scholarly journals Neutrophils promote T-cell activation through the regulated release of CD44-bound Galectin-9 from the cell surface during HIV infection

PLoS Biology ◽  
2021 ◽  
Vol 19 (8) ◽  
pp. e3001387
Author(s):  
Garett Dunsmore ◽  
Eliana Perez Rosero ◽  
Shima Shahbaz ◽  
Deanna M. Santer ◽  
Juan Jovel ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Cell Surface ◽  
Hiv Infection ◽  
Cell Count ◽  
T Cell Activation ◽  
Cell Activation ◽  
Infected Individual ◽  
Cd4 T Cell ◽  
Cd4 T Cell Count

The interaction of neutrophils with T cells has been the subject of debate and controversies. Previous studies have suggested that neutrophils may suppress or activate T cells. Despite these studies, the interaction between neutrophils and T cells has remained a largely unexplored field. Here, based on our RNA sequencing (RNA-seq) analysis, we found that neutrophils have differential transcriptional and functional profiling depending on the CD4 T-cell count of the HIV-infected individual. In particular, we identified that neutrophils in healthy individuals express surface Galectin-9 (Gal-9), which is down-regulated upon activation, and is consistently down-regulated in HIV-infected individuals. However, down-regulation of Gal-9 was associated with CD4 T-cell count of patients. Unstimulated neutrophils express high levels of surface Gal-9 that is bound to CD44, and, upon stimulation, neutrophils depalmitoylate CD44 and induce its movement out of the lipid raft. This process causes the release of Gal-9 from the surface of neutrophils. In addition, we found that neutrophil-derived exogenous Gal-9 binds to cell surface CD44 on T cells, which promotes LCK activation and subsequently enhances T-cell activation. Furthermore, this process was regulated by glycolysis and can be inhibited by interleukin (IL)-10. Together, our data reveal a novel mechanism of Gal-9 shedding from the surface of neutrophils. This could explain elevated plasma Gal-9 levels in HIV-infected individuals as an underlying mechanism of the well-characterized chronic immune activation in HIV infection. This study provides a novel role for the Gal-9 shedding from neutrophils. We anticipate that our results will spark renewed investigation into the role of neutrophils in T-cell activation in other acute and chronic conditions, as well as improved strategies for modulating Gal-9 shedding.

scholarly journals Relationship between T Cell Activation and CD4+T Cell Count in HIV‐Seropositive Individuals with Undetectable Plasma HIV RNA Levels in the Absence of Therapy

2008 ◽  
Vol 197 (1) ◽  
pp. 126-133 ◽  
Author(s):  
Peter W. Hunt ◽  
Jason Brenchley ◽  
Elizabeth Sinclair ◽  
Joseph M. McCune ◽  
Michelle Roland ◽  
...  
Keyword(s):  
T Cell ◽  
Cell Count ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cd4 T Cell ◽  
Hiv Rna ◽  
Undetectable Plasma ◽  
Hiv Seropositive ◽  
Cd4 T Cell Count ◽  
Rna Levels

scholarly journals A Subset of Extreme Human Immunodeficiency Virus (HIV) Controllers Is Characterized by a Small HIV Blood Reservoir and a Weak T-Cell Activation Level

2017 ◽  
Vol 4 (2) ◽  
Author(s):  
Etienne Canouï ◽  
Camille Lécuroux ◽  
Véronique Avettand-Fenoël ◽  
Marine Gousset ◽  
Christine Rouzioux ◽  
...  
Keyword(s):  
Human Immunodeficiency Virus ◽  
Viral Load ◽  
T Cell ◽  
Cell Count ◽  
T Cell Activation ◽  
Cell Activation ◽  
Cd4 T Cell ◽  
Hiv Dna ◽  
Immunodeficiency Virus ◽  
Cd4 T Cell Count

