Molecular, Cellular, and Tissue Engineering Commons^™

Manufacturing Silicone In-House For The Creation Of Customized Neurovascular Blood Vessel Mimics, Jacob Wilbert Perisho

Master's Theses

The Tissue Engineering Lab at California Polytechnic State University San Luis Obispo focuses on creating tissue-engineered Blood Vessel Mimics (BVMs) designed for the preclinical testing of neurovascular devices. These BVMs are composed of silicone models, representing anatomically accurate neurovasculatures, that are sodded with vascular cell types and then cultivated in bioreactors (which maintain physiologic conditions). These silicone models are currently sourced externally from industry partners, so the primary goal of this thesis was to develop the means and methods for the Tissue Engineering Lab to manufacture silicone models in-house.

The first aim of this thesis was to develop and explore …

Evaluating Tissue Morphology In The Context Of Varied Initial Fabrication Conditions, Cassidy Caffin

Biomedical Engineering Undergraduate Honors Theses

Cardiovascular diseases have been the leading cause of death for years. This includes myocardial infarctions (MI) where blood flow to the myocardium is restricted. This causes damage to cardiac muscle due to insufficient oxygen. There are multiple ways to treat patients following an MI with the most common involving assorted medication. However, there are limited medications that can be used for treating patients following MIs, and the FDA’s decreasing approval rate for new cardiac drugs will not dramatically improve the range of options. The lead-up to drug candidate rejection by the FDA can involve drugs exhibiting promising preliminary research that …

Utilizing Spatial Transcriptomics To Compare Gene Expression In Volumetric Muscle Loss Injury Recovery, Colton Gattis

Biomedical Engineering Undergraduate Honors Theses

Volumetric Muscle Loss (VML) injuries are known to disrupt the normal regenerative process via fibrosis leading to an extensive permanent loss of muscle function. The specific causation of this disruption remains to be defined; however, with new developments in transcriptomics, genetic trends can be identified across regions of tissue over time. This study follows VML injuries within the tibialis anterior of a mouse model for fifteen days after initial injury to attempt to identify expected transitions in healing. Genetic presence began to become more diversified as recovery progressed from four to fifteen days post injury with spatial clusters becoming globalized …

Investigating The Presence Of Patented In Vitro Models For Cancer-Nerve Crosstalk Methods, Christoff Hauptmann

Biomedical Engineering Undergraduate Honors Theses

The purpose of this research project is to investigate the presence of patented in vitro models for perineural invasion (PNI) and tumor innervation, the two most prominent modes of cancer-nerve crosstalk that play an active role in cancer initiation and progression. PNI occurs through a positive feedback loop in which cancer cells invade passive nerves to metastasize. Tumor innervation is the process where tumor cells attract nearby nerves to the tumor microenvironment (TME) for tumor growth and metastasis. These crosstalk paths have been established for many types of cancer and result in poor patient prognosis. Recently, in vitro models have …

Evaluation Of The Efficiency Of Muscle-Specific Promoters To Express Non-Endogenous Proteins In Skeletal Muscle, Gabrielle Bulliard, Made Harumi Padmaswari, Christopher E. Nelson

Biomedical Engineering Undergraduate Honors Theses

Gene therapies are emerging as powerful tools for treating genetic diseases and cancers, offering the potential for a permanent cure. Hemophilia B, affecting approximately 6,000 men in the U.S., results from a deficiency in coagulation factor IX protein (FIX), which is crucial for blood clotting. A substantial portion of patients, over 40%, suffer from severe hemophilia B, experiencing spontaneous, prolonged bleeding. Current prophylactic treatments involve frequent coagulation factor infusions, yet a curative approach would alleviate this burden. Gene editing technologies like CRISPR-Cas systems show promise for correcting genetic mutations, but the diverse nature of factor IX gene (F9) …

Environment And Response Of 3d-Encapsulated Mesenchymal Stem Cells To Mechanical Loading, Augustus Greenwood

McKelvey School of Engineering Graduate Student Theses & Dissertations

This thesis explores the micromechanical environment induced when cyclically compressing hydrogels via finite element modeling and experimentally on the impact of loading on mesenchymal stem cells (MSCs) when encapsulated withing 3D hydrogel matrices. Degenerative joint diseases, characterized by cartilage degradation, present significant challenges due to cartilage's limited self-repair capacity. Innovative approaches, including stem cell-based therapies and engineered biomaterials, have emerged as promising strategies for cartilage repair and regeneration. This work specifically investigates the calibration of a bioreactor, the uniformity of load response across the hydrogel constructs via finite element modeling (FEM), and the stress response of MSCs subjected to various …

Transcriptomic Profiling Of Engineered Human Gene Integration In The Mouse Genome Following In Vitro Gene Editing, Ethan Potts, Made Harumi Padmaswari, Christopher Nelson

