scholarly journals Longitudinal Examination of the Intestinal Lamina Propria Cellular Compartment of Simian Immunodeficiency Virus-Infected Rhesus Macaques Provides Broader and Deeper Insights into the Link between Aberrant MicroRNA Expression and Persistent Immune Activation

2016 ◽  
Vol 90 (10) ◽  
pp. 5003-5019 ◽  
Author(s):  
Vinay Kumar ◽  
Workineh Torben ◽  
Carys S. Kenway ◽  
Faith R. Schiro ◽  
Mahesh Mohan
Keyword(s):  
T Cell ◽  
Lamina Propria ◽  
T Cell Activation ◽  
Immune Activation ◽  
Cell Activation ◽  
Critical Role ◽  
Intestinal Lamina Propria ◽  
Immunodeficiency Virus ◽  
Siv Infection

ABSTRACTChronic immune activation/inflammation driven by factors like microbial translocation is a key determinant of human immunodeficiency virus/simian immunodeficiency virus (HIV/SIV) disease progression. Although extensive research on inflammation has focused on studying protein regulators, increasing evidence suggests a critical role for microRNAs (miRNAs) in regulating several aspects of the immune/inflammatory response and immune cell proliferation, differentiation, and activation. To understand their immunoregulatory role, we profiled miRNA expression sequentially in intestinal lamina propria leukocytes (LPLs) of eight macaques before and at 21, 90, and 180 days postinfection (dpi). At 21 dpi, ∼20 and 9 miRNAs were up- and downregulated, respectively. However, at 90 dpi (n= 60) and 180 dpi (n= 44), ≥75% of miRNAs showed decreased expression. Notably, the T-cell activation-associated miR-15b, miR-142-3p, miR-142-5p, and miR-150 expression was significantly downregulated at 90 and 180 dpi. Out of ∼10 downregulated miRNAs predicted to regulate CD69, we confirmed miR-92a to directly target CD69. Interestingly, the SIV-induced miR-190b expression was elevated at all time points. Additionally, elevated lipopolysaccharide (LPS)-responsive miR-146b-5p expression at 180 dpi was confirmed in primary intestinal macrophages following LPS treatmentin vitro. Further, reporter and overexpression assays validated IRAK1 (interleukin-1 receptor 1 kinase) as a direct miR-150 target. Furthermore, IRAK1 protein levels were markedly elevated in intestinal LPLs and epithelium. Finally, blockade of CD8+T-cell activation/proliferation with delta-9 tetrahydrocannabinol (Δ9-THC) significantly prevented miR-150 downregulation and IRAK1 upregulation. Our findings suggest that miR-150 downregulation during T-cell activation disrupts the translational control of IRAK1, facilitating persistent gastrointestinal (GI) inflammation. Finally, the ability of Δ9-THC to block the miR-150-IRAK1 regulatory cascade highlights the potential of cannabinoids to inhibit persistent inflammation/immune activation in HIV/SIV infection.IMPORTANCEPersistent GI tract disease/inflammation is a cardinal feature of HIV/SIV infection. Increasing evidence points to a critical role for miRNAs in controlling several aspects of the immune/inflammatory response. Here, we show significant dysregulation of miRNA expression exclusively in the intestinal lamina propria cellular compartment through the course of SIV infection. Specifically, the study identified miRNA signatures associated with key pathogenic events, such as viral replication, T-cell activation, and microbial translocation. The T-cell-enriched miR-150 showed significant downregulation throughout SIV infection and was confirmed to target IRAK1, a critical signal-transducing component of the IL-1 receptor and TLR signaling pathways. Reduced miR-150 expression was associated with markedly elevated IRAK1 expression in the intestines of chronically SIV-infected macaques. Finally, Δ9-THC-mediated blockade of CD8+T-cell activationin vitrosignificantly inhibited miR-150 downregulation and IRAK1 upregulation, suggesting its potential for targeted immune modulation in HIV infection.

scholarly journals PAH- and PCB-induced Alterations of Protein Tyrosine Kinase and Cytokine Gene Transcription in Harbor Seal (Phoca Vitulina) PBMC

