Biology subjects

Khaiboullina, S.

Publications and source records attributed to Khaiboullina, S..

3 recordsLinked to original sources

bioRxiv2022

Screening of SARS-CoV-2 Antivirals Through a Cell-Based RNA-Dependent RNA Polymerase (RdRp) Reporter Assay

COVID-19 (Coronavirus Disease 2019) caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus-2) continues to pose international public health threat and thus far, has resulted in greater than 5.6 million deaths worldwide. Vaccines are critical tools to limit COVID-19 spread, but antiviral drug development is an ongoing global priority due to fast spreading COVID-19 variants that may elude vaccines efficacies. The RNA-dependent RNA polymerase (RdRp) of SARS-CoV-2 is an essential enzyme of viral replication and transcription machinery complex. Therefore, the RdRp is an attractive target for the development of effective anti-COVID-19 therapeutics. In this study, we developed a cell-based assay to determine the enzymatic activity of SARS-CoV-2 RdRp through luciferase reporter system. The SARS-CoV-2 RdRp reporter assay was validated using a known inhibitors of RdRp polymerase, remdesivir along with other anti-virals including ribavirin, penciclovir, rhoifolin, 5CT, and dasabuvir. Among these inhibitors, dasabuvir (FDA-approved drug) exhibited promising RdRp inhibitory activity. Anti-viral activity of dasabuvir was also tested on the replication of SARS-CoV-2 through infection of Vero E6 cells. Dasabuvir inhibited the replication of SARS-CoV-2, USA-WA1/2020 as well as B.1.617.2 (delta variant) in Vero E6 cells in a dose-dependent manner with IC50 values 9.47 M and 10.48 M, for USA-WA1/2020 and B.1.617.2 variants, respectively). Our results suggests that dasabuvir can be further evaluated as a therapeutic drug for COVID-19. In addition, our assays provide robust, target-specific, and high-throughput screening compatible (z- and z-factors of > 0.5) platforms that will be a valuable tool for the screening SARS-CoV-2 RdRp inhibitors. SignificanceSARS-CoV-2 has caused a major public crisis world has seen in recent history. Development of vaccines and emergency use authorization of anti-virals are helping in reducing the burden of SARS-CoV-2 caused hospitalization and deaths. However, there is still need for optimal anti-viral(s) that can efficiently block viral propagation, and targeting viral polymerase (RdRp) is an among the most suitable targets for clamping viral replication. In this study, we developed a cell-based assay to screen potential compounds capable of blocking RdRp activity. The efficacy of our assay was validated by using already approved anti-virals, which reduced RdRp activity and slowed the replication of two SARS-CoV-2 variants (WA1 USA-WA1/2020 and B.1.617.2) in a cell culture model. This confirmed that our system can be used for identifying potential anti-SARS-CoV-2 anti-virals.

microbiology↗

bioRxiv2020

In Vitro Inactivation of Human Coronavirus by Titania Nanoparticle Coatings and UVC Radiation: Throwing Light on SARS-CoV-2

The newly identified pathogenic human coronavirus, SARS-CoV-2, led to an atypical pneumonia-like severe acute respiratory syndrome (SARS) outbreak called coronavirus disease 2019 (COVID-19). Currently, nearly 23 million cases have been confirmed worldwide with the highest COVID-19 cases been confirmed in the United States. As there is no vaccine or any effective interventions, massive efforts to create a postential vaccine to combat COVID-19 is underway. In the meantime, safety precautions and effective disease control strategies appear to be vital for preventing the virus spread in the public places. Due to the longevity of the virus on smooth surfaces, photocatalytic properties of self-disinfecting/cleaning surfaces appear to be a promising tool to help guide disinfection policies to control infectious SAR-CoV-2 spread in high-traffic areas such as hospitals, grocery stores, airports, schools, and stadiums. Here, we explored the photocatalytic properties of nanosized TiO2 (TNPs) as induced by the UV radiation, towards virus deactivation. Our preliminary results using close genetic relative of SAR-CoV-2, HCoV-NL63, showed the virucidal efficacy of photoactive TNPs deposited on glass coverslips, as examined by quantitative RT-PCR and virus culture assays. Efforts to extrapolate the underlying concepts described in this study to SARS-CoV-2 are currently underway.

microbiology↗

bioRxiv2019

Angiogenic activity of cytochalasin B-induced membrane vesicles of human mesenchymal stem cells

BackgroundThe cytochalasin B-induced membrane vesicles (CIMVs) are suggested to be used as a vehicle for the delivery of therapeutics. However, the angiogenic activity and therapeutic potential of human mesenchymal stem cells (MSCs) derived CIMVs (CIMVs-MSCs) remains unknown.\n\nObjectivesThe objectives of this study were to analyzed the morphology, size distribution, molecular composition and angiogenic properties of CIMVs-MSCs.\n\nMethodsThe morphology of CIMVs-MSC was analyzed by scanning electron microscopy. The proteomic analysis, multiplex analysis and immunostaining were used to characterize the molecular composition of the CIMVs-MSCs. The transfer of surface proteins from a donor to a recipient cell mediated by CIMVs-MSCs was demonstrated using immunostaining and confocal microscopy. The angiogenic potential of CIMVs-MSCs was evaluated using in vivo approach of subcutaneous implantation of CIMVs-MSCs in mixture with Matrigel matrix.\n\nResultsHuman CIMVs-MSCs retain parental MSCs content such as growth factors, cytokines, chemokines: EGF, FGF-2, Eotaxin, TGF-, G-CSF, Flt-3L, GM-CSF, Fractalkine, IFN2, IFN-{gamma}, GRO, IL-10, MCP-3, IL-12p40, MDC, IL-12p70, IL-15, sCD40L, IL-17A, IL-1RA, IL-1a, IL-9, IL-1b, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IP-10, MCP-1, MIP_1a, MIP-1b, TNF-, TNF-{beta}, VEGF. CIMVs-MSCs also have the expression of surface receptors similar to those in parental human MSCs (CD90+, CD29+, CD44+, CD73+). Additionally, CIMVs-MSCs could transfer membrane receptors to the surfaces of target cells in vitro. Finally, CIMVs-MSCs can induce angiogenesis in vivo after subcutaneous injection into adult rats.\n\nConclusionsHuman CIMVs-MSCs have similar content, immunophenotype and angiogenic activity to those of the parental MSCs. Therefore, we believe that human CIMVs-MSCs could be used for cell free therapy of degenerative diseases.

cell biology↗