Covalent Functionalization of Melt-Blown Polypropylene Filters with Diazirine–Photosensitizer Conjugates Producing Visible Light Driven Virus Inactivating Materials.

The SARS-CoV-2 pandemic has highlighted the weaknesses of relying on single-use mask and respirator personal protective equipment (PPE) and the global supply chain that supports this market. There have been no major innovations in filter technology for PPE in the past two decades. Non-woven textiles used for filtering PPE are single-use products in the healthcare environment; use and protection is focused on preventing infection from airborne or aerosolized pathogens such as Influenza A virus SARS-CoV-2. Recently, C–H bond activation under mild and controllable conditions was reported for crosslinking commodity aliphatic polymers such as polyethylene and polypropylene. Significantly, these are the same types of polymers used in PPE filtration systems. In this report, we take advantage of this C–H insertion method to covalently attach a photosensitizing zinc-porphyrin to the surface of a melt-blow non-woven textile filter material. With the photosensitizer covalently attached to the surface of the textile, illumination with visible light was expected to produce oxidizing 1O2/ROS at the surface of the material that would result in pathogen inactivation. The filter was tested for its ability to inactivate Influenza A virus, an enveloped RNA virus similar to SARS-CoV-2, over a period of four hours with illumination of high intensity visible light. The photosensitizer-functionalized polypropylene filter inactivated our model virus by 99.99% in comparison to a control.

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Covalent functionalization of polypropylene filters with diazirine–photosensitizer conjugates producing visible light driven virus inactivating materials

Scientific Reports ◽

10.1038/s41598-021-98280-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

T. J. Cuthbert ◽

S. Ennis ◽

S. F. Musolino ◽

H. L. Buckley ◽

M. Niikura ◽

...

Keyword(s):

Visible Light ◽

Influenza A Virus ◽

Influenza A ◽

Bond Activation ◽

Rna Virus ◽

Filter Material ◽

Pathogen Inactivation ◽

Insertion Method ◽

Visible Light Driven ◽

Single Use

AbstractThe SARS-CoV-2 pandemic has highlighted the weaknesses of relying on single-use mask and respirator personal protective equipment (PPE) and the global supply chain that supports this market. There have been no major innovations in filter technology for PPE in the past two decades. Non-woven textiles used for filtering PPE are single-use products in the healthcare environment; use and protection is focused on preventing infection from airborne or aerosolized pathogens such as Influenza A virus or SARS-CoV-2. Recently, C–H bond activation under mild and controllable conditions was reported for crosslinking commodity aliphatic polymers such as polyethylene and polypropylene. Significantly, these are the same types of polymers used in PPE filtration systems. In this report, we take advantage of this C–H insertion method to covalently attach a photosensitizing zinc-porphyrin to the surface of a melt-blow non-woven textile filter material. With the photosensitizer covalently attached to the surface of the textile, illumination with visible light was expected to produce oxidizing 1O2/ROS at the surface of the material that would result in pathogen inactivation. The filter was tested for its ability to inactivate Influenza A virus, an enveloped RNA virus similar to SARS-CoV-2, over a period of four hours with illumination of high intensity visible light. The photosensitizer-functionalized polypropylene filter inactivated our model virus by 99.99% in comparison to a control.

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RNA Secondary Structure as a First Step for Rational Design of the Oligonucleotides towards Inhibition of Influenza A Virus Replication

Pathogens ◽

10.3390/pathogens9110925 ◽

2020 ◽

Vol 9 (11) ◽

pp. 925 ◽

Cited By ~ 1

Author(s):

Marta Szabat ◽

Dagny Lorent ◽

Tomasz Czapik ◽

Maria Tomaszewska ◽

Elzbieta Kierzek ◽

...

Keyword(s):

Secondary Structure ◽

Influenza A Virus ◽

Influenza A ◽

Rational Design ◽

Rna Virus ◽

Viral Rna ◽

Structure Information ◽

A Genome ◽

Function Relationship ◽

Interfering Rna

Influenza is an important research subject around the world because of its threat to humanity. Influenza A virus (IAV) causes seasonal epidemics and sporadic, but dangerous pandemics. A rapid antigen changes and recombination of the viral RNA genome contribute to the reduced effectiveness of vaccination and anti-influenza drugs. Hence, there is a necessity to develop new antiviral drugs and strategies to limit the influenza spread. IAV is a single-stranded negative sense RNA virus with a genome (viral RNA—vRNA) consisting of eight segments. Segments within influenza virion are assembled into viral ribonucleoprotein (vRNP) complexes that are independent transcription-replication units. Each step in the influenza life cycle is regulated by the RNA and is dependent on its interplay and dynamics. Therefore, viral RNA can be a proper target to design novel therapeutics. Here, we briefly described examples of anti-influenza strategies based on the antisense oligonucleotide (ASO), small interfering RNA (siRNA), microRNA (miRNA) and catalytic nucleic acids. In particular we focused on the vRNA structure-function relationship as well as presented the advantages of using secondary structure information in predicting therapeutic targets and the potential future of this field.

