A. James Clark School of Engineering
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The collections in this community comprise faculty research works, as well as graduate theses and dissertations.
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Item PREPARATION OF A NANOSUSPENSION OF THE PHOTOSENSITIZER VERTEPORFIN FOR PHOTODYNAMIC AND LIGHT-INDEPENDENT THERAPY IN GLIOBLASTOMA(2024) Quinlan, John Andrew; Huang, Huang-Chiao; Bioengineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Photodynamic therapy (PDT) using verteporfin (VP) has treated ocular disease for over 20 years, but recent interest in VP’s light-independent properties has reignited interest in the drug, particularly in glioblastoma (GBM) (NCT04590664). Separate efforts to apply PDT to GBM using 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) have also garnered attention (NCT03048240), but, unfortunately, clinical trials using 5-ALA-induced PpIX-PDT have yet to yield a survival benefit. Previous studies have shown VP to be a superior PDT agent than 5-ALA-induced PpIX. Our lab has shown that 690 nm light activates VP up to 2 cm into the brain, while 635 nm light only activates PpIX at depths <1 cm into the brain. Additionally, VP is a more effective photosensitizer than PpIX because it has a higher singlet oxygen yield and is active in the vasculature as well as target tumor cells. However, the hydrophobicity of VP limits effective delivery of the drug to the brain for treatment of GBM.In this context, this thesis aims to re-evaluate the delivery method for VP. VP traditionally requires lipids for delivery as Visudyne. Recent shortages of Visudyne and potential drawbacks of liposomal carriers motivated our development of a carrier-free nanosuspension of VP, termed NanoVP. Previous work has shown that cellular uptake of VP is greater when delivered as NanoVP rather than liposomal VP, resulting in improved cell killing after light activation. This thesis builds on this previous work by (1) evaluating synthesis and storage parameters for NanoVP, (2) determining the pharmacokinetics, biodistribution, and brain bioavailability of NanoVP, and (3) evaluating the potential efficacy of NanoVP as a PDT and a chemotherapy agent, and by supporting development of a zebrafish model of the blood-brain barrier (BBB) for mechanistic studies of improved drug delivery to the brain.Item Immunological and Toxicological Considerations for the Design of Liposomes(MDPI, 2020-01-22) Inglut, Collin T.; Sorrin, Aaron J.; Kuruppu, Thilinie; Vig, Shruti; Cicalo, Julia; Ahmad, Haroon; Huang, Huang-ChiaoLiposomes hold great potential as gene and drug delivery vehicles due to their biocompatibility and modular properties, coupled with the major advantage of attenuating the risk of systemic toxicity from the encapsulated therapeutic agent. Decades of research have been dedicated to studying and optimizing liposomal formulations for a variety of medical applications, ranging from cancer therapeutics to analgesics. Some effort has also been made to elucidate the toxicities and immune responses that these drug formulations may elicit. Notably, intravenously injected liposomes can interact with plasma proteins, leading to opsonization, thereby altering the healthy cells they come into contact with during circulation and removal. Additionally, due to the pharmacokinetics of liposomes in circulation, drugs can end up sequestered in organs of the mononuclear phagocyte system, affecting liver and spleen function. Importantly, liposomal agents can also stimulate or suppress the immune system depending on their physiochemical properties, such as size, lipid composition, pegylation, and surface charge. Despite the surge in the clinical use of liposomal agents since 1995, there are still several drawbacks that limit their range of applications. This review presents a focused analysis of these limitations, with an emphasis on toxicity to healthy tissues and unfavorable immune responses, to shed light on key considerations that should be factored into the design and clinical use of liposomal formulations.Item Exploiting Unique Features of Microneedles to Modulate Immunity(Wiley, 2023-06-28) Edwards, C.; Shah, S. A.; Gebhardt, T.; Jewell, C. M.Microneedle arrays (MNAs) are small patches containing hundreds of short projections that deliver signals directly to dermal layers without causing pain. These technologies are of special interest for immunotherapy and vaccine delivery because they directly target immune cells concentrated in the skin. The targeting abilities of MNAs result in efficient immune responses—often more protective or therapeutic—compared to conventional needle delivery. MNAs also offer logistical benefits, such as self-administration and transportation without refrigeration. Thus, numerous preclinical and clinical studies are exploring these technologies. Here we discuss the unique advantages of MNA, as well as critical challenges – such as manufacturing and sterility issues – the field faces to enable widespread deployment. We explain how MNA design parameters can be exploited for controlled release of vaccines and immunotherapies, and the application to preclinical models of infection, cancer, autoimmunity, and allergies. We also discuss specific strategies to reduce off-target effects