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Published on: September 13, 2022
Peptide-based CE-SELEX enables convenient isolation of aptamers specifically recognizing CD20-expressing cells
Jordan Cossu1, Corinne Ravelet2, Véronique Martel-Frachet3
1University Grenoble Alpes, CNRS, DCM UMR 5250, 38058 Grenoble Cedex 9, France; University Grenoble Alpes, CNRS, DPM UMR 5063, 38041 Grenoble Cedex 9, France.
DNA aptamers targeting the CD20 antigen were developed using capillary electrophoresis-systematic evolution of ligands by exponential enrichment (CE-SELEX). These aptamers show specific binding to CD20-expressing cells, offering a promising alternative to monoclonal antibodies.
Area of Science:
- Biotechnology
- Molecular Biology
- Immunology
Background:
- The CD20 antigen is a significant therapeutic target for B-cell malignancies like lymphoma and autoimmune disorders.
- Monoclonal antibodies targeting CD20 have been used clinically for over two decades but face limitations including high cost and immunogenicity.
- Nucleic acid aptamers present an alternative therapeutic modality with potential advantages over antibodies.
Purpose of the Study:
- To develop and characterize DNA aptamers targeting the CD20 antigen.
- To evaluate the efficacy of a peptide-based Capillary Electrophoresis-Systematic Evolution of Ligands by Exponential Enrichment (CE-SELEX) method for aptamer selection.
- To demonstrate CE-SELEX as a viable alternative to traditional cell-based SELEX for discovering cell-targeting compounds.
Main Methods:
- Selection of DNA aptamers against CD20 using a peptide-based CE-SELEX approach.
- Characterization of aptamer binding specificity to CD20-expressing human cell lines.
- Quantification of aptamer-target affinity using isothermal titration calorimetry (ITC).
Main Results:
- Successfully selected DNA aptamers that specifically bind to CD20-expressing cells.
- Estimated dissociation constants (Kd) in the micromolar range, indicating moderate affinity.
- Demonstrated the suitability of CE-SELEX for identifying novel cell-targeting aptamers.
Conclusions:
- The peptide-based CE-SELEX method is effective for selecting DNA aptamers against cell surface targets like CD20.
- Selected aptamers exhibit specific binding to CD20-expressing cells, validating the CE-SELEX approach.
- CE-SELEX offers a valuable alternative to conventional cell-SELEX for aptamer discovery in therapeutic applications.
