Ronald Ellis - US grants

DESCRIPTION (Adapted from the Applicant's Abstract): The social and medical consequences of HIV infection of the central nervous system (CNS) are disability due to neurocognitive disorders, lowered quality of life, and decreased survival. Advances in the understanding of the pathogenesis and treatment of these disorders are vitally important. This research proposal outlines three integrated laboratory and clinical investigations that will examine the sources of CSF RNA, the potential role of the CNS as reservoir for HIV, and how monitoring cerebrospinal fluid (CSF) viral load may guide antiretroviral therapy for the CNS. The first study is an antiretroviral treatment trial designed to maximally diminish CSF viral load in patients with HIV-associated neurocognitive disorders (N = 45). This trial will test the hypothesis that improvement in neurocognitive function may be achieved through a reduction in CSF viral load. In a second study, previously untreated individuals with and without advanced immunosuppression (n=42), will be randomly assigned to CNS penetrating and nonpentrating antiretroviral combination therapies, and the dynamic change of CSF and plasma HIV RNA viral load will be determined serially. This study will test the hypothesis that in late stage disease, productive brain infection is the primary source of HIV in CSF, and that rational therapy requires CNS-penetrating antiretroviral drugs. Both studies will serially document plasma and CSF antiretroviral drug concentrations. A third study, drawing on antemortem and postmortem samples from 10 patients, will assess the phylogenetic relatedness of virus in various systemic and CNS compartments to confirm the hypothesis that as AIDS develops, the predominant HIV genetic variant in CSF resembles that in brain. Similar methodology, applied to CSF obtained from treatment trial participants, will assess the evolution of drug resistant mutations of HIV in the CNS. This research, which will provide groundwork for the rational diagnosis and treatment of HIV infection of the CNS, has a unique collaboration with the HIV Neurobehavioral Research Center for recruitment, neuromedical diagnosis, neuropsychological assessment, and acquisition of antemortem and postmortem samples.

Like most nematodes, Caenorhabditis remanei has two sexes: XO animals become males and XX animals become females. However, Caenorhabditis elegans is hermaphroditic: XO animals are male and XX animals develop as self-fertile hermaphrodites. These hermaphrodites appear female in most respects, but produce sperm during larval development which can be used for self-fertilization. Thus these species provide a system to study how well defined differences in sex-determination arose. In C. elegans, two genes appear to directly control the decision to make sperm: fog-1 and fog-3. Mutations in either gene cause all germ cells to differentiate as oocytes, even in males. Thus, one simple model is that these genes would be active only in male C. remanei and that a crucial step in the evolution of hermaphroditism involved their expression and function in XX individuals of C. elegans. Four approaches will be used to test this model. 1) The C. remanei homologs of fog-1 and fog-3 will be isolated and sequenced. In addition, RNA-mediated interference will be used to determine the function of each gene in C. remanei. 2) Comparison of the promoters for these C. elegans and C. remanei genes should aid in identifying regulatory elements that control transcription. Any identified elements will be tested in transgenic animals. 3) Comparison of the protein products of these genes will help to identify crucial domains and potential regulatory sites. These products will also be tested in transgenic animals. 4) C. elegans will be genetically analyzed to find and characterize new genes that regulate fog-1 or fog-3 which will be subjects for future study in C. remanei. The introductory Genetics course will be amplified to include new material from human genome studies, as it becomes available. Discussion of ethical issues raised by human genomic studies will also be added to the course and new computer technology will be utilized in order to teach students about the power and limitations of the genetic databases available on the Internet.

Insight into the evolution of sexual differences in animals will be enhanced by the results of this investigation of two nematodes with different modes of reproduction. The use of information from the extensive database for C. elegans will be used to introduce undergraduate students to the technology necessary to effectively use available databases. The Introductory Genetics course will be expanded to encompass new information from the Human Genome Project and to discuss ethical issues arising from that project.

