Doctor of Philosophy, The Ohio State University, 2022, Biomedical Engineering

Gene therapies have provided researchers with the possibility of manipulating transcription factors (TFs) that can regulate gene expression in cells, resulting in cellular reprogramming. This opportunity has clear biomedical applications, allowing the development of therapeutical approaches that can treat multiple diseases at their root. Viral vectors have emerged as the most widely used carriers for delivering molecular tools to target cells. However, the use of viral vectors presents undesirable side effects and other problems that prevent this method from being an effective mechanism of delivery to target cells if we want to provide a clinical effect. The objective of my research was to develop a nucleic acid delivery system using extracellular vesicles (EVs) for targeted payload delivery, which will cause cellular reprogramming of specific cell types overcoming the disadvantages presented by the use of viral vectors. I hypothesized that the expression of specific TFs will promote phenotypic conversion of cells. I developed and implemented an endogenous EV loading approach by engineering fibroblasts as a cell source for the production of EVs loaded with ABM and PNM TFs. To achieve the loading of EVs, fibroblasts were electroporated as the transfection method to incorporate plasmid DNA encoding for TFs of interest. The EVs produced were loaded with these TFs. To convert fibroblasts into neurons, EVs were loaded with Ascl1, Brn2 and Myt1l (ABM) genes, whereas to stimulate conversion of pancreatic ductal cells to insulin producing cells EVs were loaded with Pdx1, Neurog3 and MafA (PNM) genes. Also, I developed a method to decorate EVs with molecules that would only be recognized by target cells, enhancing specificity of the expression of the TFs, which potentially avoids off-target effects. Results showed that that the target cells incorporated the EVs and expressed the TFs. The expression of these TFs elicited the production of the desired ph (open full item for complete abstract)

Committee: Natalia Higuita-Castro (Advisor); Kristin Stanford (Committee Member); Daniel Gallego Perez (Committee Member) Subjects: Biomedical Engineering; Biomedical Research

Doctor of Philosophy, Case Western Reserve University, 2022, Biomedical Engineering

Vascular pathologies, such as myocardial infarction, stroke, and pulmonary embolism, are major causes of morbidities and mortalities in the US and globally. A primary event in such pathologies is the formation of an occlusive clot in the blood vessel, preventing blood flow. Current clinical treatment involves intravascular administration of plasminogen activators (PA) for rapid recanalization of the blood vessel. However, systemic administration of such drugs can have off-target drug action, which affects hemostatic capabilities and can lead to substantial hemorrhagic risks. Therefore, there is significant clinical interest in strategies for enhanced drug delivery to clots while minimizing systemic effects. One such strategy is the utilization of drug-carrying nanoparticles surface-decorated with clot-binding ligands. To this end, I hypothesize that thrombolytic drug-loaded nanoparticles delivered intravenously that can bind and anchor to the clot site under flow and undergo site-specific degradation for localized payload release can enhance targeted thrombolytic efficacy while minimizing off-target side effects. To test this hypothesis, I have developed multiple lipid-based nanoparticle platforms for targeted thrombolysis. For the first technology, a lipid nanovesicle was developed that could protect encapsulated thrombolytic drug streptokinase from off-target action, anchor to platelets in the clot, and allow localized drug release via clot-relevant enzyme phospholipase A2. This platform demonstrated similar levels of thrombolysis while minimizing systemic hemorrhaging in a FeCl3-induced thrombosis mouse model. The second technology improved upon the clot-targeting aspect, demonstrating that combination targeting of both platelets and fibrin enhanced clot-anchorage compared to targeting either clot component individually. Finally, in the last technology, I designed a thrombin-responsive nanoparticle platform that binds to both platelets and fibrin, encapsulated pl (open full item for complete abstract)

Committee: Anirban Sen Gupta (Advisor); Kandice Kottke-Marchant (Committee Member); Xin Yu (Committee Member); Steven Eppell (Committee Chair) Subjects: Biomedical Engineering

