scholarly journals High-dimensional mass cytometry analysis of NK cell alterations in AML identifies a subgroup with adverse clinical outcome

2021 ◽  
Vol 118 (22) ◽  
pp. e2020459118
Author(s):  
Anne-Sophie Chretien ◽  
Raynier Devillier ◽  
Samuel Granjeaud ◽  
Charlotte Cordier ◽  
Clemence Demerle ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Nk Cells ◽  
Cell Function ◽  
Immune Escape ◽  
Nk Cell ◽  
Negative Impact ◽  
Statistical Significance ◽  
High Dimensional ◽  
Adverse Clinical Outcome ◽  
Mass Cytometry

Natural killer (NK) cells are major antileukemic immune effectors. Leukemic blasts have a negative impact on NK cell function and promote the emergence of phenotypically and functionally impaired NK cells. In the current work, we highlight an accumulation of CD56−CD16+ unconventional NK cells in acute myeloid leukemia (AML), an aberrant subset initially described as being elevated in patients chronically infected with HIV-1. Deep phenotyping of NK cells was performed using peripheral blood from patients with newly diagnosed AML (n = 48, HEMATOBIO cohort, NCT02320656) and healthy subjects (n = 18) by mass cytometry. We showed evidence of a moderate to drastic accumulation of CD56−CD16+ unconventional NK cells in 27% of patients. These NK cells displayed decreased expression of NKG2A as well as the triggering receptors NKp30 and NKp46, in line with previous observations in HIV-infected patients. High-dimensional characterization of these NK cells highlighted a decreased expression of three additional major triggering receptors required for NK cell activation, NKG2D, DNAM-1, and CD96. A high proportion of CD56−CD16+ NK cells at diagnosis was associated with an adverse clinical outcome and decreased overall survival (HR = 0.13; P = 0.0002) and event-free survival (HR = 0.33; P = 0.018) and retained statistical significance in multivariate analysis. Pseudotime analysis of the NK cell compartment highlighted a disruption of the maturation process, with a bifurcation from conventional NK cells toward CD56−CD16+ NK cells. Overall, our data suggest that the accumulation of CD56−CD16+ NK cells may be the consequence of immune escape from innate immunity during AML progression.

scholarly journals High-dimensional mass cytometry analysis of NK cell alterations in Acute Myeloid Leukemia identifies a subgroup with adverse clinical outcome

2020 ◽  
Author(s):  
Anne-Sophie Chretien ◽  
Raynier Devillier ◽  
Samuel Granjeaud ◽  
Charlotte Cordier ◽  
Clemence Demerle ◽  
...  
Keyword(s):  
Clinical Outcome ◽  
Nk Cells ◽  
Myeloid Leukemia ◽  
Immune Escape ◽  
Nk Cell ◽  
High Dimensional ◽  
Maturation Process ◽  
Adverse Clinical Outcome ◽  
Mass Cytometry ◽  
Acute Myeloid