AIDS /HIV neuropathy; methamphetamine; cerebrospinal fluid; drug abuse; biomarker; HIV infections; neurochemistry; macrophage inflammatory proteins; neurotoxins; cytokine receptors; tumor necrosis factor alpha; clinical research; human subject;

The biological, medical and social consequences of HIV infection of the central nervous system (CNS) include neurodegeneration, disability from neurocognitive disorders, increased mortality, and decreased quality of life. The CNS may serve as reservoir and sanctuary for HIV because the blood-brain barrier shields infection from certain immunologic and pharmacologic defenses. Recently, quantitative assays for HIV RNA and chemokines have been developed that promise to enhance our understanding of HIV neuropathogenesis and to facilitate the diagnosis and treatment of HIV CNS infection. This proposal outlines an integrated series of clinical and laboratory investigations to assess the role of the CNS in the development of antiretroviral (ARV) resistance and to evaluate strategies for therapeutic intervention in humans through the study of cerebrospinal fluid (CSF). Three clinical studies form the core of this 5-year proposal. Study 1A is an open-label trial of individualized combination ARV therapy (ART) for HIV neurocognitive disorder. The principal objective is to correlate improvements in neurocognitive function with CSF virologic (HIV RNA) suppression and CSF chemokine changes during ART. Eighty participants with neurocognitive disorders will be enrolled for a total of 155 treatment-observation periods of 12-weeks each. Study 1B is a controlled comparison with virologic responses in CSF and plasma with ART in individuals without neurocognitive disorders. Its main goal is to compare rates of change in CSF and plasma HIV RNA levels (HIV dynamics) and chemokines during ART, and to evaluate determinants of virologic efficacy and failure in the CSF. Fifty neurocognitively normal participants will be enrolled for 80 treatment-observation periods of 12- weeks each. Studies 1A and 1B have a parallel design in which participants are randomized to one of two treatment strategies (plasma versus plasma+CSF) based on the use of phenotypic ARV resistance testing. Study 2 compares virologic and immunologic (chemokine) responses in CSF and plasma during the withdrawal of antiretroviral treatment ("structured treatment interruption") in 2o subjects. Its goal is to determine the nature and extent of compartmentalization of CSF responses. Intensive laboratory investigations of HIV genetics , chemokines and chemokine receptors genotypes will be applied to the fluid samples derived from these studies. Performance of the work proposed here will benefit from this grant's relationship to the HIV Neurobehavioral Research Center and to the infrastructure that the HNRC provides in neurocognitive assessment, participant recruitment, data management, statistics and tissue archiving.

AIDS /HIV neuropathy

[unreadable] DESCRIPTION (provided by applicant): HIV-1 causes neurocognitive and neurological disorders that represent a public health problem as they result in a substantial burden to patients living with HIV infection, their caregivers, and the healthcare system. A recent report suggests that clade C viruses may possess a reduced capacity for neuroinvasion because clade C isolates bear tat sequences coding for a variant Tat protein shown in vitro to be defective in monocyte chemotaxis as compared to clade B Tat. The defective Tat chemokine motif is hypothesized to be clade C-specific based on isolates from several countries and could explain the lower prevalence of HIV brain involvement reported in some of these countries. However, no study has directly compared neurocognitive function among individuals infected with HIV-1 clades C and B. Thus, lower reported rates of dementia in regions where clade C is prevalent may result from ascertainment bias, differential prevalence of co-infections or other factors. This application proposes to perform a cross-sectional comparison of the influence of HIV-1 clade on neurocognitive and neurological disorders in southern Brazil. UCSD investigators, who have extensive experience in NeuroAIDS clinical research, will support investigators in Curitiba, Parana, Brazil, who care for large numbers of patients infected with either clade C or B. In this setting, clade-specific effects can be compared while controlling for potential confounding factors such as ethnicity, sociodemographic characteristics, risk factors for HIV infection and co-infections. UCSD investigators will train and guide the administration and interpretation of the clinical assessment instruments, transfer technology to the Brazilian site. [unreadable] [unreadable]

