HEV Mosaic
Description
Product Specs
Product Science Overview
Hepatitis E virus (HEV) is a significant cause of acute hepatitis worldwide, particularly in developing countries. It is a single-stranded, positive-sense RNA virus that primarily spreads through the fecal-oral route, often via contaminated water. HEV infections can lead to severe liver disease, especially in pregnant women and immunocompromised individuals .
HEV belongs to the Hepeviridae family and has four primary genotypes that infect humans: HEV-1, HEV-2, HEV-3, and HEV-4. Genotypes 1 and 2 are typically found in developing countries and are associated with large outbreaks, while genotypes 3 and 4 are zoonotic and can be transmitted from animals to humans .
The development of recombinant HEV vaccines has been a significant advancement in preventing HEV infections. These vaccines are based on the HEV open reading frame 2 (ORF2) capsid protein, which is crucial for the virus’s ability to infect host cells. The ORF2 protein is often produced using recombinant DNA technology in various expression systems, such as Escherichia coli .
Mosaic recombinant HEV vaccines are designed to enhance the immune response by incorporating multiple epitopes from different HEV genotypes. This approach aims to provide broader protection against various HEV strains. The mosaic design involves creating chimeric proteins that combine antigenic regions from different HEV genotypes, thereby eliciting a more robust and cross-protective immune response .
The preparation of mosaic recombinant HEV vaccines involves several steps:
- Gene Cloning: The genes encoding the desired antigenic regions from different HEV genotypes are cloned into suitable expression vectors.
- Protein Expression: The recombinant vectors are introduced into expression systems, such as E. coli, to produce the chimeric proteins.
- Protein Purification: The expressed proteins are purified using techniques like affinity chromatography to obtain high-purity antigens.
- Formulation: The purified proteins are formulated with adjuvants to enhance the immune response and stability of the vaccine .
Clinical trials have demonstrated the efficacy and safety of recombinant HEV vaccines. For instance, a study showed that a recombinant HEV vaccine based on the ORF2 protein had an efficacy of 86.8% over a 4.5-year period . The vaccine was well-tolerated, with no significant adverse effects reported .
