Spleen transcriptional profiling of Mus musculus BALB/c strain after DNA vaccination against influenza H5N1

Hemagglutinin of the influenza virus is the main external glycoprotein. This very immunogenic protein is the target of the most anti-influenza vaccines. DNA vaccines are new alternative to conventional inactivated ones. Four DNA vaccines were tested. Each tested variant was based on the pCI vector with nucleotide sequence encoding hemagglutinin from A/swan/Poland/305-135V08/2006 (H5N1, clade 2.2). In K3/pCI, GK/pCI and HAneo/pCI the different optimization algorithms of hemagglutinin encoding sequence without amino acids change were tested. In 3NF/pCI the NFkappaB binding sites flanking the expression cassette were included in order to improve the nuclear transfer. Comparative transcriptome analysis of mice vaccinated the following vaccine HAneo/pCI,K3/pCI, GK/pCI or 3NF/pCI versus empty vector demonstrated minor changes in genes expression pattern. Most genes were expressed on the similar level in the vaccinated individuals and in the control mice. Small number of genes in particular variants showed the expression different than in the control mice. In general, the identified genes with the changed expression included some genes involved in metabolic processes and none of them seem to induce any undesirable pathways nor disease. 6-8 weeks female mice BALB/c strain were used in the experiments. Three independent biological replicates of total RNA were isolated for each vaccine variants: HAneo/pCI, K3/pCI and 3NF/pCI and two independent biological replicates of total RNA were isolated from negative control group - empty vector and group GK/pCI. The spleen samples were collected 3 days after the booster DNA vaccination against influenza virus, each of dose was 20ug of plasmid DNA per mouse. Totally, 13 samples of RNA was prepared.