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Influenza A virus production in a single-use orbital shaken bioreactor with ATF or TFF perfusion systems

Vaccine ◽

10.1016/j.vaccine.2019.06.005 ◽

2019 ◽

Vol 37 (47) ◽

pp. 7011-7018 ◽

Cited By ~ 7

Author(s):

Juliana Coronel ◽

Ilona Behrendt ◽

Tim Bürgin ◽

Tibor Anderlei ◽

Volker Sandig ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Virus Production ◽

Single Use

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Production of high-titer human influenza A virus with adherent and suspension MDCK cells cultured in a single-use hollow fiber bioreactor

Vaccine ◽

10.1016/j.vaccine.2013.11.044 ◽

2014 ◽

Vol 32 (8) ◽

pp. 1003-1011 ◽

Cited By ~ 27

Author(s):

Felipe Tapia ◽

Thomas Vogel ◽

Yvonne Genzel ◽

Ilona Behrendt ◽

Mark Hirschel ◽

...

Keyword(s):

Influenza A Virus ◽

Hollow Fiber ◽

Influenza A ◽

Mdck Cells ◽

High Titer ◽

Human Influenza ◽

Hollow Fiber Bioreactor ◽

Single Use ◽

Cells Cultured

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A Non-phylogeny-dependent Reassortment Detection Method for Influenza A Viruses

Frontiers in Virology ◽

10.3389/fviro.2021.751196 ◽

2021 ◽

Vol 1 ◽

Author(s):

Xingfei Gong ◽

Mingda Hu ◽

Boqian Wang ◽

Haoyi Yang ◽

Yuan Jin ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Detection Method ◽

Rna Virus ◽

Self Organizing Map ◽

Influenza A Viruses ◽

Multiple Sequence ◽

Distance Methods ◽

Virus Reassortment ◽

Pandemic Strains

Influenza A virus is a segmented RNA virus whose genome consists of 8 single-stranded negative-sense RNA segments. This unique genetic structure allows viruses to exchange their segments through reassortment when they infect the same host cell. Studying the determination and nature of influenza A virus reassortment is critical to understanding the generation of pandemic strains and the spread of viruses across species. Reassortment detection is the first step in influenza A virus reassortment research. Several methods for automatic detection of reassortment have been proposed, which can be roughly divided into two categories: phylogenetic methods and distance methods. In this article, we proposed a reassortment detection method that does not require multiple sequence alignment and phylogenetic analysis. We extracted the codon features from the segment sequence and expressed the sequence as a feature vector, and then used the clustering method of self-organizing map to cluster the sequence for each segment. Based on the clustering results and the epidemiological information of the virus, the reassortment detection was implemented. We used this method to perform reassortment detection on the collected 7,075 strains from Asia and identified 516 reassortment events. We also conducted a statistical analysis of the identified reassortment events and found conclusions consistent with previous studies. Our method will provide new insights for automating reassortment detection tasks and understanding the reassortment patterns of influenza A viruses.

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Single cell infection with influenza A virus using drop-based microfluidics

10.1101/2021.09.14.460333 ◽

2021 ◽

Author(s):

Emma Kate Loveday ◽

Humberto S. Sanchez ◽

Mallory M. Thomas ◽

Connie B. Chang

Keyword(s):

Single Cell ◽

Influenza A Virus ◽

Influenza A ◽

Single Cell Analysis ◽

Rna Virus ◽

Host Cells ◽

Single Cell Level ◽

Cell Infection ◽

Cell Level ◽

High Genetic Diversity

SummaryInfluenza A virus (IAV) is an RNA virus with high genetic diversity which necessitates the development of new vaccines targeting emerging mutations each year. As IAV exists in genetically heterogeneous populations, current studies focus on understanding population dynamics at the single cell level. These studies include novel methodology that can be used for probing populations at the single cell level, such as single cell sequencing and microfluidics. Here, we introduce a drop-based microfluidics method to study IAV infection at a single cell level by isolating infected host cells in microscale drops. Single human alveolar basal epithelial (A549), Madin-Darby Canine Kidney cells (MDCK) and MDCK + human siat7e gene (Siat7e) cells infected with the pandemic A/California/07/2009 (H1N1) strain were encapsulated within 50 μm radii drops and incubated at 37°C. We demonstrate that drops remain stable over 24 hours, that 75% of cells remain viable, and that IAV virus can propagate within the drops. Drop-based microfluidics therefore enables single cell analysis of viral populations produced from individually infected cells.

