@article{krissanaprasit_mihalko_meinhold_simpson_sollinger_pandit_dupont_kjems_brown_labean_2024, title={A Functional RNA-Origami as Direct Thrombin Inhibitor with Fast-acting and Specific Single-Molecule Reversal Agents in vivo model}, volume={32}, ISSN={1525-0016}, url={http://dx.doi.org/10.1016/j.ymthe.2024.05.002}, DOI={10.1016/j.ymthe.2024.05.002}, abstractNote={Injectable anticoagulants are widely used in medical procedures to prevent unwanted blood clotting. However, many lack safe, effective reversal agents. Here, we present new data on a previously described RNA origami-based, direct thrombin inhibitor (HEX01). We describe a new, fast-acting, specific, single-molecule reversal agent (antidote) and present in vivo data for the first time, including efficacy, reversibility, preliminary safety, and initial biodistribution studies. HEX01 contains multiple thrombin-binding aptamers appended on an RNA origami. It exhibits excellent anticoagulation activity in vitro and in vivo. The new single-molecule, DNA antidote (HEX02) reverses anticoagulation activity of HEX01 in human plasma within 30 s in vitro and functions effectively in a murine liver laceration model. Biodistribution studies of HEX01 in whole mice using ex vivo imaging show accumulation mainly in the liver over 24 h and with 10-fold lower concentrations in the kidneys. Additionally, we show that the HEX01/HEX02 system is non-cytotoxic to epithelial cell lines and non-hemolytic in vitro. Furthermore, we found no serum cytokine response to HEX01/HEX02 in a murine model. HEX01 and HEX02 represent a safe and effective coagulation control system with a fast-acting, specific reversal agent showing promise for potential drug development.}, number={7}, journal={Molecular Therapy}, publisher={Elsevier BV}, author={Krissanaprasit, Abhichart and Mihalko, Emily and Meinhold, Katherine and Simpson, Aryssa and Sollinger, Jennifer and Pandit, Sanika and Dupont, Daniel M. and Kjems, Jørgen and Brown, Ashley C. and LaBean, Thomas H.}, year={2024}, month={May}, pages={2286–2298} }
 @article{kilgore_moore_sripada_chu_shastry_barbieri_hu_tian_petersen_mohammadifar_et al._2024, title={Peptide ligands for the universal purification of exosomes by affinity chromatography}, volume={8}, ISSN={["1097-0290"]}, DOI={10.1002/bit.28821}, abstractNote={Abstract Exosomes are gaining prominence as vectors for drug delivery, vaccination, and regenerative medicine. Owing to their surface biochemistry, which reflects the parent cell membrane, these nanoscale biologics feature low immunogenicity, tunable tissue tropism, and the ability to carry a variety of payloads across biological barriers. The heterogeneity of exosomes' size and composition, however, makes their purification challenging. Traditional techniques, like ultracentrifugation and filtration, afford low product yield and purity, and jeopardizes particle integrity. Affinity chromatography represents an excellent avenue for exosome purification. Yet, current affinity media rely on antibody ligands whose selectivity grants high product purity, but mandates the customization of adsorbents for exosomes with different surface biochemistry while their binding strength imposes elution conditions that may harm product's activity. Addressing these issues, this study introduces the first peptide affinity ligands for the universal purification of exosomes from recombinant feedstocks. The peptides were designed to (1) possess promiscuous biorecognition of exosome markers, without binding process‐related contaminants and (2) elute the product under conditions that safeguard product stability. Selected ligands SNGFKKHI and TAHFKKKH demonstrated the ability to capture of exosomes secreted by 14 cell sources and purified exosomes derived from HEK293, PC3, MM1, U87, and COLO1 cells with yields of up to 80% and up‐to 50‐fold reduction of host cell proteins (HCPs) upon eluting with pH gradient from 7.4 to 10.5, recommended for exosome stability. SNGFKKHI‐Toyopearl resin was finally employed in a two‐step purification process to isolate exosomes from HEK293 cell fluids, affording a yield of 68% and reducing the titer of HCPs to 68 ng/mL. The biomolecular and morphological features of the isolated exosomes were confirmed by analytical chromatography, Western blot analysis, transmission electron microscopy, nanoparticle tracking analysis.