2005 ◽  
Vol 12 (2) ◽  
pp. 91-97 ◽  
Author(s):  
Jennifer C. C. Neale ◽  
Thomas P. Kenny ◽  
Ronald S. Tjeerdema ◽  
M. Eric Gershwin
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Tyrosine Kinases ◽  
Cell Activation ◽  
Critical Role ◽  
Harbor Seal ◽  
Lymphocyte Function ◽  
Altered Expression ◽  
Protein Tyrosine

Mechanisms underlyingin vitroimmunomodulatory effects of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) were investigated in harbor seal peripheral leukocytes, via real-time PCR. We examined the relative genetic expression of the protein tyrosine kinases (PTKs)FynandItk, which play a critical role in T cell activation, and IL-2, a cytokine of central importance in initiating adaptive immune responses. IL-1, the macrophage-derived pro-inflammatory cytokine of innate immunity, was also included as a measure of macrophage function. Harbor seal PBMC were exposed to the prototypic immunotoxic PAH benzo[a]pyrene (BaP), 3,3',4,4',5,5'-hexachlorobiphenyl (CB-169), a model immunotoxic PCB, or DMSO (vehicle control). Exposure of Con A-stimulated harbor seal PBMC to both BaP and CB-169 produced significantly altered expression in all four targets relative to vehicle controls. The PTKsFynandItkwere both up-regulated following exposure to BaP and CB-169. In contrast, transcripts for IL-2 and IL-1 were decreased relative to controls by both treatments. Our findings are consistent with those of previous researchers working with human and rodent systems and support a hypothesis of contaminant-altered lymphocyte function mediated (at least in part) by disruption of T cell receptor (TCR) signaling and cytokine production.

scholarly journals Loss of a Tyrosine-Dependent Trafficking Motif in the Simian Immunodeficiency Virus Envelope Cytoplasmic Tail Spares Mucosal CD4 Cells but Does Not Prevent Disease Progression

2012 ◽  
Vol 87 (3) ◽  
pp. 1528-1543 ◽  
Author(s):  
Matthew W. Breed ◽  
Andrea P. O. Jordan ◽  
Pyone P. Aye ◽  
Cornelis F. Lichtveld ◽  
Cecily C. Midkiff ◽  
...  
Keyword(s):  
T Cells ◽  
Disease Progression ◽  
Simian Immunodeficiency Virus ◽  
Lamina Propria ◽  
T Cell Activation ◽  
Immune Activation ◽  
Cell Activation ◽  
Cytoplasmic Tail ◽  
Microbial Translocation ◽  
Immunodeficiency Virus

ABSTRACTA hallmark of pathogenic simian immunodeficiency virus (SIV) and human immunodeficiency virus (HIV) infections is the rapid and near-complete depletion of mucosal CD4+T lymphocytes from the gastrointestinal tract. Loss of these cells and disruption of epithelial barrier function are associated with microbial translocation, which has been proposed to drive chronic systemic immune activation and disease progression. Here, we evaluate in rhesus macaques a novel attenuated variant of pathogenic SIVmac239, termed ΔGY, which contains a deletion of a Tyr and a proximal Gly from a highly conserved YxxØ trafficking motif in the envelope cytoplasmic tail. Compared to SIVmac239, ΔGY established a comparable acute peak of viremia but only transiently infected lamina propria and caused little or no acute depletion of mucosal CD4+T cells and no detectable microbial translocation. Nonetheless, these animals developed T-cell activation and declining peripheral blood CD4+T cells and ultimately progressed with clinical or pathological features of AIDS. ΔGY-infected animals also showed no infection of macrophages or central nervous system tissues even in late-stage disease. Although the ΔGY mutation persisted, novel mutations evolved, including the formation of new YxxØ motifs in two of four animals. These findings indicate that disruption of this trafficking motif by the ΔGY mutation leads to a striking alteration in anatomic distribution of virus with sparing of lamina propria and a lack of microbial translocation. Because these animals exhibited wild-type levels of acute viremia and immune activation, our findings indicate that these pathological events are dissociable and that immune activation unrelated to gut damage can be sufficient for the development of AIDS.

scholarly journals The importance of nef in the induction of human immunodeficiency virus type 1 replication from primary quiescent CD4 lymphocytes.

