Molecular, Cellular, and Tissue Engineering Commons^™

Proteoglycan Mimic Of The Glycocalyx To Treat Endothelial Dysfunction, Victoria Messerschmidt, Alyssa Panitch, James R. Wodicka

The Summer Undergraduate Research Fellowship (SURF) Symposium

Patients with kidney failure usually undergo hemodialysis, a process by which toxins produced by the body are filtered from the blood, in order to survive. The preferred form for vascular access is called an arteriovenousfistula (AVF), a surgically created connection between an artery and vein that is utilized to undergo dialysis. However, AVFs have a failure rate of 50-60%. One of the contributions to AVF failure is endothelial cell dysfunction and loss of glycocalyx, which allows neutrophils and other native cells into the media of the vessel, which causes an inflammatory response. Our lab addresses endothelial dysfunction by mimicking the …

Buckling-Driven Force Generation Of Cell Cortex, Pranith Lomada, Wonyeong Jung, Taeyoon Kim

The Summer Undergraduate Research Fellowship (SURF) Symposium

Actomyosin cortex, a thin network underlying cell membrane, is known to generate a large portion of tensile forces required for various cellular processes. Recently, theoretical studies predicted that buckling of actin filaments breaks symmetry between tensile and compressive forces developed by myosin motors, resulting in tensile stress at a network level. However, the significance of the filament buckling of the cortex has yet to be demonstrated either computationally or experimentally. Here, buckling-dependent stress generation of the cortex-like actomyosin network was investigated using an agent-based computational model consisting of actin filaments, actin cross-linking proteins (ACPs), and molecular motors. First, a wide …

Harnessing Notch Signaling For Biomaterial Scaffold-Based Bone Regeneration, Helena P. Lysandrou, Chunhui Jiang, Naagarajan Narayanan, Shihuan Kuang, Meng Deng

The Summer Undergraduate Research Fellowship (SURF) Symposium

Bone fracture has recently become prevalent, especially with an increasingly aging population. Current bone grafts procedures, including autografts and allografts, are hindered by multiple factors, such as limited supplies and inconsistent bone healing. Scaffold-based bone tissue engineering emerges as a prospective strategy to aid in bone regeneration through delivery of growth factors such as bone morphogenic proteins (BMPs). However, the use of BMPs suffers from several drawbacks such as protein instability and immunogenicity. Therefore, there exists a great need for the development of novel therapies to promote bone healing. Notch signaling, a pathway critical for cell-fate determination has been shown …

Breast Cancer/Stromal Cells Coculture On Polyelectrolyte Films Emulates Tumor Stages And Mirna Profiles Of Clinical Samples, Amita Daverey, Karleen M. Brown, Srivatsan Kidambi

Department of Chemical and Biomolecular Engineering: Faculty Publications

In this study, we demonstrate a method for controlling breast cancer cells adhesion on polyelectrolyte multilayer (PEM) films without the aid of adhesive proteins/ ligands to study the role of tumor and stromal cell interaction on cancer biology. Numerous studies have explored engineering coculture of tumor and stromal cells predominantly using transwell coculture of stromal cells cultured onto coverslips that were subsequently added to tumor cell cultures. However, these systems imposed an artificial boundary that precluded cell−cell interactions. To our knowledge, this is the first demonstration of patterned coculture of tumor cells and stromal cells that captures the temporal changes …

Monitoring The Progression Of Spontaneous Articular Cartilage Healing With Infrared Spectroscopy, Megan P. O'Brien, Madhuri Penmatsa, Uday Palukuru, Paul West, Xu Yang, Mathias P. G. Bostrom, Theresa Freeman, Nancy Pleshko

Publications and Research

Objective. Evaluation of early compositional changes in healing articular cartilage is critical for understanding tissue repair and for therapeutic decision-making. Fourier transform infrared imaging spectroscopy (FT-IRIS) can be used to assess the molecular composition of harvested repair tissue. Furthermore, use of an infrared fiber-optic probe (IFOP) has the potential for translation to a clinical setting to provide molecular information in situ. In the current study, we determined the feasibility of IFOP assessment of cartilage repair tissue in a rabbit model, and assessed correlations with gold-standard histology.