ABSTRACTNatural killer (NK) cells are major anti-leukemic immune effectors. Leukemic blasts have a negative impact on NK cell function and promote the emergence of phenotypically and functionally impaired NK cells. In the present work, we highlight an accumulation of CD56-CD16+ unconventional NK cells in acute myeloid leukemia (AML), an aberrant subset initially described as being elevated in patients chronically infected with HIV-1. Deep phenotyping of NK cells was performed using peripheral blood from patients with newly-diagnosed AML (N=48, HEMATOBIO cohort, NCT02320656) and healthy subjects (N=18) by mass cytometry. We evidenced a moderate to drastic accumulation of CD56- CD16+ unconventional NK cells in 27% of patients. These NK cells displayed decreased expression of NKG2A as well as the triggering receptors NKp30, and NKp46, in line with previous observations in HIV-infected patients. High-dimensional characterization of these NK cells highlighted a decreased expression of three additional major triggering receptors required for NK cell activation, NKG2D, DNAM-1, and CD96. A high proportion of CD56-CD16+ NK cells at diagnosis was associated with an adverse clinical outcome, with decreased overall survival (HR=0.13; P=.0002) and event-free survival (HR=0.33; P=.018), and retained statistical significance in multivariate analysis. Pseudo-time analysis of the NK cell compartment highlighted a disruption of the maturation process, with a bifurcation from conventional NK cells toward CD56-CD16+ NK cells. Overall, our data suggest that the accumulation of CD56-CD16+ NK cells may be the consequence of immune escape from innate immunity during AML progression.SignificanceThis work provides the first report of accumulation of unconventional CD56-CD16+ NK cells in non-virally induced malignancies. Pseudotime analysis highlights a bifurcation point occurring during the course of NK cell maturation, providing elements regarding the possible origin of CD56-CD16+ NK cells. Increased frequency of CD56-CD16+ NK cells is associated with adverse clinical outcome in AML and might contribute, as well as other maturation defects, to a defective control of AML progression. Overall, accumulation of CD56-CD16+ NK cells could be an important feature of immune escape from innate immunity.Graphical abstractKey pointsA disruption in the maturation process of NK cells leads to accumulation of unconventional CD56- CD16+ NK cells in patients with AMLHigh frequency of CD56-CD16+ NK cells is associated with adverse clinical outcome

Myeloma-Derived Exosomes and Soluble Factors Suppress Natural Killer Cell Function

Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 2066-2066
Author(s):  
Tarun K. Garg ◽  
Jessica I Gann ◽  
Priyangi A Malaviarachchi ◽  
Kate Stone ◽  
Veronica Macleod ◽  
...  
Keyword(s):  
Flow Cytometry ◽  
Nk Cells ◽  
Natural Killer ◽  
Adhesion Molecules ◽  
Research Funding ◽  
Cell Function ◽  
Immune Escape ◽  
Nk Cell ◽  
Soluble Factors

