Researchers from Bar-Ilan have identified an antigen that triggers an immune response towards finding a protein-based vaccine against the corona virus

In a study published in the journal VACCINES, researchers from Bar-Ilan University announced the discovery of a group of epitopes (a specific part of the antigen molecule that triggers an immune response) with immune potential in the protein envelope of the SARS-CoV-2 virus

In a study published in the journal VACCINES, researchers from Bar-Ilan University announced the discovery of a group of epitopes (a specific part of the antigen molecule that triggers an immune response) that have immune potential in the protein envelope of the SARS-CoV-2 virus. These epitopes are capable of eliciting an immune response both by antibody and by a humoral response mediated by the cell. The findings of this work may contribute to the development of a peptide vaccine (consisting of small proteins) against the infection with the SARS-CoV-2 virus and thus stop the spread of the COVID-19 epidemic and future pandemics caused by corona viruses.

The researchers led by Dr. Milena Frankel-Morgenstern, Director of the Department of Cancer Genomics and Bioinformatics of Complex Diseases at the Azrieli Faculty of Medicine at Bar-Ilan University, took a computer-based approach (bioinformatics) to study the information contained in the protein structure of the SARS virus. CoV-2 and thus managed to trace the location and identity of immunodominant sites of the virus. Immune responses based on dominant immunogenic epitopes are characterized by the attack of antigens presenting such epitopes both by antibody and by a mechanism mediated by the human cell. Such an immune response helps to quickly and effectively neutralize the pathogen.

The team of researchers, which also includes Sumit Mukherjee, Dmitry Taborovsky, Rajesh Detroja and Sunanda Biswas Mukherjee, identified 15 possible immunogenic regions across three proteins on the envelope surface of SARS-CoV-2 and mapped 25 immunodominant epitopes in other SARS-CoV-2 proteins.
To prove that these epitopes could be used to create a vaccine for the world population, the percentage of people expressing a major histocompatibility complex (MHC) capable of recognizing each of these epitopes was determined. Seven epitopes were found in over 87% of the world's population infected with the virus. An analysis of how these potential epitopes interact with the human MHC and the subsequent interactions was then performed. A complete list of MHC proteins that recognize each epitope was prepared, and this list is presented in the article describing the discovery and in the provisional patent application filed in the United States (US 63/034.416)).

The seven epitopes were tested using different methods to make sure that they are not allergenic or toxic and that they do not have an increased risk of causing auto-immune reactions. Overall, the results indicate that these seven epitopes are worthy candidates to be used as an effective vaccine. The development of a vaccine based on these immunodominant epitopes can manipulate both cellular and humoral immune response in humans who make up the majority of the world's population.

This research was supported by grants from the PBC Program for Postdoctoral Researchers from India and China and the Informatics Science Institute (DSI) of Bar-Ilan University. The Frankel-Morgenstern Group is currently seeking partners from industry and medical centers to advance its efforts to find a peptide-based vaccine against COVID-19.