1994 ◽  
Vol 179 (1) ◽  
pp. 115-123 ◽  
Author(s):  
C A Spina ◽  
T J Kwoh ◽  
M Y Chowers ◽  
J C Guatelli ◽  
D D Richman
Keyword(s):  
T Cell ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cell Model ◽  
Cd4 Cells ◽  
Immunodeficiency Virus ◽  
Hiv 1 ◽  
Cd4 Lymphocytes

The viral regulatory gene, nef, is unique to the human immunodeficiency viruses (HIV) and their related primate lentiviruses. Expression of the nef gene has been shown to be essential to the maintenance of high levels of virus replication and the development of pathogenesis in the animal model of simian immunodeficiency virus (SIV) infection. In contrast to this in vivo model, the use of standard T cell culture systems to study nef function in vitro has produced a spectrum of contradictory results, and has failed to demonstrate a significant positive influence of nef on viral life cycle. We have developed a cell model to study regulation of HIV-1 replication that we believe reflects more accurately virus-cell interactions as they occur in vivo. Our experimental system used acute virus infection of purified, quiescent CD4 lymphocytes and subsequent induction of viral replication through T cell activation. With this cell model, NL4-3 virus clones with open and mutated nef reading frames were compared for replication competence. The clones with nef mutations showed reproducible and significant reductions in both rates of growth and maximal titers achieved. The degree of reduced replication was dependent on initial virus inoculum and the timing of T cell activation. The influence of nef was highly significant for induction of virus replication from a latent state within resting CD4 cells. Its effect was less apparent for virus infection of fully proliferating CD4 cells. This study demonstrates that nef confers a positive growth advantage to HIV-1 that becomes readily discernable in the primary cell setting of virus induction through T cell activation. The experimental cell model, which we describe here, provides not only a means to study nef function in vitro, but also provides important clues to the function of nef in HIV infection in vivo.

scholarly journals Early Divergence in Lymphoid Tissue Apoptosis between Pathogenic and Nonpathogenic Simian Immunodeficiency Virus Infections of Nonhuman Primates

2007 ◽  
Vol 82 (3) ◽  
pp. 1175-1184 ◽  
Author(s):  
M.-C. Cumont ◽  
O. Diop ◽  
B. Vaslin ◽  
C. Elbim ◽  
L. Viollet ◽  
...  
Keyword(s):  
T Cell ◽  
Lymph Nodes ◽  
Viral Replication ◽  
B Cell ◽  
T Cell Activation ◽  
Primary Infection ◽  
Cell Activation ◽  
Lymphocyte Apoptosis ◽  
Immunodeficiency Virus ◽  
Siv Infection

ABSTRACT The events that contribute to the progression to AIDS during the acute phase of a primate lentiviral infection are still poorly understood. In this study, we used pathogenic and nonpathogenic simian models of simian immunodeficiency virus (SIV) infection of rhesus macaques (RMs) and African green monkeys (AGMs), respectively, to investigate the relationship between apoptosis in lymph nodes and the extent of viral replication, immune activation, and disease outcome. Here, we show that, in SIVmac251-infected RMs, a marked increased in lymphocyte apoptosis is evident during primary infection at the level of lymph nodes. Interestingly, the levels of apoptosis correlated with the extent of viral replication and the rate of disease progression to AIDS, with higher apoptosis in RMs of Indian genetic background than in those of Chinese origin. In stark contrast, no changes in the levels of lymphocyte apoptosis were observed during primary infection in the nonpathogenic model of SIVagm-sab infection of AGMs, despite similarly high rates of viral replication. A further and early divergence between SIV-infected RMs and AGMs was observed in terms of the dynamics of T- and B-cell proliferation in lymph nodes, with RMs showing significantly higher levels of cycling cells (Ki67+) in the T-cell zones in association with relatively low levels of Ki67+ in the B-cell zones, whereas AGMs displayed a low frequency of Ki67+ in the T-cell area but a high proportion of Ki67+ cells in the B-cell area. As such, this study suggests that species-specific host factors determine an early immune response to SIV that predominantly involves either cellular or humoral immunity in RMs and AGMs, respectively. Taken together, these data are consistent with the hypotheses that (i) high levels of T-cell activation and lymphocyte apoptosis are key pathogenic factors during pathogenic SIV infection of RMs and (ii) low T-cell activation and apoptosis are determinants of the AIDS resistance of SIVagm-infected AGMs, despite high levels of SIVagm replication.