Design. Bilateral osteochondral defects were generated in mature white New Zealand rabbits, and …

Capillary Electrophoresis For Analysis Of Aβ1-42 Adsorption And Photo-Crosslinking, Jennifer Lynn Kurtz

Graduate Theses and Dissertations

The accumulation of amyloid-beta (Aβ) oligomers is believed to be the driving force behind Alzheimer’s disease (AD) pathogenesis. Due to the metastable nature of Aβ oligomers, the knowledge of Aβ aggregation and accumulation is not well understood. Here, we use capillary electrophoresis (CE) and photo-induced crosslinking of unmodified proteins (PICUP) to learn about the aggregation of Aβ.

First, we explore the effect of capillary coating on Aβ1-42 protein loss using CE. The dynamic coatings tested were PHEA and 50 kDa, 2000 kDa, 5000 kDa, and 8000 kDa PEO. The covalent coating tested was PVA. The results indicated that 2000 kDa …

Characterization Of Human Muscle Extracellular Matrix, Lauren Klaire Wilson

Graduate Theses and Dissertations

The performance of extracellular matrix (ECM) biological scaffolds for the treatment of volumetric muscle loss (VML) has shown promising results with regenerating native muscle in animal models and human patients. However, the limitations of these scaffolds include non-specific characteristics based on the original parameters of the muscle that is lost and this is why our group chose to characterize human skeletal ECM. By understanding the characteristics of the native human skeletal ECM, more desired queues for the biological scaffolds being used to treat VML can be provided. Upper limb and lower limb skeletal muscles were commercially obtained, decellularized using common …

Design And Development Of Two Component Hydrogel Ejector For Three-Dimensional Cell Growth, Thomas Dunkle, Jessica Deschamps, Connie Dam

Honors Scholar Theses

Hydrogels are useful in wound healing, drug delivery, and tissue engineering applications, but the available methods of injecting them quickly and noninvasively are limited. The medical industry does not yet have access to an all-purpose device that can quickly synthesize hydrogels of different shapes and sizes. Many synthesis procedures that have been developed result in the formation of amorphous hydrogels. While generally useful, amorphous hydrogels exhibit limited capability in tissue engineering applications, especially due to their viscous properties. This endeavor aims to modulate the appropriate gelation parameters, optimize the injection process, and create a prototype that allows for the extrusion …

Finite Element Analysis Of The Application Of Ultrasound-Generated Acoustic Radiation Force To Biomaterials, Nicole J. Piscopo

Honors Scholar Theses

While most bone fractures can heal simply by being stabilized, others can take a longer time to rejoin or they could fail to merge back together completely. Numerous studies have shown the positive effects that ultrasonic therapy have had on delayed-union and non-union bone fracture repair but little is known as to what specific biological mechanisms are at play. Ultrasound may be a valuable tool for bone tissue regeneration at these fracture sites using a tissue engineering approach, however, more must be understood about its impact on stimulating tissues to heal before this can be a reality. For that reason, …

Selection Methods For Genetically-Modified T Cells: In Support Of Translational Therapy, David Rushworth

Dissertations and Theses (Open Access)

T cells are blood cells which organize the immune system of the host. These cells are necessary for the host to respond appropriately to threats from foreign organisms and cancerous growth. However, in the case of certain infections and cancer, T cells are unable to respond appropriately to a threat and establish immunity. This leads to disease when the infection or cancer is not sufficiently eliminated. On the other hand, T cells can lack tolerance for healthy tissue and perceive healthy tissue as infected. The ensuing over-reactive immune response also leads to disease. A delicate balance must exist between immunity …

Mitochondrial Dysfunction And Loss Of Glutamate Uptake In Primary Astrocytes Exposed To Titanium Dioxide Nanoparticles, Christina L. Wilson

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

The proper function of astrocytes is critical for brain health as they are the most abundant cells in the brain which monitor ion homeostasis, recycle neurotransmitters and respond to tissue damage therefore disruption in astrocyte function can result in overall detrimental effects and has been linked with neurodegenerative diseases. Titanium Dioxide (TiO₂) nanoparticles are currently the second most produced engineered nanomaterial in the world with vast usage in consumer products leading to recurrent human exposure. Animal studies indicate significant nanoparticle accumulation in the brain while cellular toxicity studies demonstrate negative effects on neuronal cell viability and function. However, …

Man Made Organs: Technology Made It Possible But Can The Fda Keep Up?, Amanda Chatman

North Carolina Central University Science & Intellectual Property Law Review

No abstract provided.

