scholarly journals Enrichment of the HIV reservoir in CD32+ CD4 T cells occurs early in blood and tissue

2017 ◽  
Author(s):  
Genevieve E Martin ◽  
Matthew Pace ◽  
John P Thornhill ◽  
Chansavath Phetsouphanh ◽  
Jodi Meyerowitz ◽  
...  

AbstractThe Fc receptor CD32 has been proposed as a marker for CD4 T cells latently infected with HIV. We demonstrate that enrichment for HIV DNA in CD32+ CD4 T cells can be found early in infection in both tissue and blood. However, we find no evidence for a correlation between CD32 expression on CD4 T cells and either HIV DNA levels or time to rebound viraemia following treatment interruption. CD32+ CD4 T cells have a more differentiated memory phenotype, and high levels of expression of immune checkpoint receptors PD-1, Tim-3 and TIGIT as well as the activation marker, HLA DR. There was no difference in the phenotype or frequency of CD32 expressing cells prior to or after the initiation of antiretroviral therapy, or compared with healthy controls, suggesting that preferential infection or survival, rather than up-regulation, may be responsible for the observed enrichment of proviral HIV DNA in CD32+ CD4 T cells.

Blood ◽  
2013 ◽  
Vol 121 (21) ◽  
pp. 4321-4329 ◽  
Author(s):  
Claire Vandergeeten ◽  
Rémi Fromentin ◽  
Sandrina DaFonseca ◽  
Mariam B. Lawani ◽  
Irini Sereti ◽  
...  

Key Points IL-7 does not disrupt viral latency in highly pure resting latently infected CD4+ T cells from HIV-infected subjects receiving ART. IL-7 therapy leads to a 70% increase in the absolute number of circulating CD4+ T cells harboring integrated HIV DNA 4 weeks posttherapy.


Author(s):  
Ali Mosayebian ◽  
Zohreh Koohini ◽  
Hadi Hossein-Nataj ◽  
Saeid Abediankenari ◽  
Siavash Abedi ◽  
...  

Asthma is a chronic disorder of the airways characterized by reversible airflow obstruction, inflammation and bronchial hyperresponsiveness. Different immune cells and molecules have been attributed to involve in pathogenesis of asthma. In the current case-control study, the expression of T cell Ig and mucin domain-containing molecule-3 (Tim-3) and programmed death-1 (PD-1) was studied on CD4+ T cells of patients with asthma and normal controls. The frequency of Tim-3+/PD-1+/CD4+ T cells was determined by a three color flow cytometry method in 37 patients with asthma and 32 healthy controls. To evaluate the Th1/Th2 ratio, peripheral blood mononuclear cells were isolated from all samples and stimulated with phorbol 12- myristate 13- acetate (PMA)/ionomycin for 18 h. IFN-γ and Interleukin-4 (IL-4) were measured in culture supernatants by ELISA. Serum total immunoglobulin E (IgE) was also measured in all samples. Significant increase in percentage and absolute count of Tim-3+/PD-1+/CD4+, Tim-3+/CD4+ and PD-1+/CD4+ T cells was found in asthmatic patients compared to healthy controls (p=0.02, p<0.0001 and p=0.01, respectively). The IFN-γ/IL-4 ratio (Th1/Th2 ratio) was significantly higher in healthy controls than that of asthmatic patients (p=0.029). Our data regarding the increased expression of PD-1 and Tim-3 on CD4+ T cells of patients with asthma suggest the potential roles of these immune checkpoint receptors in immune dys-regulation of asthma.


2012 ◽  
Vol 86 (9) ◽  
pp. 5390-5392 ◽  
Author(s):  
J. Blazkova ◽  
D. Murray ◽  
J. S. Justement ◽  
E. K. Funk ◽  
A. K. Nelson ◽  
...  

2019 ◽  
Vol 93 (15) ◽  
Author(s):  
Celina M. Abreu ◽  
Rebecca T. Veenhuis ◽  
Claudia R. Avalos ◽  
Shelby Graham ◽  
Suzanne E. Queen ◽  
...  