scholarly journals The Effect of Rosuvastatin on Markers of Immune Activation in Treatment-Naive Human Immunodeficiency Virus-Patients

2015 ◽  
Vol 3 (1) ◽  
Author(s):  
Robyn G. M. Weijma ◽  
Eric R. A. Vos ◽  
Jaap Ten Oever ◽  
Muriel Van Schilfgaarde ◽  
Lea M. Dijksman ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
T Cell Activation ◽  
Immune Activation ◽  
Cell Activation ◽  
Cd8 T Cell ◽  
Activation Markers ◽  
Cell Ratio ◽  
Immunodeficiency Virus ◽  
Treatment Naïve

Abstract Background.  Immune activation has been implicated in the excess mortality in human immunodeficiency virus (HIV)-infected patients, due to cardiovascular diseases and malignancies. Statins may modulate this immune activation. We assessed the capacity of rosuvastatin to mitigate immune activation in treatment-naive HIV-infected patients. Methods.  In a randomized double-blind placebo-controlled crossover study, we explored the effects of 8 weeks of rosuvastatin 20 mg in treatment-naive male HIV-infected patients (n = 28) on immune activation markers: neopterin, soluble Toll-like receptor (TLR)2, sTLR4, interleukin (IL)-6, IL-1Ra, IL-18, d-dimer, highly sensitive C-reactive protein, and CD38 and/or human leukocyte antigen-DR expression on T cells. Baseline data were compared with healthy male controls (n = 10). Furthermore, the effects of rosuvastatin on HIV-1 RNA, CD4/CD8 T-cell count, and low-density lipoprotein cholesterol were examined and side effects were registered. Results.  T-cell activation levels were higher in patients than in controls. Patients had higher levels of circulating IL-18, sTLR2, and neopterin (all P < .01). Twenty patients completed the study. Rosuvastatin increased the CD4/CD8 T-cell ratio (P = .02). No effect on other markers was found. Conclusions.  Patients infected with HIV had higher levels of circulating neopterin, IL-18, sTLR2, and T-cell activation markers. Rosuvastatin had a small but significant positive effect on CD4/CD8 T-cell ratio, but no influence on other markers of T-cell activation and innate immunity was identified (The Netherlands National Trial Register [NTR] NTR 2349, http://www.trialregister.nl/trialreg/index.asp).

scholarly journals Sex-Based Differences in Human Immunodeficiency Virus Type 1 Reservoir Activity and Residual Immune Activation

2018 ◽  
Vol 219 (7) ◽  
pp. 1084-1094 ◽  
Author(s):  
Eileen P Scully ◽  
Monica Gandhi ◽  
Rowena Johnston ◽  
Rebecca Hoh ◽  
Ainsley Lockhart ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
T Cell ◽  
Human Immunodeficiency Virus Type ◽  
Virus Type ◽  
T Cell Activation ◽  
Immune Activation ◽  
Cell Activation ◽  
Immunodeficiency Virus ◽  
Hiv 1

Abstract Plasma human immunodeficiency virus type 1 (HIV-1) RNA levels in women are lower early in untreated HIV-1 infection compared with those in men, but women have higher T-cell activation and faster disease progression when adjusted for viral load. It is not known whether these sex differences persist during effective antiretroviral therapy (ART), or whether they would be relevant for the evaluation and implementation of HIV-1 cure strategies. We prospectively enrolled a cohort of reproductive-aged women and matched men on suppressive ART and measured markers of HIV-1 persistence, residual virus activity, and immune activation. The frequency of CD4+ T cells harboring HIV-1 DNA was comparable between the sexes, but there was higher cell-associated HIV-1 RNA, higher plasma HIV-1 (single copy assay), and higher T-cell activation and PD-1 expression in men compared with women. These sex-related differences in immune phenotype and HIV-1 persistence on ART have significant implications for the design and measurement of curative interventions.

