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HAV anti-MAP vaccine

After preliminary research followed by bioinformatics we selected four genes from the MAP genome that we believe are critically related to MAP’s disease-causing properties. The DNA of the selected genes was optimized into the form most easily read by the synthetic machinery of human and mammalian cells and strung together to form the single HAV vaccine core. For patient safety reasons, this was further edited to remove any genetic sequences that resembled a mammalian sequence. There are no functional sequences in the HAV vaccine core that match anything in the whole human genome. Working with Oxford University’s Jenner Institute, the HAV core was inserted into replication-defective viral vectors that are readily recognised by the human immune system, such as an adenovirus derived from the common cold virus and modified vaccinia Ankara related to the cowpox virus. While the viral vectors are essential for the delivery of the HAV vaccine, it is the core itself that gives the vaccine its unique anti-MAP activity.

When the vaccine is injected the viral vectors carry the 4 MAP genes into phagocytic and other cells where the core components are expressed and displayed on the cell surface for some weeks mimicking a real MAP infection. The viral vectors also act as powerful adjuvants of the overall immune response. The result is the production of millions of T-lymphocytes and macrophages programmed to recognize the MAP-infected host cells that they then destroy, along with the intracellular MAP load. Such vaccines can be used to treat chronic intracellular infections as well as to prevent them.

The pathogenicity related genes from MAP present in the HAV T-cell vaccine are present in all MAP strains so that the vaccine will be effective against all of them.