High-Affinity alpha(5)beta(1)-Integrin-Selective Bicyclic RGD Peptides Identified via Screening of Designed Random Libraries
| Autor: | Peter Timmerman, Vanessa Jungbluth, Kees Jalink, Dominik Bernhagen, Paul B. White, Jakub Dostalek, Nestor Gisbert Quilis |
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| Přispěvatelé: | Molecular Cytology (SILS, FNWI), Synthetic Organic Chemistry (HIMS, FNWI) |
| Rok vydání: | 2019 |
| Předmět: |
chemistry.chemical_classification
biology Bicyclic molecule 010405 organic chemistry Stereochemistry Integrin Peptide Synthetic Organic Chemistry General Chemistry General Medicine 010402 general chemistry 01 natural sciences In vitro 0104 chemical sciences Amino acid law.invention chemistry Confocal microscopy law biology.protein Selectivity IC50 |
| Zdroj: | Acs Combinatorial Science, 21, 8, pp. 598-607 ACS Combinatorial Science, 21(8), 598-607. American Chemical Society Acs Combinatorial Science, 21, 598-607 |
| ISSN: | 2156-8952 |
| Popis: | We report the identification of high-affinity and selectivity integrin α5β1-binding bicyclic peptides via “designed random libraries”, that is, the screening of libraries comprising the universal integrin-binding sequence Arg-Gly-Asp (RGD) in the first loop in combination with a randomized sequence (XXX) in the second loop. Screening of first-generation libraries for α5β1-binding peptides yielded a triple-digit nanomolar bicyclic α5β1-binder (CT3RGDcT3AYGCT3, IC50 = 406 nM). Next-generation libraries were designed by partially varying the structure of the strongest first-generation lead inhibitor and screened for improved affinities and selectivities for this receptor. In this way, we identified three high-affinity α5β1-binders (CT3RGDcT3AYJCT3, J = D-Leu, IC50 = 90 nM; CT3RGDcT3AYaCT3, IC50 = 156 nM; CT3RGDcT3AWGCT3, IC50 = 173 nM), of which one even showed a higher α5β1-affinity than the 32 amino acid benchmark peptide knottin-RGD (IC50 = 114 nM). Affinity for α5β1-integrin was confirmed by SPFS analysis showing a Kd of 4.1 nM for Cy5-labeled RGD-bicycle CT3RGDcT3AYJCT3 (J = D-Leu) and a somewhat higher Kd (9.0 nM) for Cy5-labeled knottin-RGD. The α5β1-bicycles, for example, CT3RGDcT3AYJCT3 (J = D-Leu), showed excellent selectivities over αvβ5 (IC50 ratio α5β1/αvβ5 between 50 ratios α5β1/αvβ3 between 0.090 and 0.157). In vitro staining of adipose-derived stem cells with Cy5-labeled peptides using confocal microscopy revealed strong binding of the α5β1-selective bicycle CT3RGDcT3AWGCT3 to integrins in their natural environment, illustrating the high potential of these RGD bicycles as markers for α5β1-integrin expression. |
| Databáze: | OpenAIRE |
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