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1.
Biochem J ; 2022 Apr 05.
Article in English | MEDLINE | ID: covidwho-1774010

ABSTRACT

Diagnostic testing continues to be an integral component of the strategy to contain the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) global pandemic, the causative agent of Coronavirus Disease 2019 (COVID-19).  The SARS-CoV-2 genome encodes the 3C-like protease (3CLpro) which is essential for coronavirus replication.  This study adapts an in vitro colorimetric gold nanoparticle (AuNP) based protease assay to specifically detect the activity of SARS-CoV-2 3CLpro as a purified recombinant protein and as a cellular protein exogenously expressed in HEK293T human cells.  We also demonstrate that the specific sensitivity of the assay for SARS-CoV-2 3CLpro can be improved by use of an optimised peptide substrate and through hybrid dimerisation with inactive 3CLpro mutant monomers.  These findings highlight the potential for further development of the AuNP protease assay to detect SARS-CoV-2 3CLpro activity as a novel, accessible and cost-effective diagnostic test for SARS-CoV-2 infection at the point-of-care.  Importantly, this versatile assay could also be easily adapted to detect specific protease activity associated with other viruses or diseases conditions.

2.
PLoS Pathog ; 18(2): e1010265, 2022 02.
Article in English | MEDLINE | ID: covidwho-1686115

ABSTRACT

Efforts to define serological correlates of protection against COVID-19 have been hampered by the lack of a simple, scalable, standardised assay for SARS-CoV-2 infection and antibody neutralisation. Plaque assays remain the gold standard, but are impractical for high-throughput screening. In this study, we show that expression of viral proteases may be used to quantitate infected cells. Our assays exploit the cleavage of specific oligopeptide linkers, leading to the activation of cell-based optical biosensors. First, we characterise these biosensors using recombinant SARS-CoV-2 proteases. Next, we confirm their ability to detect viral protease expression during replication of authentic virus. Finally, we generate reporter cells stably expressing an optimised luciferase-based biosensor, enabling viral infection to be measured within 24 h in a 96- or 384-well plate format, including variants of concern. We have therefore developed a luminescent SARS-CoV-2 reporter cell line, and demonstrated its utility for the relative quantitation of infectious virus and titration of neutralising antibodies.


Subject(s)
Biosensing Techniques/methods , COVID-19 Testing/methods , COVID-19/virology , Luminescent Measurements/methods , Peptide Hydrolases/analysis , SARS-CoV-2/enzymology , Viral Proteins/analysis , COVID-19/diagnosis , Cell Line , Humans , Peptide Hydrolases/genetics , Peptide Hydrolases/metabolism , SARS-CoV-2/genetics , SARS-CoV-2/physiology , Viral Proteins/genetics , Viral Proteins/metabolism , Virus Replication
3.
J Cyst Fibros ; 20 Suppl 3: 49-54, 2021 12.
Article in English | MEDLINE | ID: covidwho-1587337

ABSTRACT

BACKGROUND: Due to the COVID-19 pandemic, there was an uptake of telehealth in cystic fibrosis care. Previous studies show disparities in telehealth use based on socioeconomic status (SES). We aimed to: (1) understand telehealth use and perceptions and (2) identify the facilitators and barriers to telehealth use among people with CF and their families (PwCF) from diverse racial/ethnic and socioeconomic backgrounds. METHODS: We conducted an analysis of the 2020 Cystic Fibrosis State of Care surveys completed by PwCF (PFSoC), CF Care Programs (SoC1) and the CF Foundation Patient Registry (CFFPR). RESULTS: A total of 424 PwCF and 286 programs responded to the PFSoC and SoC1. Among PwCF, 90% self-identified as White, 6% as Hispanic/Latino, and 2% as Black. Racial/ethnic minorities were less likely to have had a telehealth visit (p=.015). This difference was pronounced among the Hispanic/Latino population (p<.01). Telehealth use did not differ by health insurance and was similarly offered independent of financial status. Compared to PwCF who denied financial constraints, those who reported financial difficulties found telehealth more difficult to use (p=.018) and were less likely to think that their concerns (p=.010) or issues that mattered most to them (p=.020) were addressed during telehealth. Programs perceived lack of technology, language barriers, and home conditions as barriers to telehealth in vulnerable populations. CONCLUSION: PFSoC and SoC1 identified differences in telehealth use and care perceptions by ethnicity, race, and socioeconomic characteristics. Further studies are needed to understand how telehealth can change access to CF care in diverse subpopulations.