Altered Cd161bright Cd8+ Mucosal Associated Invariant T (Mait)-Like Cell Dynamics And Increased Differentiation States Among Juvenile Type 1 Diabetics., Robert Z. Harms, Kristina M. Lorenzo, Kevin P. Corley, Monina S. Cabrera, Nora Sarvetnick

Journal Articles: Regenerative Medicine

Type 1A diabetes (T1D) is believed to be caused by immune-mediated destruction of β-cells, but the immunological basis for T1D remains controversial. Microbial diversity promotes the maturation and activation of certain immune subsets, including CD161bright CD8+ mucosal associated invariant T (MAIT) cells, and alterations in gut mucosal responses have been reported in type 1 diabetics (T1Ds). We analyzed T cell populations in peripheral blood leukocytes from juvenile T1Ds and healthy controls. We found that proportion and absolute number of MAIT cells were similar between T1Ds and controls. Furthermore, while MAIT cell proportions increased with age among healthy controls, this trend …

Multiplexed Loop-Mediated Isothermal Amplification Of The 16s Rrna Gene For The Diagnosis Of Neonatal Sepsis In Resource-Limited Environments, Griffin T. Sonaty

Inquiry: The University of Arkansas Undergraduate Research Journal

Sepsis, or dysregulated inflammation caused by bacterial infection, places a disproportionately high burden on newborns in developing countries. This is due in part to a lack of diagnostic tools suitable for sustainable use in resource-limited nurseries. One potential vehicle for a new diagnostic assay is loop-mediated isothermal amplification (LAMP), a high-yield DNA amplification method. LAMP has previously been used to detect genes from single species of bacteria in blood serum samples to aid in sepsis diagnosis. LAMP could be adapted to detect a broad set of bacteria, while retaining a degree of specificity that allows clinicians to begin directed antimicrobial …

Systematic Study Of The Biological Effects Of Nitric Oxide (No) Using Innovative No Measurement And Delivery Systems, Weilue He

Dissertations, Master's Theses and Master's Reports

Nitric oxide (NO) is recognized as the most important small signaling molecule in the human body. An imbalance of NO is closely associated with many serious diseases such as neurological disorders, cardiovascular diseases, chronic inflammations and cancers. Herein two chemiluminescence-based devices (a real-time NO measurement device and a controllable NO delivery device) were developed to facilitate the NO quantitative study and obtain information for NO related drug design.

The first device used for real-time measuring NO(g) flux from living cells was developed and validated. The principle was to use a two-chamber design, with a cell culture chamber and a gaseous …

Engineering Approaches For Suppressing Deleterious Host Responses To Medical Implants, Connor Mccarthy

Dissertations, Master's Theses and Master's Reports

Small diameter (< 6 mm) vascular grafts suffer from serious deleterious effects not encountered with their larger diameter relatives, leading to premature graft failure through restenosis. Platelet activation, inflammation, and smooth muscle cell proliferation are leading contributors to thrombosis and neointimal hyperplasia, both contributors to the progression of restenosis. It may be possible to suppress negative biological responses to vascular implants through the modification of surface properties and incorporation of drug release into blood contacting materials. In this work, bioengineering approaches are presented to improve the biocompatibility of small diameter vascular grafts.

We demonstrate a novel engineering approach for incorporating natural, decollagenized elastin matrices into PEU 1074A reinforced vascular grafts through spray-coating and electrospinning processes in a manner that retains elastin’s excellent blood contacting properties. A vascular construct with excellent mechanical and surgical handling properties demonstrating the suppression of neointimal hyperplasia is presented after 21 days in vivo.

