Doctor of Philosophy, Case Western Reserve University, 0, Biomedical Engineering

Brain-computer interfaces (BCIs) bridge the gap between dysfunctional central nervous system circuitry and prosthetic devices for individuals with somatic function loss. Intracortical microelectrodes (IMEs) record action potentials and transmit signals through BCI systems to enable external device functionality for neurorehabilitation. Although neural interfaces address the clinical need for restoring neurological function, IMEs face significant biological challenges. The initial rupturing of the blood-brain barrier (BBB) and chronic neuroinflammatory response can lead to IME failure. One strategy to mitigate biological response involves using anti-inflammatory drugs like dexamethasone (DEX), which suppress pro-inflammatory genes. However, systemically administered pharmaceuticals lack targeting functionality, limiting their therapeutic potential. This dissertation explores improving IME longevity by mitigating neuroinflammation and resealing the BBB through the use of a drug-loaded bio-inspired nanoparticle. Our approach employs synthetic platelet-inspired nanoparticles (SPINs) designed to leverage platelet physiology for vascular wound healing. Using IHC, we evaluated SPINs' ability to target IME sites, reduce BBB permeability, and decrease the presence of activated glial cells. Within the next chapter, we conducted the first omics analysis of SPINs as a drug delivery vehicle for DEX to target chronic inflammation at IME sites. This analysis revealed that encapsulating DEX alters its biodistribution, providing insights not observed with IHC. Multiple doses of DEX-loaded SPINs (SPIN-DEX) demonstrated potential to extend IME longevity by modulating gene expression to reduce neuroinflammation and promote BBB healing. Nanoparticle-based therapies enable adaptable dosing that can be informed by transcriptomic data, offering a promising solution for enhancing IME performance. By addressing chronic inflammation and BBB repair, SPIN-DEX provides a comprehensive approach t (open full item for complete abstract)

Committee: Andrew Shoffstall (Advisor); Efstathios Karathanasis (Committee Chair); Jeffrey Capadona (Committee Member); Andrew Crofton (Committee Member) Subjects: Biomedical Engineering; Biomedical Research; Genetics; Neurosciences

Doctor of Philosophy in Regulatory Biology, Cleveland State University, 2022, College of Sciences and Health Professions

Transplantation requires that an organ be removed from the circulation of the donor and then reintroduced to the circulation of the recipient. Organs from deceased donors are often removed from the donor in one hospital and then transported on ice to another hospital for the transplant procedure. Consequently, transplanted organs are subjected to varying periods of ischemia before reperfusion in the recipient. This results in ischemia reperfusion injury (IRI) to the organ. For transplanted kidneys, IRI is frequently severe enough to cause delayed function requiring dialysis and even total failure of the graft. Identifying mechanisms that mediate this injury remains a crucial goal of transplantation. It is known that IRI causes a surge of apoptosis. During normal homeostatic turnover of cells, apoptotic bodies are cleared without inducing inflammation or immune responses by C1q, the initial component of the complement system. In patients with the rare genetic deficiency of C1q, apoptotic bodies are not effectively cleared and immune responses develop to autoantigens in the apoptotic bodies. We examined the role of C1q in modulating the early immune response to IRI in renal transplants by investigating the absence of C1q on early graft injury in an MHC mismatched murine transplant model. We found that A/J kidney grafts transplanted into C1q KO mice exhibited high levels of urinary injury marker, neutrophil gelatinase associated lipocalin (Ngal) within 1 and 2 days posttransplant and decreased survival compared to WT mice. Immunohistology demonstrated increased platelet aggregates in the renal medulla typical of unresolved ischemia induced injury in grafts undergoing early rejection 5 days after transplantation. Sources of C1q were identified during IRI in renal transplants by isolating infiltrating and resident Ly6C+ cell populations from the graft. Resident Ly6C+ cells in the donor kidney were found to express high levels of C1q even 6 days a (open full item for complete abstract)

Committee: William Baldwin PhD (Committee Chair); Keith McCrae MD (Committee Member); Barsanjit Mazumder PhD (Committee Member); Tom McIntyre PhD (Committee Member); Trine Jorgensen PhD (Other); Anna Valujskikh PhD (Other) Subjects: Biology; Cellular Biology; Immunology; Molecular Biology

Doctor of Philosophy, The Ohio State University, 2021, Comparative and Veterinary Medicine

As one of the top causes of cancer in the United States and the leading cause of skin cancer related death, melanoma has been the focus of extensive research in recent years. Such efforts have resulted in remarkable progress in identifying mediators of melanoma oncogenesis and resistance to therapy, prognostication, diagnosis, and management of melanoma patients. However, the translation of these innovations to less common presentations of melanoma, such as ulcerated cutaneous melanoma and vulvovaginal melanoma, which characteristically have a significantly reduced prognosis, has been limited. Thus, additional studies to identify the molecular mediators contributing to aggressive biologic behavior observed with ulcerated cutaneous melanoma and melanomas originating from gynecologic sites are needed. microRNAs are small, non-coding RNA molecules that function to inhibit the expression of specific target genes. Through this action microRNAs can function as either tumor suppressors or oncogenes in cancer. Patterns of microRNA expression in ulcerated cutaneous melanoma are not well defined, and have not been examined in melanomas originating from gynecologic sites. We hypothesized unique patterns of microRNA expression occur with each of these presentations of melanoma that inversely correlate with the expression of microRNA target genes. Using the Nanostring platform the microRNA and mRNA expression patterns in ulcerated melanomas, vaginal melanomas, and vulvar melanomas were characterized. This resulted in identification of 24 differentially expressed microRNAs (p<0.05) and 21 differentially expressed mRNA transcripts (p < 0.01) in ulcerated melanoma, 21 microRNAs and 17 mRNA transcripts with differential expression in vaginal melanoma (p < 0.01), and 47 microRNAs and 89 mRNA transcripts with differential expression in vulvar melanoma (p < 0.01). Using mean expression patterns and correlation analysis across individual samples between microRNAs a (open full item for complete abstract)