Doctor of Philosophy, The Ohio State University, 2022, Chemistry

Peptide self-assembly offers a powerful tool in the development of nanomedicines. We present a CPT based tetrapeptide scaffold, containing cysteines, which offers high stability and controlled release at low concentrations due to the crosslinking disulfides. The inclusion of cysteines allows for crosslinking under oxidative conditions (10% DMSO in PBS). The formation of covalent bonds allows for the structure to remain intact even at low concentrations and provides an opportunity to control the release of CPT. Many cancers are known to overexpress reducing agents, GSH, which would selectively break the disulfide bonds to release the CPT in the presence of cancer cells. Dual drug delivery systems have the potential to be a powerful tool in the treatment of cancers. Currently, combinations of anticancer agents are prescribed together, in many instances, 5-Fu and irinotecan are used together. We present a dual drug scaffold using both 5-Fu and CPT that can quickly release 5-Fu, while a secondary structure forms to afford the slow release of CPT. The initial system is assembled into a nanotube with a diameter of 84 nm, and as the 5-Fu is released, the nanotubes morph into a second assembly with a diameter of 72 nm that allows the CPT to be released more slowly. Previous studies have demonstrated peptide based self-assembled system can have a stabilizing effect on enzymes. We report the use of electro-spun CNCs, graciously given to us by the National Research Council of Canada, to test the long-term stability of Rubisco over the period of 49 days. Further studies are warranted to determine the potential use of PDA as a polymer coat of the CNC scaffolds.

Committee: Jonathan Parquette (Advisor); Christopher Hadad (Committee Member); Jovica Badjic (Committee Member) Subjects: Chemistry

Doctor of Philosophy, Case Western Reserve University, 2020, Biomedical Engineering

The high morbidity associated with triple negative breast cancers (TNBCs) is directly related to its high risk of recurrence. TNBC recurrence is often invasive - leading to its metastasis (mTNBC) in visceral organs including the lungs, liver, and brain. With these phenotypic characteristics nearly all newly diagnosed patients with mTNBC will have a poor prognosis. The difficulty with metastatic disease is two-fold: 1) micrometastasis (> 1cm) cannot be reliably detected by conventional diagnostic techniques and 2) therapeutic windows are reduced as the metastatic lesions are not easily accessible to systemically administered agents. Thus, the difficulty in diagnosis and treatment lies to a great degree in adequately targeting imaging and therapeutic agents to metastasis. However, it is well documented that metastatic niches upregulate receptors that are not commonly found in healthy tissues such as nonendogenous matrix proteins (i.e. PTP-mu, fibronectin/fibrinogen), adhesion molecules (i.e. selectins, cadherins and integrins) and cell specific markers (i.e. EGFR and integrins). Nanotechnology offers a unique solution such by incorporating targeting ligands that can direct nanoparticles to these tumor-associated upregulated biomarkers. By decorating the surface of nanoparticles with targeting moieties, we can adequately administer nanoparticles loaded with either contrast agents, chemotherapeutics or immunotherapeutics. In this dissertation, we show that targeted nanoparticles can significantly improve diagnosis and treatment of metastatic breast cancer.

Committee: Efstathios Karathanasis Ph.D. (Advisor); Capadona Jeffery Ph.D. (Committee Chair); Yu Jennifer M.D., Ph.D. (Committee Member); Tiwari Pallavi Ph.D. (Committee Member); Samia Anna Ph.D. (Committee Member) Subjects: Biomedical Engineering