[unreadable] DESCRIPTION (provided by applicant): This competing renewal of R01 MH58076 proposes a multi-center, randomized clinical trial to evaluate the efficacy of a CNS-targeted antiretroviral treatment (ART) strategy for individuals with HIV-associated neurocognitive impairment (HNCI). Although highly active antiretroviral therapy (HAART) has reduced the incidence of severe dementia and may improve neurocognitive function, individual patient responses are variable, and the prevalence of HNCI remains high. Because HNCI is a significant burden to persons living with HIV infection, caregivers, and the healthcare system, and because it often persists despite HAART, the development of effective treatment strategies is of great public health importance. Consensus ART guidelines provide no specific recommendations on the management of HNCI. Evidence from in vitro and in vivo experiments and uncontrolled human studies has failed to resolve controversy on whether antiretroviral drug (ARV) CNS penetration and cerebrospinal fluid (CSF) virologic suppression are clinically important. Finally, no randomized, controlled trials have compared the neurocognitive benefits of regimens with differing CNS penetration. The chemical profile of many ARVs currently in development suggests that their CNS penetration will be negligible. Thus data on CNS penetration will become increasingly important as new agents are added into the clinical armamentarium. The proposed trial design is based on findings from the current funding period of this grant. Briefly, among individuals with HNCI initiating new ART, those on more CNS penetrating regimens had greater CSF viral load (VL) reduction, and neurocognitive outcomes were better in those who achieved CSF virologic suppression. Patients eligible for the study will: 1) meet consensus diagnostic criteria for HNCI; and 2) be anticipating initiation of a new ART regimen. A total of 120 patients at 3 sites will be randomized 1:1 to receive a CNS-targeted (CNS-T) ART strategy versus a non-CNS-T (comparison) strategy. The primary outcome, an assessment of change in global neurocognitive performance on a reliable and well-validated test battery, will be evaluated at 16 weeks, with continued follow-up to 32 weeks. Secondary aims will be to compare CNS-T and non-CNS-T ART on measures of CSF and plasma HIV suppression, and to delineate the impact of CNS-T on specific domains of neurocognitive functioning and on activities of daily living. Additional assessments that address explanatory goals will include ARV pharmacokinetics in plasma and CSF, and ARV resistance assays on CSF viral isolates. Samples will be stored for future use in studies aimed to evaluate viral fitness, neuropathogenicity and compartmental evolution. The proposed clinical trial would provide the level of evidence needed to formulate ART guidelines specific to HNCI. [unreadable] [unreadable] [unreadable]

In the past twenty years, the fields of Evolutionary and Developmental Biology have been revolutionized by the discovery of regulatory genes that are conserved in all animals. These discoveries established the universal nature of many aspects of development, but also revealed profound differences in the developmental machinery. Thus, two crucial questions today are: (1) what aspects of these regulatory pathways can change to create new traits during evolution, and (2) how does the structure of these pathways influence the process of evolution?
Intellectual Merit: The best way to address these questions is by comparing regulatory pathways from closely related species. Sexual characteristics make ideal subjects, since they are among the most rapidly evolving traits, and of interest to many biologists. One of the most dramatic differences in sexual development occurs in the elegans group of nematodes, a clade within the genus Caenorhabditis that contains some species with self-fertile hermaphrodites, and others with normal females. Because C. elegans is a leading model for the study of sex-determination, a wealth of data exists that can aid in the study of mating systems in this group. Recent results suggest that hermaphroditism evolved independently in C. elegans and C. briggsae. To test this hypothesis, the regulation of hermaphroditism in these two species must be compared at the level of gene regulatory pathways. In addition, these regulatory pathways have to be compared with those operating in a closely related male/ female species.
Aim #1. In a pilot screen for mutations that prevent hermaphrodite development in C. briggsae, Dr. Ellis found a single allele of the glf-1 gene. These mutants reproduce as a male/ female population, so glf-1 is required for XX animals to become self-fertile hermaphrodites. Mutations like this one provide the key to understanding hermaphrodite development in C. briggsae, and comparing it with C. elegans. Thus, he will continue this screen to saturation, to find additional alleles of glf-1, and alleles of other genes that control hermaphrodite development. He will backcross each mutation, assign recessive alleles to complementation groups, map each gene, and analyze double mutants to see where each gene acts in the regulatory pathway.
Aim #2. The ancestor of these nematodes was probably a male/ female species. To learn how C. elegans and C. briggsae evolved self-fertile hermaphroditism, it is necessary to learn how sex-determination worked in this ancestor. Thus, this aim involves the genetic characterization of how tra-1, the key sex-determination gene in C. elegans, regulates germ cell fates in the male/ female species C. remanei. In addition, Dr. Ellis has produced XX C. remanei that make sperm and oocytes. Surprisingly, their sperm do not activate in vivo. He will study the requirements for sperm activation in these animals, to test the model that hermaphroditism required two steps to evolve: the production of XX sperm, and the activation of these sperm to allow self-fertilization.
Broader Impacts: Recruiting minority students into the Biological Sciences, and providing them with the background and training needed to excel, are as important in South Jersey as in any part of the country. However, despite the existence of the Rutgers-Camden and Rowan campuses, there are few local opportunities to expose talented Undergraduates to cutting-edge research. This proposal describes an innovative Summer Research program for Undergraduates that should address this problem. It features an intensive week of full-time lectures and computer exercises designed to bring the students up to speed in Classical, Molecular and Population genetics, with examples that focus on the interplay between human medicine and basic research on model organisms. The next ten weeks are devoted to research projects in one of the basic science or medical laboratories at the UMDNJ. Finally, the experience closes with workshops on presenting scientific research, and talks by each of the students.