scholarly journals CD32+CD4+ T Cells Sharing B Cell Properties Increase With Simian Immunodeficiency Virus Replication in Lymphoid Tissues

2021 ◽  
Vol 12 ◽  
Author(s):  
Nicolas Huot ◽  
Philippe Rascle ◽  
Cyril Planchais ◽  
Vanessa Contreras ◽  
Caroline Passaes ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
B Cell ◽  
T Cell Activation ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Lymphoid Tissues ◽  
Cell Responses ◽  
Immunodeficiency Virus ◽  
Siv Infection

CD4 T cell responses constitute an important component of adaptive immunity and are critical regulators of anti-microbial protection. CD4+ T cells expressing CD32a have been identified as a target for HIV. CD32a is an Fcγ receptor known to be expressed on myeloid cells, granulocytes, B cells and NK cells. Little is known about the biology of CD32+CD4+ T cells. Our goal was to understand the dynamics of CD32+CD4+ T cells in tissues. We analyzed these cells in the blood, lymph nodes, spleen, ileum, jejunum and liver of two nonhuman primate models frequently used in biomedical research: African green monkeys (AGM) and macaques. We studied them in healthy animals and during viral (SIV) infection. We performed phenotypic and transcriptomic analysis at different stages of infection. In addition, we compared CD32+CD4+ T cells in tissues with well-controlled (spleen) and not efficiently controlled (jejunum) SIV replication in AGM. The CD32+CD4+ T cells more frequently expressed markers associated with T cell activation and HIV infection (CCR5, PD-1, CXCR5, CXCR3) and had higher levels of actively transcribed SIV RNA than CD32-CD4+T cells. Furthermore, CD32+CD4+ T cells from lymphoid tissues strongly expressed B-cell-related transcriptomic signatures, and displayed B cell markers at the cell surface, including immunoglobulins CD32+CD4+ T cells were rare in healthy animals and blood but increased strongly in tissues with ongoing viral replication. CD32+CD4+ T cell levels in tissues correlated with viremia. Our results suggest that the tissue environment induced by SIV replication drives the accumulation of these unusual cells with enhanced susceptibility to viral infection.

scholarly journals Probiotic supplementation reduces inflammatory profiles but does not prevent oral immune perturbations during SIV infection

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rhianna Jones ◽  
Kyle Kroll ◽  
Courtney Broedlow ◽  
Luca Schifanella ◽  
Scott Smith ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
T Cell Activation ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Rhesus Macaques ◽  
Oral Microbiome ◽  
Probiotic Supplementation ◽  
Siv Infection ◽  
Anti Inflammatory

AbstractHIV/SIV infections lead to massive loss of mucosal CD4 + T cells and breakdown of the epithelial mucosa resulting in severe microbial dysbiosis and chronic immune activation that ultimately drive disease progression. Moreover, disruption of one of the most understudied mucosal environments, the oral cavity, during HIV-induced immunosuppression results in significant microbial and neoplastic co-morbidities and contributes to and predicts distal disease complications. In this study we evaluated the effects of oral probiotic supplementation (PBX), which can stimulate and augment inflammatory or anti-inflammatory pathways, on early SIV infection of rhesus macaques. Our study revealed that similar to the GI mucosae, oral CD4 + T cells were rapidly depleted, and as one of the first comprehensive analyses of the oral microflora in SIV infection, we also observed significant modulation among two genera, Porphyromonas and Actinobacillus, early after infection. Interestingly, although PBX therapy did not substantially protect against oral dysbiosis or ameliorate cell loss, it did somewhat dampen inflammation and T cell activation. Collectively, these data provide one of the most comprehensive evaluations of SIV-induced changes in oral microbiome and CD4 + T cell populations, and also suggest that oral PBX may have some anti-inflammatory properties in lentivirus infections.

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