Influenza Vaccines Containing Hemagglutinin and Matrix Proteins
An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins. These may be from influenza viruses grown in cell culture rather than eggs. The matrix protein may be a fragment of a full-length viral matrix protein e.g. a matrix M1 fragment with a molecular weight of less than 2 OkDa. The composition may be a subunit vaccine comprising purified surface glycoproteins.
1 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, not as a whole virion, prepared from virus grown in cell culture.
2 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, not as a whole virion, wherein the composition does not contain ovalbumin.
3 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, wherein: the matrix protein has a molecular weight of less than 20 kDa and comprises an amino acid sequence having at least 50% identity to SEQ ID NO: 1.
4 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, wherein: the matrix protein has a molecular weight of less than 20 kDa and comprises an amino acid sequence having at least 75% identity to SEQ ID NO: 28.
5 . A method for preparing an immunogenic composition comprising the steps of:
(i) growing influenza virus in cell culture;
(ii) preparing an antigen composition from the viruses grown in step (i), wherein the antigen composition comprises haemagglutinin and matrix proteins not as a whole virion; and
(iii) combining the antigen composition with a pharmaceutical carrier, to give the immunogenic composition.
6 . The composition or method of any preceding claim, wherein the matrix protein comprises a sequence of 20 amino acids that has at least 80% identity to SEQ ID NO: 2.
7 . The composition or method of any preceding claim, wherein the matrix protein comprises a T cell epitope from influenza virus M1 protein.
8 . The composition or method of any preceding claim, wherein the matrix protein comprises one or the following amino acid sequences: SEQ ID NO: 1; SEQ ID NO: 21; SEQ ID NO: 22; SEQ ID NO: 23; SEQ ID NO: 24; SEQ ID NO: 25; SEQ ID NO: 26; SEQ ID NO: 27.
9 . The composition or method of any preceding claim, wherein the matrix protein has an amino acid sequence which is a fragment of a full-length M1 matrix protein amino acid sequence.
10 . The composition or method of any preceding claim, wherein the matrix protein lacks the N-terminal methionine of the natural M1 sequence.
11 . The composition or method of claim 10 , wherein the matrix protein has a N-terminal sequence SLLTEVETYVLS (SEQ ID NO: 30).
12 . The composition or method of claim 11 , wherein the N-terminal serine of SEQ ID NO: 30 is covalently modified e.g. acetylated.
13 . The composition or method of any one of claims 1 to 9 , wherein the matrix protein has a N-terminal sequence EISLSYSAGALA (SEQ ID NO: 18).
14 . The composition or method of any preceding claim, wherein the composition comprises: (i) a first matrix protein having a N-terminal sequence SLLTEVETYVLS (SEQ ID NO: 30); and (ii) a second matrix protein having a N-terminal sequence EISLSYSAGALA (SEQ ID NO: 18).
15 . The composition or method of any preceding claim, wherein matrix protein is present at a concentration between 1 μg/ml and 15 μg/ml.
16 . The composition or method of any preceding claim, comprising split influenza virus or purified influenza surface antigens.
17 . The composition or method of any preceding claim, wherein the haemagglutinin is from a H1, H2, H3, H5, H7 or H9 influenza A virus subtype.
18 . The composition or method of any preceding claim, wherein the influenza virus proteins is prepared from an influenza virus grown on a culture of a host cell and the composition contains less than 10 ng of cellular DNA from the host cell.
19 . The composition or method of any preceding claim, wherein the composition contains between 0.1 and 20 μg of haemagglutinin per viral strain.
20 . The composition or method of any preceding claim, wherein the composition includes an adjuvant.
21 . The composition or method of claim 20 , wherein the adjuvant comprises one or more aluminium salts.
22 . The composition or method of claim 20 , wherein the adjuvant comprises an oil-in-water emulsion.
23 . An immunogenic composition comprising (i) influenza virus haemagglutinin and matrix proteins, not as a whole virion, and (ii) an adjuvant.
24 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, not as a whole virion, wherein the haemagglutinin has a subtype selected from: H2, H4, H5, H6, H7, H8, H9, H10, H11, H12, H13, H14, H15 or H16.
25 . An immunogenic composition comprising influenza virus haemagglutinin and matrix proteins, wherein the concentration of haemagglutinin in the composition is 29 μg/ml per strain or lower.
26 . An immunological assay for analyzing an influenza vaccine, wherein a sample of the vaccine is analyzed to determine the presence of a fragment of M1 matrix protein.