Astrocytes are HIV reservoirs in the brain: A cell type with poor HIV infectivity and replication but efficient cell-to-cell viral transfer
Journal of neurochemistry
Valdebenito, S;Castellano, P;Ajasin, D;Eugenin, EA;
PMID: 33655498 | DOI: 10.1111/jnc.15336
The major barrier to eradicating Human immunodeficiency virus-1 (HIV) infection is the generation of tissue-associated quiescent long-lasting viral reservoirs refractory to therapy. Upon interruption of anti-retroviral therapy (ART), HIV replication can be reactivated. Within the brain, microglia/macrophages and a small population of astrocytes are infected with HIV. However, the role of astrocytes as a potential viral reservoir is becoming more recognized because of the improved detection and quantification of HIV viral reservoirs. In this report, we examined the infectivity of human primary astrocytes in vivo and in vitro, and their capacity to maintain HIV infection, become latently infected, be reactivated, and transfer new HIV virions into neighboring cells. Analysis of human brain tissue sections obtained from HIV-infected individuals under effective and prolonged ART indicates that a small population of astrocytes has integrated HIV-DNA. In vitro experiments using HIV-infected human primary astrocyte cultures confirmed a low percentage of astrocytes had integrated HIV-DNA, with poor to undetectable replication. Even in the absence of ART, long-term culture results in latency that could be transiently reactivated with histone deacetylase inhibitor, tumor necrosis factor-alpha (TNF-α), or methamphetamine. Reactivation resulted in poor viral production but efficient cell-to-cell viral transfer into cells that support high viral replication. Together, our data provide a new understanding of astrocytes' role as viral reservoirs within the central nervous system (CNS).
The active human immunodeficiency virus reservoir during antiretroviral therapy: emerging players in viral persistence
Current opinion in HIV and AIDS
Astorga-Gamaza, A;Buzon, MJ;
PMID: 33973900 | DOI: 10.1097/COH.0000000000000685
To discuss the role of CD4+ T cells with active Human immunodeficiency virus (HIV), meaning infected cells with transcriptional and/or translational viral activity during antiretroviral therapy (ART), focusing on new technologies for its detection, potential cell markers for its characterization, and evidences on the contribution of the active HIV reservoir to long-term viral persistence.HIV-infected cells expressing viral ribonucleic acid are systematically detected in subjects on long-term ART. In recent years, powerful new tools have provided significant insights into the nature, quantification, and identification of cells with active HIV, including the identification of new cell markers, and the presence of viral activity in specific cell populations located in different cellular and anatomical compartments. Moreover, studies on viral sequence integrity have identified cell clones with intact viral genomes and active viral transcription that could potentially persist for years. Together, new investigations support the notion that the active reservoir could represent a relevant fraction of long-term infected cells, and therefore, the study of its cell sources and mechanisms of maintenance could represent a significant advance in our understanding of viral persistence and the development of new curative strategies.The presence of HIV-infected cells with viral expression during ART has been traditionally overlooked for years. Based on recent investigations, this active viral reservoir could play an important role in HIV persistence.
