@article{nandi_sommerville_nellenbach_mihalko_erb_freytes_hoffman_monroe_brown_2020, title={Platelet-like particles improve fibrin network properties in a hemophilic model of provisional matrix structural defects}, volume={577}, ISSN={["1095-7103"]}, DOI={10.1016/j.jcis.2020.05.088}, abstractNote={Following injury, a fibrin-rich provisional matrix is formed to stem blood loss and provide a scaffold for infiltrating cells, which rebuild the damaged tissue. Defects in fibrin network formation contribute to impaired healing outcomes, as evidenced in hemophilia. Platelet-fibrin interactions greatly influence fibrin network structure via clot contraction, which increases fibrin density over time. Previously developed hemostatic platelet-like particles (PLPs) are capable of mimicking platelet functions including binding to fibrin fibers, augmenting clotting, and inducing clot retraction. In this study, we aimed to apply PLPs within a plasma-based in vitro hemophilia B model of deficient fibrin network structure to determine the ability of PLPs to improve fibrin structure and wound healing responses within hemophilia-like abnormal fibrin network formation. PLP impact on structurally deficient clot networks was assessed via confocal microscopy, a micropost deflection model, atomic force microscopy and an in vitro wound healing model of early cell migration within a provisional fibrin matrix. PLPs improved clot network density, force generation, and stiffness, and promoted fibroblast migration within an in vitro model of early wound healing under hemophilic conditions, indicating that PLPs could provide a biomimetic platform for improving wound healing events in disease conditions that cause deficient fibrin network formation.}, journal={JOURNAL OF COLLOID AND INTERFACE SCIENCE}, author={Nandi, Seema and Sommerville, Laura and Nellenbach, Kimberly and Mihalko, Emily and Erb, Mary and Freytes, Donald O. and Hoffman, Maureane and Monroe, Dougald and Brown, Ashley C.}, year={2020}, month={Oct}, pages={406–418} }
 @article{nandi_mohanty_nellenbach_erb_muller_brown_2020, title={Ultrasound Enhanced Synthetic Platelet Therapy for Augmented Wound Repair}, volume={6}, ISSN={["2373-9878"]}, DOI={10.1021/acsbiomaterials.9b01976}, abstractNote={Native platelets perform a number of functions within the wound healing process, including interacting with fibrin fibers at the wound site to bring about retraction after clot formation. Clot retraction improves clot stability and enhances the function of the fibrin network as a provisional matrix to support cellular infiltration of the wound site, thus facilitating tissue repair and remodeling after hemostasis. In cases of traumatic injury or disease, platelets can become depleted and this process disrupted. To that end, our lab has developed synthetic platelet-like particles (PLPs) that recapitulate the clot retraction abilities of native platelets through a Brownian-wrench driven mechanism that drives fibrin network densification and clot retraction over time, however, this Brownian-motion driven process occurs on a longer time scale than native active actin/myosin-driven platelet-mediated clot retraction. We hypothesized that a combinatorial therapy comprised of ultrasound stimulation of PLP motion within fibrin clots would facilitate a faster induction of clot retraction on a more platelet-mimetic time scale and at a lower dosage than required for PLPs acting alone. We found that application of ultrasound in combination with a subtherapeutic dosage of PLPs resulted in increased clot density and stiffness, improved fibroblast migration in vitro and increased epidermal thickness and angiogenesis in vivo, indicating that this combination therapy has potential to facilitate multiphase pro-healing outcomes. Additionally, while these particular studies focus on the role of ultrasound in enhancing specific interactions between fibrin-binding synthetic PLPs embedded within fibrin networks, these studies have wide applicability in understanding the role of ultrasound stimulation in enhancing multi-scale colloidal interactions within fibrillar matrices.}, number={5}, journal={ACS BIOMATERIALS SCIENCE & ENGINEERING}, author={Nandi, Seema and Mohanty, Kaustav and Nellenbach, Kimberly and Erb, Mary and Muller, Marie and Brown, Ashley C.}, year={2020}, month={May}, pages={3026–3036} }