1. |
- Buggert, Marcus, et al.
(författare)
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CD4+ T cells with an activated and exhausted phenotype distinguish immunodeficiency during aviremic HIV-2 infection
- 2016
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Ingår i: AIDS. - 0269-9370. ; 30:16, s. 2415-2426
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:: HIV-2 represents an attenuated form of HIV, where many infected individuals remain “aviremic” without antiretroviral therapy (ART). However, aviremic HIV-2 disease progression exits, and in the current study we therefore aimed to examine if specific pathological characteristics of CD4+ T cells are linked to such outcome. DESIGN:: HIV-seronegative (n=25), HIV-1 (n?=?33), HIV-2 (n?=?39, of whom 26 were aviremic), and HIV-1/2 dually (HIV-D) (n?=?13) infected subjects were enrolled from an occupational cohort in Guinea-Bissau. METHODS:: CD4+ T cell differentiation, activation, exhaustion, senescence, and transcription factors were assessed by polychromatic flow cytometry. Multidimensional clustering bioinformatic tools were used to identify CD4+ T cell subpopulations linked to infection type and disease stage. RESULTS:: HIV-2-infected individuals had early- and late-differentiated CD4+ T cell clusters with lower activation (CD38+HLA-DR+) and exhaustion (PD-1) than HIV-1 and HIV-D-infected subjects. We also noted that aviremic HIV-2-infected individuals possessed fewer CD4+ T cells with pathological signs compared to other HIV-infected groups. Still, compared to HIV-seronegatives, aviremic HIV-2-infected subjects had T-bet+ CD4+ T cells that showed elevated immune activation/exhaustion, and particularly the frequencies of PD-1+ cells were associated with suboptimal percentage of CD4+ T cells. CONCLUSIONS:: Increased frequencies of CD4+ T cells with an activated/exhausted phenotype correlate with exacerbated immunodeficiency in aviremic HIV-2-infected individuals. Thus, these findings encourage studies on the introduction of ART also to individuals with aviremic HIV-2 infection.
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2. |
- Bächle, Susanna M., et al.
(författare)
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Elevated levels of iNKT cell and NK cell activation correlate with disease progression in HIV-1 and HIV-2 infections
- 2016
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Ingår i: AIDS. - 0269-9370. ; 30:11, s. 1713-1722
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:: In this study we aimed to investigate the frequency and activation of invariant natural killer T (iNKT) cells and natural killer (NK) cells among HIV-1, HIV-2, or dually HIV-1/HIV-2 (HIV-D)-infected individuals, in relation to markers of disease progression. DESIGN:: Whole blood samples were collected from treatment-naïve HIV-1 (n?=?23), HIV-2 (n?=?34) and HIV-D (n?=?11) infected individuals, as well as HIV-seronegative controls (n?=?25), belonging to an occupational cohort in Guinea-Bissau. METHODS:: Frequencies and activation levels of iNKT and NK cell subsets were analysed using multi-colour flow cytometry and results were related to HIV-status, CD4+ T cell levels, viral load, and T cell activation. RESULTS:: HIV-1, HIV-D, and viremic HIV-2 individuals had lower numbers of CD4+ iNKT cells in circulation compared to seronegative controls. Numbers of CD56 NK cells were also reduced in HIV-infected individuals as compared to control subjects. Notably, iNKT cell and NK cell activation levels, assessed by CD38 expression, were increased in HIV-1 and HIV-2 single, as well as dual, infections. HIV-2 viremia was associated with elevated activation levels in CD4+ iNKT cells, CD56 and CD56 NK cells, as compared to aviremic HIV-2 infection. Additionally, disease markers such as CD4+ T cell percentages, viral load, and CD4+ T cell activation were associated with CD38 expression levels of both iNKT and NK cells, which activation levels also correlated with each other. CONCLUSIONS:: Our data indicate that elevated levels of iNKT cell and NK cell activation are associated with viremia and disease progression markers in both HIV-1 and HIV-2 infections.
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3. |
- Johansson, Emil, et al.
