Baculovirus-Free SARS-CoV-2 Virus-like Particle Production in Insect Cells for Rapid Neutralization Assessment.
Marcel JaronMichael LehkyMarta ZaràChris Nicole ZaydowiczAidin LakRico BallmannPhilip Alexander HeineEsther Veronika WenzelKai-Thomas SchneiderFederico BertoglioSusanne KempterReinhard Wolfgang KösterSilvia Stella BarbieriJoop van den HeuvelMichael HustStefan DübelMaren SchubertPublished in: Viruses (2022)
Virus-like particles (VLPs) resemble authentic virus while not containing any genomic information. Here, we present a fast and powerful method for the production of SARS-CoV-2 VLP in insect cells and the application of these VLPs to evaluate the inhibition capacity of monoclonal antibodies and sera of vaccinated donors. Our method avoids the baculovirus-based approaches commonly used in insect cells by employing direct plasmid transfection to co-express SARS-CoV-2 envelope, membrane, and spike protein that self-assemble into VLPs. After optimization of the expression plasmids and vector ratios, VLPs with an ~145 nm diameter and the typical "Corona" aura were obtained, as confirmed by nanoparticle tracking analysis (NTA) and transmission electron microscopy (TEM). Fusion of the membrane protein to GFP allowed direct quantification of binding inhibition to angiotensin II-converting enzyme 2 (ACE2) on cells by therapeutic antibody candidates or sera from vaccinated individuals. Neither VLP purification nor fluorescent labeling by secondary antibodies are required to perform these flow cytometric assays.
Keyphrases
- sars cov
- induced apoptosis
- angiotensin ii
- cell cycle arrest
- escherichia coli
- oxidative stress
- endoplasmic reticulum stress
- poor prognosis
- cell death
- vascular smooth muscle cells
- dna methylation
- binding protein
- crispr cas
- healthcare
- signaling pathway
- small molecule
- long non coding rna
- social media
- copy number
- high throughput
- transcription factor
- klebsiella pneumoniae
- genome wide
- optic nerve
- single cell
- health information
- amino acid