Summary of immune responses induced by vaccination with combination vaccines.

a<p>The responses to the combination vaccines have been scored on a 4-point scale from undetectable to statistically equivalent to viral infection: no response (-); weak response (+); moderate response (++); equivalent to viral infection (+++).</p><p>Summary of immune responses induced by vaccination with combination vaccines.</p

Influenza epitope-specific CD8⁺ T cells in the lungs of vaccinated mice after recall by viral challenge.

<p>Mice were immunised once by the i.n. (A), s.c. (B) or i.m. (C) routes with 10 nmol lipopeptide (LP), 10 or 0.3 µg of HA as split virus (SV) or combinations of these as indicated (+). Controls were infected with 10^4.5 pfu of virus (Inf) or PBS. One month post immunisation, mice were challenged by the i.n. route with 10^4.5 pfu of virus. The IFN-γ secreting CD8⁺ T cells in the lungs 5 days later that were specific for the TYQRTRALV epitope were enumerated by ICS. Data are presented as the total CD8⁺ T cells producing IFN-γ in response to peptide stimulation minus the number detected in the absence of stimulation. Bars represent the geometric mean for the group (n = 5) and error bars indicate the standard error.</p

Pulmonary viral clearance after vaccination with lipopeptide or split virus vaccines.

<p>Mice were immunised by the i.n. (red), s.c. (blue) or i.m. (green) route with incremental doses of either lipopeptide (A) or split virus (B) on one occasion. One month post-immunisation, mice were challenged by the i.n. route with 10^4.5 pfu of virus. The lungs were removed 5 days later and pulmonary viral titre determined by plaque formation. Symbols represent the geometric mean for the group (n = 5) and error bars indicate the standard error.</p

Viral clearance and antibody titre induced by immunisation with the low dose combination vaccine and its individual components.

<p>Mice were immunised once by the i.n. (squares), s.c. (triangles) or i.m. (circles) routes with 10 nmol lipopeptide (LP), 0.3 µg of HA as split virus (SV) or a combination of both components as indicated (+) or infected with 10^4.5 pfu of virus (Inf). Control mice received PBS. One month post-immunisation, mice were challenged by the i.n. route with 10^4.5 pfu of virus, lungs were removed 5 days later and pulmonary viral titre determined by plaque formation (A). Mice were bled prior to challenge, and the virus-specific antibody response in sera measured by ELISA (B). Symbols represent the titres for individual mice, and the line indicates the geometric mean for the group (n = 5). The numbers above the data sets refer to the average percentage decrease in viral load compared to PBS control mice.</p

HI titer of serum from mice vaccinated by the i.n. route.

<p>Mice were immunized once with PBS, 10 nmol lipopeptide (LP), 10 or 0.3 µg of HA as split virus (SV) or combinations of these as indicated (+) by the i.n. route. Sera sampled one month later were tested for HI activity against the homologous virus. Bars represent the mean HI titers for groups of 5 mice and error bars indicate the standard error of the mean. Titers of <10, observed for all animals in the PBS and lipopeptide alone groups are designated as 10 for the purposes of statistical analysis.</p

Viral clearance and antibody titre induced by immunisation with the high dose combination vaccine and its individual components.

<p>Mice were immunised once by the i.n. (squares), s.c. (triangles) or i.m. (circles) routes with 10 nmol lipopeptide (LP), 10 µg of HA as split virus (SV) or a combination of both components as indicated (+) or infected with 10^4.5 pfu of virus (Inf). Control mice received PBS. One month post-immunisation, mice were challenged by the i.n. route with 10^4.5 pfu of virus, lungs were removed 5 days later and pulmonary viral titre determined by plaque formation (A). Mice were bled prior to challenge, and the virus-specific antibody response in sera measured by ELISA (B). Symbols represent the titres for individual mice, and the line indicates the geometric mean for the group (n = 5). The numbers above the data sets refer to the average percentage decrease in viral load compared to PBS control mice.</p

Emergence and Spread of SARS-CoV-2 Lineages B.1.1.7 and P.1 in Italy.

Italy's second wave of SARS-CoV-2 has hit hard, with more than three million cases and over 100,000 deaths, representing an almost ten-fold increase in the numbers reported by August 2020. Herein, we present an analysis of 6515 SARS-CoV-2 sequences sampled in Italy between 29 January 2020 and 1 March 2021 and show how different lineages emerged multiple times independently despite lockdown restrictions. Virus lineage B.1.177 became the dominant variant in November 2020, when cases peaked at 40,000 a day, but since January 2021 this is being replaced by the B.1.1.7 'variant of concern'. In addition, we report a sudden increase in another documented variant of concern-lineage P.1-from December 2020 onwards, most likely caused by a single introduction into Italy. We again highlight how international importations drive the emergence of new lineages and that genome sequencing should remain a top priority for ongoing surveillance in Italy