Abstract Introduction The complex makeup of the tumor microenvironment (ME) exerts selective pressure on cancer cells leading to immune escape, and novel immunotherapeutic interventions have emerged from evolving knowledge of the immune system and tumor cells. Natural killer (NK) cells are innate immune cells that exert potent anti-tumor effects. Previously we have reported that ex vivo expansion of NK cells by co-culture PBMCs with K562mbIL15-41BBL can generate large numbers of highly active expanded NK cells (ENKs). These ENKs expand further upon adoptive transfer in vivo both in a murine model and in patients (Garg et al. 2012, Szmania et al. 2015), and have been shown to persist and retain their cytolytic ability. We are currently applying ENK therapy in a Phase II clinical trial at our institute in gene expression profiling-defined high-risk multiple myeloma (MM), a patient population which fares poorly despite the use of novel drugs and autologous stem cell transplantation. A potential obstacle to successful NK cell-based therapies is the suppression of NK cells in the MM bone marrow ME (BM-ME) by immunosuppressive cells, various soluble factors (SF), microRNAs, and exosomes. Exosomes are endosomal-derived, 30-130nm microvesicles present in almost all body fluids. Their number is significantly higher in cancer patients. Tumor-derived exosomes contain a wide range of bioactive molecules, such as microRNA, RNA, DNA and protein, and play a major role in immune escape, promoting tumor progression. Their size, structure, and presence in serum allow them to transport their cargo to distant targets. This study was designed to characterize the potential adverse effects of myeloma-derived exosomes (MEXs) and myeloma-derived SF (MSF) on NK cell function and determine if such inhibition can be overcome by cytokine support. Methods MEXs were isolated from OPM2 myeloma cell line-derived conditioned media (MCM) using the Total Isolation Reagent (Life Technologies, Carlsbad CA). Transmission electron microscopy (TEM), flow cytometry, and western blot (WB) analysis were used for characterization of exosomes. Fresh NK cells (non-activated) and ENKs were incubated with MCM or MEXs and evaluated for their viability and cytolytic ability in standard 4-hour chromium release assays. Flow cytometry was used to evaluate the immunophenotype of these cells, including activation, costimulatory, inhibitory receptors, and adhesion molecules. Results TEM confirmed the presence of exosomes in MCM (size and morphology). Interestingly, OPM2-derived MEXs did not express the exosome-specific marker CD9, but did express CD63, and CD81. Flow cytometry showed that MEXs contain MICA/B, TGFβ, TRAIL-R1, TRAIL-R2, MHC class I, HLA-E, and ICAM3. NK cells exposed to MEXs demonstrated a dose-dependent, significant decrease in specific lysis of the MM cell lines JJN3, OPM2, and U266 in cytotoxicity assays compared to control NK cells (13%-51%, p<0.0005). In addition, a time-dependent decrease in NK cell-mediated lysis was observed in these MM cell lines at 24hours (14%-34%) versus 48hours (30%-48%; p<0.0005). A similar downward trend in the activity of ENKs incubated with MEXs was also noted but to a lesser extent. We hypothesize that highly-activated ENKs are able to partially overcome MEX-mediated inhibition compare to resting NK cells. We also noted a considerable decrease in the cytolytic ability of ENKs incubated with MCM which contains suppressive soluble factors in addition to MEXs (28%-58%, p<0.0005). Further, this suppression in ENK activity was partly rescued by fresh IL2 incubation (18-36%, p<0.01). Many of the activating receptors (NKp46, NKp30, NKp44, NKG2D), costimulatory receptors (2B4, NTB-A, NKp80, DNAM-1), activation markers (CD26, CD69), and adhesion molecules (LFA-1, CD54) were down regulated on the ENK cells incubated with MCM. However, differences were not as significant in these receptors on ENK cells incubated with MEX. Conclusion MEXs and other SF released from myeloma cells are capable of modulating the function and phenotype of NK cells and ENKs. MCM is more immunosuppressive as it contains both MEX and MSF. Cytolytic ability of ENKs could be partially restored by incubation in fresh IL2 medium. Further characterization of MEXs and MCM by proteomics is in progress. (Data will be presented). Disclosures Davies: Takeda: Consultancy, Honoraria; Janssen: Consultancy, Honoraria; Celgene: Consultancy, Honoraria. Morgan:Bristol Meyers: Consultancy, Honoraria; Janssen: Research Funding; Univ of AR for Medical Sciences: Employment; Takeda: Consultancy, Honoraria; Celgene: Consultancy, Honoraria, Research Funding.

scholarly journals Glycosylation Affects Ligand Binding and Function of the Activating Natural Killer Cell Receptor 2B4 (CD244) Protein

2011 ◽  
Vol 286 (27) ◽  
pp. 24142-24149 ◽  
Author(s):  
Stefanie Margraf-Schönfeld ◽  
Carolin Böhm ◽  
Carsten Watzl
Keyword(s):  
Ligand Binding ◽  
Nk Cells ◽  
Natural Killer ◽  
Cell Function ◽  
Nk Cell ◽  
Negative Impact ◽  
Killer Cell ◽  
Target Cells ◽  
Functional Assay ◽  
Cell Responses

2B4 (CD244) is an important activating receptor for the regulation of natural killer (NK) cell responses. Here we show that 2B4 is heavily and differentially glycosylated in primary human NK cells and NK cell lines. The differential glycosylation could be attributed to sialic acid residues on N- and O-linked carbohydrates. Using a recombinant fusion protein of the extracellular domain of 2B4, we demonstrate that N-linked glycosylation of 2B4 is essential for the binding to its ligand CD48. In contrast, sialylation of 2B4 has a negative impact on ligand binding, as the interaction between 2B4 and CD48 is increased after the removal of sialic acids. This was confirmed in a functional assay system, where the desialylation of NK cells or the inhibition of O-linked glycosylation resulted in increased 2B4-mediated lysis of CD48-expressing tumor target cells. These data demonstrate that glycosylation has an important impact on 2B4-mediated NK cell function and suggest that regulated changes in glycosylation during NK cell development and activation might be involved in the regulation of NK cell responses.

