Microbiology Commons^™

Superresolved Three-Dimensional Analysis Of The Spatial Arrangement Of The Human Immunodeficiency Virus Type-1 (Hiv-1) Envelope Glycoprotein At Sites Of Viral Assembly, Carmen Anne Buttler

Electronic Theses and Dissertations

Human Immunodeficiency Virus type 1 (HIV-1) replicates by forcing infected host cells to produce new virus particles, which assemble form protein components on the inner leaflet of the host cell's plasma membrane. This involves incorporation of the essential viral envelope glycoprotein (Env) into a structural lattice of viral Gag proteins. The mechanism of Env recruitment and incorporation is not well understood. To better define this process, we seek to describe the timing of Env-Gag encounters during particle assembly by measuring angular positions of Env proteins about the surfaces of budding particles. Using three-dimensional superresolution microscopy, we show that Env distributions …

Molecular Determinants Of Trim5Α Restriction And Recruitment Of Autophagic Effectors, Sabrina Imam

Dissertations

TRIM5α is an anti-viral restriction factor that inhibits the lifecycle of retroviruses. TRIM5α binds to and forms a hexameric lattice around the retroviral capsid, thereby initiating its antiviral activities, which include: (1) inhibition of viral infection; (2) inhibition of viral reverse transcription; (3) disassembly of the capsid; and (4), activation of innate signaling pathways. The formation of this assembly also activates the E3 ubiquitin ligase function of TRIM5α. Ubiquitin modification is associated with directing substrates to particular cellular pathways. We and others have shown that TRIM5α cytoplasmic bodies colocalize with proteins involved in the autophagy pathway, and we hypothesized that …

The Effects Of The Hiv-1 Tat Protein And Morphine On The Structure And Function Of The Hippocampal Ca1 Subfield, William D. Marks

Theses and Dissertations

HIV is capable of causing a set of neurological diseases collectively termed the HIV Associated Neurocognitive Disorders (HAND). Worsening pathology is observed in HIV+ individuals who use opioid drugs. Memory problems are often observed in HAND, implicating HIV pathology in the hippocampus, and are also known to be exacerbated by morphine use. HIV-1 Tat was demonstrated to reduce spatial memory performance in multiple tasks, and individual subsets of CA1 interneurons were found to be selectively vulnerable to the effects of Tat, notably nNOS+/NPY- interneurons of the pyramidal layer and stratum radiatum, PV+ neurons of the pyramidal layer, and SST+ neurons …

Human Herpesvirus 6a Infection And Immunopathogenesis In Humanized Rag2-/-Γc-/- Mice And Relevance To Hiv/Aids And Autoimmunity, Anne Tanner

Theses and Dissertations

Human herpesvirus 6A (HHV-6A) has yet to be definitively linked to a specific disease. This is due in part to the ubiquitous nature of the virus. Humanized Rag2^-/-γc-/- (Rag-hu) mice were tested to determine if these were a suitable animal model to study the virus. Both cell-free and cell-associated virus was used for infection and both were found to be efficient at infecting the mice. Viral DNA was found in the plasma and cellular blood fractions, bone marrow, lymph node, and thymus, indicating successful infection and propagation of the virus in vivo. The CD3+CD4- population was depleted, while the …

Hiv Vaccines: Progress, Limitations And A Crispr/Cas9 Vaccine, Omar A. Garcia Martinez

Biology: Student Scholarship & Creative Works

ABSTRACT: The HIV-1 pandemic continues to thrive due to ineffective HIV-1 vaccines. Historically, the world’s most infectious diseases, such as polio and smallpox, have been eradicated or have come close to eradication due to the advent of effective vaccines. Highly active antiretroviral therapy is able to delay the onset of AIDS but can neither rid the body of HIV-1 proviral DNA nor prevent further transmission. A prophylactic vaccine that prevents the various mechanisms HIV-1 has to evade and attack our immune system is needed to end the HIV-1 pandemic. Recent advances in engineered nuclease systems, like the CRISPR/Cas9 system, have …

Nf45 And Nf90 Bind Hiv-1 Rna And Modulate Hiv Gene Expression, Yan Li, Michael Belshan