Abstract Background Human immunodeficiency virus controllers (HICs) form a heterogeneous group of patients with regard to formal definitions, immunologic characteristics, and changes over time in viral load. Patients and Methods The HICs with undetectable viral load ([uHICs] ie, for whom a viral load had never been detected with routine assays; n = 52) were compared with 178 HICs with blips during the follow up (bHICs). Clinical characteristics, ultrasensitive HIV-ribonucleic acid (RNA) and HIV-deoxyribonucleic acid (DNA) loads, HIV1-Western blot profiles, and immune parameters were analyzed. Results Relative to bHICs, uHICs had significantly lower ultrasensitive plasma HIV-RNA loads (P < .0001) and HIV-DNA levels in peripheral blood mononuclear cells (P = .0004), higher CD4+ T-cell count (P = .04) at enrollment, and lower T-cell activation levels. Between diagnosis and inclusion in the cohort, the CD4+ T-cell count had not changed in uHICs but had significantly decreased in bHICs. Twenty-one percent of the uHICs lacked specific anti-HIV immunoglobulin G antibodies, and these individuals also had very low levels of HIV-DNA. Half of the uHICs had a protective human leukocyte antigen (HLA) allele (-B57/58/B27), a weak CD8+ T-cell response, and very small HIV-DNA reservoir. Conclusions We suggest that an interesting HIC phenotype combines protective HLA alleles, low level of HIV blood reservoirs, and reduced immune activation. Prospective studies aimed at evaluating the benefit of combined antiretroviral therapy in HICs might take into account the identification of uHICs and bHICs.

The Effect of Antiretroviral Therapy on IL-6, IL-1β, TNF-α, IFN-γ Levels and their Relationship with HIV-RNA and CD4+ T Cells in HIV Patients

2020 ◽  
Vol 18 (5) ◽  
pp. 354-361
Author(s):  
Gülay Okay ◽  
Meliha Meric Koc ◽  
Eray Metin Guler ◽  
Ayşegül Yabaci ◽  
Abdürrahim Kocyigit ◽  
...  
Keyword(s):  
T Cell ◽  
Hiv Infection ◽  
Cell Count ◽  
Cd4 T Cell ◽  
Positive Correlation ◽  
Hiv Rna ◽  
Tnf Α ◽  
Cytokine Levels ◽  
Ifn Γ ◽  
Cd4 T Cell Count

Background: Serum cytokine levels over the course of HIV infection usually increase with immunosuppression and decrease after antiretroviral treatment (ART). Objectives: The aim of the study is to compare cytokine levels between HIV-infected patients (HIP) and controls and investigate the relationship between CD4+T cell count, HIV-RNA levels, and cytokine levels. Methods: The study subjects comprised ART-naive HIP (n=30) with no comorbidities and age-and sex-matched healthy controls. We measured levels of IL-6, IL-1β, TNF-α, and IFN-γ in serum samples of HIP at the beginning and at month 6 of ART and in controls. Results: The mean age of the study subjects was 38.7 ±10.3 years, with men making up 86.7% of the study subjects (n=26). IL-6, IL-1β, and TNF-α levels were significantly higher in both ART-naive (p<0.001, p=0.002, p=0.001) and ART-experienced HIP (p<0.001) than controls. The IFN-γ level was lower in both ART-naive and ART-experienced HIP compared to controls (p=0.082 and p=0.002). There was a positive correlation between the CD4+T cell count and serum concentration of IFN- γ(r=0.320, p<0.05). While the serum IFN-γ concentration showed a negative correlation with the HIVRNA level(r=-0.412, p<0.001), the serum IL-1β, IL-6, and TNF-α concentrations showed a positive correlation with the HIV-RNA level (r=0.349, p<0.001; r:0.54, p<0.001; r:0.438, p<0.00). Conclusions: Although serum concentrations of IL-6, IL-1β and TNF-α showed a significant decrease after ART, they were still significantly higher than the controls. IFN-γ responded differently to ART compared to the other cytokines, indicating that it may play a distinct and important role in the pathogenesis of HIV infection.

scholarly journals HIV-Related Arterial Stiffness in Malawian Adults Is Associated With the Proportion of PD-1–Expressing CD8+ T Cells and Reverses With Antiretroviral Therapy