(författare)
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Hierarchical Clustering and Trajectory Analyses Reveal Viremia-Independent B-Cell Perturbations in HIV-2 Infection
- 2022
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Ingår i: Cells. - : MDPI. - 2073-4409. ; 11:19
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Tidskriftsartikel (refereegranskat)abstract
- Time to AIDS in HIV-2 infection is approximately twice as long compared to in HIV-1 infection. Despite reduced viremia, HIV-2-infected individuals display signs of chronic immune activation. In HIV-1-infected individuals, B-cell hyperactivation is driven by continuous antigen exposure. However, the contribution of viremia to B-cell perturbations in HIV-2-infected individuals remains largely unexplored. Here, we used polychromatic flow cytometry, consensus hierarchical clustering and pseudotime trajectory inference to characterize B-cells in HIV-1- or HIV-2-infected and in HIV seronegative individuals. We observed increased frequencies of clusters containing hyperactivated T-bethighCD95highCD27int and proliferating T-bet+CD95highCD27+CD71+ memory B-cells in viremic HIV-1 (p < 0.001 and p < 0.001, respectively), viremic HIV-2 (p < 0.001 and p = 0.014, respectively) and in treatment-naïve aviremic HIV-2 (p = 0.004 and p = 0.020, respectively)-infected individuals, compared to seronegative individuals. In contrast, these expansions were not observed in successfully treated HIV-1-infected individuals. Finally, pseudotime trajectory inference showed that T-bet-expressing hyperactivated and proliferating memory B-cell populations were located at the terminal end of two trajectories, in both HIV-1 and HIV-2 infections. As the treatment-naïve aviremic HIV-2-infected individuals, but not the successfully ART-treated HIV-1-infected individuals, showed B-cell perturbations, our data suggest that aviremic HIV-2-infected individuals would also benefit from antiretroviral treatment.
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4. |
- Scharf, Lydia, et al.
(författare)
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Inverted CD8 T-Cell Exhaustion and Co-Stimulation Marker Balance Differentiate Aviremic HIV-2-Infected From Seronegative Individuals
- 2021
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Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 12
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Tidskriftsartikel (refereegranskat)abstract
- HIV-2 is less pathogenic compared to HIV-1. Still, disease progression may develop in aviremic HIV-2 infection, but the driving forces and mechanisms behind such development are unclear. Here, we aimed to reveal the immunophenotypic pattern associated with CD8 T-cell pathology in HIV-2 infection, in relation to viremia and markers of disease progression. The relationships between pathological differences of the CD8 T-cell memory population and viremia were analyzed in blood samples obtained from an occupational cohort in Guinea-Bissau, including HIV-2 viremic and aviremic individuals. For comparison, samples from HIV-1- or dually HIV-1/2-infected and seronegative individuals were obtained from the same cohort. CD8 T-cell exhaustion was evaluated by the combined expression patterns of activation, stimulatory and inhibitory immune checkpoint markers analyzed using multicolor flow cytometry and advanced bioinformatics. Unsupervised multidimensional clustering analysis identified a cluster of late differentiated CD8 T-cells expressing activation (CD38+, HLA-DRint/high), co-stimulatory (CD226+/-), and immune inhibitory (2B4+, PD-1high, TIGIThigh) markers that distinguished aviremic from viremic HIV-2, and treated from untreated HIV-1-infected individuals. This CD8 T-cell population displayed close correlations to CD4%, viremia, and plasma levels of IP-10, sCD14 and beta-2 microglobulin in HIV-2 infection. Detailed analysis revealed that aviremic HIV-2-infected individuals had higher frequencies of exhausted TIGIT+ CD8 T-cell populations lacking CD226, while reduced percentage of stimulation-receptive TIGIT-CD226+ CD8 T-cells, compared to seronegative individuals. Our results suggest that HIV-2 infection, independent of viremia, skews CD8 T-cells towards exhaustion and reduced co-stimulation readiness. Further knowledge on CD8 T-cell phenotypes might provide help in therapy monitoring and identification of immunotherapy targets.
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