One of the major scientific achievements of the 20th century was the fusion of Darwin's Theory of Evolution with the study of Population Genetics. This fusion made it possible to use mathematics to explain how traits like color change as a species adapts to new environments. However, to understand more dramatic transitions, the laws of Developmental Biology must also be considered.

This project uses methods from Genetics, Developmental and Evolutionary Biology to find out how one dramatic change occurred during evolution - the origin of a complex trait or the creation of self-fertile hermaphrodites in roundworms. Three factors make this an ideal problem to study: (1) self-fertility is a complex trait that involves independent changes in sexual development and in how sperm become active, (2) roundworms are the most common animals on earth, and many species infect plants, animals or humans, so their ability to evolve new ways to reproduce could significantly affect the environment, and (3) all of the tools of modern Genetics are available for use in the study of these animals.

The famous roundworm Caenorhabditis elegans produces self-fertile hermaphrodites, but is related to several other Caenorhabditis species that instead make females. This innovative project will focus on alterations in just two genetic pathways (one controlling germ cell fate and one controlling sperm activation) to determine if they are sufficient to transform XX females of into self-fertile hermaphrodites.

These studies will provide advanced training for graduate and undergraduate students. They should also reveal how the complex trait of self-fertility evolved in roundworms, which will advance Evolutionary Biology, and help explain how roundworms invade and adapt to new environments.

Advances in antiretroviral therapy have reduced but not eliminated mortality and neurologic morbidity related to HIV infection. The epidemic has been transformed into a chronic disease in which there is a dynamic equilibrium between mechanisms maintaining viral persistence and host immune strategies that, in combination with antiretroviral therapy, hold viral activity in check. Prospects for eradication or cure are many years or decades away. Looking toward the future, the HNRC perceives four general areas in which research needs are greatest. In the renewal period, the Neuromedical Core (NMC) will therefore develop and mature its research infrastructure to support studies addressing the themes of aging, acute and early HIV infection and clinical relevance. A common thread linking these three themes is genetics-both host and viral. The newly-organized NMC is made up of two cooperative units comprising common resources (equipment, supplies) and staff that interact on a daily basis: a Clinical Research Support Unit (CRSU); and a Laboratory, Pharmacology & Biomarker Unit (LPBU). Together these units will perform evaluations on all HIV+ subjects and HIV- controls, including those enrolled in pilot studies of the Developmental Core. The over-arching objectives of the Neuromedical Core (NMC) are to provide comprehensive clinical and laboratory evaluations, scientific consultation, and mentorship, training, and community education in NeuroAIDS. In the current funding period the NMC facilitated 70 research projects including observational cohort studies, clinical-pathological investigations, imaging studies, clinical trials and international research performed by collaborating investigators at UCSD and many other institutions. By assisting investigators in widely diverging disciplines at all levels of project development, from conceptualization of hypotheses to study implementation, analysis, interpretation and dissemination, the NMC encourages the application of multiple scientific perspectives and stimulates interdisciplinary collaboration and coordination. Through a variety of flexible mechanisms including face-to-face meetings and video teleconferences we will collaborate closely with the Neuroimaging, Neurobehavioral, Neurovirology, Neurobiology, Developmental and International Cores to further the HNRC's transdisciplinary aims.

