Submitted to: Transgenic Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/31/2012
Publication Date: 4/24/2012
Citation: Lowther, W., Yeow, W., Lawrence, S.D. 2012. Expression of biologically active human interferon alpha 2 in aloe vera. Transgenic Research. DOI: 10.1007/s11248-012-9616-0. Interpretive Summary: Efficient production of genetically transformed plants is important to agriculture generally to improve crop plants and it is crucial to scientists to perform experiments to learn how specific genes affect plant function. As a proof of concept, Aloe Vera was transformed with a gene of a high value biomedical product, interferon. Not only was it shown that the product maintained activity, the product remained active after two years of plant growth via budding from the parent plant and it was produced in both the aloe rind and gel. This means that genetically transformed aloe can be propagated and the subsequent plantlets also produce the transgenic protein. This work is the first to transform Aloe Vera with a marketable trait and will benefit growers for high value niche markets.
Technical Abstract: We have developed a system for transgenic expression of proteins in Aloe Vera. Using this approach we have generated plants expressing the human gene interferon alpha 2, IFNa2. IFNa2 is a small secreted cytokine that plays a vital role in regulating the body’s immune response to viral infections as well inhibiting tumor growth and development. Transgenic plants were regenerated from zygotic embryo derived callus and assayed for IFNa2 expression. IFNa2 expression was confirmed using RT-PCR and western blot analysis. Protein was isolated from both the rind as well as the pulp fraction of the aloe shoot and assessed for biological activity both by induction of ISG expression as well as by protection of cells in an antiviral assay. These plants have continued to stably express IFNa2 for more than two years with up to 2x103 IU/gram of fresh weight produced. IFNa2 was also detected in aloes that developed vegetatively from transformed parent plants. The unique shoot anatomy of aloe offers an attractive vehicle for both protein expression and delivery.