Hobson, J;Gilstrap, S;Ho, M;Fehrmann, N;Gathright, J;White, D;Thomas, J;Goodin, B;Cody, S;
| DOI: 10.1016/j.jpain.2022.03.140
Emerging literature suggests that experiences of discrimination negatively influence health and well-being. It is unfortunately common for people living with HIV (PLWH) to be stigmatized and discriminated against because of their HIV status and other marginalized identities (e.g., ethnicity/race, sexual identity and orientation). To date, little research has specifically examined discrimination in PWLH and its associations with pain and other pain-relevant factors such as mood and sleep. The purpose of this ongoing study was to preliminarily analyze associations among daily experiences of discrimination, pain severity and interference, depressive symptoms, and sleep in PLWH. Participants included 24 PLWH recruited from a local HIV treatment center. Participants completed The Everyday Discrimination Scale (TEDS) followed by the Brief Pain Inventory - Short Form (BPI-SF), the Insomnia Severity Index (ISI), and the Center for Epidemiologic Studies - Depression Scale (CES-D). Initial findings tentatively suggest that more frequent daily experiences of discrimination may be significantly associated with greater pain interference on the BPI-SF (p = .030) and greater severity of insomnia symptoms on the ISI (p = .059). However, it appears that daily experiences of discrimination may not be meaningfully associated with pain severity on the BPI-SF (p = .401) or depressive symptoms on the CES-D (p = .235). Our findings highlight the potentially deleterious effects of daily discrimination experiences on pain and sleep in in PLWH. As this ongoing study recruits a larger sample of PLWH, data will need to be reanalyzed to better determine the durability of these preliminary findings. However, there is potential that findings from this study may assist in elucidating causal pathways linking discrimination to pain and pain relevant health behaviors like sleep in PLWH. Grant support from The Impact of Insomnia on Pain, Physical Function, and Inflammation in HIV (3R01HL147603-03S1).
Govindaraj, S;Babu, H;Sidharthan, SK;Vaccari, M;
| DOI: 10.3389/fimmu.2023.1203531
Currently, there are approximately 38.4 million individuals living with the Human Immunodeficiency Virus (HIV), of which 36.7 million adults, 1.7 million children (
Mavigner M, Habib J, Deleage C, Rosen E, Mattingly C, Bricker K, Kashuba A, Amblard F, Schinazi RF, Jean S, Cohen J, McGary C, Paiardini M, Wood MP, Sodora DL, Silvestri G, Estes J, Chahroudi A.
PMID: 29997216 | DOI: 10.1128/JVI.00562-18
Worldwide, nearly two million children are infected with HIV, with breastfeeding accounting for the majority of contemporary HIV transmissions. Antiretroviral therapy (ART) has reduced HIV-related morbidity and mortality but is not curative. The main barrier to a cure is persistence of latent HIV in long-lived reservoirs. However, our understanding of the cellular and anatomic sources of the HIV reservoir during infancy and childhood is limited. Here, we developed a pediatric model of ART suppression in orally SIV-infected rhesus macaque (RM) infants, with measurement of virus persistence in blood and tissues after 6-9 months of ART. Cross-sectional analyses were conducted to compare SIV RNA and DNA levels in adult and infant RMs naïve to treatment and on ART. We demonstrate efficient viral suppression following ART initiation in SIV-infected RM infants with sustained undetectable plasma viral loads in the setting of heterogeneous penetration of ART into lymphoid and gastrointestinal tissues and low drug levels in the brain. We further show reduction in SIV RNA and DNA on ART in lymphoid tissues of both infant and adult RMs, but stable (albeit low) levels of SIV RNA and DNA in the brains of viremic and ART-suppressed infants. Finally, we report a large contribution of naïve CD4+ T-cells to the total CD4 reservoir of SIV in blood and lymph nodes of ART-suppressed RM infants, that differs from what we show in adults. These results reveal important aspects of HIV/SIV persistence in infants and provide insight into strategic targets for cure interventions in a pediatric population.IMPORTANCE While antiretroviral therapy (ART) can reduce HIV replication, the virus cannot be eradicated from an infected individual and our incomplete understanding of HIV persistence in reservoirs greatly complicates the generation of a cure for HIV. Given the immaturity of the infant immune system, it is of critical importance to study HIV reservoirs specifically in this population. Here, we established a pediatric animal model to simulate breastfeeding transmission and study SIV reservoirs in rhesus macaques (RM) infants. Our study demonstrates that ART can be safely administered to infant RM for prolonged periods of time and efficiently controls viral replication in this model. SIV persistence was shown in blood and tissues with a similar anatomic distribution of SIV reservoirs in infant and adult RMs. However, in the peripheral blood and lymph nodes, a higher contribution of the naïve CD4+ T-cells to the SIV reservoir was observed in infants compared to adults.