DESCRIPTION (provided by applicant): HIV creates complex genetic populations within a host, and remains latent in a variety of cell types and tissues under antiretroviral therapy, representing a barrier to therapeutic cure. Yet little is known about the relative sizes of latent viral reservoirs in different tissues such as the central nervous system (CNS), and even less about exchange between viral subpopulations in different tissues over time. Deep sequencing technologies allow extensive sampling of these populations. Previous studies have been hampered by limited sampling of viral diversity in the CNS and because they studied only single or occasionally multiple, sparse time points. Designing workable viral eradication strategies will require a characterizing the CNS viral reservoir and its population dynamics with higher resolution. To address these gaps in knowledge, we will apply recently developed techniques, digital PCR (dPCR) and ultra deep sequencing (UDS), to quantify tissue reservoir size and the dynamics of viral subpopulations in archived, longitudinal samples of cerebrospinal fluid cells and supernatant and peripheral blood mononuclear cells and plasma. Here we will evaluate viral subpopulation interactions occurring after antiretroviral treatment interruption, which provides a substantial perturbation of steady state viral and cellular dynamics to anchor the observations. We will apply phylogenetic methods to viral population sequences from CNS and blood over time to assess population dynamics. The study sample comprises a unique, densely serially sampled group of 10 HIV+ subjects undergoing antiretroviral (ART) treatment interruption or viral rebound in the face of continued ART. The project will generate approximately 1.2 million viral sequences. These will be analyzed to delineate how the CNS viral reservoir interacts dynamically with other viral subpopulations and contributes to viral diversification and pathogenicity. The project also will measure the size of CNS viral reservoirs. After de-identification of human subjects, viral sequences will be posted as appropriate on public scientific data resource utilities and software generated for this project will be made publicly available.

DESCRIPTION (provided by applicant): A critical barrier to progress in multidisciplinary clinical research on HIV and aging is the paucity in clinical studies to date of truly older HIV-infected (HIV+) individuals - those in whom the synergistic effects of HIV and age on brain structure and function are most likely to be observed. Although HIV+ people in the U.S. are now living into old age with long-term combination antiretroviral treatment (CART) and the U.S. CDC estimates that by 2015 more than 10% of all HIV+ individuals will exceed 65 years of age (i.e., older HIV+), very few such individuals have actually been included in published reports. We propose to capitalize on a unique geographic concentration of HIV+ individuals over age 65 in a cluster of desert communities nearby to San Diego, where their proportion has already exceeded 10%. We will establish a productive, collaborative partnership between the aging HIV+ community in Riverside County and the multidisciplinary UCSD HIV Neurobehavioral Research Center (HNRC) to investigate neurological functioning among older HIV+ individuals. We will strengthen and evolve an emerging alliance between desert community activists and HNRC researchers. We will leverage the well- established, NIMH-funded HNRC infrastructure to establish this new cohort with modest support. We will demonstrate feasibility by training local personnel in high-quality clinical research evaluations and by establishing an initial cohort of 20 well-characterized older HIV+ persons. These preliminary efforts will support the establishment of an expanded clinical research infrastructure for planned future studies on interventions to maximize neurological health, productivity and quality of life in the oldest old HIV+ persons.

? DESCRIPTION: HIV-associated neurocognitive disorders (HAND) affect 30-50% of HIV+ individuals, including those with virologic suppression on combination antiretroviral therapy (cART), and are disproportionately common in older individuals. Neurocognitive impairment in HIV is a source of disability not only in itself, but also because it magnifies impediments due to other HIV-associated non-AIDS (HANA) conditions by interfering with individuals' abilities to effectively implement personal and therapeutic compensatory strategies. Despite this, there is currently no effective treatment. Here we propose to address this need by combining a novel biomedical treatment, tesamorelin, and a state-of-the-art behavioral intervention, 2-way texting, to maximize adherence to study drug. Our preliminary data indicate that abdominal obesity (a marker of visceral adiposity), systemic inflammation, and immune activation are closely linked to HAND. The biomedical treatment will be a randomized, double-masked, placebo-controlled phase II clinical trial of tesamorelin (Tes), a GHRH analogue that reduces visceral adiposity, inflammation and immune activation. Tes has also been shown to increase IGF-1, which promotes brain angiogenesis, neurite outgrowth and synaptogenesis. Inclusion criteria will be HIV+, aged 40-70 years on stable cART for at least 12 weeks with undetectable viral load, with abdominal obesity and potentially reversible HAND. Exclusions will be individuals not meeting criteria for HAND based on published research diagnostic criteria (Antinori et al, 2007) as well as those with diabetes mellitus or hepatitis C coinfection. A total of 140 subjects will be enrolle at UCSD and USC and randomized 3:2 (tesamorelin:placebo) to achieve an evaluable sample of 106 subjects completing treatment for 9 months. We hypothesize that tesamorelin will improve the primary outcome of neurocognitive performance as measured by the global deficit score method. We will also evaluate secondary mechanistic outcomes as follows: 1) biomarkers of inflammation and monocyte activation, 2) brain magnetic resonance spectroscopy (MRS) evidence of cerebral inflammation and 3) MRI hippocampal volume increases. Multiple tools will be used to enhance adherence and combat treatment fatigue in this impaired population, including a state-of-the-art behavioral intervention comprising an adaptation of the individualized Texting for Adherence Building (iTAB) platform. Additional incentives to study participation will be provision of cell phones and data plans for text messaging, an open-label active study drug extension offered to all participants who complete the blinded placebo-controlled phase, and reimbursement for participant time and expense. By optimizing neurocognitive function, we endeavor to reduce the burden of disability in aging HIV-infected individuals on cART. Successful completion of this Phase II trial will lead to larger and longer duration Phase III studies to demonstrate efficacy.

