Type |
Whole plants
|
Obembe et al. 2011 / Drake et al. 2017 |
Stable nuclear transformation
|
Key Features |
Stable incorporation of exogenous genes into the nuclear genome |
Stable inheritance of transgenes in successive generations |
Used to obtain the majority of transgenic plants until today |
Utilized commercially since 2014 in Japan by the company Hokusan for the production of interberry-alpha, a recombinant canine interferon-alpha produced in transgenic strawberry for the treatment of periodontal disease in dogs |
Advantages |
Transmission of new characters as traits inheritable to the progeny |
High scalability |
Disadvantages |
Possibility of undesirable crosses in some species |
Long cycle of production of some plant species |
Usually poor levels of transgene expression |
Type |
Whole plants
|
Meyers et al. 2010MEYERS B, ZALTSMAN A, LACROIX B, KOZLOVSKY SV and KRICHEVSKY A. 2010. Nuclear and plastid genetic engineering of plants: Comparison of opportunities and challenges. Biotechnol Adv 28: 747-756.
|
Stable plastidial transformation |
Key Features |
Stable and simultaneous transformation of numerous copies of the plastidial genome |
Exclusively maternal inheritance in many species |
Advantages |
Natural biocontainment |
Minimizing gene flow by out-crossing |
High levels of expression (up to 70% TSP) |
Disadvantages |
Limited to few species: tomato, lettuce, soybeans and eggplant. |
Routine transformation of tobacco only |
Variable protein stability |
Type |
Plant cell-suspension cultures
|
Franconi et al. 2010FRANCONI R, DEMURTAS OC and MASSA S. 2010. Plant-derived vaccines and other therapeutics produced in contained systems. Expert Rev Vaccines 9: 877-892. / Drake et al. 2017 |
Key Features |
Undifferentiated aggregates of plant cells dispersed and propagated in liquid medium |
System used for the production of the first PMP to achieve commercial production status by the FDA, in 2012: Elelyso, the replacement enzyme glucocerebrosidase from the Israeli company Protalix, in addition to the commercial chicken vaccine against Newcastle disease virus (NDV) from Dow Agroscience |
Advantages |
Fast, relatively inexpensive and high level of containment |
Usually high purity production and low downstream processing costs when the PMP is secreted into the culture medium |
Homogeneity of production |
Low N-glycans addition heterogeneity |
Disadvantages |
Need for sterile production conditions |
Decreased levels of protein biosynthesis in stationary phase, due to proteolytic activity |
Restricted to just a few crops such as tobacco, Arabidopsis, rice and carrots |
Type |
Transient expression systems
|
Regnard et al. 2010REGNARD GL, HALLEY-STOTT RP, TANZER FL, HITZEROTH II and RYBICKI EP. 2010. High level protein expression in plants through the use of a novel autonomously replicating geminivirus shuttle vector. Plant Biotechnol J 8: 38-46./ Loh et al. 2017 |
Agroinfiltration method
|
Key Features |
Infiltration of tobacco leaves by suspension of Agrobacterium tumefaciens cells |
Advantages |
Transference of bacterial T-DNA to a high number of leaf cells |
Fast |
High expression. levels. |
Possibility of producing clinical grade pharmaceuticals |
Disadvantages |
Rapid decay of gene expression after peak expression. |
Inability to transfer transgene to progeny |
Type |
Virus infection method
|
McCormick et al. 2008MCCORMICK AA et al. 2008. Plant-produced idiotype vaccines for the treatment of non-Hodgkin’s lymphoma: Safety and immunogenicity in a phase I clinical study. Proc Natl Acad Sci U S A 105: 10131-10136. / Marsian and Lomonossoff 2016MARSIAN J and LOMONOSSOFF GP. 2016. Molecular pharming—VLPs made in plants. Curr Opin Biotechnol 37: 201-206.
|
Key Features |
Non-integrative method |
Based on the use of plant viruses, such as Tobacco Mosaic Virus (TMV) and Potato Virus X (PVX), as infectious carriers of transgenes |
Used to infect tobacco |
Used by the Large Scale company to obtain vaccines against B-cell non-Hodgkin’s lymphoma |
Advantages |
Fast, scalable and capable of obtaining high levels of recombinant protein biosynthesis |
Disadvantages |
Restricted to tobacco |
Need for immediate processing due to protein instability |
Type |
MagnifectionTM
|
Gleba et al. 2014 |
Key Features |
Platform that combines the characteristics of the methods Agroinfiltration and Virus infection |
Developed by Icon Genetics |
Use of deconstructed viral expression cassettes, lacking protein coat sequences and viral motility proteins sequences |
Systemic delivery of genes is mediated by Agrobacterium |
Advantages |
Improved infectivity |
Increased levels of gene expression and biosynthesis of recombinant proteins greater than 80% TSP |
Fast |
Capable of producing both small molecules, such as vaccine antigens, and large and complex IgGs |
Capable of co-expressing two or several polypeptides simultaneously |
Capable of assembling heterooligomeric proteins |
Ease of manipulation |
Disadvantages |
Restricted to tobacco |
Need for immediate processing due to protein instability |