RSV F protein compositions and methods for making same
The present invention relates to immunogenic compositions comprising RSV F protein, methods for preparing compositions that contain RSV F protein ecto-domain polypeptides, and to certain engineered RSV F proteins and nucleic acids that encode the engineered RSV F proteins. Compositions prepared using the methods can contain RSV F protein ecto-domain polypeptides in a predominant or single desired form and conformation. The invention also relates to methods for inducing an immune response to RSV F.
1. A respiratory syncytial virus (RSV)-F heterodimer comprising a F1 subunit, a F2 subunit, and an oligomerization domain, wherein:
the F1 subunit comprises an amino acid sequence at least 95% identical to the F1 subunit of SEQ ID NO: 1;
the F2 subunit comprises an amino acid sequence at least 95% identical to the F2 subunit of SEQ ID NO: 1; and
the oligomerization domain is a trimerizing sequence from bacteriophage T4 fibritin comprising amino acid residues 3-29 of SEQ ID NO: 19.
2. The RSV-F heterodimer of claim 1 , wherein the F1 subunit comprises an amino acid sequence at least 95% identical to amino acids 137-574 of SEQ ID NO: 1; and the F2 subunit comprises an amino acid sequence at least 95% identical to amino acids 22 to 109 of SEQ ID NO: 1.
3. The RSV-F heterodimer of claim 1 , wherein the trimerizing sequence from bacteriophage T4 fibritin is attached to a C-terminus of the F1 subunit.
4. The RSV-F heterodimer of claim 3 , wherein the trimerizing sequence is attached to the C-terminus of the F1 subunit with a linker sequence.
5. A RSV-F F1-F2 homotrimer comprising three RSV-F heterodimers of claim 1 .
6. A nucleic acid encoding the RSV-F heterodimer of claim 1 .
7. A vector comprising the nucleic acid of claim 6 .
8. A host cell comprising the vector of claim 7 .
9. A method of making a RSV-F heterodimer comprising a F1 subunit, a F2 subunit, and an oligomerization domain, wherein: the F1 subunit comprises an amino acid sequence at least 95% identical to the F1 subunit of SEQ ID NO: 1; the F2 subunit comprises an amino acid sequence at least 95% identical to the F2 subunit of SEQ ID NO: 1, and the oligomerization domain is a trimerizing sequence from bacteriophage T4 fibritin comprising amino acid residues 3-29 of SEQ ID NO: 19, the method comprising: culturing the host cell of claim 8 and recovering the heterodimer from a culture media.
10. An immunogenic composition comprising the RSV-F heterodimer of claim 1 .
11. The immunogenic composition of claim 10 , further comprising an adjuvant.
12. A method of inducing an immune response to RSV in a subject, the method comprising administering an effective amount of the immunogenic composition of claim 10 to the subject.