Committee: William Carson MD (Advisor); Naduparambil Jacob (Committee Member); Krista La Perle PhD, Dipl. ACVP (Committee Member); Xue-Feng Bai MD, PhD (Committee Member) Subjects: Biology; Molecular Biology; Oncology

Doctor of Philosophy, The Ohio State University, 2014, Integrated Biomedical Science Graduate Program

One-third of the world population is infected with Mycobacterium tuberculosis (M.tb), the causative agent of tuberculosis, which leads to 1.3 million deaths annually. M.tb is a host-adapted intracellular pathogen of macrophages. A complex, evolutionally adaptive relationship exists between M.tb and the host during which the pathogen evades and subverts the immune response mounted by the macrophage. Understanding the interactions during primary infection between the macrophage and M.tb are important as they determine outcomes of infection and course of disease. In this dissertation we examined the roles of microRNAs (miRNA) and MAPK pathways in M.tb infection of primary human macrophages and identified two mechanisms through which M.tb can down-regulate macrophage immune responses and promote its intracellular survival. We determined the miRNA expression profile of M.tb-infected monocyte-derived macrophages (MDM) by the NanoString nCounter miRNA Expression Assay and identified a number of miRNAs that were differentially expressed relative to the non-infected controls 24 h and 72 h after M.tb infection. Among the up-regulated macrophage miRNAs at 72 h after M.tb infection were miR-132 and miR-26a, which we show down-regulates expression of the transcriptional activator p300, a component of the IFN-gamma signaling pathway that mediates transcriptional responses to IFN-gamma in macrophages. Our data suggest that during human M.tb infection there is decreased capacity for macrophages to be activated by IFN-gamma and perform microbicidal functions. In addition, we show that the expression of the MAP3K Tpl-2, which was previously identified as a host defense molecule against M.tb in a murine knockout model, is down-regulated during M.tb infection in human primary macrophages. Concurrently, we observed increased mRNA levels of Tpl-2, suggesting a role for miRNAs in targeting Tpl-2 mRNA or other post-translational regulatory mechanisms such as loss of stabilization by (open full item for complete abstract)

Committee: Larry Schlesinger MD (Advisor); Amal Amer MD, PhD (Committee Member); Clay Marsh MD (Committee Member); Stephanie Seveau PhD (Committee Member) Subjects: Immunology; Microbiology

Doctor of Philosophy, The Ohio State University, 2011, Veterinary Biosciences

The complex retrovirus human T-lymphotrophic virus type 1 (HTLV-1) is the causative agent of adult T-cell leukemia (ATL) and a variety of inflammatory disorders. Only about 5% of infected individuals develop ATL and then only after a 30 to 50 year clinical latency period. Reasons for this are incompletely understood. Viral modulation of viral and cellular protein expression is thought to be a major contributor to the phenomenon. HTLV-1 Tax has a prominent role in modulation activities. Key Tax activities include altering cellular response to DNA damage, apoptosis signals, and cell cycle regulation. However, expression of Tax and some Tax modulated activities increase the probability of the virus being detected and eliminated by the immune system. The virus mediates this risk by employing other viral proteins to modulate the activities and effects of Tax. HTLV-1 p30 (p30), the focus of this thesis, is one of the viral proteins that provides a counter balance to the activities of Tax. p30 selectively retains tax mRNA in the nucleus, competes with Tax for limited transcriptional elements and transcriptionally regulates both HTLV-1 and cellular gene expression. Improving our understanding of how p30 accomplishes these activities will improve our ability to combat HTLV-1 infections. Critical to understanding the mechanisms of action of p30 is knowledge of which amino acid residues and post-translational modifications are required for the functions of p30. In chapter 2, we used bioinformatics analysis to predict motifs and post-translational modifications of p30. Our bioinformatics studies revealed 11 highly conserved serines, all predicted to be phosphorylated. To test the presence of phosphorylation we used P32 labeling and mass spectrometry. Mass spectrometry revealed two serines at positions 88 and 102 that were phosphorylated. In chapter 3 we explored the impact of p30 on expression of a subset of genes associated with cellular response to DNA damage. Two complemen (open full item for complete abstract)

Committee: Michael Lairmore DVM, PhD (Advisor); Mamuka Kvaratskhelia PhD (Committee Member); Kathleen Boris-Lawrie PhD (Committee Member); Jesse Kwiek PhD (Committee Member) Subjects: Molecular Biology; Virology