NEUROASSESSMENT CORE PROJECT SUMMARY/ABSTRACT: The newly reorganized, streamlined NeuroAssessment Core (NAC) will have the overall goal of supporting comprehensive neuromedical, neurobehavioral and neuroimaging assessments for the characterization of HIV+ individuals and HIV- controls in HNRC-affiliated studies. The Core will comprise 3 integrated subunits: Neuromedical (NM), Neurobehavioral (NBh) and Neuroimaging (NI). We aim to facilitate and enhance multidisciplinary research in neuroAIDS by providing a range of services, training and scientific consultation to projects such as investigator-driven R01s and R21s, international neuroAIDS studies, and a variety of intra- and extramural investigations. Historically the Core and its investigators have been leaders in the field, spurring the development of new methods and adapting to the continually evolving scientific landscape. Consistent with this, the Core will provide resources to support the Center's new themes of HIV persistence and cure, and how the human gut microbiome interacts with HIV and its treatment to affect the CNS. Specific services relevant to HIV persistence and cure include serial lumbar punctures to evaluate viral rebound following HIV reservoir interventions, and high volume CSF collection and neurocognitive (NC) testing to assess effects of such interventions on brain functioning. The gut microbiome will be characterized by collecting and processing samples of stool. Standard evaluations will continue to include a structured neuromedical history, clinical and laboratory examinations, and establishment of diagnoses of central and peripheral neurological complications of HIV. The NAC's NI Unit will provide resources, including training, consultation, and technical support, for the detection and measurement of HIV- related brain injury using a broad array of techniques, including structural, functional, and metabolite MRI and PET imaging. This work will support investigations of the cognitive consequences and neuromedical correlates of these effects; the underlying pathological mechanisms that give rise to this damage; and potential biomarkers for treatment success. The NBh Unit will perform a comprehensive assessment of all participants in the HNRC cohort that will include well-validated measures of NC functioning, psychiatric status, and everyday functioning, in accordance with the HAND diagnostic guidelines. The NBh Unit's specific Resource Objectives are to provide: 1) demographically-adjusted individual, domain, and global summary scores of NC functioning; 2) Determinations of NC change in individual participants using reliable and validated actuarial methods; 3) Self-assessment and laboratory-based measures of everyday functioning; 4) Current and lifetime history of mood and substance use diagnoses; and 5) Technical assistance, training, certification, consultation, and career development mentoring. Data generated by the NAC range from NC performance and diagnostic formulations to ART information, disease staging and viral loads (VLs), to clinical laboratory measurements, medical histories, and physical examinations.