Subject(s)
COVID-19 , Communication Barriers , Cystic Fibrosis , Minority Health , Telemedicine , COVID-19/epidemiology , COVID-19/prevention & control , Communicable Disease Control/methods , Cystic Fibrosis/economics , Cystic Fibrosis/ethnology , Cystic Fibrosis/psychology , Cystic Fibrosis/therapy , Financial Stress/ethnology , Health Services Accessibility/organization & administration , Health Services Accessibility/trends , Healthcare Disparities/ethnology , Healthcare Disparities/standards , Humans , Minority Health/ethnology , Minority Health/standards , Minority Health/statistics & numerical data , Needs Assessment , Organizational Innovation , SARS-CoV-2 , Socioeconomic Factors , Telemedicine/organization & administration , Telemedicine/standards , United States/epidemiology , Vulnerable Populations/statistics & numerical data
4.
J Cyst Fibros ; 20 Suppl 3: 16-20, 2021 12.
Article in English | MEDLINE | ID: covidwho-1587336

ABSTRACT

BACKGROUND: Chronic care delivery models faced unprecedented financial pressures, with a reduction of in-person visits and adoption of telehealth during the COVID-19 pandemic. We sought to understand the reported financial impact of pandemic-related changes to the cystic fibrosis (CF) care model. METHODS: The U.S. CF Foundation State of Care surveys fielded in Summer 2020 (SoC1) and Spring 2021 (SoC2) included questions for CF programs on the impact of pandemic-related restrictions on overall finances, staffing, licensure, and reimbursement of telehealth services. Descriptive analyses were conducted based on program type. RESULTS: Among the 286 respondents (128 pediatric, 118 adult, 40 affiliate), the majority (62%) reported a detrimental financial impact to their CF care program in SoC1, though fewer (42%) reported detrimental impacts in SoC2. The most common reported impacts in SoC1 were redeployment of clinical staff (68%), furloughs (52%), hiring freezes (51%), decreases in salaries (34%), or layoffs (10%). Reports of lower reimbursement for telehealth increased from 30% to 40% from SoC1 to SoC2. Projecting towards the future, only a minority (17%) of program directors in SoC2 felt that financial support would remain below pre-pandemic levels. CONCLUSIONS: The COVID-19 pandemic resulted in financial strain on the CF care model, including challenges with reimbursement for telehealth services and reductions in staffing due to institutional changes. Planning for the future of CF care model needs to address these short-term impacts, particularly to ensure a lack of interruption in high-quality multi-disciplinary care.


Subject(s)
COVID-19 , Continuity of Patient Care , Cystic Fibrosis , Health Services Accessibility , Models, Organizational , Telemedicine , Adult , COVID-19/epidemiology , COVID-19/prevention & control , Child , Continuity of Patient Care/organization & administration , Continuity of Patient Care/standards , Costs and Cost Analysis , Cystic Fibrosis/economics , Cystic Fibrosis/epidemiology , Cystic Fibrosis/therapy , Health Services Accessibility/organization & administration , Health Services Accessibility/trends , Health Services Needs and Demand , Humans , Organizational Innovation , Personnel Staffing and Scheduling/organization & administration , Reimbursement Mechanisms/trends , SARS-CoV-2 , Telemedicine/economics , Telemedicine/methods , United States/epidemiology
5.
J Cyst Fibros ; 20 Suppl 3: 3-8, 2021 12.
Article in English | MEDLINE | ID: covidwho-1587345