Central Nervous System (CNS) Viral Seeding by Mature Monocytes and Potential Therapies To Reduce CNS Viral Reservoirs in the cART Era
León-Rivera, R;Veenstra, M;Donoso, M;Tell, E;Eugenin, EA;Morgello, S;Berman, JW;
PMID: 33727362 | DOI: 10.1128/mBio.03633-20
The human immunodeficiency virus (HIV) enters the central nervous system (CNS) within a few days after primary infection, establishing viral reservoirs that persist even with combined antiretroviral therapy (cART). We show that monocytes from people living with HIV (PLWH) on suppressive cART harboring integrated HIV, viral mRNA, and/or viral proteins preferentially transmigrate across the blood-brain barrier (BBB) to CCL2 and are significantly enriched post-transmigration, and even more highly enriched posttransmigration than T cells with similar properties. Using HIV-infected ART-treated mature monocytes cultured in vitro, we recapitulate these findings and demonstrate that HIV+ CD14+ CD16+ ART-treated monocytes also preferentially transmigrate. Cenicriviroc and anti-JAM-A and anti-ALCAM antibodies significantly and preferentially reduce/block transmigration of HIV+ CD14+ CD16+ ART-treated monocytes. These findings highlight the importance of monocytes in CNS HIV reservoirs and suggest targets to eliminate their formation and reseeding.IMPORTANCE We characterized mechanisms of CNS viral reservoir establishment/replenishment using peripheral blood mononuclear cells (PBMC) of PLWH on cART and propose therapeutic targets to reduce/block selective entry of cells harboring HIV (HIV+) into the CNS. Using DNA/RNAscope, we show that CD14+ CD16+ monocytes with integrated HIV, transcriptionally active, and/or with active viral replication from PBMC of PLWH prescribed cART and virally suppressed, selectively transmigrate across a human BBB model. This is the first study to our knowledge demonstrating that monocytes from PLWH with HIV disease for approximately 22 years and with long-term documented suppression can still carry virus into the CNS that has potential to be reactivated and infectious. This selective entry into the CNS-and likely other tissues-indicates a mechanism of reservoir formation/reseeding in the cART era. Using blocking studies, we propose CCR2, JAM-A, and ALCAM as targets on HIV+ CD14+ CD16+ monocytes to reduce and/or prevent CNS reservoir replenishment and to treat HAND and other HIV-associated comorbidities.
Byrnes, SJ;Angelovich, TA;Busman-Sahay, K;Cochrane, CR;Roche, M;Estes, JD;Churchill, MJ;
PMID: 36146803 | DOI: 10.3390/v14091997
Human Immunodeficiency virus (HIV)-associated neurocognitive disorders are a major burden for people living with HIV whose viremia is stably suppressed with antiretroviral therapy. The pathogenesis of disease is likely multifaceted, with contributions from viral reservoirs including the brain, chronic and systemic inflammation, and traditional risk factors including drug use. Elucidating the effects of each element on disease pathogenesis is near impossible in human clinical or ex vivo studies, facilitating the need for robust and accurate non-human primate models. In this review, we describe the major non-human primate models of neuroHIV infection, their use to study the acute, chronic, and virally suppressed infection of the brain, and novel therapies targeting brain reservoirs and inflammation.
Deleage C, Chan CN, Busman-Sahay K, Estes JD.