Nitric oxide (NO) has been investigated over the past several decades due to its platelet, inflammation, and smooth muscle cell suppressing effects; and if appropriately delivered, could positively mediate the contributors to restenosis. Here, we characterize a novel macrocyclic NO …

The Effect Of Cholesterol On The Osteoblast Responsiveness To Hydrodynamic Pressure Stimulation, Kristen Lough

Theses and Dissertations--Biomedical Engineering

Hypercholesterolemia is a risk factor for osteoporosis but the underlying mechanism is unknown. Previous evidence suggests that osteoporosis results from an impaired regulation of osteoblasts by fluid pressure fluctuations in the bone matrix. Recently, our laboratory showed that enhanced cholesterol in the cell membrane, due to hypercholesterolemia, alters leukocyte mechanosensitivity. We predict a similar link between osteoblasts and hypercholesterolemia leading to osteoporosis. Specifically, we hypothesize that extracellular cholesterol modifies the osteoblast sensitivity to pressure. MC3T3-E1 cells were exposed to hydrodynamic pressures regimes (mean=40mmHg, amplitude=0-20mmHg, frequency=1Hz) for 1-12 hours. To assess the impact of membrane cholesterol enrichment, cells were pre-treated with …

Up Regulation Of Heat Shock Protein 70b (Hsp70b) And Ssa1 In Chlamydomonas Reinhardtii Via Hsp70a-Rbcs2 And Psad Promoter, B. Kirtley Amos

Theses and Dissertations--Biosystems and Agricultural Engineering

Fabrication of effective algae cultivation systems adjacent to coal-fired power plants to fixate waste CO₂ would represent a sizable step towards achieving a carbon neutral energy cycle. However, emission gas would elevate the algal cultivation system temperature and decreases its pH without expensive preprocessing. Increased temperature and acidity constitutes a profound stress on the algae. Although stressed algae produce heat shock proteins (HSPs) that promote protein folding and protect against stress, the ordinary biological response is insufficient to protect against coal flue gas. Experimental upregulation of HSPs could make algae respond to the stress caused by high temperatures and …

Fluorescent Biosensors To Measure Endothelial Cell Responses To Fluid Shear Stress, Natalie Noll

Undergraduate Research Posters

The response of endothelial cells, innermost layer of blood vessels, to blood flow is thought to be critical in the initiation and progression of atherosclerosis. Atherosclerosis in the human body is non-random and is highly correlated to vessel sites which experience oscillatory and reversing blood flow. Endothelial cells (ECs), the inner most cell layer of blood vessels are highly responsive to the drag force from blood flow, known as shear stress. To study endothelial cell responses to shear stress we used a parallel plate flow chamber in which we exposed endothelial cells to defined fluid shear stress. Using fluorescence resonance …

Primary Cilia Mechanotransduction And Microtubule Stability In Mechanically Stretched Lung Adenocarcinoma Cells, Monika Rassi Radhika

Theses and Dissertations

The objective of this study is to investigate the role of microtubule based organelle, the primary cilia in lung adenocarcinoma by i) Quantifying the presence of primary cilia in several Non Small Cell Lung Cancer (NSCLC) cell lines in response to mechanical stimuli, ii) Attempting to determine the role of primary cilia in cell migration, iii) Investigating the effects of Paclitaxel(Taxol) resistance in lung cancer cells, iv) Analyzing the response of lung cancer cells to Smoothened Inhibitors and v) Determining the effects of Transforming Growth Factor Beta-1(TGF-β1) induced Epithelial to Mesenchymal Transition(EMT) in lung cancer cells. To ascertain the effects …

Ex Vivo Dna Cloning, Adam B. Fisher

Theses and Dissertations

Genetic engineering of microbes has developed rapidly along with our ability to synthesize DNA de novo. Yet, even with decreasing DNA synthesis costs there remains a need for inexpensive, rapid and reliable methods for assembling synthetic DNA into larger constructs or combinatorial libraries. While technological advances have resulted in powerful techniques for in vitro and in vivo assembly of DNA, each suffers inherent disadvantages. Here, an ex vivo DNA cloning suite using crude cellular lysates derived from E. coli is demonstrated to amplify and assemble DNA containing small sequence homologies. Further, the advantages of an ex vivo approach are …