Biomedical Engineering Undergraduate Honors Theses

Gene replacement is a promising method of therapy for genetic diseases. However, safety and efficacy are areas that need more research. This experiment aims to use RNA sequencing and bioinformatic techniques to provide answers to these questions and provide direction to future studies to develop a gene replacement therapeutic. C2C12 mouse myoblast cells were transfected with a vector containing a CRISPR-Cas9 system and the Human Factor IX (hF9) gene in order to hijack target genes and integrate the hF9 gene. The two target genes, myoglobin (Mb) and creatine kinase (Ckm), were chosen for their high rate of expression and low …

The Determination Of Macrophage Localization In Muscle Injuries Using Spatial Transcriptomics, Julliana Renales

Biomedical Engineering Undergraduate Honors Theses

The repair of traumatic muscle injury is often a long process which can in many cases be insufficient and incomplete. In such cases, scar tissue may form, leading to high risk of re-injury and the prevention of muscle regeneration. An important part of decreasing this risk is gaining a better understanding of the cellular complexities of injury repair. More specifically, macrophage cells are an important piece in the regulation of inflammation and repair. In this project, computational analysis spatial transcriptomic data was performed to examine mouse muscle injury and its development over time. This analysis was used to examine the …

Light-Induced Phase Separation Purification For Monoclonal Antibodies, Xuyang Chen

All Theses

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Acoustofluidic Delivery Of Biomolecules To Cells: A Novel Approach For Preparing Car-T Cells., Madison C. Colebank

Electronic Theses and Dissertations

The continuous pursuit of effective methods for gene transfection in primary human T cells is crucial for advancing cell-based therapies. Viral vectors, currently used in cell-based therapies, involve a lengthy and costly process. This thesis explores the efficacy of coupling acoustofluidic and sonoporation techniques as an alternative non-viral gene transfection approach with primary T cells. Sonoporation, in conjunction with microbubbles, has been demonstrated to induce cavitation, resulting in the formation of pores in the cell membrane through which molecules can enter. Using flow cytometry, we compared the loading efficiency of primary T cells with that of Jurkat T cells to …

Investigating Endothelial Damage During Ischemic Stroke Treatment Using In Vitro And Computational Models, Zackary Lorton

Theses and Dissertations

Large vessel occlusion during acute ischemic strokes requires mechanical thrombectomy (MT) procedures using stent retrievers (SR). However, complete clot removal typically takes several attempts, which can amplify endothelial cell injury (EI). This project aims to characterize the extent of EI during MT using an in vitro vascular platform and a finite-element model (FEM). Impact of SR diameter and characterization of SR mechanical forces are assessed and correlated with human umbilical vein endothelial cell (HUVEC) response. HUVECs were seeded on fibronectin (4 µg/cm²) coated true-scale PDMS arterial phantoms with 2.5 mm luminal diameter. Test groups (n=6) either …

Novel Nucleus Pulposus Biomaterial Development And Low Field Mri Assessment For Intervertebral Disc Degeneration, Mario Krussig

All Dissertations

Intervertebral disc degeneration (IVDD) is a prominent pathology in the modern world that causes debilitating pain for many patients. The onset of IVDD occurs in the nucleus pulposus (NP). NP biomaterials will play a vital role in mitigating the progression of IVDD. Within this work, we sought to synthesize a solubilized extracellular matrix (ECM)-based NP biomaterial. Utilizing pepsin or urea extraction, bovine NP ECM was successfully solubilized (SBNPs). SBNP formulations were characterized biochemically, evaluated for cytotoxicity, and down-selected for front-running formulations. Leading candidate SBNPs were incorporated into an alginate bead biomaterial model to determine the potential bioactivity with human adipose-derived …

Low Impedance, Durable, Self-Adhesive Hydrogel Epidermal Electrodes For Electrophysiology Recording, Naiyan Wu

McKelvey School of Engineering Graduate Student Theses & Dissertations

Traditional electrodes used for electrophysiology recording, characterized by their hard, dry, and inanimate nature, are fundamentally mismatched with the soft, moist, and bioactive characteristics of biological tissues, leading to suboptimal skin-electrode interfaces. Hydrogel materials, mirroring the high water content and biocompatibility of biological tissues, emerge as promising candidates for epidermal electronic materials due to their adjustable physicochemical properties. However, challenges such as inadequate electrical conductivity, elevated skin impedance, unreliable adhesion in moist conditions, and performance decline from dehydration have significantly restricted the efficacy and applicability of hydrogel-based electrodes. In this thesis, we report a high-performance hydrogel epidermal electrode patch for …

Review Of The Potential Use Of Poly (Lactic-Co-Glycolic Acid) As Scaffolds In Bone Tissue Recovery, Kushendarsyah Saptaji, Asriyanti Asriyanti, Nisa Khoiriyah, Laely Muryanti, Iwan Setiawan

Makara Journal of Science

Scaffolds are used as temporary tissue in the human body to expedite healing. Biocompatible materials play a vital role in the field of tissue engineering. Therefore, they can be used to reduce human pain as soon as possible. Polymeric materials are widely used to replicate bone tissue. Poly(lactic-co-glycolic acid) (PLGA) is a potential material for bone tissue scaffolds because of its superior properties, including compatibility with the human body. Accordingly, adding hydroxyapatite and introducing different fabrication methods can enable the production of PLGA scaffolds with good abilities to help cells grow, expand, differentiate, and proliferate. The paper reviews the current …

