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Tsukalov, I.

Publications and source records attributed to Tsukalov, I..

6 recordsLinked to original sources

IFI16/AIM2 inflammasomes control Gal-9 and PVR in myeloid cells from PWH and their targeting improves immunotherapy against HIV-1

Chronic inflammation in people with HIV-1 (PWH) is associated with low CD4/CD8 T-cell ratios and inflammasome activation, which may impair monocyte (Mo) and monocyte-derived dendritic cell (MDDC) function and limit the efficacy of myeloid-based immunotherapies. Here, we investigated the role of inflammasome sensors in regulating immune ligands for TIM3 and TIGIT immune checkpoints in Mo and MDDC from PWH and their capacity to activate HIV-1-specific CD8+ T cells. Following TLR stimulation, galectin-9 (Gal-9), PVR and IL-1{beta} were preferentially upregulated in cells from PWH with low CD4/CD8 ratios. IFI16 and AIM2 expression was increased basally or inducible in Mo and co-localized with caspase-1 in these myeloid cells present in lymphoid tissues of HIV-1-infected humanized mice. Si-RNA or small molecule-mediated inhibition of IFI16/AIM2 reduced Gal-9 and PVR expression in MDDC and enhanced their ability to activate polyfunctional HIV-1-specific CD8+ T-cells displaying improved elimination of infected CD4+ T cells in vitro and in vivo. These findings identify IFI16 and AIM2 as key regulators of myeloid dysfunction and therapeutic targets to enhance HIV-1 immunotherapies.

immunology↗

Differential CD8+ T/NK cell-mediated reduction of HIV-1 replication after combination of ART with TIGIT or KLRG1 blockade in humanized mice

Expression of TIGIT and KLRG1 has been associated to an exhausted, dysfunctional state in natural killer (NK) and CD8+ T cells from people with HIV-1 (PWH), limiting the efficacy of immunotherapies aiming at achieving a functional cure of the infection. Antiretroviral therapy (ART) does not completely reverse this immune exhaustion, and its combination with blockade of immune checkpoint receptors such as TIGIT and KLRG1 could be a promising strategy to promote control of viral replication in PWH. However, the impact of targeting these two immune checkpoint receptors has not been evaluated in vivo. In this study, we used a humanized Bone Marrow, Liver and Thymus (hBLT) mouse model of HIV-1 infection to study the impact of ART in combination with aTIGIT or aKLRG1 or a bispecific aTIGIT/aKLRG1 mAbs. Our results indicated that combination of ART with either aTIGIT or aKLRG1 mAbs led to faster reduction of HIV-1 pVL. Furthermore, viral rebound after ART interruption (ATI) was delayed in mice treated with aTIGIT and aKLRG1 mAbs. Histological detection of HIV-1 p24 in the spleen was restricted to the white pulp in the aKLRG1 mAb-treated group, which correlated with higher infiltration of IFN{gamma}+ CD8+ T cells in these histological regions and with increased cytotoxic CD107a+ Granzyme B+ CD8+ T cells in the spleen. In contrast, control of HIV-1 replication induced by the aTIGIT mAb was associated with an increased splenic CD107a+ IFN{gamma}+ NKG2C+ CD57-adaptive NK cells. In contrast, combination of ART with a bispecific aTIGIT/aKLRG1 mAb was unable to efficiently suppress viral replication or delay viral rebound after ATI, potentially by inducing apoptosis of adaptive NKG2C+ NK. Together, these results suggest that combination of ART with individual TIGIT or KLRG1 blockade may be a promising immunotherapy strategy against HIV-1 by eliciting differential immune control mechanisms.

immunology↗

Induction of Resident Memory CD8+T cell Phenotypes to Eliminate the HIV reservoir

During analytical treatment interruption (ATI), failure to contain tissue HIV reservoirs remains a major barrier to remission. We conditioned peripheral blood mononuclear cells with cues that promote tissue-resident memory differentiation, aiming to reprogram HIV-specific CD8+T cells for these tissue microenvironments. Sequential IL-15/TGF-{beta}1-stimulation expanded proliferative CD103+CD39+ effector populations and restored polyfunctional HIV-specific CD8+T cell responses, irrespective of CD39 or PD-1 expression. Cytokine-stimulated CD8+T cells enhanced ex vivo elimination of the HIV reservoir, and within the induced effector pool, only CD69+ subsets expressing CD103+ or CD39+ eliminated intact HIV-1 genomes. Single-cell transcriptomics showed that IL-15/TGF-{beta}1 stimulation increased clonotypic diversity and expanded resident-like effector clusters with reduced immune-checkpoint receptor expression and augmented mitochondrial function, findings confirmed by flow cytometry. Engrafted recipients from a humanized mouse ATI model more effectively eliminated HIV+-reactivated cells after adoptive transfer of sequentially-treated CD8+T cells. Thus, IL-15/TGF-{beta}1-mediated CD8+T cell reprogramming represents a promising immunotherapy to enable immune control after ATI.

immunology↗

Combined Dendritic Cell And Anti-TIGIT Immunotherapy Potentiate Trail+ Memory NK Cells Against HIV-1 Infected Cells