SUMMARY/ABSTRACT HIV-associated neuropathic pain (HIV-NP) affects a significant proportion of people living with HIV (PLWH) and has a major impact on everyday functioning and quality of life in this population. Over the past decade a growing number of preclinical studies and clinical trials have indicated that cannabis administration and manipulation of the endocannabinoid (EC) system may have therapeutic utility in addressing HIV-NP. EC CB2 receptor activation and inhibition of the EC deactivation enzymes fatty acid amide hydrolase (FAAH) and monoacyglycerol lipase (MAGL) have been shown to decrease pain in rodent models of HIV-NP, while acute exposure to cannabis reduces self-reported pain in PLWH with neuropathy. However, little work has been conducted to elucidate the effects of the two primary cannabinoids (delta-9-tetrahydrocannabinol, THC and cannabidiol, CBD) on the EC system or to assess EC function in PLWH. The objective of this application is to address these fundamental gaps in our knowledge by: 1) examining the acute effect of administering NIDA- prepared THC/CBD products on HIV-NP; 2) utilizing mHealth text messaging to monitor daily real-world self- administered cannabis effects on pain; 3) assessing the relationship between cannabinoids and EC biomarkers, including ligands, enzymes, and receptor expression; and 4) conducting exploratory analyses to evaluate the effect of longitudinal cannabinoid use on changes in HIV-NP over time. We will examine the effect of low (0.20%), medium (1.3%), and high (13%) CBD-containing cannabis on NP, the EC system (ligands AEA and 2-AG, enzymes FAAH and MAGL, CB2 receptor expression), and heart rate variability (as a proposed objective biological measure of pain) in 120 PLWH who use cannabis to treat neuropathic pain. We will subsequently employ a mobile phone text messaging system, the Individual Monitoring of Pain And Cannabis Taken (IMPACT), to track cannabis exposure, CBD and THC consumption, and pain over a period of 6 months in these same PLWH participants. IMPACT will be used quantify the real-time effects of acute CBD/THC exposure on pain before and after cannabis self-administration, the real-time relationship between self- reported pain and changes in HRV, and to assess any longitudinal changes in NP, HIV clinical outcomes (viral load, CD4) and cognition during the 6-month period. This plan allows us to acquire data and compare the effects of cannabis product obtained from NIDA and self-administered cannabis obtained from local medicinal dispensaries. The overarching hypothesis is that CBD exposure and a higher CBD/THC ratio will exert beneficial effects both in the laboratory and during the observational study, including increasing EC biomarkers and reducing NP. In summary, this approach will advance our understanding about several key issues, including the interaction between cannabis constituents, the EC system and pain, the biological mechanisms that underlie these effects (EC enzymes, receptor), and the longer-term effects of cannabis use on health- related outcomes in HIV, including predictors of mortality (HRV, CD4, viral load) and neurocognition.

Central nervous system (CNS) complications are common among people with HIV (PWH), even those who are taking antiretroviral therapy (ART). The spectrum of CNS complications is broad, ranging from mild cognitive deficits that do not affect daily functioning to life-threatening encephalitis. Cognitive and mood disorders are among the most common CNS diseases that affect PWH and share a common risk factor, inflammation. Inflammation persists in effectively treated PWH for multiple reasons, including production of HIV RNA and proteins and gut dysbiosis and microbial translocation. CHARTER is a multisite, U.S.-based, neuroHIV cohort study that is funded by NIH and that has investigated CNS disorders in PWH for nearly two decades, during which it has completed more than 6,000 assessments generating more than 10 million data points. CHARTER has made important contributions to understanding the frequency, risk factors, and pathogenesis of these disorders. In recent years, new questions have arisen about the heterogeneity, biological basis, clinical impact, and management of CNS disorders. This debate has highlighted the need to create new classifications of CNS disorders in PWH that are more biology-based. We propose to use methods such as machine learning and an agnostic approach to categorize CHARTER?s high-dimensional neurobehavioral, neuromedical, psychiatric, substance use, and imaging data. Such analyses would yield not just cognitive phenotypes but biopsychosocial (BPS) phenotypes that could identify new mechanisms that lead to clinically useful diagnostic tests, new therapies, and better management of CNS disorders in PWH. Our overarching goal is to leverage prior investment in CHARTER by using its data and stored specimens to a) better understand cognitive and BPS phenotypes in PWH and b) relate them to biological mechanisms. To accomplish this, we will use unsupervised and supervised machine learning methods to analyze data from CHARTER?s comprehensive assessments with the goal of identifying new cognitive and BPS phenotypes (Aim 1). We will then compare these new phenotypes to high-dimensional data from CHARTER?s completed genomewide association study as well as new data we will generate on inflammation (45-plex bead-based array) and highly novel assays of the microbiome and the metabolome in blood and CSF (Aim 2). Our analyses will include a specific focus how sex affects the observed relationships. To determine if this novel approach relates more strongly to biology than prior methods, we will also compare the performance of the new phenotypes to those defined by the 2007 HAND criteria. This highly innovative application is supported by strong preliminary data, responds well to Office of AIDS Research priorities, and will address key gaps in the field, including the need to better understand the pathogenesis of comorbid disease.