Medicine and Health Sciences Commons^™

Humanized Mice For Brain Infection Of Emerging Viruses, Edward Makarov

Theses & Dissertations

Studies on the pathogenesis of emerging viruses that present a global threat are critical for pathogen classification and therapeutic development. Humanized mice enable investigation of viral pathogens, including Human immunodeficiency virus (HIV-1), Zika virus (ZIKV), Coronavirus 2 (SARS-CoV-2), and Dengue virus (DENV), offering an advanced understanding into the mechanisms of viral perseverance in its natural human host cells and for therapeutic discovery. Realizing the diverse dynamics of various viral infections with the capacity to establish an innovative acuity for therapeutics and mechanics when utilizing humanized mice contributes a formerly inaccessible insight into human-specific viral pathogenesis and treatment. We recently developed …

Fire Service Covid-19 Infection Prevention And Control Policy Comparison, Saaddedine Dichari

Theses & Dissertations

To date, there have been over 2.7 million deaths and more than 126 million cases attributed to the COVID-19 pandemic (JHU, 2021). This pandemic has affected nearly every aspect of daily life. Among those impacted are U.S. firefighters, as they provide many services beyond simply extinguishing structure fires and are frequently dual certified as emergency medical technicians. Many of the victims of this pandemic have relied on first responders to provide them with emergency medical care and hospital transport. When caring for these infected patients, firefighters have an increased risk of exposure and must be provided with adequate …

Neurocognitive Impairment In People Living With Human Immunodeficiency Virus (Hiv): Risk Factors And Mortality, Zaeema Naveed

Theses & Dissertations

Despite the widespread use of combination antiretroviral therapy (cART), HIV-associated neurocognitive impairment (NCI) persists in people living with HIV (PLWH) with clinical and public health implications. Studies have generated inconsistent results regarding etiological factors for NCI in PLWH and a brief user-friendly predictive tool is desirable in clinical practice to assess the probability of having NCI in PLWH. Furthermore, factors associated with clinically meaningful decline in neurocognitive status and survival disadvantage for patients with NCI are understudied in the post-cART era. The goal of this dissertation was to investigate factors associated with baseline NCI and neurocognitive decline and the association …

Neural Oscillatory Activity Serving Sensorimotor Control Is Regulated By The Mitochondrial Redox Environment In Health And Disease, Rachel Spooner

Theses & Dissertations

Despite effective regimens of combination antiretroviral therapy, individuals with HIV are still at higher risk for developing forms of cognitive impairment, with one of the most common behavioral abnormalities to manifest being motor dysfunction. This is an important consideration, as deficits in motor control likely contribute to higher-order cognitive impairments, which together, lead to functional dependencies in the ever-growing aging population of HIV-infected adults. While the neuroanatomical bases of motor dysfunction have recently been illuminated in people living with HIV (PLWH), there remains an open question regarding the molecular processes supporting the circuit-level neuronal dynamics that potentially serve these behavioral …

Development Of Long-Acting Antiviral Drug Nanoformulations, Denise Cobb

Theses & Dissertations

Antiretroviral therapy (ART) has improved the quality and duration of life for people living with human immunodeficiency virus (HIV) infection. However, opportunities to improve its profile abound. ART is limited by putative viral reservoir penetrance, emergence of viral mutations, inherent toxicities, and regimen non-adherence. These highlight the need improved drug delivery schemes. Previously, our lab has demonstrated that targeting mononuclear phagocytes for antiretroviral drug delivery extends drug half-life and improves penetrance into viral reservoirs, addressing these limitations of ART. Herein, we developed synthetic and biologic antiretroviral (ARV) drug nanocarriers improve the pharmacokinetic (PK) and pharmacodynamic (PD) profiles of ARVs through …

Multimodal Neuroimaging Of Hiv And Aging, Brandon Lew

Theses & Dissertations

HIV infection remains a significant contributor to disease burden, and with the success of antiretroviral therapies, the population of people with HIV is aging. A growing literature suggests a relationship between HIV-infection and a profile of age advancement, most notably in molecular studies of epigenetics. However, despite the widely-known high prevalence of HIV-related brain atrophy, functional deficits, and HIV-associated neurocognitive disorder (HAND), epigenetic age advancement has not been linked to HIV-related changes in neuroimaging metrics.

We applied three neuroimaging methods, structural MRI, resting state functional MRI, and resting state MEG, to study the brain structure and function of 121 virally-suppressed …

Theranostics For Antiretroviral Biodistribution And Pharmacokinetics, Brendan M. Ottemann

Theses & Dissertations

RATIONALE: Our laboratories birthed the field of human immunodeficiency virus (HIV) theranostics. The new field allows simultaneous detection (diagnostics) and treatment (therapeutic) for the identification, treatment and inevitable elimination of virus in cell and tissue compartments. By employing theranostics, antiretroviral drugs (ARVs) can be tracked in lymph nodes, gut, spleen and liver. Cellular viral reservoirs including CD4+ T cell populations and mononuclear phagocytes (MP; monocytes, macrophages, microglia and dendritic cells) along with subcellular endosomal structures can now be targeted for drug delivery bringing therapeutics to areas where virus replicates. The overarching idea rests in improving precision targeted ARV delivery. …