ABSTRACTUnderstanding the cellular and anatomical sites of latent virus that contribute to human immunodeficiency virus (HIV) rebound is essential for eradication. In HIV-positive patients, CD4+T lymphocytes comprise a well-defined functional latent reservoir, defined as cells containing transcriptionally silent genomes able to produce infectious virus once reactivated. However, the persistence of infectious latent virus in CD4+T cells in compartments other than blood and lymph nodes is unclear. Macrophages (Mϕ) are infected by HIV/simian immunodeficiency virus (SIV) and are likely to carry latent viral genomes during antiretroviral therapy (ART), contributing to the reservoir. Currently, the gold standard assay used to measure reservoirs containing replication-competent virus is the quantitative viral outgrowth assay (QVOA). Using an SIV-macaque model, the CD4+T cell and Mϕ functional latent reservoirs were measured in various tissues using cell-specific QVOAs. Our results showed that blood, spleen, and lung in the majority of suppressed animals contain latently infected Mϕs. Surprisingly, the numbers of CD4+T cells, monocytes, and Mϕs carrying infectious genomes in blood and spleen were at comparable frequencies (∼1 infected cell per million). We also demonstrate thatex vivoviruses produced in the Mϕ QVOA are capable of infecting activated CD4+T cells. These results strongly suggest that latently infected tissue Mϕs can reestablish productive infection upon treatment interruption. This study provides the first comparison of CD4+T cell and Mϕ functional reservoirs in a macaque model. It is the first confirmation of the persistence of latent genomes in monocytes in blood and Mϕs in the spleen and lung of SIV-infected ART-suppressed macaques. Our results demonstrate that transcriptionally silent genomes in Mϕs can contribute to viral rebound after ART interruption and should be considered in future HIV cure strategies.IMPORTANCEThis study suggests that CD4+T cells found throughout tissues in the body can contain replication-competent SIV and contribute to rebound of the virus after treatment interruption. In addition, this study demonstrates that macrophages in tissues are another cellular reservoir for SIV and may contribute to viral rebound after treatment interruption. This new insight into the size and location of the SIV reservoir could have great implications for HIV-infected individuals and should be taken into consideration for the development of future HIV cure strategies.


AIDS ◽  
2016 ◽  
Vol 30 (10) ◽  
pp. 1511-1520 ◽  
Author(s):  
Gabriela Khoury ◽  
Jenny L. Anderson ◽  
Rémi Fromentin ◽  
Wendy Hartogenesis ◽  
Miranda Z. Smith ◽  
...  

2021 ◽  
Author(s):  
Jeffrey Kuniholm ◽  
Elise Armstrong ◽  
Brandy Bernabe ◽  
Carolyn Coote ◽  
Anna Berenson ◽  
...  

ABSTRACTHIV-establishes a persistent proviral reservoir by integrating into the genome of infected host cells. Current antiretroviral treatments do not target this persistent population of proviruses which include latently infected cells that upon treatment interruption can be reactivated to contribute to HIV-1 rebound. Deep sequencing of persistent HIV proviruses has revealed that greater than 90% of integrated HIV genomes are defective and unable to produce infectious virions. We hypothesized that intragenic elements in the HIV genome support transcription of aberrant HIV-1 RNAs from defective proviruses that lack long terminal repeats (LTRs). Using an intact provirus detection assay, we observed that resting CD4+ T cells and monocyte-derived macrophages (MDMs) are biased towards generating defective HIV-1 proviruses. Multiplex reverse transcription digital drop PCR identified Env and Nef transcripts which lacked 5’ untranslated regions (UTR) in acutely infected CD4+ T cells and MDMs indicating transcripts are generated that do not utilize the promoter within the LTR. 5’UTR-deficient Env transcripts were also identified in a cohort of people living with HIV (PLWH) on ART, suggesting that these aberrant RNAs are produced in vivo. Using 5’ rapid amplification of cDNA ends (RACE), we mapped the start site of these transcripts within the Env gene. This region bound several cellular transcription factors and functioned as a transcriptional regulatory element that could support transcription and translation of downstream HIV-1 RNAs. These studies provide mechanistic insights into how defective HIV-1 proviruses are persistently expressed to potentially drive inflammation in PLWH.Author SummaryPeople living with HIV establish a persistent reservoir which includes latently infected cells that fuel viral rebound upon treatment interruption. However, the majority of HIV-1 genomes in these persistently infected cells are defective. Whether these defective HIV genomes are expressed and whether they contribute to HIV associated diseases including accelerated aging, neurodegenerative symptoms, and cardiovascular diseases are still outstanding questions. In this paper, we demonstrate that acute infection of macrophages and resting T cells is biased towards generating defective viruses which are expressed by DNA regulatory elements in the HIV genome. These studies describe an alternative mechanism for chronic expression of HIV genomes.