Thermosensitive Gel Containing Cellulose Acetate Phthalate-Efavirenz Combination Nanoparticles For Prevention Of Hiv-1 Infection, Abhijit A. Date, Annemarie Shibata, Emily Mcmullen, Krista La Bruzzo, Patrick Bruck, Michael Belshan, You Zhou, Christopher J. Destache

Nebraska Center for Biotechnology: Faculty and Staff Publications

The objective of this investigation was to develop and evaluate a nano-microbicide containing a combination of cellulose acetate phthalate (HIV-1 entry inhibitor) and efavirenz (anti-HIV agent) for HIV prophylaxis. Cellulose acetate phthalate-efavirenz combination nanoparticles (CAP-EFV-NPs) were fabricated by the nanoprecipitation method and were characterized for particle size, zeta potential and encapsulation efficiency of efavirenz. CAP-EFV-NPs were incorporated into a thermosensitive gel (CAP-EFV-NP-Gel). CAP-EFV-NPs, CAP-EFV-NP-Gel and efavirenz solution were evaluated for cytotoxicity to HeLa cells and for in vitro short-term (1-day) and long-term (3-day) prophylaxis against HIV-1 infection in TZM-bl cells. CAP-EFV-NPs had size < 100 nm, negative surface charge and encapsulation efficiency of efavirenz was > 98%. CAP-EFV-NPs and CAP-EFV-NP-Gel were significantly less …

Automating The Process Of Fabricating Uniform-Sized Cell Spheroids For Three-Dimensional Bioprinting, Ganesh Sosale

Theses and Dissertations

Although researchers have been able to print small, simple, and avascular tissues, they have been unsuccessful in creating large, complex and vascularized organs. Printing large and complex three-dimensional tissues or organs involves utilizing a large quantity of cellular spheroids and layer-by-layer addition of spheroids. In this study, an in-house cell spheroid fabrication system was developed to produce cell spheroids with human liver cells (hepG2), human endothelial cells (hEC), human neural stem cells (hNSC), and induced pluripotent stem cells (iPSC). It offers the ability of fabricating uniform-sized spheroids repeatedly, which is essential when large and complex structures need to be produced. …

Long-Acting Antituberculous Therapeutic Nanoparticles Target Macrophage Endosomes, Benson J. Edagwa, Dongwei Guo, Pavan Puligujja, Han Chen, Joellyn Mcmillan, Xinming Liu, Howard Gendelman, Prabagaran Narayanasamy

Nebraska Center for Biotechnology: Faculty and Staff Publications

Eradication of Mycobacterium tuberculosis (MTB) infection requires daily administration of combinations of rifampin (RIF), isoniazid [isonicotinylhydrazine (INH)], pyrazinamide, and ethambutol, among other drug therapies. To facilitate and optimize MTB therapeutic selections, a mononuclear phagocyte (MP; monocyte, macrophage, and dendritic cell)-targeted drug delivery strategy was developed. Long-acting nanoformulations of RIF and an INH derivative, pentenyl- INH (INHP), were prepared, and their physicochemical properties were evaluated. This included the evaluation of MP particle uptake and retention, cell viability, and antimicrobial efficacy. Drug levels reached 6 μg/106 cells in human monocyte-derived macrophages (MDMs) for nanoparticle treatments compared with 0.1 μg/106 cells for native …

Development And Characterization Of An Autologous Whole Cell Breast Cancer Vaccine, Samantha Leigh Kurtz

Graduate Theses and Dissertations

Approximately 40,000 women will die from breast cancer in the United States in 2014. About 90% of these deaths will be due to metastases, rather than the primary tumor and majority of metastases are due to the recurrence and progression of non-metastatic disease. Current adjuvant treatments, such as chemotherapy and radiation, have severe side effects and may result in overtreatment and drug resistance.