Nebraska Center for Virology: Faculty Publications

A previous proteomic screen in our laboratory identified nuclear factor 45 (NF45) and nuclear factor 90 (NF90) as potential cellular factors involved in human immunodeficiency virus type 1 (HIV-1) replication. Both are RNA binding proteins that regulate gene expression; and NF90 has been shown to regulate the expression of cyclin T1 which is required for Tat-dependent trans-activation of viral gene expression. In this study the roles of NF45 and NF90 in HIV replication were investigated through overexpression studies. Ectopic expression of either factor potentiated HIV infection, gene expression, and virus production. Deletion of the RNA binding domains of NF45 …

Defining And Characterizing The Step In The Hiv-1 Viral Life Cycle Affected By Fullerene Derivatives, Zachary Sean Martinez

Open Access Theses & Dissertations

Fullerene derivatives, both C60 and C70, were synthesized and characterized to test their activity against HIV-1 infection. The derivatives tested have previously been reported to inhibit HIV-1 replication and/or in vitro activity of reverse transcriptase. It was found that viruses produced in the presence of low micromolar concentrations of most of these fullerene derivatives exhibit a reduction in viral infectivity greater than 99%. Quantification of virion-associated viral RNA and p24 indicates that RNA packaging and viral production were unremarkable in these viruses. These compounds did not affect infectivity of mature virions, indicating no effect on the early steps of the …

Influence Of The Anti-Hiv Drug Elvitegravir On Chlamydial Development And The Characterization Of Chlamydial Polymorphic Membrane Protein Expression In Herpes Simplex Virus (Hsv)/C. Trachomatis Co-Infected Cells, Hena Yakoob

Undergraduate Honors Theses

Chlamydia trachomatis is the most common bacterial agent of sexually transmitted infections worldwide and a common co-infection in AIDS patients. Chlamydial genital tract infections are often asymptomatic; therefore many infections go untreated and result in complications like chronic inflammation, ectopic pregnancy, and pelvic inflammatory disease. Chlamydia share a unique developmental cycle and under stress, can enter a state known as persistence, in which the bacteria are noninfectious but still viable. Removal of the stressor allows the chlamydiae to re-enter and complete the developmental cycle. Exposure to low-dose quinolones can cause the chlamydiae to enter persistence and halt the developmental cycle. …

Hiv Prevalence In Blood Donors And Recipients In Pakistan: A Meta-Analysis And Analysis Of Blood-Bank Data, Bushra Moiz, Barkat Ali, Muhammad Hasnain Chatha, Ahmed Raheem, Hasan Abbas Zaheer

Department of Pathology and Laboratory Medicine

Background:
The first instances of HIV-antibody detection in donated blood in Pakistan were reported in 1988. Since then, documentation of HIV in blood donors and of rates of transmission via transfusion has been limited. Previously assumed to have a low prevalence, HIV is an increasing health concern in Pakistan. Since there is no national, centralized blood-banking system, there are no reliable data on which to base estimated risks of transfusion-associated HIV infection. This study was therefore conducted to estimate the prevalence of HIV in blood donors and recipients in Pakistan between 1988 and 2012.
Methods:
Meta-analyses were undertaken of reported …

Recombination And Evolution Of Hiv In Vivo, Sterling Adams, Dr. Bradford Berges

Journal of Undergraduate Research

Worldwide we have known about the Human Immunodeficiency Virus since the early 80’s, and since that time there has been research to find different “cures” for the disease that the virus causes called: acquired immunodeficiency syndrome (AIDS). Since the epidemic has started nearly 30 million people have died from AIDS related causes, and there are nearly 34 million people worldwide that are HIV positive. One of the striking features of the virus that makes it so difficult to treat is its rapid ability to evolve. When looking at an HIV positive patient, statistically speaking, if you were to take every …

Measles Virus And Its Interactions With Follicular Dendritic Cells, Michael J. Lloyd, Dr. Gregory F. Burton

Journal of Undergraduate Research

Measles virus continues to be a major cause of death in most third-world countries and a considerable threat to the health of every country. Infection with measles is thought to be associated with the fatal, late-infection disease subacute sclerosing panencephalitis (SSPE) (3). It is thought that Measles virus is retained by the body following infection until it mutates, crosses the blood-brain barrier to infect and destroy brain tissue, killing the host.

Transcription Upregulation Of Hiv By Fdc, Nathan R. York, Dr. Gregory R. Burton

Journal of Undergraduate Research

The search to understand Human Immunodeficiency Virus (HIV) and the progression of the disease that it causes, AIDS, has led scientists to delve further and further into the intricacies of viral mechanics. Although not considered living organisms by many scientists, these entities manage to find ways to enter, replicate, and thrive within the cells of their hosts. As we study any one particular virus, insights into many viruses can be gained.