2020 ◽  
Author(s):  
Florencia A. T. Boshier ◽  
Daniel B. Reeves ◽  
Elizabeth R. Duke ◽  
David A. Swan ◽  
Martin Prlic ◽  
...  

AbstractThe HIV reservoir is a population of 1-10 million anatomically dispersed, latently infected memory CD4+ T cells in which an HIV DNA molecule is quiescently integrated into human chromosomal DNA. When antiretroviral therapy (ART) is stopped and HIV replication initiates in one of these cells, systemic viral spread resumes, rekindling progression to AIDS. Therefore, HIV latency prevents cure. The HIV reservoir contains clones: identical HIV sequences that are integrated within identical human chromosomal DNA locations. The presence of these clones demonstrates that proliferation of CD4+ T cells sustains infection despite ART. The reservoir has a precise structure consisting of a small number of large clones and a large number of small clones. However, the mechanisms leading to this structure have not been identified. We developed a mathematical model that recapitulates the profound depletion and brisk recovery of CD4+ T cells, reservoir creation, and viral load trajectory during primary HIV infection. We extended the model to simulate stochastically individual HIV reservoir clones and identified that uneven proliferation among clones during recovery from CD4+ lymphopaenia is sufficient to explain the observed clonal reservoir distribution. We project that within one month of infection 75-95% of reservoir cells are generated from cellular proliferation rather than denovo viral infection. Recent detection of HIV infected clones during the first 5 weeks of infection support our model’s predictions.


1998 ◽  
Vol 188 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Tae-Wook Chun ◽  
Delphine Engel ◽  
Stephanie B. Mizell ◽  
Linda A. Ehler ◽  
Anthony S. Fauci

Although it has been demonstrated that certain cytokines, particularly proinflammatory cytokines, can enhance ongoing viral replication in peripheral blood mononuclear cells (PBMCs) of HIV-1–infected individuals, it is unclear what role these cytokines play in the induction of HIV-1 replication in latently infected, resting CD4+ T cells. This study demonstrates that the in vitro combination of the proinflammatory cytokines interleukin (IL)-6 and tumor necrosis factor (TNF)-α together with the immunoregulatory cytokine IL-2 are potent inducers of viral replication in highly purified, latently infected, resting CD4+ T cells derived from HIV-infected individuals who are antiretroviral therapy–naive as well as those who are receiving highly active antiretroviral therapy (HAART). Viral replication induced by this combination of cytokines was completely suppressed in the presence of HAART in vitro. Given that an array of cytokines, including IL-6, TNF-α, and IL-2, are copiously expressed in the microenvironment of the lymphoid tissues, which harbor the latent viral reservoirs, induction of HIV by this combination of cytokines may in part explain the commonly observed reappearance of detectable plasma viremia in HIV-infected individuals in whom HAART was discontinued. Moreover, since it is likely that these infected cells die upon activation of virus and that HAART prevents spread of virus to adjacent cells, the observation that this combination of cytokines can markedly induce viral replication in this reservoir may have important implications for the activation-mediated diminution of the latent reservoir of HIV in patients receiving HAART.


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