ABSTRACT

BACKGROUND: Novel therapies have dramatically changed cystic fibrosis (CF) and innovative care delivery systems are needed to meet future patient needs. Telehealth has been shown to be an efficient and desirable form of care delivery. The COVID-19 pandemic caused a rapid shift to telehealth, and this presented a unique opportunity to study facilitators, barriers, and satisfaction with this mode of care delivery. We aim to report survey methods, demographics and telehealth use among CF care programs, patients, and families during the pandemic. METHODS: CF programs completed two surveys between July 29 and September 18, 2020, and between April 19 and May 19, 2021. Patients and families completed a similar survey between August 31 and October 30, 2020. The surveys addressed topics assessing the pandemic's financial impact, telehealth modes and experiences, licensure and reimbursement issues, health screening, and remote monitoring. Quantitative data were analyzed with descriptive statistics and were compared to the CF Foundation Patient Registry. RESULTS: Most programs (278 at timepoint one and 274 at timepoint two) provided telehealth during the pandemic. The percent of visits containing either telephone or video components changed from 45% to 25% over the time periods. Additionally, 424 patients and families from various ages and backgrounds responded to the survey and 81% reported having a telehealth visit. CONCLUSIONS: The pandemic accelerated telehealth adoption and these datasets are a valuable source for exploring telehealth barriers and facilitators, the quality-of-care experience, financial and workforce implications, the impact on underrepresented populations, and implications for coverage and reimbursement.


Subject(s)
COVID-19 , Cystic Fibrosis , Health Services Accessibility , Telemedicine , Adult , COVID-19/epidemiology , COVID-19/prevention & control , Child , Communicable Disease Control/methods , Communication Barriers , Continuity of Patient Care , Costs and Cost Analysis , Cystic Fibrosis/epidemiology , Cystic Fibrosis/psychology , Cystic Fibrosis/therapy , Female , Health Services Accessibility/organization & administration , Health Services Accessibility/trends , Humans , Male , Organizational Innovation , Patient Satisfaction/statistics & numerical data , Quality of Health Care , SARS-CoV-2 , Telemedicine/organization & administration , Telemedicine/standards , United States/epidemiology
6.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-294784

ABSTRACT

Efforts to define serological correlates of protection against COVID-19 have been hampered by the lack of a simple, scalable, standardised assay for SARS-CoV-2 infection and antibody neutralisation. Plaque assays remain the gold standard, but are impractical for high-throughput screening. In this study, we show that expression of viral proteases may be used to quantitate infected cells. Our assays exploit the cleavage of specific oligopeptide linkers, leading to the activation of cell-based optical biosensors. First, we characterise these biosensors using recombinant SARS-CoV-2 proteases. Next, we confirm their ability to detect viral protease expression during replication of authentic virus. Finally, we generate reporter cells stably expressing an optimised luciferase-based biosensor, enabling viral infection to be measured within 24 h in a 96- or 384-well plate format, including variants of concern. We have therefore developed a luminescent SARS-CoV-2 reporter cell line, and demonstrated its utility for the relative quantitation of infectious virus and titration of neutralising antibodies. Author summary Techniques for measuring infection with SARS-CoV-2 in the laboratory are laborious and time-consuming, and different laboratories use different approaches. There is therefore no generally agreed way to quantitate neutralising antibodies against SARS-CoV-2, which block infection with the virus and protect people from COVID-19. In this study, we describe a new way to measure SARS-CoV-2 infection, which is much simpler and faster than existing methods. It relies on the production of a specific protease enzyme by the virus, which is able to cleave and activate an engineered protein biosensor in infected cells. This biosensor emits light in the presence of viral infection, and the amount of light released is used as a readout for the amount of infectious SARS-CoV-2 present. The signal is very sensitive, so the number of infected cells required is very small, and the method can be scaled-up to test many samples at once. In particular, we demonstrate how it can be used to detect different variants of SARS-CoV-2, and quantitate neutralising antibodies against these viruses.

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