
17. The method of claim 16 , the mRNA molecules comprising a 5′ cap nucleoside, a first 5′ ribonucleoside, and a triphosphate bridge: the 5′ cap nucleoside being linked 5′-to-5′ to the first 5′ ribonucleoside by the triphosphate bridge: the 5′ cap nucleoside optionally being a 7-methylguanosine; and the large mammal being the human.
18. The method of claim 16 , at least 80% of the liposomes having diameters from 20 nm to 220 nm.
19. The method of claim 17 , the liposomes further comprising: i) an anionic phospholipid or a zwitterionic phospholipid and ii) cholesterol.
20. The method of claim 18 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol; and the large mammal being the human.
21. The method of claim 20 comprising administering to the human at least three unit doses.
22. The method of claim 17 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.
23. The method of claim 22 comprising administering to the human at least three unit doses.
24. The method of claim 16 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol; and the large mammal being the human.
25. The method of claim 24 comprising administering to the human at least three unit doses.
26. The method of claim 17 , the mRNA molecules comprising a modified nucleotide.
27. The method of claim 26 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.
28. The method of claim 27 comprising administering to the human at least three unit doses.
29. The method of claim 26 , the modified nucleotide being a modified pyrimidine nucleotide.
30. The method of claim 29 , the liposomes further comprising 1,2-distearoyl-sn-glycero-3-phosphocholine and cholesterol.