Doctor of Philosophy, Case Western Reserve University, 2019, Pathology

Traumatic non-compressible hemorrhage and coagulopathy remain leading causes of civilian and military mortalities, especially in pre-hospital and limited resource scenarios. Patients with thrombocytopenia are at an even higher risk due to their low number of platelets, a major blood component involved in clotting. Current clinical strategy to treat this involves massive transfusion of whole blood or blood components (e,g. RBC: platelet: plasma at 1:1:1 ratio), but such blood products present issues of limited availability and portability, high risk or contamination and short shelf-life, that substantially limit their widespread use in resource-limited scenarios. Therefore, there remains a significant need for intravenous hemostatic products that allow hemorrhage control and coagulopathy mitigation, while avoiding the above issues associated with blood-derived products. To address this need, my research has focused on developing an I.V.-administrable platelet-inspired nanomedicine system for the hemostatic management of bleeding complications in thrombocytopenia and trauma. To this end, the primary focus of this dissertation is on evaluating the mechanism, safety and efficacy of platelet-inspired nanomedicine systems in the hemostatic management of clinically relevant bleeding complications. My overall hypothesis is that the design of nanoscale delivery systems with platelet-inspired heteromultivalent surface-modifications, can enable injury site-specific biointeractions and drug delivery to enhance platelet-mediated hemostatic processes, leading to decreased blood loss and increased survival. I have tested this hypothesis in two platelet-inspired nanomedicine designs: (i) in a synthetic nanoparticle based functional mimic of platelets (termed SynthoPlateTM) that can leverage and amplify the body's physiological clotting mechanisms specifically at the bleeding site and (ii) in a platelet-inspired nanovehicle for injury-site targeted delivery of hemostasis augmentin (open full item for complete abstract)

Committee: Anirban Sen Gupta PhD (Advisor); Nicholas Ziats PhD (Committee Chair); James Anderson MD, PhD (Committee Member); Howard Meyerson MD (Committee Member); Agata Exner PhD (Committee Member); Clive Hamlin PhD (Committee Member) Subjects: Biomedical Engineering; Pathology

Master of Sciences, Case Western Reserve University, 2017, Biomedical Engineering

Lung cancer is the leading cause of cancer-related mortalities in the USA with a five-year survival rate of ~15%. For patients with Non-Small-Cell Lung Cancer (NSCLC), chemotherapy, oncogene targeted therapy, or immunotherapy are the primary modes of treatment. Response rates to immunotherapies for NSCLCs are < 20%, due to the tumor micro-environment (TME) that favors immune-evasion and pro-tumorigenic pathways such as macrophage polarization from a pro-inflammatory (M1) to a pro-tumorigenic/angiogenic (M2) phenotype. Additionally, the TME is compromised by the chronic enzymatic breakdown of the elastic matrix which catalyzes polarization. Exogenous delivery of Doxycycline (DOX) has shown to inhibit the M1-M2 phenotypic switch. We explored the utility of antibody-conjugated DOX-poly(ethylene glycol)-poly(lactic glycolic-acid) (PEG-PLGA) nanoparticles (NPs) to inhibit macrophage polarization and demonstrate that steady-state release of DOX from these NPs is possible in a low dose range to inhibit polarization and repolarize macrophages back to the M1 phenotype.

Committee: Anand Ramamurthi (Advisor); Eben Alsberg (Committee Member); Colin Drummond (Committee Member) Subjects: Biomedical Engineering; Biomedical Research; Polymer Chemistry; Polymers

Master of Sciences (Engineering), Case Western Reserve University, 2017, Biomedical Engineering

Platinum resistance in ovarian cancer is the major determinant of disease prognosis. Resistance can first appear at the onset of disease or develop in platinum-sensitive (PS) disease in response to platinum-based chemotherapy. Due to poor response to alternative therapies, there is an urgent clinical need for a new avenue towards treatment of platinum-resistant (PR) ovarian cancer. Improved delivery systems may circumvent such resistant mechanisms and accelerate translation of existing drugs. In this work, I present a novel platform, tobacco mosaic virus (TMV), as a nanocarrier for cisplatin for treatment of PR ovarian cancer. A reliable method for preparation of the TMV-cisplatin conjugate (TMV-cisPt) was optimized and the cisplatin release was characterized. Efficient uptake in cancer cells in vitro was observed within 15 hours, and TMV-cisPt demonstrated superior cytotoxicity in PS and PR cancer cells when compared to free cisplatin. The cytotoxicity in PR cells and overall lower effective dosage requirement makes TMV-cisPt a potentially powerful system for improved ovarian cancer treatment.