PMID: 29316956 | DOI: 10.1186/s12977-017-0387-9
The development of increasingly safe and effective antiretroviral treatments for human immunodeficiency virus (HIV) over the past several decades has led to vastly improved patient survival when treatment is available and affordable, an outcome that relies on uninterrupted adherence to combination antiretroviral therapy for life. Looking to the future, the discovery of an elusive 'cure' for HIV will necessitate highly sensitive methods for detecting, understanding, and eliminating viral reservoirs. Next-generation, in situ hybridization (ISH) approaches offer unique and complementary insights into viral reservoirs within their native tissue environments with a high degree of specificity and sensitivity. In this review, we will discuss how modern ISH techniques can be used, either alone or in conjunction with phenotypic characterization, to probe viral reservoir establishment and maintenance. In addition to focusing on how these techniques have already furthered our understanding of HIV reservoirs, we discuss potential avenues for how high-throughput, next-generation ISH may be applied. Finally, we will review how ISH could allow deeper phenotypic and contextual insights into HIV reservoir biology that should prove instrumental in moving the field closer to viral reservoir elimination needed for an 'HIV cure' to be realized.
Gut Innate Immunity and HIV Pathogenesis
Dillon, SM;Wilson, CC;
PMID: 33687703 | DOI: 10.1007/s11904-021-00544-3
In the gastro-intestinal tract, the complex network of multiple innate cell populations play critical roles not only as a first line of defense against invading pathogens and in driving adaptive immune responses but also in maintaining intestinal homeostasis. Here, we describe the roles of various innate immune cell populations in gut immunity and detail studies investigating the impact of acute and chronic HIV infection on these cell populations. Alterations in frequencies, phenotype and/or function of innate lymphoid cells, dendritic cells, macrophages, neutrophils, and innate-like T cells have been reported in people with HIV (PWH), with many of these features persisting despite anti-retroviral therapy and virological suppression. Dysregulated gut innate immunity in PWH is a feature of gut pathogenesis. A greater understanding of the mechanisms driving impairment in the multiple different gut innate immune cell populations and the downstream consequences of an altered innate immune response on host defense and gut homeostasis in PWH is needed to develop more effective HIV treatments and cure strategies.
Functional impairment of HIV-specific CD8+ T cells precedes aborted spontaneous control of viremia
Collins, DR;Urbach, JM;Racenet, ZJ;Arshad, U;Power, KA;Newman, RM;Mylvaganam, GH;Ly, NL;Lian, X;Rull, A;Rassadkina, Y;Yanez, AG;Peluso, MJ;Deeks, SG;Vidal, F;Lichterfeld, M;Yu, XG;Gaiha, GD;Allen, TM;Walker, BD;
PMID: 34496223 | DOI: 10.1016/j.immuni.2021.08.007
Spontaneous control of HIV infection has been repeatedly linked to antiviral CD8+ T cells but is not always permanent. To address mechanisms of durable and aborted control of viremia, we evaluated immunologic and virologic parameters longitudinally among 34 HIV-infected subjects with differential outcomes. Despite sustained recognition of autologous virus, HIV-specific proliferative and cytolytic T cell effector functions became selectively and intrinsically impaired prior to aborted control. Longitudinal transcriptomic profiling of functionally impaired HIV-specific CD8+ T cells revealed altered expression of genes related to activation, cytokine-mediated signaling, and cell cycle regulation, including increased expression of the antiproliferative transcription factor KLF2 but not of genes associated with canonical exhaustion. Lymphoid HIV-specific CD8+ T cells also exhibited poor functionality during aborted control relative to durable control. Our results identify selective functional impairment of HIV-specific CD8+ T cells as prognostic of impending aborted HIV control, with implications for clinical monitoring and immunotherapeutic strategies.
Ma ZM, Dutra J, Fritts L, Miller CJ.