2019 ◽  
Vol 219 (12) ◽  
pp. 1948-1958 ◽  
Author(s):  
Christine Kelly ◽  
Henry C Mwandumba ◽  
Robert S Heyderman ◽  
Kondwani Jambo ◽  
Raphael Kamng’ona ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
Arterial Stiffness ◽  
Cell Count ◽  
Cd8 T Cells ◽  
Sub Saharan Africa ◽  
Cd4 T Cell ◽  
Sub Saharan ◽  
Cd4 T Cell Count

Abstract Background The contribution of immune activation to arterial stiffness and its reversibility in human immunodeficiency virus (HIV)–infected adults in sub-Saharan Africa is unknown. Methods HIV-uninfected and HIV-infected Malawian adults initiating antiretroviral therapy (ART) with a CD4+ T-cell count of &lt;100 cells/μL were enrolled and followed for 44 weeks; enrollment of infected adults occurred 2 weeks after ART initiation. We evaluated the relationship between carotid femoral pulse wave velocity (cfPWV) and T-cell activation (defined as HLA-DR+CD38+ T cells), exhaustion (define as PD-1+ T cells), and senescence (defined as CD57+ T cells) and monocyte subsets, using normal regression. Results In 279 HIV-infected and 110 HIV-uninfected adults, 142 (37%) had hypertension. HIV was independently associated with a 12% higher cfPWV (P = .02) at baseline and a 14% higher cfPWV at week 10 (P = .02), but the increases resolved by week 22. CD4+ and CD8+ T-cell exhaustion were independently associated with a higher cfPWV at baseline (P = .02). At 44 weeks, arterial stiffness improved more in those with greater decreases in the percentage of CD8+ T cells and the percentage of PD-1+CD8+ T cells (P = .01 and P = .03, respectively). When considering HIV-infected participants alone, the adjusted arterial stiffness at week 44 tended to be lower in those with higher baseline percentage of PD-1+CD8+ T cells (P = .054). Conclusions PD-1+CD8+ T-cells are associated with HIV-related arterial stiffness, which remains elevated during the first 3 months of ART. Resources to prevent cardiovascular disease in sub-Saharan Africa should focus on blood pressure reduction and individuals with a low CD4+ T-cell count during early ART.

CD4+ T cell count, HIV-1 viral loads and demographic variables of newly identified patients with HIV infection in Wuhan, China

2013 ◽  
Vol 85 (10) ◽  
pp. 1687-1691 ◽  
Author(s):  
Man-Qing Liu ◽  
Li Tang ◽  
Wen-Hua Kong ◽  
Ze-Rong Zhu ◽  
Jin-Song Peng ◽  
...  
Keyword(s):  
T Cell ◽  
Hiv Infection ◽  
Cell Count ◽  
Demographic Variables ◽  
Cd4 T Cell ◽  
Viral Loads ◽  
Hiv 1 ◽  
Cd4 T Cell Count

scholarly journals Isolevuglandin-Modified Cardiac Proteins Drive CD4+ T Cell Activation in the Heart and Promote Cardiac Dysfunction

Circulation ◽  
2021 ◽  
Author(s):  
Njabulo Ngwenyama ◽  
Annet Kirabo ◽  
Mark Aronovitz ◽  
Francisco Velázquez ◽  
Francisco Carrillo-Salinas ◽  
...  
Keyword(s):  
T Cells ◽  
T Cell ◽  
Antigen Presentation ◽  
T Cell Activation ◽  
Cardiac Dysfunction ◽  
Cd4 T Cells ◽  
Cell Activation ◽  
Cd4 T Cell ◽  
Myocardial Oxidative Stress

