Aptamere | Universitätsklinikum Tübingen

Aptamers

Cell-specific aptamers

Aptamers are short single-stranded RNA or DNA oligonucleotides (25-90 nucleotides). Their three-dimensional structure allows them to bind their target molecules with a high affinity and specificity. The enormous number of possible tertiary structures allows aptamers to recognize and bind small molecules, peptides, proteins, or even complex structures, such as entire cells, bacteria, or viruses.

The dissociation constants (K_d) are in the low picomolar to the nanomolar range, comparable and often even better than that of monoclonal antibodies.

Contact

frontend.sr-only_#{element.contextual_1.children.icon}: Prof. Dr. Meltem Avci-Adali Head of Department

frontend.sr-only_#{element.contextual_1.children.icon}: 07071 29-86605

frontend.sr-only_#{element.contextual_1.children.icon}: 07071 29-5369

The group is working on the generation of DNA aptamers against endothelial progenitor cells (EPCs), cancer cells, and other cell types to isolate, accumulate, and target these cells. To obtain highly specific and selective aptamers for cells, the combinatorial chemistry method SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is used (see Figure). Enrichment of cell-specific aptamers occurs from a huge oligonucleotide library of up to 10¹⁵ molecules.

We have several years of experience in the following areas:

Isolation, cultivation, and characterization of human and porcine stem cells
Molecular biology techniques for performing cell and protein SELEX experiments, e.g. PCR, qRT-PCR, single-stranded DNA generation, gel electrophoresis, cloning, flow cytometry, and NGS
Evaluation of the generated aptamers

Selected publications:

Kunnakattu, S.J., Hann, L., Kurz, J., Haag, H., Fennrich, S., Rauch, N., Schlensak, C., Wendel, H.P., Stoppelkamp, S*. and Avci-Adali, M*., 2020. Application of Piezo-Based Measuring System for Evaluation of Nucleic Acid-Based Drugs Influencing the Coagulation. Sensors, 20(1), 152.
Stoll H, Steinle H, Wilhelm N, Hann L, Kunnakattu SJ, Narita M, Schlensak C, Wendel HP, Avci-Adali M. Rapid Complexation of Aptamers by Their Specific Antidotes. (2017) Molecules, 22(6).
Stoll H, Kiessling H, Stelzle M, Wendel HP, Schütte J, Hagmeyer B*, Avci-Adali M*. Microfluidic chip system for the selection and enrichment of cell binding aptamers. (2015) Biomicrofluidics. 9(3), 034111.
Haller C, Sobolewska B, Schibilsky D, Avci-Adali M, Schlensak C, Wendel HP, Walker T. One-staged aptamer-based isolation and application of endothelial progenitor cells in a porcine myocardial infarction model. (2015) Nucleic Acid Ther. 25(1):20-6.
Avci-Adali M, Steinle H, Michel T, Schlensak C, Wendel HP. Potential capacity of aptamers to trigger immune activation in human blood. (2013) PLoS One. ;8(7):e68810.