Committee: Nicole Steinmetz Ph.D. (Committee Chair); Horst von Recum Ph.D. (Committee Member); Analisa DiFeo Ph.D. (Committee Member); Sourabh Shukla Ph.D. (Committee Member) Subjects: Biomedical Engineering; Biomedical Research; Medicine; Molecular Chemistry; Nanoscience; Nanotechnology; Oncology; Pharmaceuticals; Therapy; Virology

Doctor of Philosophy, Case Western Reserve University, 2016, Biomedical Engineering

Nanomedical approaches are of great interest due to their potential for specifically delivering packaged contrast agents and drugs to sites of disease while avoiding healthy tissue. Non-mammalian viruses, which are noninfectious to humans, can be used as unique nanoscale scaffolds with many advantages for nanotechnology and biomedicine. Compared to synthetically programmed materials, these particles can be precisely arranged into a diverse array of shapes and sizes, and there are many available avenues for easy and reproducible modification. Here, I investigated the expansion of the potential of these viruses for diverse applications in nanomedicine. First, I demonstrated the capability for interior engineering of a well-known icosahedral plant virus, cowpea mosaic virus (CPMV), for the encapsulation of a range of molecules, including fluorophores to enable optical imaging in the setting of cancer detection and diagnosis. Then, some design considerations were examined for the use of nanoparticles for fluorescence imaging, which informed our choices for subsequent studies. Dye density, dye localization, conjugation method, and cell uptake were all found to affect the resultant fluorescence intensity with the optimal design parameters being: non-aromatic linker chemistries, exterior particle conjugation, and dye spacing of around 8-10 nm. A second set of studies explored drug delivery using virus-based particles, demonstrating their utility for photodynamic therapy through solubilization of highly hydrophobic photosensitizers as well as for the treatment of chronic infections through using their native tropism. Finally, as increasing evidence suggest that shape is an important parameter for cell and tissue interactions, we explored the effect of aspect ratio and shape in mediating cell uptake and targeting the vessel wall. Nanoparticle chains were created, with clear differences seen in cell uptake due to shape-based as well as avidity effects. Additionally, in a para (open full item for complete abstract)

Committee: Horst von Recum Ph.D. (Committee Chair); Nicole Steinmetz Ph.D. (Advisor); Stuart Rowan Ph.D. (Committee Member); Daniel Simon M.D. (Committee Member) Subjects: Biomedical Engineering; Nanotechnology

MS, University of Cincinnati, 2015, Engineering and Applied Science: Materials Science

Cancer is one of the serious public health problems in the world. In order to reduce the side effect of the traditional cancer therapies, such as chemotherapy and radiotherapy, researchers have been working on developing new cancer treatments and photothermal therapy (PTT) is one of them. Irradiated by a NIR laser, nanoparticles targeted in the tumor tissue can generate heat. When the temperature is above 42°C, the tumor regions will begin to become ablated. Compared with the traditional therapy, PTT could increase the specificity of the treatment and reduce the side effects. Iron oxide magnetic nanoparticles are widely used for PTT due to their stability and multimodal functionality. The stability and innate toxicity of PS coated and uncoated nanoparticles were evaluated and it was found that PS coating significantly increases the stability and reduces the innate toxicity. Furthermore, hyperthermic ablation of MDA-MB-231 due to the photothermal effect of PS coated nanoparticles was observed. This observation was made using a 785 nm NIR laser for irradiation. The tissue-depth is of a concern for clinical therapy because the body tissues can absorb NIR laser. An agar gel layer was used to mimic the body tissue. The transmittance of laser through agar gel layers of varying thickness were examined and the effect of the tissue depth on hyperthermic ablation was evaluated. The absorbance of NIR light increases as the agar gel depth increases and as a result viability decreases. However, the significant viability loss was still observed at 3cm agar gel layer, indicates that the thickness of agar gel layer has a limiting impact on hyperthermia ablation of MDA-MB-231.

