Agroinfiltration of plant tissues for production of high‐value recombinant proteins: an alternative to production in transgenic crops

Agrobacterium tumefaciens mediated transient expression of plant cell wall‐degrading enzymes in detached sunflower leaves

“…A. tumefaciens ‐mediated transient expression is very different from stable expression and has many advantages for specific applications . For example, there is no need to generate stable transgenic plants or to perform selection of stable integration, as untransformed plants can be used as hosts for transient expression.…”

“…13,14 A. tumefaciens-mediated transient expression is very different from stable expression and has many advantages for specific applications. 15 For example, there is no need to generate stable transgenic plants or to perform selection of stable integration, as untransformed plants can be used as hosts for transient expression. Transient gene expression is usually much greater than that of transgenic plants due to a burst of gene expression from transferred T-DNA prior to stable integration.…”

High‐Level Transient Production of a Heterologous Protein in Plants by Optimizing Induction of a Chemically Inducible Viral Amplicon Expression System

“…However, transient expression systems are now being investigated for production of heterologous proteins as they offer several advantages over production in transgenic plants including a short time frame from gene to expression of the recombinant protein (5,6), higher recombinant protein yields due to a burst of gene expression (7), the ability to co-infiltrate and simultaneously produce multiple recombinant proteins (8), and the ability to use on hand biomass for large-scale production (9), all while alleviating environmental and regulatory concerns associated with the production of transgenic plants. Transient production can also be performed in harvested plant tissue to produce high-value proteins within a contained facility and eliminate exposure of vectors to the environment (6). Additionally, transient expression can utilize viral expression systems, whereas these systems have been problematic in transgenic plants which can limit viral replication via post-transcriptional gene silencing mechanisms (10,11).…”

“…Transient expression systems offer several advantages over production in transgenic plants including a short timeframe from gene to expression of the recombinant protein, 9,10 higher recombinant protein yields due to a burst of gene expression, 11 the ability to co-infiltrate and simultaneously produce multiple recombinant proteins, 12 and the ability to use on hand biomass for large-scale production, 13 while alleviating environmental and regulatory concerns associated with the production of transgenic plants since transient production can be performed on harvested nontransgenic plant tissue to produce heterologous proteins within a contained facility and eliminate exposure of recombinant material to the environment. 9 Since transient production uses nontransgenic plant tissue, the biomass can be easily scaled up by growing more plants in the field. Additionally, transient expression can utilize inducible promoters and viral expression systems which have been shown to increase product titers, the latter of which has been used for production of many industrially significant proteins including biologically functional human growth hormone, 14 antigens for plague 15 and tuberculosis, 16 and fully assembled monoclonal IgG antibodies.…”

Transient Virus Expression Systems for Recombinant Protein Expression in Dicot- and Monocotyledonous Plants

“…The co expression of silencing suppressor proteins has been shown to be a key factor for optimized yields [57][58][59]. Such methods have been used to produce a range of biopharmaceutical proteins [60][61][62] and offer strategies to modify the plant enzymatic machinery, producing more stable and "human" like recombinant proteins, including glycan structures [34,60] which will be discussed later in this review.…”