Background: Despite the well-established association between T cell-mediated inflammation and non-ischemic heart failure (HF), the specific mechanisms triggering T cell activation during the progression of HF and the antigens involved are poorly understood. We hypothesized that myocardial oxidative stress induces the formation of isolevuglandin (IsoLG)-modified proteins that function as cardiac neoantigens to elicit CD4+ T cell receptor (TCR) activation and promote HF. Methods: We used transverse aortic constriction (TAC) in mice to trigger myocardial oxidative stress and T cell infiltration. We profiled the TCR repertoire by mRNA sequencing of intramyocardial activated CD4+ T cells in Nur77 GFP reporter mice, which transiently express GFP upon TCR engagement. We assessed the role of antigen presentation and TCR specificity in the development of cardiac dysfunction using antigen presentation-deficient MhcII -/- mice, and TCR transgenic OTII mice that lack specificity for endogenous antigens. We detected IsoLG-protein adducts in failing human hearts. We also evaluated the role of reactive oxygen species (ROS) and IsoLGs in eliciting T cell immune responses in vivo by treating mice with the antioxidant TEMPOL, and the IsoLG scavenger 2-hydroxybenzylamine (2-HOBA) during TAC, and ex-vivo in mechanistic studies of CD4+ T cell proliferation in response to IsoLG-modified cardiac proteins. Results: We discovered that TCR antigen recognition increases in the left ventricle (LV) as cardiac dysfunction progresses, and identified a limited repertoire of activated CD4+ T cell clonotypes in the LV. Antigen presentation of endogenous antigens was required to develop cardiac dysfunction since MhcII -/- mice reconstituted with CD4+ T cells, and OTII mice immunized with their cognate antigen were protected from TAC-induced cardiac dysfunction despite the presence of LV-infiltrated CD4+ T cells. Scavenging IsoLGs with 2-HOBA reduced TCR activation and prevented cardiac dysfunction. Mechanistically, cardiac pressure overload resulted in ROS dependent dendritic cell accumulation of IsoLG-protein adducts which induced robust CD4+ T cell proliferation. Conclusions: Collectively, our study demonstrates an important role of ROS-induced formation of IsoLG-modified cardiac neoantigens that lead to TCR-dependent CD4+ T cell activation within the heart.

scholarly journals PIMATM point-of-care testing for CD4 counts in predicting antiretroviral initiation in HIV-infected individuals in KwaZulu-Natal, Durban, South Africa

2016 ◽  
Vol 17 (1) ◽  
Author(s):  
Mandisa Skhosana ◽  
Shabashini Reddy ◽  
Tarylee Reddy ◽  
Siphelele Ntoyanto ◽  
Elizabeth Spooner ◽  
...  
Keyword(s):  
South Africa ◽  
T Cells ◽  
T Cell ◽  
Antiretroviral Therapy ◽  
Cell Count ◽  
Point Of Care ◽  
Cd4 T Cell ◽  
Cell Counts ◽  
Kwazulu Natal ◽  
Cd4 T Cell Count

Introduction: Limited information is available on the usefulness of the PIMATM analyser in predicting antiretroviral treatment eligibility and outcome in a primary healthcare clinic setting in disadvantaged communities in KwaZulu-Natal, South Africa.Materials and methods: The study was conducted under the eThekwini Health Unit, Durban, KwaZulu-Natal. Comparison of the enumeration of CD4+ T-cells in 268 patients using the PIMATM analyser and the predicate National Health Laboratory Services (NHLS) was undertaken during January to July 2013. Bland-Altman analysis to calculate bias and limits of agreement, precision and levels of clinical misclassification at various CD4+ T-cell count thresholds was performed.Results: There was high precision of the PIMATM control bead cartridges with low and normal CD4+ T-cell counts using three different PIMATM analysers (%CV < 5). Under World Health Organization (WHO) guidelines (≤ 500 cells/mm3), the sensitivity of the PIMATM analyser was 94%, specificity 78% and positive predictive value (PPV) 95%. There were 24 (9%) misclassifications, of which 13 were false-negative in whom the mean bias was 149 CD4+ T-cells/mm3. Most (87%) patients returned for their CD4 test result but only 67% (110/164) of those eligible (≤ 350 cells/mm3) were initiated on antiretroviral therapy (ART) with a time to treatment of 49 days (interquartile range [IQR], 42–64 days).Conclusion: There was adequate agreement between PIMATM analyser and predicate NHLS CD4+ T-cell count enumeration (≤ 500 cells/mm3) in adult HIV-positive individuals. The high PPV, sensitivity and acceptable specificity of the PIMATM analyser technology lend it as a reliable tool in predicting eligibility and rapid linkage to care in ART programmes.Keywords: HIV; Point of Care; PIMATM CD4+ T cell counts; antiretroviral therapy; prediction/eligibility; South Africa

Sign in / Sign up

Export Citation Format

Share Document