Norovirus derived immunogenic compositions and methods
The invention relates to chimeric norovirus VP1 proteins containing the S-domain of VP1 of a first norovirus strain and a P-domain that contains at least a portion of the P-domain of VP1 of a second norovirus strain. The invention also relates to nucleic acids that encode the chimeric VP1 proteins, virus-like particles that contain a chimeric norovirus VP1 protein, and to immunogenic compositions.
1. A method of producing a chimeric norovirus VP1 protein or norovirus virus like particles (VLPs) comprising the chimeric norovirus VP1 protein, the method comprising
culturing a recombinant host cell comprising a recombinant nucleic acid encoding a chimeric norovirus viral protein 1 (VP1) comprising an S-domain of the VP1 from a first norovirus strain and a P-domain of the VP1, wherein all or a portion of the P-domain is from a second norovirus strain, under conditions suitable for the expression of the recombinant nucleic acid and
obtaining the chimeric VP1 protein or the VLPs from the culture, wherein the VP1 protein has the formula:
A-S-L-P-B
wherein
A and B are independently absent or comprise any desired amino acid sequence;
S is the S-domain of VP1 from a first norovirus strain;
P is a norovirus VP1 P-domain; wherein at least a portion of the P-domain is from a second norovirus strain;
L is absent or a linker peptide selected from the group consisting of
a linker peptide of the VP1 from the first norovirus strain, from the second norovirus strain, or from a third norovirus strain;
a polyglycine linker of formula (Gly)n wherein n=2, 3, 4, 5, 6, 7, 8, 9, 10 or more (SEQ ID NO:5);
a linker of formula (GGGS)n wherein n=1, 2, 3 or 4 (SEQ ID NO:6); and
a charged linker of formula (SRSK)n wherein n=1, 2, 3 or 4 (SEQ ID NO:7).
2. The method of claim 1 , wherein the culturing comprises maintaining the recombinant host cell under conditions suitable for formation of VLPs.
3. The method of claim 1 , further comprising isolating the chimeric norovirus VP1 protein or VLPs from the culture media or the recombinant host cells or from both the culture media and the recombinant host cells.
4. The method of claim 3 , wherein VLPs are isolated.
5. The method of claim 4 , wherein the VLPs are isolated using a sucrose cushion or sucrose gradient.
6. The method of claim 1 , wherein the chimeric norovirus VP1 self-assembles into virus like particles (VLPs).
7. The method of claim 1 , wherein the host cell is selected from the group consisting of insect cells, mammalian cells, avian cells, bacteria, yeast cells, Tetrahymena cells and combinations thereof.
8. The method of claim 1 , wherein the chimeric norovirus VP1 is in the form of at least 50% purified VLPs.