compared to conventional vaccine delivery routes, and novel chemical and manufacturing controls that enable cargo stability in MNAs across flexible intervals and temperatures. We then examine clinical research using MNAs. We conclude with drawbacks of MNAs and the implications, and emerging opportunities to exploit MNAs for immune engineering and clinical use.Item Nanoparticle-assisted, image-guided laser interstitialthermal therapy for cancer treatment(Wiley, 2022-06-23) Pang, Sumiao; Kapur, Anshika; Zhou, Keri; Anastasiadis, Pavlos; Ballirano, Nicholas; Kim, Anthony J.; Winkles, Jeffrey A.; Woodworth, Graeme F.; Huang, Huang-ChiaoLaser interstitial thermal therapy (LITT) guided by magnetic resonance imaging (MRI) is a new treatment option for patients with brain and non-central nervous system (non-CNS) tumors. MRI guidance allows for precise placement of optical fiber in the tumor, while MR thermometry provides real-time monitoring and assessment of thermal doses during the procedure. Despite promising clinical results, LITT complications relating to brain tumor procedures, such as hemorrhage, edema, seizures, and thermal injury to nearby healthy tissues, remain a significant concern. To address these complications, nanoparticles offer unique prospects for precise interstitial hyperthermia applications that increase heat transport within the tumor while reducing thermal impacts on neighboring healthy tissues. Furthermore, nanoparticles permit the co-delivery of therapeutic compounds that not only synergize with LITT, but can also improve overall effectiveness and safety. In addition, efficient heat-generating nanoparticles with unique optical properties can enhance LITT treatments through improved real-time imaging and thermal sensing. This review will focus on (1) types of inorganic and organic nanoparticles for LITT; (2) in vitro, in silico, and ex vivo studies that investigate nanoparticles' effect on light–tissue interactions; and (3) the role of nanoparticle formulations in advancing clinically relevant image-guided technologies for LITT.Item The effects of mechanical confinement on cancer cell growth and migration mechanisms(2021) Moriarty, Rebecca; Stroka, Kimberly M; Mili, Stavroula; Bioengineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Cancer is a disease in which cell growth proceeds unchecked and cells accumulate mutations to adopt an invasive and migratory phenotype that promotes metastasis. Once a cancer becomes metastatic, survival rates plummet, and vast tumor heterogony and lesion formation leave current therapeutics and treatments unable to maintain pace. Therefore, there exists a clinical need to gain a more complex understanding of factors that promote and encourage metastasis. Cancer cells are subjected to mechanical forces in vivo that influence their behavior. Mechanical cues are transmitted through the cell from the membrane to the cytoskeleton, and ultimately to the nucleus where gene expression and subsequently protein output can be altered. In this dissertation, we probed the effects of mechanical confinement, a restrictive force present at various stages during the metastatic cascade, on (1) cancer cell growth and cell cycle progression, (2) global mRNA translational and its relationship to cell migration, and (3) mRNA localization mechanisms for use in confined cell migration. We modeled confinement in vitro through fabrication of microfluidic microchannel devices. We show here that mechanical confinement halts sarcoma cell cycle progression and division and leads to an increase in abnormal divisions. We explored the connection between mRNA translation and cell migration and found that global mRNA translation is spatially altered in confinement and that it is necessary for confined cell migration. We explored this idea further, investigating a subset of mRNAs that are known to influence cell migration in unconfined spaces and show that their regulation in confinement is cell type dependent, but that it primarily relies on cell mechanoactivity. Together, this work contributes a detailed understanding of key cell behaviors that are altered in confined environments and emphasizes the importance of studying mechanical cues that cells experience in vivo, in the context of understanding and treating cancer progression and metastasis.Item Mechanical Adaptability of Ovarian Cancer Tumor Spheroids(2021) Conrad, Christina Barber; Scarcelli, Giuliano; Bioengineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)A major obstacle in ovarian cancer treatment is the onset of ascites, an abnormal build-up of fluid in the peritoneal cavity. Using in vitro perfusion models, ascitic flow has been shown to drive epithelial-mesenchymal-transition (EMT) biomarker expression, promote epidermal growth factor receptor (EGFR) downstream signaling, and upregulate chemoresistance. Given the close ties between cell mechanics and behaviors, it is of interest to establish if mechanotransduction serves a role in cell signaling dysfunction. Here, we identified the mechanical behavior of tumor spheroids subjected to flow using Brillouin confocal microscopy, a non-contact optical method based on the interaction between incident light and microscopic mechanical waves within matter. We validated this technique by establishing a