}, journal={BIOTECHNOLOGY AND BIOENGINEERING}, author={Kilgore, Ryan E. and Moore, Brandyn D. and Sripada, Sobhana A. and Chu, Wenning and Shastry, Shriarjun and Barbieri, Eduardo and Hu, Shiqi and Tian, Weihua and Petersen, Heidi and Mohammadifar, Mohammad and et al.}, year={2024}, month={Aug} }
 @article{simpson_krissanaprasit_chester_koehler_labean_brown_2024, title={Utilizing multiscale engineered biomaterials to examine <scp>TGF‐β</scp>‐mediated myofibroblastic differentiation}, volume={3}, ISSN={1067-1927 1524-475X}, url={http://dx.doi.org/10.1111/wrr.13168}, DOI={10.1111/wrr.13168}, abstractNote={AbstractCells integrate many mechanical and chemical cues to drive cell signalling responses. Because of the complex nature and interdependency of alterations in extracellular matrix (ECM) composition, ligand density, mechanics, and cellular responses it is difficult to tease out individual and combinatorial contributions of these various factors in driving cell behavior in homeostasis and disease. Tuning of material viscous and elastic properties, and ligand densities, in combinatorial fashions would enhance our understanding of how cells process complex signals. For example, it is known that increased ECM mechanics and transforming growth factor beta (TGF‐β) receptor (TGF‐β‐R) spacing/clustering independently drive TGF‐β signalling and associated myofibroblastic differentiation. However, it remains unknown how these inputs orthogonally contribute to cellular outcomes. Here, we describe the development of a novel material platform that combines microgel thin films with controllable viscoelastic properties and DNA origami to probe how viscoelastic properties and nanoscale spacing of TGF‐β‐Rs contribute to TGF‐β signalling and myofibroblastic differentiation. We found that highly viscous materials with non‐fixed TGF‐β‐R spacing promoted increased TGF‐β signalling and myofibroblastic differentiation. This is likely due to the ability of cells to better cluster receptors on these surfaces. These results provide insight into the contribution of substrate properties and receptor localisation on downstream signalling. Future studies allow for exploration into other receptor‐mediated processes.}, journal={Wound Repair and Regeneration}, publisher={Wiley}, author={Simpson, Aryssa and Krissanaprasit, Abhichart and Chester, Daniel and Koehler, Cynthia and LaBean, Thomas H. and Brown, Ashley C.}, year={2024}, month={Mar} }
 @article{simpson_shukla_brown_2022, title={Biomaterials for Hemostasis}, volume={24}, ISSN={1523-9829 1545-4274}, url={http://dx.doi.org/10.1146/annurev-bioeng-012521-101942}, DOI={10.1146/annurev-bioeng-012521-101942}, abstractNote={ Uncontrolled bleeding is a major problem in trauma and emergency medicine. While materials for trauma applications would certainly find utility in traditional surgical settings, the unique environment of emergency medicine introduces additional design considerations, including the need for materials that are easily deployed in austere environments. Ideally, these materials would be available off the shelf, could be easily transported, and would be able to be stored at room temperature for some amount of time. Both natural and synthetic materials have been explored for the development of hemostatic materials. This review article provides an overview of classes of materials used for topical hemostats and newer developments in the area of injectable hemostats for use in emergency medicine. }, number={1}, journal={Annual Review of Biomedical Engineering}, publisher={Annual Reviews}, author={Simpson, Aryssa and Shukla, Anita and Brown, Ashley C.}, year={2022}, month={Jun}, pages={111–135} }