Committee: Donglu Shi Ph.D. (Committee Chair); David Mast Ph.D. (Committee Member); Giovanni Pauletti Ph.D. (Committee Member); Vesselin Shanov Ph.D. (Committee Member) Subjects: Materials Science

Doctor of Philosophy, Case Western Reserve University, 2014, Molecular Medicine

Advanced-stage prostate cancer is associated with metastasis to lymph nodes and bones and is untreatable with chemotherapy because of poor distribution of intravenously administered anticancer drugs to these tissues. In this dissertation, biodegradable nanoparticles (NPs) formulated from poly (D,L-lactide co-glycolide) were explored for drug delivery to primary tumor and metastasis sites. It was hypothesized that modulation of physical characteristics of NPs coupled with effective routes of administration can enhance targeting of therapeutics to primary and metastasized tumor sites. To target primary tumor and lymph nodes, lymphatic delivery of NPs through subcutaneous (SQ) and intramuscular (IM) injection was investigated. NPs (170 nm) with anionic surface charge injected SQ effectively targeted multiple lymph nodes along a lymphatic tract, drained into the blood and localized into primary tumor at 14-fold greater accumulation than intravenous (IV) injection. A single dose SQ injection of paclitaxel (PTX) loaded NPs (PTX-NP) significantly decreased tumor burden in prostate cancer xenograft model and improved survival of tumor bearing mice than IV injection of PTX-NP, PTX in Cremophor/ethanol or saline control. Further, SQ injection of NPs resulted in greater accumulation of NPs in metastasized lymph node and inhibited the progression of the metastasis better than other treatments. For targeting NPs treat bone metastasis, the sinusoidal capillaries of bone marrow were exploited. NPs with neutral surface charge demonstrated greater localization in bone marrow than anionic and cationic NPs. In an intraosseous model of bone metastasis, neutral NPs demonstrated greater accumulation in bone with metastasis than normal bone and a single-dose IV injection of PTX-loaded neutral NPs significantly inhibited the progression of bone metastasis and prevented bone loss. In addition, PTX in NPs did not cause acute toxicity, as the animals gained weight, whereas those treat (open full item for complete abstract)

Committee: Vinod Labhasetwar Ph.D. (Advisor) Subjects: Biomedical Engineering; Biomedical Research

PhD, University of Cincinnati, 2012, Engineering and Applied Science: Biomedical Engineering

RNA nanotechnology is to extract defined RNA structure motifs and tertiary interactions, apply them as the building blocks to self-assemble nano-scaled scaffolds with rational designs, and incorporate functional molecules such as siRNA, ribozyme, aptamer and therapeutical compounds to form functionalized RNA nanoparticles. Bacteriophage phi29 packaging RNA (pRNA) has two defined domains: the 5'/3'-end helical domain and the interlocking loop region which is located at the central part of the pRNA sequence. pRNA dimer is formed by hand-in-hand interaction via 4-bp interlocking base pairing. The dimeric pRNA nanoparticle has been shown to be an efficient vector for the specific delivery of small interfering RNA (siRNA) into specific cancer or viral infected cells. However, there are several problems hindering the therapeutic applications of pRNA nanoparticles. In this thesis, I will try to address: 1) The problem of large-scale synthesis of longer RNA molecules. Industrial scale production of RNA by chemical synthesis is limited to ~ 80nt. In order to chemically synthesize pRNA and its functionalized chimeric constructs (generally > 120 nt) in large scales, pRNA nanoparticles were constructed using two synthetic RNA fragments within the size limit for chemical synthesis. The resulting bipartite pRNAs were competent to form dimers, package DNA via the nanomotor, and assemble phi29 phage in vitro. The pRNA subunit assembled from bipartite fragments harboring siRNA or receptor-binding ligands were equally competent in binding cancer cells specifically, entering the cell, and silencing specific genes of interest as the intact constructs. 2) The problem of RNA degradation. 2'-fluorine (2'-F) modification was introduced into the RNA sugar ring and the modified RNAs were resistant to RNase degradation and suitable for in vivo delivery. 3) The dissociation problem of pRNA nanoparticles. The lack of covalent linkage or crosslinking in nanoparticles causes dissociation of pRNA (open full item for complete abstract)

