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A Potent #Pandemic Avian #Influenza Virus #Vaccine Based on a 4th Generation Fully Deleted #Adenoviral #Vector

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By G.M.

Abstract

The GreVac system was developed as a fast and flexible plug-and-play vaccine platform based on an architecture of fully deleted (fd) helper virus-independent (hi) adenoviral (Ad) vectors. The present study established the potency of the GreVac technology. It demonstrated that the GreFluVie5 vaccine fully protected mice against lethal challenges with the A/Vietnam/1203/2004 (H5N1) pandemic avian influenza virus. The GreFluVie5 vector delivered a transgene expression cassette for the H5 hemagglutinin and N1 neuramidase influenza genes. Its fd Ad genome was carried in a capsid of the human serotype 5 (Ad5). The efficacies of three different doses and three different administration routes were compared in the mouse model. The vaccine fully protected animals against viral challenges with the wild-type A/Vietnam/1203/2004 virus, whose replication in the recipients' lungs was terminated. It induced strong immune responses. The present experiments also revealed that the intra muscular (i.m.) delivery route of GreFluVie5 was more efficient than sub cutaneous (s.c.) or intra nasal (i.n.) ones. Based on the results of this trial and GreVac's intrinsic versatility and fast development time, we believe that this platform is ideally suited to swiftly deliver powerful vaccines to infectious diseases with high eruption potentials.

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2024.12.30.630761v1

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