Development Of An In Vitro 3-Dimensional Co-Culture Human Colorectal Cancer Model In Microfluidic Devices, Abby Jens

Master's Theses

Colorectal cancer is the second most common cause of cancer-related deaths in the United States, with the relative 5-year survival rate for distant stage cancer being only 14%. The most common treatment for colorectal cancer is with chemotherapeutic drugs; however, the discovery of these drugs is costly, time-consuming, and often requires the use of animal models that do not yield results that translate to clinical trials. Due to these shortcomings, researchers seek to develop physiologically relevant in vitro tumor models that more accurately mimic the tumor microenvironment for cheaper and faster high-throughput drug screening. The aim of this research was …

Optimal Additive Fabrication Of Patient-Specific Bone Tissue Scaffolds Through Material Formulation, Computational Flow Simulation, And Material Deposition Monitoring, Ethan O’Malley

Theses, Dissertations and Capstones

The advancement of additive manufacturing technologies has opened new avenues for fabricating biocompatible and structurally functional bone tissue scaffolds, essential in treating osseous fractures, defects, and diseases. This research aims to develop mechanically strong, dimensionally precise, and patient-specific porous bone tissue scaffolds that provide both structural integrity and biological functionality. Through three interconnected studies, several key challenges in the fabrication of these structures using the PME additive manufacturing process are addressed. First, the influence of polysaccharide and hydroxyapatite concentrations on the compressive modulus of PME-printed porous scaffolds is investigated. By creating structures with varying hydroxyapatite and polysaccharide compositions, the study …

Numerical Design, Fabrication, And Characterization Of Porous Tissue Scaffolds For Bone Regeneration, Brandon Coburn

Theses, Dissertations and Capstones

With the recent advancements within biomedical engineering of bone tissue scaffolds, there is still a need to develop mechanically robust and biocompatible with low immunogenicity for bone regeneration. Additionally, the evaluation of the fluid dynamics of the porous Triply Periodic Minimal Surfaces (TPMS) bone scaffold also shows the need for investigation due to the complex fluid interaction of hemodynamics that occurs with the scaffold internal and external domains. To aid in the development of treating bone fractures, defects, and diseases. Furthermore, with the induction of a wide variety of TPMS architecture that yields different topologies, the Convolutional Neural Network (CNN) …

Long-Term Simulation Of Stem Cell Mechanobiology, Manoochehr Rabiei

Mechanical and Aerospace Engineering Dissertations - Archive

An accurate representation of cellular mechanobiology necessitates the inclusion of subcellular elements characterized by minute masses and dimensions. These minute objects yield multiscale dynamic models with disproportionate terms, which require inordinate amounts of computational time to simulate. The computational requirements limit the time span of the simulation to time histories shorter than one second, even when employing supercomputers. This work presents a high-speed approach to simulating the mechanobiology of stem cells. The proposed approach separates the computational time from the size, and distribution, of masses of the subcellular elements, enabling the simulation of weeks-long cellular processes within hours on a …

Dihydroethidium-Derived Fluorescence In Electrically Stressed Cells Indicates Intracellular Microenvironment Modifications Independent Of Ros, Esin B. Sözer, Iurii Semenov, P. Thomas Vernier

Bioelectrics Publications

Intracellular reactive oxygen species (ROS) generation is widely suggested as a trigger for biological consequences of electric field exposures, such as those in electroporation applications. ROS are linked with membrane barrier function degradation, genetic damage, and complex events like immunological cell death. Dihydroethidium (DHE) is commonly used to monitor ROS in cells. DHE is linked to intracellular ROS by a primary oxidation product, Ethidium (Eth⁺), that shows increased fluorescence upon binding to polynucleotides. We observed changes in DHE-derived fluorescence in Chinese hamster ovary (CHO) cells post 300-ns electric pulse exposures, comparing them to tert-butyl-hydroperoxide (t-BHP) induced oxidative stress. …

Quantification Of Antiviral Drug Tenofovir (Tfv) By Surface-Enhanced Raman Spectroscopy (Sers) Using Cumulative Distribution Functions (Cdfs), Marguerite R. Butler, Jana Hrncirova, Meredith Clark, Sucharita Dutta, John B. Cooper

Chemistry & Biochemistry Faculty Publications

Surface-enhanced Raman spectroscopy (SERS) is an ultrasensitive spectroscopic technique that generates signal-enhanced fingerprint vibrational spectra of small molecules. However, without rigorous control of SERS substrate active sites, geometry, surface area, or surface functionality, SERS is notoriously irreproducible, complicating the consistent quantitative analysis of small molecules. While evaporatively prepared samples yield significant SERS enhancement resulting in lower detection limits, the distribution of these enhancements along the SERS surface is inherently stochastic. Acquiring spatially resolved SERS spectra of these dried surfaces, we have shown that this enhancement is governed by a power law as a function of analyte concentration. Consequently, by definition, …