Plant molecular farming in the wake of the closure of Medicago Inc

Benvenuto, Eugenio; Broer, Inge; D’Aoust, Marc‐André; Hitzeroth, Inga I.; Hundleby, Penny; Menassa, Rima; Oksman-Caldentey, Kirsi-Marja; Peyret, Hadrien; Salgueiro, S.; Saxena, Pooja; Stander, Jennifer; Warzecha, Heribert; K.‐C., Julian

doi:10.1038/s41587-023-01812-w

Cited by 9 publications

(2 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…While the approval of a plant-made VLP-based COVID-19 vaccine was a huge success for the field, the manufacturing was discontinued in 2023 based on management decisions in the light of changes in the global COVID-19 vaccine demand and market environment. Despite this recent blowback, all these milestones demonstrate the huge potential of plants as bioreactors for biopharmaceutical production ( Benvenuto et al., 2023 ; Eidenberger et al., 2023 ).…”

Section: Introductionmentioning

confidence: 99%

Performance of plant-produced RBDs as SARS-CoV-2 diagnostic reagents: a tale of two plant platforms

Santoni,

Gutierrez-Valdes,

Pivotto

et al. 2024

Front. Plant Sci.

View full text Add to dashboard Cite

The COVID-19 pandemic has underscored the need for rapid and cost-effective diagnostic tools. Serological tests, particularly those measuring antibodies targeting the receptor-binding domain (RBD) of the virus, play a pivotal role in tracking infection dynamics and vaccine effectiveness. In this study, we aimed to develop a simple enzyme-linked immunosorbent assay (ELISA) for measuring RBD-specific antibodies, comparing two plant-based platforms for diagnostic reagent production. We chose to retain RBD in the endoplasmic reticulum (ER) to prevent potential immunoreactivity issues associated with plant-specific glycans. We produced ER-retained RBD in two plant systems: a stable transformation of BY-2 plant cell culture (BY2-RBD) and a transient transformation in Nicotiana benthamiana using the MagnICON system (NB-RBD). Both systems demonstrated their suitability, with varying yields and production timelines. The plant-made proteins revealed unexpected differences in N-glycan profiles, with BY2-RBD displaying oligo-mannosidic N-glycans and NB-RBD exhibiting a more complex glycan profile. This difference may be attributed to higher recombinant protein synthesis in the N. benthamiana system, potentially overloading the ER retention signal, causing some proteins to traffic to the Golgi apparatus. When used as diagnostic reagents in ELISA, BY2-RBD outperformed NB-RBD in terms of sensitivity, specificity, and correlation with a commercial kit. This discrepancy may be due to the distinct glycan profiles, as complex glycans on NB-RBD may impact immunoreactivity. In conclusion, our study highlights the potential of plant-based systems for rapid diagnostic reagent production during emergencies. However, transient expression systems, while offering shorter timelines, introduce higher heterogeneity in recombinant protein forms, necessitating careful consideration in serological test development.

show abstract

Section: Introductionmentioning

confidence: 99%

Performance of plant-produced RBDs as SARS-CoV-2 diagnostic reagents: a tale of two plant platforms

Santoni,

Gutierrez-Valdes,

Pivotto

et al. 2024

Front. Plant Sci.

View full text Add to dashboard Cite

show abstract

“…Using transient production in Nicotiana benthamiana a virus-like particle vaccine (Covifenz®) was produced by the company Medicago and approved by Health Canada as COVID-19 vaccine (Hager et al, 2022). Despite the fact that production of Covifenz® was not continued and Medicago ceased operations due to a management decision from its parent company (Benvenuto et al, 2023), the approval showed that this plant-made vaccine is safe and effective in preventing COVID-19. An RBD-based subunit vaccine that was effective, safe and non-toxic in animal studies is currently tested in phase 1 clinical trials (Phoolcharoen et al, 2023).…”

Section: Introductionmentioning

confidence: 99%

Impact of mutations on the plant-based production of recombinant SARS-CoV-2 RBDs

Ruocco,

Vavra,

König-Beihammer

et al. 2023

Front. Plant Sci.

View full text Add to dashboard Cite

Subunit vaccines based on recombinant viral antigens are valuable interventions to fight existing and evolving viruses and can be produced at large-scale in plant-based expression systems. The recombinant viral antigens are often derived from glycosylated envelope proteins of the virus and glycosylation plays an important role for the immunogenicity by shielding protein epitopes. The receptor-binding domain (RBD) of the SARS-CoV-2 spike is a principal target for vaccine development and has been produced in plants, but the yields of recombinant RBD variants were low and the role of the N-glycosylation in RBD from different SARS-CoV-2 variants of concern is less studied. Here, we investigated the expression and glycosylation of six different RBD variants transiently expressed in leaves of Nicotiana benthamiana. All of the purified RBD variants were functional in terms of receptor binding and displayed almost full N-glycan occupancy at both glycosylation sites with predominately complex N-glycans. Despite the high structural sequence conservation of the RBD variants, we detected a variation in yield which can be attributed to lower expression and differences in unintentional proteolytic processing of the C-terminal polyhistidine tag used for purification. Glycoengineering towards a human-type complex N-glycan profile with core α1,6-fucose, showed that the reactivity of the neutralizing antibody S309 differs depending on the N-glycan profile and the RBD variant.

show abstract