Since greater than 90% of patients are diagnosed between stages I-III and have minimal residual disease after treatment, there is an opportunity to treat patients with an autologous breast cancer vaccine. Autologous vaccines under development have a …

Low Molecular Weight Glucosamine/L-Lactide Copolymers As Potential Carriers For The Development Of A Sustained Rifampicin Release System: Mycobacterium Smegmatis As A Tuberculosis Model, Jorge Ragusa

Department of Chemical and Biomolecular Engineering: Dissertations, Theses, and Student Research

Tuberculosis, a highly contagious disease, ranks as the second leading cause of death from an infectious disease, and remains a major global health problem. In 2013, 9 million new cases were diagnosed and 1.5 million people died worldwide from tuberculosis. This dissertation aims at developing a new, ultrafine particle-based efficient antibiotic delivery system for the treatment of tuberculosis. The carrier material to make the rifampicin (RIF)-loaded particles is a low molecular weight star-shaped polymer produced from glucosamine (molecular core building unit) and L-lactide (GluN-LLA). Stable particles with a very high 50% drug loading capacity were made via electrohydrodynamic atomization. Prolonged …

Characterization Of Bone Material Properties And Microstructure In Osteogenesis Imperfecta/Brittle Bone Disease, John Robert Jameson

Dissertations (1934 -)

Osteogenesis imperfecta (OI) is a genetic disorder primarily associated with mutations to type I collagen and resulting in mild to severe bone fragility. To date, there is very little data quantifying OI cortical bone mechanics. The purpose of this dissertation was to investigate bone microstructure, mineralization, and mechanical properties in adolescents with OI. Characterization studies were performed on small osteotomy specimens obtained from the extremities during routine corrective surgeries. Nanoindentation was used to examine the longitudinal elastic modulus and hardness at the material level for mild OI type I vs. severe OI type III. Both modulus and hardness were significantly …

Virus-Host Mucosal Interactions During Early Siv Rectal Transmission, Wuxun Lu, Fangrui Ma, Alexander Churbanov, Yanmin Wan, Yue Li, Guobin Kang, Zhe Yuan, Dong Wang, Chi Zhang, Jianqing Xu, Mark Lewis, Qingsheng Li

Nebraska Center for Biotechnology: Faculty and Staff Publications

To deepen our understanding of early rectal transmission of HIV-1, we studied virus-host interactions in the rectal mucosa using simian immunodeficiency virus (SIV)-Indian rhesus macaque model and mRNA deep sequencing. We found that rectal mucosa actively responded to SIV as early as 3 days post-rectal inoculation (dpi) and mobilized more robust responses at 6 and 10 dpi. Our results suggests that the failure of the host to contain virus replication at the portal of entry is attributable to both a high-level expression of lymphocyte chemoattractant, proinflammatory and immune activation genes, which can recruit and activate viral susceptible target cells into …

Biological Implications Of Satellite Cells For Scaffold-Based Muscle Regenerative Engineering, Maggie R. Del Ponte, Charter Chain, Meng Deng Dr., Feng Yue Dr., Shihuan Kuang Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Satellite cells are anatomically localized along the surface of muscle fibers and have been regarded as a population of muscle-specific progenitors that are responsible for muscle regeneration. In response to muscle injuries, satellite cells are activated to enter the cell cycle, then proliferate and differentiate into mature muscle cells to regenerate damaged myofibers. Unfortunately, this natural repair mechanism is interrupted in conditions such as muscle degenerative diseases or volumetric muscle loss. The function of stem cells is regulated by signals from their local microenvironment which is called the stem cell niche. Current satellite cell-based strategies such as direct cell transplantation …

Using Collagen Binding Poly(N-Isopropylacrylamide) Nanoparticles To Prevent Intravascular Platelet Adhesion And Activation, Anna E. Searle, Alyssa Panitch, James Mcmasters

The Summer Undergraduate Research Fellowship (SURF) Symposium

Balloon angioplasty, the most prevalent non-surgical treatment for Atherosclerosis, damages the endothelial layer of the artery, baring an underlying collagenous layer, which causes platelet adhesion and activation and eventual thrombosis and intimal hyperplasia. Previous work in our lab has used a collagen-binding peptidoglycan, dermatan-sulfate-SILY (DS-SILY), that has been shown to bind to type I collagen and prevent platelet adhesion and activation. Our goal is to fabricate nanoparticle-SILY by cross-linking SILY to a poly(N-isopropylacrylamide) (NIPAm) nanoparticle instead of a DS backbone, while retaining the SILY’s high collagen binding affinity and platelet inhibition capacity observed in DS-SILY. Using a biotin-streptavidin assay, we …