In Vitro Effects Of Follicular Dendritic Cells On Proliferation Of Hiv Infected T Cells, Jesse Rowley, Dr. Gregory Burton

Journal of Undergraduate Research

Human Immunodeficiency Virus (HIV), the cause of AIDS, has eluded successful treatment since its discovery in the early 1980s. HIV is a retrovirus that infects and eventually destroys CD4+ T cells. In HIV infected individuals it is believed that during the longest phase of infection (latency) most viral production takes place in and around the germinal centers of secondary lymphoid tissues. Follicular dendritic cells (FDCs) are a unique component of the germinal center, and previous studies done in our laboratory have suggested that FDCs may augment viral replication and/or infection within the germinal center.

Follicular Dentritic Cells And Retention Of Hiv Quasi-Species, Candace Mcnaughton, Dr. Gregory Burton

Journal of Undergraduate Research

HIV infects millions of people worldwide; in the year 2000 alone, more than 3 million people died from AIDS (Acquired Immunodeficiency Syndrome) as a result of HIV infection1. In countries, such as the United States, where effective treatment is affordable, highly active antiretroiviral therapy (HAART) can reduce viral blood loads to currently undetectable levels2. Unfortunately, the side effects of HAART can be severe, resulting in noncompliance, and upon its termination, HIV levels rapidly rebound. Several viral reservoirs within the body have been identified, including the follicular dendritic cell (FDC) network3. FDCs trap HIV antibody complexes for long periods of time …

Sequence Analysis Of Hiv Quasi Species In Vivo, Eryn Barber Hadley, Dr. Greg Burton

Journal of Undergraduate Research

Human Immunodeficiency Virus (HIV) is the causative agent of Acquired Immunodeficiency Syndrome (AIDS). There is currently no cure for HIV infection, and AIDS has been reported as the fourth highest killer in the world [1]. The initial success of the drug cocktail used in Highly Active Anti-Retroviral Therapy (HAART) has made the possibility of a cure for AIDS seem attainable, however the persistence of virus reservoirs makes this extremely difficult and leads to a rebound of viral load [2]. The known reservoirs of HIV include latently infected T cells, macrophages and follicular dendritic cells.

Fc Receptors In Hiv Trapping And Retention On Follicular Dendritic Cells, Daniel Willis, Dr. Gregory Burton

Journal of Undergraduate Research

The development of HighlyActive Antiretroviral Therapy (HAART) against the HIV virus created a temporary excitement regarding a possible cure for HIV. This optimism resulted due to the fact that HAART blocked active HIV replication and reduced the level of HIV in the bloodstream to below standard limits of detection. However, it was soon discovered that HIV blood levels were restored shortly after cessation of HAART. This led to the discovery of HIV reservoirs, or sites where latent virus is harbored. It is this harbored virus that actively replicates and replenishes HIV viral loads when HAART is discontinued.

Follicular Dendritic Cells (Fdcs) And Sparing Of Cd4+ T Cells From Hiv/Cd62l Triggered Apoptosis, Devon C. Cole, Dr. Grey Burton

Journal of Undergraduate Research

Both B and T lymphocytes intimately interact with follicular dendritic cells (FDCs) in lymphoid follicles of secondary lymphoid tissue (e.g., spleen, lymph node, and tonsils). FDCs trap and retain antigens needed to induce and maintain potent memory antibody responses. FDCs contribute both antigen dependent and independent signals to B lymphocytes residing in the microenviroment of germinal centers in secondary lymphoid tissue, which contributes to the optimal activation of these cells as well as T lymphocytes. One important contribution of FDCs to B lymphocytes is signaling that spares these cells from programmed cell death. As B cells differentiate in germinal centers, …

Hiv In The Immune System: The Role Of Specialized Follicular Dendritic Cells In Promoting Viral Disease, Jacob D. Estes, Dr. Gregory F. Burton

Journal of Undergraduate Research

Human Immunodeficiency Virus (HIV) has become a world wild epidemic affecting millions of people across the globe. Even in the face of potent antiviral drugs which are only available in first world countries, HIV continues to evade intervention strategies and eventually destroy the body’s immune system. During the longest stage of HIV disease, clinical latency, much of active infection is confined to the germinal centers of secondary lymphoid tissue (1). Here HIV is trapped on the surface of follicular dendritic cells (FDC) which reside in this region of all secondary lymphoid organs (2). Large amounts of HIV localize on FDC …