Committee: Jing-Huei Lee PhD (Committee Chair); Peixuan Guo PhD (Committee Member); Andrew Herr PhD (Committee Member); Malak Kotb PhD (Committee Member) Subjects: Biomedical Research

PhD, University of Cincinnati, 2012, Engineering and Applied Science: Biomedical Engineering

Linear double-stranded DNA (dsDNA) viruses package its genome into a preformed procapsid fueled by the energy from ATP hydrolysis. The bacteriophage phi29 motor has a truncated cone shaped protein component, named connector, with a central channel of 3.6 nm at its narrowest part. The connector protein has been successfully inserted into an artificial lipid bilayer membrane, and the channel exhibited robust capability under various salt and pH conditions as revealed by single channel studies. This channel is suitable for extremely precise assessment of the transportation of small molecules, such as ions, DNA and RNA. There is an urgent need to development a highly sensitive detection system, for the applications in the area of pathogen detection, disease diagnosis, environmental monitoring, etc. The current challenges and limitations of these technologies are the sensitivity and accuracy issues arising from background noise and nonspecific reactions. The property of phi29 motor channel has been studied at various conditions, and was incorporated into lipid membrane. The motor channel exercised a one-way traffic property during the process of dsDNA translocation with a valve mechanism. In addition, the opening and closure of the channel also exhibit reversible and controllable. A modified version of the connector channel is founded to have a smaller channel size, which is able to detect the ssDNA and ssRNA. These findings have important implications since this artificial membrane-embedded channel would allow detailed investigations into the mechanisms of viral motor operation, as well as future applications for therapeutic molecule packaging, delivery, single molecule sensing and drug screening.

Committee: Jing-Huei Lee PhD (Committee Chair); Chong Ahn PhD (Committee Member); Peixuan Guo PhD (Committee Member); Jaroslaw Meller PhD (Committee Member); Marepalli Rao PhD (Committee Member) Subjects: Biomedical Research

Doctor of Philosophy, The Ohio State University, 2005, Biomedical Engineering

The work presented herein describes the investigation in several key areas related to imaging and image-guided therapy. Each area is of interest for advancing the state of the art and development of new techniques in image-guided therapy. First, the rationale and approaches for microfabrication of microparticles is advanced. A technique for microfabrication of biodegradable mircorparticles of tailorable geometry and monodisperse size is described as well as efforts and the design of an experimental set-up to optimize production. The applications of such microparticles as drug delivery vehicles or as agents for embolization (or both as in chemoembolization) make them a promising technology in image-guided therapy. A second related focus of study is presented in the area of quantitative diagnostics. Combining imaging techniques and analysis algorithms can both identify and quantify disease states. Precise determination the extent of disease can be used to gage response to therapy, i.e. provide outcome measures to develop new therapies, including those advanced by image-guidance. A novel imaging method for identification of disease states of the major airways and lungs in pediatric populations is presented. Lastly, an animal model suitable for the testing of therapies directed against lymphatic malformations and lymphangiogenesis is presented. This method of site-specific induction of de novo lymphatic malformations (LMs) expressing specific growth factor receptors will allow investigations in the function and formation of lymphatic vessels. Macrocystic LMs observed in this model are shown to be large enough to target using current image-guided approaches (sclerotherapy) to optimize treatment capabilities. Microcystic LMs are also induced in this model, which might allow development of therapy against this variant. The LMs cysts have promise as bioreactors to test particle-based therapies directed against lymphatic endothelium. Each of the presented areas has bearing f (open full item for complete abstract)

Committee: Derek Hansford (Advisor) Subjects:

Master of Science in Engineering, University of Akron, 2008, Biomedical Engineering

