Purification of plant-made human recombinant alpha-1-antitrypsin

摘要

Plants provide a viable option to traditional microbial and mammalian cell culture technologies for production of recombinant proteins, allowing for cost effective, highly scalable and safe production of recombinant therapeutic proteins. Tobacco plants have been widely used to express proteins in their leafy biomass. Tobacco is an efficient expression host since it is a non-feed/food crop and produces a high biomass yield. Viral-based expression vectors cloned into Agrobacterium tumefaciens are very attractive recombinant protein expression tools allowing proteins to be produced to a high level within a short period of time. In the novel chemically inducible viral amplicon expression system referred to as CMViva (Cucumber Mosaic Virus inducible viral amplicon) the open reading frame of the CMV coat protein is replaced with the plant codon optimized gene for the target product. The current research work is focused on human alpha-1-antitripsin (AAT), a 52kDa human glycoprotein produced in the liver and circulated in the blood. AAT deficiency is a genetic disorder which leads to non-smoking related, early onset emphysema and a decline in lung functionality over time. Plasma derived AAT is currently the only FDA approved source, however due to production constraints, safety concerns and cost, alternative recombinant production methods are being investigated.