The Implications Of Subtype Diversity Of Hiv-1 For Vaccine Development, Ryan Peterson, Dr. Keith A. Crandall

Journal of Undergraduate Research

HIV’s ability to infect a host and grow without killing the host allows the virus to accumulate genetic diversity. Over time, HIV has diverged into a number of subtypes, differing up to 30% in their nucleic acids (2). For this reason, one of the greatest problems with vaccine development is that different subtypes express different protein variants (3). With the increase of HIV recombination and human travel, geographical patterns subtypes are becoming mixed, thus allowing the virus to explore new genetic variants and evade vaccine effectiveness (5).

Follicular Dendritic Cells, Hiv And Haart Treatment, Jason Meyer, Dr. Gregory Burton

Journal of Undergraduate Research

The use of highly active antiretroviral therapy (HAART) for HIV-infected patients can result in the reduction of plasma viral RNA levels to nearly undetectable levels. However, the existence of replication competent virus from chronically infected CD4+ T cells despite apparently successful HAART treatment suggests the existence of protective reservoirs in the body that protect virally infected cells from the effects of HAART treatment (1). Follicular dendritic cells (FDC) are specialized cells that exist primarily in secondary lymphoid tissue. The purpose of my research was to examine my hypothesis that FDC act as such reservoirs by protecting infected cells from the …

Transfer Of Hiv From Fdc To Macrophages, Michael Fuller, Dr. Gregory Burton

Journal of Undergraduate Research

Over the last semester, I have been engaged in studying the ability of macrophages to pick up HIV from follicular dendritic cells (FDC) in the follicles of the lymph nodes. Research by Dr. Gregory F. Burton of Brigham Young University has shown that HIV virions held on the dendrite processes of follicular dendritic cells in immune complex form are still infectious, and can infect T cells. Research by Dr. Suzanne Gartner at Johns Hopkins University has shown homology between HIV isolated from the brain to HIV in the lymph nodes. Tying these data together, I hypothesized that macrophages are able …

Development Of Humanized Mice As A Model For The Study Of Neuro-Aids, German Cuadra, Dr. Bradford Berges

Journal of Undergraduate Research

Our main goal of this project was to document the existence of human macrophages in the brain of humanized mice. After the accomplishment of this goal, we planned to infect humanized mice with HIV and find out if these human macrophages support infection in mouse brain tissue. We hypothesize that humanized mice will have human macrophages engrafted in the brain and that these cells will become infected with HIV via normal pathways after introduction of virus via other routes, as in humans. By identifying these cells in humanized mice, we plan to develop a mechanism to study the relationship between …

Evolution Of Human Immunodeficiency Virus Type 1 Clade C Envelope V1–V5 Region During Disease Progression In Non-Human Primate Model, For Yue Tso

School of Biological Sciences: Dissertations, Theses, and Student Research

Human immunodeficiency virus type 1 (HIV-1) clade C strain is the fastest spreading HIV-1 strain globally, especially in Africa. It has been decades since the acquired immune deficiency syndrome (AIDS) pandemic first started. However, an effective anti-HIV-1 vaccine is not yet available, which is partly due to the highly variable nature of HIV-1 envelope gene and the absence of a suitable animal model. Strengthening of the understanding of envelope evolution during disease progression will contribute significantly towards future anti-HIV-1 treatment and preventions.

Non-human primates have been an essential animal model for many biomedical research areas. Using simian-human immunodeficiency virus (SHIV) …

Role Of Post-Translational Modifications In The Hiv Cofactor Activity Of Ledgf/P75, Denisse Adriana Gutierrez

Open Access Theses & Dissertations

see document.

Identifying And Characterizing The Degradative Pathway Of The Retroviral Restriction Factor Rhtrim5Α, Rachel Nelson

Master's Theses

Human immunodeficiency virus 1 (HIV-1) is a lentivirus that progresses to acquired immunodeficiency syndrome (AIDS). The protein TRIM5alpha from rhesus macaques (rhTRIM5alpha) restricts HIV-1 by blocking infection after entry of the virion into cells. Treatment of rhTRIM5alpha expressing cells with inhibitors to a cellular degradation pathway, the proteasome, partially relieves restriction but does not inhibit rhTRIM5alpha protein turnover. The role of a second degradation pathway, the autophagy-lysosomal pathway, in TRIM5alpha mediated restriction has not been explored.