Statistical figures outline the five-year survival rate for all cancers diagnosed between 1996 and 2002 as 66%, which depicts a marked rise from the 51% that survived in 1975-1977 (1). However, cancer still remains the second leading cause of death in the United States, following heart disease. An American Cancer Society report estimated that in 2007, there will be over 1.4 million new cancer cases and over half a million cancer deaths in the United States (1). Although significant oncology drug discoveries have been made during the past 30 years, conventional chemotherapeutic agents exhibit poor specificity in reaching the tumor site and are often restricted by toxicity factors. The lack of a uniform biodistribution leads to harmful side-effects to healthy tissues and the need for administration of a larger than necessary drug dosage with a higher repetitive rate so as to elicit a satisfactory pharmacological response. Wide interest in cancer nanotherapy has led to the development of nanoparticle based "smart drugs" that have not only improved pharmacological and therapeutic properties of anticancer drugs, but also offer a less invasive alternative enhancing the patient's life expectancy and quality of life as well. Dendrimers, due to their unique architecture and macromolecular characteristics are currently used extensively in research of nanoparticles for targeted and controlled drug delivery. The research objective was to design, synthesize and characterize a novel nanoparticle based "PAINT-BRUSH" like multi-hydroxyl capped poly (ethylene glycol) (PEG) conjugate using the dendron - bishomotris that may have a potential use in targeted cancer nanotherapy. Characterization of the conjugates suggested that the synthesis was successful; resulting in the formation of nanoparticle "PAINT-BRUSH" conjugates. It was also found that these conjugates remain stable under normal physiological conditions but would activate in response to an acidic pH (a characteristi (open full item for complete abstract)

Committee: Stephanie Lopina PhD (Advisor) Subjects: Biology; Biomedical Research; Chemical Engineering; Chemistry; Engineering; Pharmaceuticals

Doctor of Philosophy, Case Western Reserve University, 2013, Biomedical Engineering

Uncontrolled hemorrhage comprises 60-70% of trauma-associated mortality in the absence of other lethal conditions (e.g. damage to central nervous or cardiac system). Immediate intervention is critical to improving chances of survival. While there are several products to control bleeding for external wounds including pressure dressings, tourniquets or topical hemostatic agents there are few, if any, effective treatments that can be administered in the field to help staunch internal bleeding. Intravenous hemostatic nanoparticles that augment blood clotting when administered after trauma have been previously shown to half bleeding times in a femoral artery injury model in rats. The aims of the present study were to: 1) Determine their efficacy in a lethal hemorrhagic liver injury model, 2) determine the impact of targeting ligand concentration on hemostasis, and 3) test them in a clinically relevant porcine model of hemorrhage. Nanoparticle administration (GRGDS-NP1, 40 mg/kg) after lethal liver resection in the rat increased 1-hour survival to 80% compared to 40-47% in controls. Targeting ligand conjugation was then increased 100-fold (GRGDS-NP100), and a dosing study performed. GRGDS-NP100 hemostatic nanoparticles (2.5 mg/kg) were efficacious at doses 8-fold lower than GRGDS-NP1, and increased 1-hour survival to 92%. In vitro analysis using rotational thromboelastometry (ROTEM) confirmed the increased dose-sensitivity of GRGDS-NP100 and laid the foundation for methods to determine optimal ligand concentration parameters. Hemostatic nanoparticles were then tested in a clinically relevant porcine liver injury model, which elucidated an unexpected adverse reaction, comprised of a massive hemorrhagic response. A naive (uninjured) porcine model was then employed. These experiments revealed an adverse reaction consistent with complement activation related pseudoallergy (CARPA), which could be mediated by tuning nanoparticles' zeta potential. Neutralizing the nanopa (open full item for complete abstract)

Committee: Erin Lavik Sc.D. (Committee Chair); Jeffrey Ustin M.D. (Committee Member); Horst von Recum Ph.D. (Committee Member); Robert Miller Ph.D. (Committee Member) Subjects: Biomedical Engineering; Biomedical Research; Medicine