Natural Killer (NK) cells are promising tools for the development of immunotherapies targeting persistently infected CD4+ T cells to potentially achieve remission in people with HIV-1 (PWH). However, the chronicity of HIV-1 infection limits the functional properties of NK cells, and additional approaches are needed to potentiate their cytotoxic activity against HIV-1-infected cells. In the present study, we analyzed the reinvigoration of functional NK cells from PWH after priming with autologous dendritic cells (DC) stimulated with nanoparticles containing Poly I:C (Nano-PIC). We show that improved natural cytotoxic function in NK cell from PWH associates with increased proportions of NKG2C+CD57- precursors of memory NK, which eliminate HIV-1 infected CD4+ T cells mainly through the TRAIL receptor. In addition, expression of TIGIT but not TIM3 limited increase in NKG2C+ memory NK cell precursors and associated with persistent dysfunctionality of NK cells after stimulation with Nano PIC-DC. Blockade of TIGIT restored functional capacities of NK cell from PWH eliminating HIV-1 infected cells in vitro. Moreover, combining of NK cell and Nano-PIC-DC with anti-TIGIT mAbs immunotherapy limited the expansion of HIV-1 infected cells in humanized immunodeficient NSG mice transplanted with CD4+ T cells from PWH in vivo. Such viral control was associated with preserved NKG2C memory NK cell precursors, increased expression of granzyme B and TRAIL on NK in tissue from transplanted NSG mice. Together, combination of Nano-PIC DC and anti-TIGIT antibodies may be a promising strategy to increase the efficacy of immunotherapies aimed at HIV-1 cure. One sentence summaryStimulation of memory NK with a combination of DC and anti-TIGIT antibodies increase their ability to eliminate HIV-1 infected CD4+ T cells in vitro and in vivo.

immunology↗

Antiviral State of CD1c+ cDC contributes to Increased Maturation and Activation of Cytotoxic Natural Killer cells in Sjogrens Syndrome

ObjectivePrimary Sjogrens syndrome (pSS) is an inflammatory autoimmune disorder characterized by damage of exocrine glands and linked to IFN responses and the induction of autoreactive adaptive immune cells. However, the role of innate immune cells in pSS pathology remains understudied. MethodsWe studied differential phenotypical characteristics of different NK cell, conventional dendritic cell (cDC) and monocyte subsets in the blood and salivary glands from pSS individuals. Transcriptional patterns of circulating cDC and Mo from pSS and healthy controls were also compared. Finally, in vivo alterations in these cell populations in the salivary gland were investigated in a mouse model. ResultsHere, we identified CD16+ CD56hi NK cells enriched in pSS patients which associates with higher natural cytotoxic function and increased proportions of circulating CD64+ CD1c+ cDC exhibiting antiviral transcriptional IFN signatures. CD64hi cDC and NK cell were detected infiltrated into the salivary glands from pSS patients and a murine SS model. CD1c+ cDC from patients with pSS expressed high levels of ligands for activating NK receptors and increased ability to activate NK cells ex vivo. Finally, the antiviral RIG-I and DDX60 sensors regulated the expression of NK cell receptor ligands on CD1c+ cDC. ConclusionsTherefore, the interplay of CD1c+ cDCs and NK cells could contribute to pSS pathology.

immunology↗

ART duration and immunometabolic state determine efficacy of DC-based treatment restoring functional HIV- specific CD8+ T cells in Chronic PLWH.

Dysfunction of CD8+ T cells in people living with HIV-1 (PLWH) receiving anti-retroviral therapy (ART) has restricted the efficacy of dendritic cell (DC)-based immunotherapies against HIV-1. Heterogeneous immune exhaustion and metabolic states of CD8+ T cells might differentially associate with dysfunction. However, specific parameters associated to functional restoration of CD8+ T cells after DC treatment have not been investigated in detail. Here, we studied the association of ART duration with memory subsets, exhaustion and metabolic profiles of CD8+ T cells from PLWH and improvement of polyfunctional and effector HIV-1 specific responses after stimulation with Gag-adjuvant-primed DC. HIV-1-specific CD8+ T cell responses from a larger proportion PLWH on ART for more than 10 years (LT-ARTp) improved polyfunctionality and capacity to eliminate autologous p24+ infected CD4+ T cells in vitro. In contrast, CD8+ T cells from PLWH on ART for less than a decade (ST-ARTp) were less responsive to DC treatment and functional improvement was limited in this group. This was associated with lower frequencies of central memory CD8+ T cells, increased co-expression of PD1 and TIGIT and reduced mitochondrial respiration and glycolytic induction upon TCR activation. In contrast, CD8+ T cells from LT-ARTp showed increased frequencies of TIM3+PD1-cells and preserved induction of glycolysis. Treatment of dysfunctional CD8+ T cells from ST-ARTp with combined anti-PD1 and anti-TIGIT antibodies plus a glycolysis promoting drug restored their ability to eliminate infected CD4+ T cells. Together, our study identifies specific immunometabolic parameters for different PLWH subgroups potentially useful for future personalized DC-based HIV-1 vaccines.

immunology↗