In the present study, we demonstrate that rhTRIM5alpha is degraded by chaperone mediated autophagy (CMA). Inhibition of CMA alters rhTRIM5alpha localization and turnover, while …

Developing A Quantitative Pcr Assay For Detecting Viral Vector Shedding From Animals, Swathee Chinnasamy

Browse all Theses and Dissertations

Replication deficient viruses have been used widely for replacing, repairing, and deleting target genes. These recombinant viruses are tested on research animals or patients in clinical trials. Although viral vectors distribute in the body, they are also disseminated into the environment through secretion and excretion processes. By studying the extent of shedding, a proper risk assessment can be performed and appropriate biocontainment can be achieved. Adenoviral and lentiviral vectors were produced from commercially available kits. The transgene present in both vector systems was the lacZ reporter gene encoding for β-galactosidase. Primers and probes were designed for the encapsidation region of …

The Role Of Sumoylation Of Ledgf/P75 In Hiv-1 Infection, Murilo Tadeu Domingues Bueno

Open Access Theses & Dissertations

The lens epithelium-derived growth factor (LEDGF) proteins p75 and p52 are transcriptional co-activators that protect cells from stresses through modulation of stress and heat shock-related genes. Besides regulating such genes, LEDGF/p75 is also important in the process of HOX gene expression and leukemia transformation driven by the MLL histone methyl transferase complex. By exploiting a similar mechanism of interaction between LEDGF/p75 and MLL, the HIV-1 viral protein Integrase (IN) associates with LEDGF/p75 in order to execute efficient viral DNA integration. This present work has identified that LEDGF proteins are posttranslationally modified by SUMO-1 and -3. SUMOylation was found to target …

Do Hospitalists Or Physicians With Greater Inpatient Hiv Experience Improve Hiv Care In The Era Of Highly Active Antiretroviral Therapy? Results From A Multicenter Trial Of Academic Hospitalists, John A. Schneider, Qi Zhang, Andrew Auerbach, David Gonzales, Peter Kaboli, Jeffrey Schnipper, Tosha B. Wetterneck, David L. Pitrak, David O. Meltzer

Community & Environmental Health Faculty Publications

Background. Little is known about the effect of provider type and experience on outcomes, resource use, and processes of care of hospitalized patients with human immunodeficiency virus (HIV) infection. Hospitalists are caring for this population with increasing frequency.

Methods. Data from a natural experiment in which patients were assigned to physicians on the basis of call cycle was used to study the effects of provider type—that is, hospitalist versus non hospitalist—and HIV-specific inpatient experience on resource use, outcomes, and selected measures of processes of care at 6 academic institutions. Administrative data, inpatient interviews, 30-day follow-up interviews, and the National Death …

Genetic Variation In Mother-Child Acute Seroconverter Pairs From Zambia, Federico G. Hoffmann, Xiang He, John T. West, Philippe Lemey, Chipepo Kankasa, Charles Wood

Nebraska Center for Virology: Faculty Publications

Objective: To characterize the envelope (env) glycoprotein of HIV-1 in mother-infant pairs (MIP) that underwent near simultaneous or acute-phase seroconversion, we examined the env sequence of the transmitted viruses and compare viral evolution within the pair.

Design: Three MIP from a Zambian cohort that seroconverted at the same sampling time were identified and followed longitudinally.

Methods: The V1-V5 region of the HIV-1 env gene was sequenced for each sample collected. Phylogenetic and population genetics analyses were carried out to subtype the viruses, estimate relationships among viral genotypes, and compare molecular evolution between the viral populations. …

The Potential Role Of Probiotics In Reducing Poverty-Associated Infections In Developing Countries, Kingsley Anukam

Data and Test Instruments

Probiotics are defined by the Food and Agricultural Organization/ World Health Organization as “live microorganisms which when administered in adequate amounts confer a health benefit on the host” [1]. The potential benefits of their use have not been adequately investigated, especially in the developing world. Japan introduced Yakult, a probiotic fermented food drink in 1935, and in the Northern hemisphere, research and use of probiotics has gained an unprecedented momentum in the last decade [2]. Use of probiotics is not uncommon in Europe [3], but in many developing countries use of probiotics in its present definition is a foreign concept. …