Screening for COVID-19 T-cell peptides and immune monitoring with MHC tetramers in a single assay

COVID-19 infected cells can be recognized by T-cells only after SARS-CoV-2 peptides are processed and presented in the context of self MHCs.

Identifying these peptides have essential utilities:

• Immune monitoring: Using peptide-MHC tetramers to assess vaccine-induced immunity
• Designing potent vaccines that elicit durable responses

T-cells are activated only by interacting with processed peptides (e.g. of SARS-CoV-2) that sit in the groove of MHC Class I and II molecules. Identifying these peptides can be used (in forms of peptide-MHC tetramers) to assess vaccine induced immunity and assist in designing potent vaccines with durable responses.

MBL International can assist companies and academic investigators who are actively developing coronavirus vaccines with our unique QuickSwitch™ custom tetramer platform.  QuickSwitch™ is a peptide screening plug and play platform that identifies peptides that are more likely to be immunogenic and yet generates corresponding Class I and Class II MHC tetramers.  These platforms can identify and validate multi-epitope candidates of SARS-CoV-2 proteins that can potentially elicit for both CD4+ and CD8+ T-cell immune responses. In fact, the QuickSwitch™ custom tetramer kit has been used in peer-reviewed journals by Stephen J. Elledge and Steven A. Rosenberg teams ^1,2. 

Briefly, the protein sequence of SARS-CoV-2 is known and the predicted epitopes are identified and available published/reviewed by recent articles including one by Dr. Alex Sette: 

https://www.biorxiv.org/content/10.1101/2020.02.12.946087v2.full.pdf; https://marlin-prod.literatumonline.com/pb-assets/journals/research/cell-host-microbe/PDFs/CHOM_2264_S50.pdf

By using MBLI’s peptide screening MHC tetramer exchange QuickSwitch™ platform, you can identify/validate the binding of predicted peptide sequences of the COVID-19 viral proteins in most common alleles: H2Kb, A2, A11, A24, A3 and DR1, DR4, DR15. 

We can help to evaluate hundreds of predicted peptides for their ability to sit in the groove of MHC Class I and II with answers to the following points of inquiry:

1. Does your vaccine elicit T-cell responses in hosts?     

     a. Validating peptide binding affinities to multiple MHC Class I and II alleles.

     b. MHC tetramers for assessing and monitoring immune responses to individual peptides.

2. Information on immunogenic / protective peptides (vaccine design/fine tuning)

     a. Identifying and validating promiscuous MHC class II epitopes.

     b.Testing modified peptides on anchoring amino acids for optimal MHC binding and T-cell activation.

3. In addition, this platform can also be used in in vitro assays to identify immune-potentiating candidate agents for their ability to enhance vaccines potency.

Please contact us today for a personalized discussion to see how we can quickly help you gather accurate and relevant information for your research against COVID-19.

1. Kula, Tomasz, et al. “T-Scan: A Genome-Wide Method for the Systematic Discovery of T Cell Epitopes.” Cell, vol. 178, no. 4, 2019, doi:10.1016/j.cell.2019.07.009.
2. Lo, Winifred, et al. “Immunologic Recognition of a Shared p53 Mutated Neoantigen in a Patient with Metastatic Colorectal Cancer.” Cancer Immunology Research, vol. 7, no. 4, 2019, pp. 534–543., doi:10.1158/2326-6066.cir-18-0686.