This study was designed to characterize binding of a DNA aptamer to breast cancer cells and to test whether that aptamer could be used to kill target cells in vitro as part of an aptamer-C1q protein conjugate by coupling to the classic complement cascade. A biotinylated DNA aptamer designated MUC1-5TR-1 was shown to decorate the plasma membranes of human breast adenocarcinoma (MCF7) cells via f...

We assess the utility of integrating a predetermined aptamer DNA module adjacent to a random catalytic DNA region for identifying new deoxyribozymes by in vitro selection. By placing a known ATP aptamer next to an N40 random region, an explicitly modular DNA catalyst for tyrosine side chain phosphorylation is identified. The results have implications for broader identification of deoxyribozymes...

The DNA aptamer for adenosine (also for AMP and ATP) is a highly conserved sequence that has recurred in a few selections. It it a widely used model aptamer for biosensor development, and its nuclear magnetic resonance structure shows that each aptamer binds two AMP molecules. In this work, each binding site was individually removed by rational sequence design, while the remaining site still re...

Cytokines are of chief importance in the pathophysiology of sepsis and other systemic inflammatory response syndromes. We are designing and testing an extracorporeal cytokine adsorption device (CAD) that can remove cytokines via adsorption on biocompatible, microporous beads. The goal of this study was to determine whether a previously reported TNF binding DNA aptamer, 5’-GCGGCCGATA AGGTCTTTCC ...

Abstract Aptamers are single-stranded nucleic acids, typically 20-80 nucleobases (nb) in length, which can bind different compounds with high affinity and selectively. Their ligand-binding properties be attenuated by adding short complementary strands. These interactions open new opportunities for aptamer-based assays. Strong dependence between the length electrophoretic mobility of acids makes...

The present study used a spontaneous cell-based SELEX method (Systemic Evolution of Ligands by EXponential Enrichment) to produce DNA aptamers that specifically bind to cell surface proteins or biomarkers produced by primary cultured mouse tumor endothelial cells (mTECs). In solid tumors, new blood vessels are formed through an angiogenesis process, and this plays a critical role in cancer deve...

Remote control of aptamer function has allowed us to control protein function in space and time. Here, we propose a novel control system for aptamer function by radiofrequency magnetic field- (RFMF-) induced local heating of a gold nanoparticle conjugated with an aptamer. In this study, we used a 31-mer thrombin-binding aptamer (TBA), which can inhibit thrombin activity, as a model aptamer. We ...

Targeted drug delivery is important in cancer therapy to decrease the systemic toxicity resulting from nonspecific drug distribution and to enhance drug delivery efficiency. We have developed an aptamer-based DNA dendritic nanostructure as a multifunctional vehicle for targeted cancer cell imaging and drug delivery. The multifunctional DNA dendrimer is constructed from functional Y-shaped build...

We report an aptamer discovery technology that reproducibly yields higher affinity aptamers in fewer rounds compared to conventional selection. Our method (termed particle display) transforms libraries of solution-phase aptamers into "aptamer particles", each displaying many copies of a single sequence on its surface. We then use fluorescence-activated cell sorting (FACS) to individually measur...

The cocaine aptamer is a DNA three-way junction that binds cocaine at its helical junction. We studied the global conformation and overall flexibility of the aptamer in the absence and presence of cocaine by pulsed electron-electron double resonance (PELDOR) spectroscopy, also called double electron-electron resonance (DEER). The rigid nitroxide spin label Ç was incorporated pairwise into two h...