Hiv-1 Elimination In Humanized Mice, Hang Su

Theses & Dissertations

Human immunodeficiency virus type one (HIV-1) exclusively infects humans and chimpanzees. Therefore, animal models are required for all investigations of viral pathogenesis, therapy and cure. Immunodeficient mice transplanted with human hematopoietic stem cells, termed humanized mice, support the development of multiple human cell lineages throughout the cell’s life span. To this end, we used humanized mice to evaluate the dynamic changes of host immunologic and viral profiles during both acute and chronic HIV-1 infection. We identified the temporal and spatial distribution of HIV-1 cell and tissue compartment infections and outlined correlations made between viral progression and host immunity by comparing …

Synthesis And Characterization Of Long Acting Darunavir Prodrugs, Mary Banoub

Theses & Dissertations

Patient adherence is critical for ART success to ensure adequate viral suppression, therefore, long-acting antiretrovirals are soon replacing current daily regimens. In recent years, two drugs were successfully transformed into long-acting injectables; CAB LA and RPV LA. These long-acting nanoformulations made it possible to abandon the daily pill burden, instead approximately a bimonthly injection of both drugs is enough to suppress and maintain viral load suppression. Our laboratory has been instrumental in transforming FDA-approved and experimental-HIV medications into long-acting slow effective release drugs, also known as LASER ART. LASER ART consists of slow drug metabolism and high permeability and retention …

Synthesis And Characterization Of Long-Acting Rilpivirine Prodrugs, James R. Hilaire

Theses & Dissertations

Antiretroviral therapy (ART) requires lifelong daily dosing to suppress viral replication, restore or maintain immune function and improve quality of life. As an alternative, long-acting (LA) antiretrovirals (ARVs) aim to deliver therapeutic drug concentrations over an extended period, ultimately requiring monthly or even more extended dosing intervals. Specifically, the success of recent clinical trials examining LA cabotegravir and rilpivirine (CAB and RPV LA) highlight the advent of these novel HIV-1 therapeutics. Further optimization of LA dosage forms are required and rests upon improving dosing frequency, injection volumes and tissue distribution to viral compartments. To this end, we report the synthesis …

Development Of A Long-Acting Nanoformulation Of Dolutegravir For Prevention And Treatment Of Hiv-1 Infection, Brady Sillman

Theses & Dissertations

Dolutegravir (DTG) is a potent human immunodeficiency virus type 1 (HIV-1) integrase strand-transfer inhibitor (INSTI) with a high barrier to viral drug resistance. However, opportunities to improve its profile abound. These include extending the drug’s apparent half-life, increasing penetrance to “putative” viral reservoirs, and reducing inherent toxicities. These highlight, in part, the need for long-acting, slow effective release antiretroviral therapy (LASER ART) delivery schemes. A long-acting (LA) DTG was made by synthesizing a hydrophobic and lipophilic prodrug encased with poloxamer (P407) surfactant. This modified DTG (MDTG) reduced systemic metabolism and polarity, increased lipophilicity and membrane permeability, improved encapsulation, and formed …

Long-Acting Antiretroviral Nanoformulation Development And Subcellular Trafficking, Dongwei Guo

Theses & Dissertations

The introduction of nanoformulated antiretroviral therapeutic regimens is a promising alternative to standard once a day oral treatment of HIV infection. Our lab has pioneered this effort and was successful in harnessing mononuclear phagocytes (monocytes, dendritic cells and macrophages) as nanoformulated drug carriers. The approach was developed as Trojan horses for drug transport, delivery and distribution to sites of viral replication in order to facilitate microbial elimination in HIV sanctuaries. However, the remaining challenges for current antiretroviral nanoformulations include to formulate a broad range of hydrophilic short-acting drugs, and to elucidate the mechanism of sequestered nanoparticles in macrophages at the …

Synthesis And Development Of Long-Acting Abacavir Prodrug Nanoformulations, Dhirender Singh

Theses & Dissertations

Over the past decade, work from our laboratory has demonstrated the potential of targeted nanoformulated antiretroviral therapy (nanoART) to produce sustained high plasma and tissue drug concentrations for weeks following a single intramuscular (IM) administration that can suppress ongoing viral replication and mitigate dose associated viral resistance. While progress has occurred towards developing long-acting nanoformulations for protease and nonnucleoside reverse transcriptase (RT) inhibitors, development of nanoformulations of hydrophilic nucleoside RT inhibitor drugs have remained elusive. Abacavir (ABC); a hydrophilic molecule exhibited limited utilities to develop into long-acting nanoformulation platform. Furthermore, inefficient conversion of ABC to its biological active metabolites; carbovir …

Ccr5 And The Blood Brain Barrier During Hiv-1 Infection And Cell-Cell Communications, Shawna M. Woollard

Theses & Dissertations

Human Immunodeficiency Virus (HIV-1) infection often results in blood-brain barrier (BBB) dysfunction and central nervous system (CNS) impairment. Since most viral strains that cross the BBB and enter the CNS are macrophage-tropic and use the C-C chemokine receptor type-5 (CCR5) to enter and infect target cells, we hypothesized that CCR5 plays a major role in monocytes-endothelial interactions and HIV-induced BBB dysfunction. Because the cytoskeleton is responsible for cellular morphology and motility, we further hypothesized that HIV-induced monocyte-endothelial interactions and transendothelial migration involve cytoskeletal changes and that CCR5 blockers would also affect these changes. To this end we used two small …