relationship with the traditionally derived Young’s modulus measured using atomic force microscopy and a parallel-plate compression device. Following characterization, we used Brillouin confocal microscopy to map mechanical properties of tumor spheroids embedded in a microfluidic chip and found that continuous flow for 7 days caused a decreased Brillouin shift (i.e., stiffness) compared to tumors in a static condition. Another physical phenomenon related to ascites is dysregulated osmolality. Maintaining cell water homeostasis is driven by the transport of water to balance solute concentration and can have direct consequences on mechanics and biochemical signaling in cells. Recently, it was demonstrated in single cells that cell volume correlated with mechanical properties; but the effects in tumor spheroids which exhibit multi-cellular interfaces has remained unclear. Here, we derived relationships between osmolality and nuclear volume, tumor cell density, and Young’s modulus, and found the correlations in spheroids resembled single cell relationships previously described in literature. Additionally, we looked at the impact of osmotic shocks on E-cadherin junctions and found aggregates formed with a unique timescale compared to morphology. Lastly, we observed reversibility of the mechanical, morphological, and molecular properties which showed the tumor’s dynamic ability to respond to physical cues. Altogether, this work demonstrated how flow and osmosis associated with ovarian cancer ascites can trigger phenotype transformations. These findings warrant future investigations into how the regulation of mechanotransduction pathways can be harnessed to prevent chemoresistance and signaling dysfunction.Item Bio-Derived Microscale Containers for Disease Treatment and Diagnostics(2017) Liu, James; Raghavan, Srinivasa R; Chemical Engineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Micro-erythrosomes (mERs) are microscale containers (3 to 5 µm in diameter) derived from red blood cells (RBCs, also called erythrocytes). They are prepared by removing hemoglobin from RBCs and resuspending the empty structures in buffer. In this work, we focus on adding new functionalities to mERs, with both therapeutics and diagnostics in mind. In our main study, we demonstrate the use of mERs as “Killer Cells” to attack cancer. mERs are loaded with the enzyme glucose oxidase (GOx) and then incubated in vitro with a strain of head and neck cancer cells (15B). In the presence of glucose from external media, the Killer Cells generate hydrogen peroxide (H2O2). H2O2 is a reactive oxygen species (ROS) which induces the cancer cells to undergo apoptosis (programmed cell death). We find a reduction in 15B cell viability of over 80%. In ancillary studies, we explore strategies for the long-term retention of solutes in mERS. Specifically, the cationic biopolymer chitosan is adsorbed to the surfaces of mERs, and the anionic biopolymer alginate is encapsulated in their cores. Both strategies are able to extend the diffusion time for loaded solutes. Additionally, we have attempted to adapt mERs for use as MRI contrast agents by incorporating lipids containing gadolinium into the membrane. These studies lay the foundation for many mER applications and demonstrate their versatility.Item Biodegradable Prussian blue nanoparticles for photothermal immunotherapy of advanced cancers(2015) Cano-Mejia, Juliana; Fernandes, Rohan; Bioengineering; Digital Repository at the University of Maryland; University of Maryland (College Park, Md.)Multifunctional nanoparticles represent a class of materials with diverse therapy and imaging properties that can be exploited for the treatment of cancers that have significantly progressed or advanced, which are associated with a poor patient prognosis. Here, we describe the use of biodegradable Prussian blue nanoparticles (PBNPs) in combination with anti-CTLA-4 checkpoint blockade immunotherapy for the treatment of advanced cancers. Our nanoparticle synthesis scheme yields PBNPs that possess pH-dependent intratumoral stability and photothermal therapy (PTT) properties, and degrade under mildly alkaline conditions mimicking the blood and lymph. Studies using PBNPs for PTT in a mouse model of neuroblastoma, a hard-to-treat cancer, demonstrate that PTT causes rapid reduction of tumor burden and growth rates, but results in incomplete responses to therapy and tumor relapse. Studies to elucidate the underlying immunological responses demonstrate that PTT causes increased tumor infiltration of lymphocytes and T cells and a systemic activation of T cells against re-exposed tumor cells in a subset of treated mice. PBNP-based PTT in combination with anti-CTLA-4 immunotherapy results in complete tumor regression and long-term survival in 55.5% of neuroblastoma tumor-bearing mice compared to only 12.5% survival in mice treated with anti-CTLA-4 alone and 0% survival both in mice treated with PTT alone, or remaining untreated. Further, all of the combination therapy-treated mice exhibit protection against tumor rechallenge indicating the development of antitumor immunity as a consequence of therapy. Our studies indicate the immense potential of our combination photothermal immunotherapy in improving the prognosis and outlook for patients with advanced cancers.