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Roles of the Non-Structural Proteins of Influenza A Virus

Pathogens ◽

10.3390/pathogens9100812 ◽

2020 ◽

Vol 9 (10) ◽

pp. 812

Author(s):

Wenzhuo Hao ◽

Lingyan Wang ◽

Shitao Li

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Rna Virus ◽

Critical Role ◽

Viral Proteins ◽

Host Cells ◽

Structural Proteins ◽

Host Interactions ◽

New Findings ◽

Seasonal Epidemics

Influenza A virus (IAV) is a segmented, negative single-stranded RNA virus that causes seasonal epidemics and has a potential for pandemics. Several viral proteins are not packed in the IAV viral particle and only expressed in the infected host cells. These proteins are named non-structural proteins (NSPs), including NS1, PB1-F2 and PA-X. They play a versatile role in the viral life cycle by modulating viral replication and transcription. More importantly, they also play a critical role in the evasion of the surveillance of host defense and viral pathogenicity by inducing apoptosis, perturbing innate immunity, and exacerbating inflammation. Here, we review the recent advances of these NSPs and how the new findings deepen our understanding of IAV–host interactions and viral pathogenesis.

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Zinc-embedded fabrics inactivate SARS-CoV-2 and influenza A virus

10.1101/2020.11.02.365833 ◽

2020 ◽

Author(s):

Vikram Gopal ◽

Benjamin E. Nilsson-Payant ◽

Hollie French ◽

Jurre Y. Siegers ◽

Wai-shing Yung ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Rna Virus ◽

Zinc Content ◽

Respiratory Viruses ◽

Zinc Ions ◽

Liquid Droplets ◽

Influenza A Viruses ◽

Wide Range ◽

Polyamide 6.6

AbstractInfections with respiratory viruses can spread via liquid droplets and aerosols, and cause diseases such as influenza and COVID-19. Face masks and other personal protective equipment (PPE) can act as barriers that prevent the spread of respiratory droplets containing these viruses. However, influenza A viruses and coronaviruses are stable for hours on various materials, which makes frequent and correct disposal of these PPE important. Metal ions embedded into PPE may inactivate respiratory viruses, but confounding factors such as absorption of viruses make measuring and optimizing the inactivation characteristics difficult. Here we used polyamide 6.6 (PA66) fibers that had zinc ions embedded during the polymerisation process and systematically investigated if these fibers can absorb and inactivate pandemic SARS-CoV-2 and influenza A virus H1N1. We find that these viruses are readily absorbed by PA66 fabrics and inactivated by zinc ions embedded into this fabric. The inactivation rate (pfu·gram−1·min−1) exceeds the number of active virus particles expelled by a cough and supports a wide range of viral loads. Moreover, we found that the zinc content and the virus inactivating property of the fabric remain stable over 50 standardized washes. Overall, these results provide new insight into the development of “pathogen-free” PPE and better protection against RNA virus spread.

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The virucidal effects of 405 nm visible light on SARS-CoV-2 and influenza A virus

Scientific Reports ◽

10.1038/s41598-021-97797-0 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Raveen Rathnasinghe ◽

Sonia Jangra ◽

Lisa Miorin ◽

Michael Schotsaert ◽

Clifford Yahnke ◽

...

Keyword(s):

Visible Light ◽

Influenza A Virus ◽

Influenza A ◽

Ultra Violet ◽

Electromagnetic Spectrum ◽

Respiratory Pathogens ◽

Cellular Functions ◽

Free Radical Damage ◽

Irradiation Energy ◽

Potential Alternative

AbstractThe germicidal potential of specific wavelengths within the electromagnetic spectrum is an area of growing interest. While ultra-violet (UV) based technologies have shown satisfactory virucidal potential, the photo-toxicity in humans coupled with UV associated polymer degradation limit their use in occupied spaces. Alternatively, longer wavelengths with less irradiation energy such as visible light (405 nm) have largely been explored in the context of bactericidal and fungicidal applications. Such studies indicated that 405 nm mediated inactivation is caused by the absorbance of porphyrins within the organism creating reactive oxygen species which result in free radical damage to its DNA and disruption of cellular functions. The virucidal potential of visible-light based technologies has been largely unexplored and speculated to be ineffective given the lack of porphyrins in viruses. The current study demonstrated increased susceptibility of lipid-enveloped respiratory pathogens of importance such as SARS-CoV-2 (causative agent of COVID-19) and influenza A virus to 405 nm, visible light in the absence of exogenous photosensitizers thereby indicating a potential alternative porphyrin-independent mechanism of visible light mediated viral inactivation. These results were obtained using less than expected irradiance levels which are considered safe for humans and commercially achievable. Our results support further exploration of the use of visible light technology for the application of continuous decontamination in occupied areas within hospitals and/or infectious disease laboratories, specifically for the inactivation of respiratory pathogens such as SARS-CoV-2 and Influenza A.

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Covalent Functionalization of Melt-Blown Polypropylene Filters with Diazirine–Photosensitizer Conjugates Producing Visible Light Driven Virus Inactivating Materials.