PMID: 26865706 | DOI: -
Abstract
The human immunodeficiency virus (HIV) is primarily transmitted by heterosexual contact and approximately equal numbers of men and women are infected with the virus worldwide. Understanding the biology of HIV acquisition and dissemination in men exposed to the virus by insertive penile intercourse is likely to help with the rational design of vaccines that can limit or prevent HIV transmission. To characterize the target cells and dissemination pathways involved in establishing systemic SIV infection, we necropsied male rhesus macaques at 1, 3, 7 and 14 days after penile SIV inoculation and quantified the levels unspliced SIV RNA and spliced SIV RNA in tissue lysates and the number of SIV RNA+ cells in tissues sections. We found that penile (glans, foreskin, coronal sulcus) T cells, and, to a lesser extent, macrophages and dendritic cells are primary targets of infection and that SIV rapidly reaches the regional lymph nodes. Seven days after inoculation SIV had disseminated to the blood, systemic lymph nodes and mucosal lymphoid tissues. Further, at 7 days post-inoculation (PI), spliced SIV RNA levels are highest in the genital lymph nodes indicating that this is the site where the infection is initially amplified. By 14 days PI spliced SIV RNA levels were high in all tissues, but they were highest in the gastrointestinal tract indicating that the primary site of virus replication had shifted from the genital lymph nodes to the gut. The stepwise pattern of virus replication and dissemination described here suggests that vaccine-elicited immune responses in the genital lymph nodes could help prevent the infection after penile SIV challenge.
IMPORTANCE:
To be most effective, vaccines should produce anti-viral immune responses in the anatomic sites of virus replication. Thus understanding the path taken by HIV from the mucosal surfaces, that are the site of virus exposure, to the deeper tissues where the virus replicates will provide insight into where AIDS vaccines should produce immunity to be most effective. In this study we determined that, by day 7 after penile inoculation, SIV has moved first to the inguinal lymph nodes and replicates to high levels. Although the virus is widely disseminated to other tissues by day 7, replication is largely limited to the inguinal lymph nodes. The step-by-step movement of SIV from penile mucosal surfaces to the draining lymph nodes may allow a HIV vaccine that produces immunity in these lymph nodes to block HIV from establishing an infection in an exposed person.
ORAL SECONDARY SYPHILIS IN PEOPLE LIVING WITH HIV: A 16-YEAR EXPERIENCE IN MEXICO CITY
Oral Surgery, Oral Medicine, Oral Pathology and Oral Radiology
Anaya-Saavedra, G;Castillejos-García, I;Maldonado-Mendoza, J;Ramírez-Amador, V;
| DOI: 10.1016/j.oooo.2021.03.041
Background The increase in syphilis rates worldwide, particularly in people living with HIV (PLWH), as well as the challenging diagnosis that secondary syphilis represents, make essential the accurate recognition of its manifestations, particularly in easy-access sites like the oral mucosa. Objective To describe the clinicopathologic spectrum of oral secondary syphilis (OSS) in PLWH. Methods A cross-sectional and descriptive study that included PLWH with OSS from 3 HIV referral centers in Mexico City (2004-2020). Demographic and clinical data were obtained. A comprehensive oral examination was done. OSS was diagnosed following established criteria. Histopathologic/cytological procedures were performed to rule out specific oral lesions. In all patients, Venereal Disease Research Laboratory tests were assessed and, if possible, a confirmatory fluorescent treponemal antibody test or biopsy was performed. Statistical analysis was performed using SPSS v25. Results Forty-seven PLWH with OSS (97.8% male, median age: 32 years, 63.8% with acquired immunodeficiency syndrome) were included. Thirty-five were receiving combination antiretroviral therapy (74.5%; median of 1146 [Q1-Q3: 337.5-1971] days) with a median CD4+ count of 385 (Q1-Q3: 223-664) cells/mm3 and a Log10 HIV viral load of 4.1 (Q1-Q3: 3.7-5.3) copies/mL. Forty had a complete clinical-serological diagnosis (85.1%; 17 had histopathologic confirmation) and 7 had a clinical-histopathologic diagnosis. Twenty-nine individuals presented 1 lesion (61.7%), and mucous patch was the most common type mainly on oropharyngeal mucosa, followed by ulcers and macular lesions. Ten patients presented maculopapular dermatosis (21.3%). Conclusions In PLWH, oral lesions, particularly mucous patch and/or ulcers on the oral and oropharyngeal mucosa, must alert specialists to consider a diagnosis of syphilis and perform a comprehensive panel of confirmatory tests.