2017-03-07. BLASTP Comparison of A/Michigan/45/2015 (recommended by WHO) and A/Montana/04/2016 (recommended by FutureFlu) showing 100% identities and zero gaps proving that the two vaccines are identical
Antigenic Drift between A/Michigan/45/2015 and representative members of Clade 6B.2
A/Brisbane/294/2016 | A/HongKong/90/2016 | A/Israel/Q-504/2015 | A/SouthAustralia/121/2016
> N101S N101S N101S N101S
> V169T V169T V169T V169T
> N179S N179S N179S N179S
> V190I V190I V190I V190I
> T233I T233I T233I T233I
A278S A278S A278S
> E508G E508G E508G E508G
> D518E D518E D518E D518E
The computed antigenic distance is less that 0.25 Antigenic Units, which is within acceptable limit. N101S, V169T, N179S, V190I, T233I, E508G and D518E, highlighted by the chevrons, are the major mutational differences between the two Clades. Of these, N179S is significant because it eliminates a potential N-linked glycosylation site. The amino acid pattern of a potential glycosylation site is NXS/T or NXXS/T. The mutation replaces the arginine with serine, thus disrupting the pattern.
2017-03-01. Comparison of Clade 6B.1 with A/California/07/2009 and A/Montana/04/2016
Synonymous differences between the genomes of A/Michigan/45/2015 (MI15) and A/Montana/04/2016 (MT16)
Coordinate MI15 MT16 Coded
Codon Codon Amino Acid
047 AAC AAT N
131 GAG GAA E
177 CTT CTC L
313 CCG CCA P
317 GGA GGG G
337 GTT GTC V
526 ATT ATC I
554 TGC TGT C
All coordinates (i.e. amino acid or nucleotide locations in a sequence) in the following discussion are in the HA1 frame of reference. Hemagglutinin comprises 566 peptides, which are signal peptide (17 aa) + HA1 (327 aa) + HA2 (222 aa), where aa = amino acids.
This research has focused on the HA1 segment because it contains the receptor-binding and antigenic domains and is therefore, the target of all flu vaccines. HA1 and HA2 are hinged by an alpha-helical coiled coil and linked by two cysteine residues, forming intramonomer disulfide bridges in a prestressed hairpin conformation. The cytoplasmic proteasomes and proton pumps in the membrane of the endocytic vesicles (containing the virus) lower the endosomal pH, cleaving the HA1-HA2 hinge, disassociating HA1 from HA2 and making it virulent.
The mutations in the following text are listed in the customary notation. For example, S101N refers to the mutation from S (serine) to N (asparagine) at the coordinate 101 of the HA1 segment.
2017-04-20. Antigenic Drift between A/Michigan/45/2015 and Clade 6B.2
CA09: A/California/07/2009 like, current vaccine
MT16: A/Montana/04/2016 like, proposed by FutureFlu
HI Titers computed with the Antigenic Prediction Model:
Clade 6B.1 antigen against CA09 antiserum = 1,142
Clade 6B.1 antigen against MT16 antiserum = 2,616
Autologous titer = 2,560
Antigenic drifts between Clade 6B.1 and
● CA09 = |1 - log2 (1142) / log2 (2560)| = 1.03 AU
● MT16 = |1 - log2 (2616) / log2 (2560)| = 0.03 AU
With an antigenic distance greater than 1 Antigenic Unit, CA09 has drifted from the prevalent strains, while MT16 is highly aligned with Clade 6B.1 (= 0.03 AU). It is also evident in the phylogenetic tree of the clade (on left) including the vaccine candidates (shown in yellow).
2017-09-05: According to the WHO Weekly Report dated 04 Sep 2017, Type A influenza (H1N1pdm and H3N2) continues to dominate the flu sickness with 89.2% of the reported cases. FutureFlu is extending the Prediction Model to H3N2, with emphasis on epitopes A-E in the H1 HA molecule? More ...
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This website is currently tracking the H1N1pdm strain of the influenza virus. Extending the project to other three strains of the quadrivalent vaccine recommended by the World Health Organimzation, namely, H3N2, B/Victoria and B/Yamagata are works-in-progress.