Technologies
Virongy Biosciences develops cutting-edge technologies in virology and viral vectors to accelerate scientific discovery, clinical diagnostics, and disease treatment.
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Alphavirus-based pseudoviruses are a newly developed proprietary pseudovirus platform for rapidly screening viral entry inhibitors and neutralizing antibodies. Alpha pseudoviruses consist of a virus-like particle (VLP) that encapsulates an alphavirus-derived RNA genome for rapid report expression (luciferase or GFP) in target cells (Hetrick et al., 2022). This represents a major technological advancement in the development of pseudoviruses for BSL-3 and BSL-4 level viral pathogens, allowing common biolabs to conduct rapid and robust antiviral drug screening and antibody neutralization assays. Currently, Virongy has developed a series of alpha pseudoviruses for the following viruses:
- SARS-CoV-2 and SARS-CoV: Ha-CoV-2 and Ha-CoV represents a major technology advancement in the development of SARS-CoV-2 pseudoviruses, and serves as platforms for rapid and robust quantification of neutralizing antibodies, viral mutants, and antiviral drugs (Dabbagh et al., 2021; He et al., 2021). Different from commonly used S protein pseudotyped lenti- or vesicular stomatitis virus (VSV)-psedoviruses, Ha-CoV-2 is assembled with all 4 structural proteins (S, M, N, and E) of SARS-CoV-2, and contains a reporter genome derived from an alphavirus-based vector for rapid (6 hours) and robust expression of reporter genes. Neutralization assays conducted with Ha-CoV-2 and the infectious SARS-CoV-2 showed a direct correlation (R2 = 0.87) validating that Ha-CoV-2 can serve as a surrogate of SARS-CoV-2 for neutralizing antibody quantification. SARS-CoV-2 and SARS-CoV cause respiratory coronavirus diseases and are BSL-3-level pathogens.
- Nipah Virus: Ha-NiV is derived from Nipah virus (NiV), an enveloped paramyxovirus with negative-sense and a non-segmented RNA genome. Henipaviruses are zoonotic viruses causing encephalitis and are BSL-4-level pathogens. The Ha-NiV particles consist of the four major structural proteins of the Henipavirus, the attachment glycoprotein (G), the fusion protein (F), the matrix protein (M) and the nucleocapsid protein (N). The NiV VLP encapsulates and alphavirus genome to rapidly express a reporter gene or gene of interest.
- Ebola/Marburg: Ha-EboV are derived from the Zaire Ebolavirus and Marburgvirus, members of Filoviridae with single-stranded negative-sense RNA genome. Ebola/Marburg causes. Ebolaviruses causes Ebola hemorrhagic fever and is a BSL-4-level pathogen. The Ha-EBOVV/Ha-MARV particles consist of the viral glycoprotein (GP), nucleoprotein (NP) and the VP40 matrix protein. The EBOV/MARV VLP encapsulates and alphavirus genome to rapidly express a reporter gene or gene of interest.
- Lassa mammarenavirus: Ha-LasV is derived from Lassa mammarenavirus (LASV), an arenavirus with single-stranded, bisegmented, ambisense-sense RNA genome. Lassa virus causes Lassa hemorrhagic fever and is a BSL-4-level pathogen. The Ha-LASV particle consist of the glycoprotein (GP) and the matrix protein (Z). The LASV VLP encapsulates and alphavirus genome to rapidly express a reporter gene or gene of interest.
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Infectin is a proprietary technology developed at Virongy and based on the scientific theory that cortical actin is a natural barrier for viral entry and intracellular migration towards the cytosol and the nucleus (Yoder et al., 2008). Cortical actin is a dense meshwork of actin filaments (F-actin) underneath the plasma membrane. It provides mechanical support to cells and is a major driving force for cell motility.
Cortical actin represents a structural impediment for viral intracellular migration towards sites where viruses replicate and assemble. Viruses devise strategies to exploit various cellular regulatory mechanisms of actin dynamics in order to overcome the cortical actin barrier. Many viruses use endocytosis to penetrate the cortical actin meshwork. The endosomal entry of viruses also requires active actin polymerization to drive endosome scission from the plasma membrane.
Infectin is designed to increase actin dynamics to facilitate viral penetration of the cortical actin barrier, thereby greatly facilitating productive viral infection. Infectin can enhance the numbers of productively infected cells by 3- to 30-fold. It can be used to drastically increase the viral infection rate to facilitate biochemical characterization of viral infection.
Infectin can be used as a routine viral infection-enhancing reagent to increase productive viral vector transduction rates, particularly for common vectors such as lenti- and retroviral vectors
The HIV Rev-dependent reporter cells licensed and commercialized by Virongy represent a major advancement in the development of HIV indicator cells (Wu et al., 2007). This new reporter system differs dramatically from the common LTR-based reporter cells, which rely solely on the HIV promoter, the long terminal repeat (LTR), to drive reporter expression.
The HIV Rev-dependent reporter platform are the best HIV-indicators on the market, with the highest specificity and accuracy in quantifying HIV infection. They can be used for anti-HIV drug screening, anti-HIV antibody screening, and the screening of anti-HIV compounds targeting host restriction or dependency factors (Wu et al., 2007, Curr HIV Res. 5:394).
SARS-CoV-2 Reporter cells were infected with either mock virus or authentic SARS-CoV-2. The reporter was quantified by fluorescent microscopy two days post-infection.
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The SARS-CoV-2 reporter cell is a proprietary technology developed at Virongy. This first-of-its kind reporter cell represents a major advancement in the development of rapid coronavirus indicators cells. Our reporter cells carry a stably integrated reporter construct that is derived from a mini-antisense genome of SARS-CoV-2.
Authentic SARS-CoV-2 replicase proteins permit reporter expression by converting the mini-antisense genome into a positive-sense genome. The cell line is derived from Virongy’s HEK293T(ACE2/TMPRSS2) cells which express high levels of ACE2 and TMPRSS2 to permit SARS-CoV-2 entry. The SARS-CoV-2 GFP reporter cells turn GFP positive upon live virus infection. The SARS-CoV-2 reporter cell line does not produce any viral proteins and does not greatly impact overall viral replication.Key Features:
- High Sensitivity and Specificity – Minimal Background Signal
- Rapid quantification of SARS-CoV-2 infectious titer in less than 24 hours.
- No need for performing plaque assays and counting plaques
- GFP reporter for rapid and easy enumeration of infected cells with a flow cytometer or fluorescent microscope
- With enhanced accuracy – results are not affected by inaccurate plaque counting and loss of cells during cell fixing and staining.
The Exo-HEK293T enhances the production of exosomes and microvesicles, providing customers with consistent production of quality EVs that can be customized to meet individual research needs. Combine with our high-efficiency transfection reagent, Transfectin, for simple and rapid production of exosomes and EVs.
Key Features:
- High exosome and microvesicle production rate
- Customizable to fit your research needs
- Consistent production for long-term use
ExoMaxed Expression of CD9
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