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Developmental Biology COVID-19

Scientists Identify COVID-19 Vaccine Targets

Scientists identify a set of potential vaccine targets for SARS-CoV-2 coronavirus...

The beginning of 2020 saw the SARS-CoV-2 outbreak in mainland China, which quickly spread to over 30 countries around the world, infecting over 80,000 people, and causing over 2,600 deaths as of late February 2020.

Now a team of scientists at the Hong Kong University of Science and Technology (HKUST) has identified a set of potential vaccine targets for the SARS-CoV-2 coronavirus. These targets are crucial for guiding efforts against COVID-19 pneumonia and towards development of a vaccine.
Like SARS-CoV, which caused the SARS (Severe Acute Respiratory Syndrome) outbreak in 2003, SARS-CoV-2 belongs to the same genus as Betacoronavirus.

By considering the genetic similarity between SARS-CoV-2 and SARS-CoV, scientists leveraged immunological data to identify a set of SARS-CoV- derived B cell and T cell Epitopes that exactly match SARS-CoV-2, and act as biomarkers recognized only by our immune system which triggers an immune response against the virus.
As no mutation was observed in epitopes among the available SARS-CoV-2 genetic sequences, immune targeting epitopes may offer protection against the novel pneumonia COVID-19.

The team, led by data scientists Matthew McKay and Ahmed Abdul Quadeer, expect their work to help guide development of effective vaccines against SARS- CoV-2.
"Despite similarities between SARS-CoV and SARS-CoV-2, there is genetic variation between the two. And, it is not obvious if epitopes that elicit an immune response against SARS-CoV will be effective against SARS-CoV-2.

We found roughly 20% of the SARS-CoV epitopes map identically to SARS-CoV-2, and believe these to be promising."

Matthew R. McKay PhD, Department of Electronic and Computer Engineering, & Technology; Department of Chemical & Biological Engineering, The Hong Kong University of Science and Technology, Hong Kong, China.

Estimates of population coverage represent a percentage of individuals in the selected population likely to elicit an immune response - to at least one epitope from the identified set.
"To identify T cell epitopes, we performed a 'population coverage analysis', and determined a set of epitopes estimated to provide broad coverage globally, as well as in China."

Ahmed A. Quadeer PhD candidate, Department of Electronic & Computer Engineering, Hong Kong University of Science and Technology, Hong Kong, China.

The findings were recently published in the scientific journal Viruses.

The estimated population coverage represents a percentage of individuals within a selected population likely to elicit an immune response to at least one epitope from the identified set.
"Our objective was to assist with the initial phase of vaccine development, by providing recommendations of specific epitopes to be considered for incorporation into vaccine design.

Generally, our work is part of a global effort seeking to capitalize on data for COVID-19 - which is then made available and rapidly shared by the scientific community - to come up with effective interventions."

Matthew McKay.

The beginning of 2020 has seen the emergence of COVID-19 outbreak caused by a novel coronavirus, Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). There is an imminent need to better understand this new virus and to develop ways to control its spread. In this study, we sought to gain insights for vaccine design against SARS-CoV-2 by considering the high genetic similarity between SARS-CoV-2 and SARS-CoV, which caused the outbreak in 2003, and leveraging existing immunological studies of SARS-CoV. By screening the experimentally-determined SARS-CoV-derived B cell and T cell epitopes in the immunogenic structural proteins of SARS-CoV, we identified a set of B cell and T cell epitopes derived from the spike (S) and nucleocapsid (N) proteins that map identically to SARS-CoV-2 proteins. As no mutation has been observed in these identified epitopes among the 120 available SARS-CoV-2 sequences (as of 21 February 2020), immune targeting of these epitopes may potentially offer protection against this novel virus. For the T cell epitopes, we performed a population coverage analysis of the associated MHC alleles and proposed a set of epitopes that is estimated to provide broad coverage globally, as well as in China. Our findings provide a screened set of epitopes that can help guide experimental efforts towards the development of vaccines against SARS-CoV-2.

Syed Faraz Ahmed, Ahmed A. Quadeer and Matthew R. McKay.

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The authors declare no competing financial interests.

D.G. co-designed the study, undertook all experiments with human materials, evaluated the results and co-wrote the manuscript; P.F. co-designed the study, was attending physician to the clinical trial to which the study is annexed, provided human samples, evaluated clinical data and edited the manuscript; A.V. undertook the immunohistology; M.-L.M. undertook the animal model experiments; N.J.S. evaluated immunohistology and provided samples; K.C. designed and supervised the clinical trial to which the study is annexed and edited the manuscript; R.C. co-formulated the study as an annex to a clinical trial and edited the manuscript; N.K. co-supervised the analysis of pathology and edited the manuscript; A.H. co-designed the study, evaluated the results and co-wrote the manuscript.

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Mar 18 2020   Fetal Timeline   Maternal Timeline   News 

B cell epitopes that map identically to SARS-CoV-2.
CREDIT Hong Kong University of Science and Technology (HKUST).

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