Epigenetic Mechanisms Underlying HIV-Infection Induced Susceptibility of CD4+ T Cells to Enhanced Activation-Induced FasL Expression and Cell Death.
J Acquir Immune Defic Syndr
; 86(1): 128-137, 2021 01 01.
Article
en En
| MEDLINE
| ID: mdl-33093334
ABSTRACT
BACKGROUND:
Chronic immune activation and CD4 T cell depletion are significant pathogenic features of HIV infection. Expression of Fas ligand (FasL), a key mediator of activation-induced cell death in T cells, is elevated in people living with HIV-1 infection (PLWH). However, the epigenetic mechanisms underlying the enhanced induction of FasL expression in CD4 T lymphocytes in PLWH are not completely elucidated. Hence, the current work examined the effect of HIV infection on FasL promoter-associated histone modifications and transcriptional regulation in CD4 T lymphocytes in PLWH.METHOD:
Flow cytometric analysis was performed to examine the Fas-FasL expression on total CD4 T cells and naïve/memory CD4 T cell subsets. Epigenetic FasL promoter histone modifications were investigated by chromatin immunoprecipitation-quantitative real-time polymerase chain reaction analysis using freshly isolated total CD4 T lymphocytes from HIV-1 infected and noninfected individuals.RESULTS:
All naïve/memory CD4 T cell subsets from PLWH showed markedly greater frequency of FasL expression. Notably, examination of functional outcome of FasL/Fas co-expression demonstrated the preferential susceptibility of Tcm and Tem subsets to activation-induced apoptosis. Importantly, these CD4 T cells collectively demonstrated a distinct FasL promoter histone profile involving a coordinated cross-talk between histone H3 modifications leading to enhanced FasL gene expression. Specifically, levels of transcriptionally permissive histone H3K4-trimethylation (H3K4Me3) and histone H3K9-acetylation (H3K9Ac) were increased, with a concomitant decrease in the repressive H3K9-trimethylation (H3K9Me3).CONCLUSION:
The present work demonstrates that epigenetic mechanisms involving promoter-histone modifications regulate transcriptional competence and FasL expression in CD4 T cells from PLWH and render them susceptible to activation-induced cell death.
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Linfocitos T CD4-Positivos
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Infecciones por VIH
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Muerte Celular
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Epigénesis Genética
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Proteína Ligando Fas
Límite:
Adult
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Female
/
Humans
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Male
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Middle aged
Idioma:
En
Revista:
J Acquir Immune Defic Syndr
Asunto de la revista:
SINDROME DA IMUNODEFICIENCIA ADQUIRIDA (AIDS)
Año:
2021
Tipo del documento:
Article