Technologies
Virongy Biosciences develops cutting-edge technologies in virology and viral vectors to accelerate scientific discovery, clinical diagnostics, and disease treatment.
Virongy's Key Technologies
- 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 5- to 20-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.
Hybrid alpha-pseudoviruses are a newly developed pseudovirus platform for rapidly screening viral entry inhibitors. They 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). Ha-CoV-2 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
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.
- While responsive to an early HIV protein, Tat, the LTR is also responsive to cell culture conditions and stimulation by a variety of known and unknown factors, including cytokines, mitogens, HDAC inhibitors, lipopolysaccharide, certain anti-tumor drugs, and free viral proteins (Siekevitz et al., 1987; Sweet et al., 1995).
- In contrast to the LTR-based reporter cells, our Rev-dependent reporter cells use both LTR and the Rev/RRE interaction to regulate reporter gene expression. This strict requirement for Rev, a viral protein present only in infected cells, drastically improves the reporter specificity and sensitivity.
- This unparalleled sensitivity and specificity means that our Rev-dependent reporter cells are suitable for a broad range of applications, including screening broadly neutralizing antibodies and anti-HIV drugs, and studying HIV cell-cell transmission and host restriction and dependency factors.
- Derived from CD4 T-cells, our reporter cells express native levels of HIV receptors, and are natural HIV targets with broad susceptibility to X4, R5, primary HIV isolates, and certain SIV strains.
- With GFP, Luc, or GFP/Luc detection options, our Rev-dependent cells provide a versatile and flexible platform for HIV research.
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