scholarly journals The Evolving Knowledge on T and NK Cells in Classic Hodgkin Lymphoma: Insights into Novel Subsets Populating the Immune Microenvironment

Cancers ◽  
2020 ◽  
Vol 12 (12) ◽  
pp. 3757
Author(s):  
Isacco Ferrarini ◽  
Antonella Rigo ◽  
Carlo Visco ◽  
Mauro Krampera ◽  
Fabrizio Vinante
Keyword(s):  
Nk Cells ◽  
Hodgkin Lymphoma ◽  
Nk Cell ◽  
Imaging Techniques ◽  
High Dimensional ◽  
T Helper ◽  
Mass Cytometry ◽  
Immune Microenvironment ◽  
Cell Compartments ◽  
Classic Hodgkin Lymphoma

Classic Hodgkin lymphoma (cHL) is a unique lymphoid neoplasm characterized by extensive immune infiltrates surrounding rare malignant Hodgkin Reed–Sternberg (HRS) cells. Different subsets of T and NK cells have long been recognized in the cHL microenvironment, yet their distinct contribution to disease pathogenesis has remained enigmatic. Very recently, novel platforms for high dimensional analysis of immune cells, such as single-cell RNA sequencing and mass cytometry, have revealed unanticipated insights into the composition of T- and NK-cell compartments in cHL. Advances in imaging techniques have better defined specific T-helper subpopulations physically interacting with neoplastic cells. In addition, the identification of novel cytotoxic subsets with an exhausted phenotype, typically enriched in cHL milieu, is shedding light on previously unrecognized immune evasion mechanisms. This review examines the immunological features and the functional properties of T and NK subsets recently identified in the cHL microenvironment, highlighting their pathological interplay with HRS cells. We also discuss how this knowledge can be exploited to predict response to immunotherapy and to design novel strategies to improve PD-1 blockade efficacy.

scholarly journals 638 Hypoxia reprograms natural killer cells and impairs their therapeutic potential

2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A667-A667
Author(s):  
Philippa Kennedy ◽  
Upasana Sunil Arvindam ◽  
Brianna Ettestad ◽  
Shee Kwan Phung ◽  
Quinlan Kile ◽  
...  
Keyword(s):  
Nk Cells ◽  
Healthy Donor ◽  
Cell Function ◽  
Nk Cell ◽  
Granzyme B ◽  
Differential Expression Analysis ◽  
Mass Cytometry ◽  
Donor Blood ◽  
Oxygen Conditions ◽  
The University

BackgroundNatural killer (NK) cell-based immunotherapies, from biologics to cell products, are being studied in the clinic across many cancer settings. These treatments have had therapeutic success for hematological malignancies but their impact on solid tumors remains limited. To succeed in the solid tumor setting, NK cells must enter the tumor microenvironment, with its low oxygen concentration (hypoxia), and retain functionality. Hypoxia is known to impair NK cell function, but a greater understanding of the mechanisms driving this impairment could lead to improvements in NK cell immunotherapy for solid tumors.MethodsWe used an advanced incubator system: AVATARTM (Xcell biosciences), to finely tune the oxygen conditions in vitro to mimic the physiologic (5–12% oxygen) and hypoxic (1% oxygen) conditions found in vivo. Human NK cells were isolated from healthy donor blood and cultured with a low dose of interleukin 15 for up to 7 days, at 20% oxygen (standard incubator) or at 12%, 5% or 1% oxygen, to replicate the physiological conditions found in blood, bone marrow or hypoxic tumor, respectively. Phenotypes were analyzed by mass cytometry. Confocal and live cell imaging examined the cytotoxic process. Metabolic processes were assessed by flow cytometry and Seahorse assay. RNAseq and ATACseq were performed.ResultsNK cells were capable of natural cytotoxicity and antibody-dependent cellular cytotoxicity at physiological oxygen concentrations (5–20% oxygen), but killing was impaired under hypoxia (1% oxygen). Examination of the cytotoxic process revealed conjugate formation, polarization of granules to the synapse and granule release were not impaired by hypoxia. However, granzyme B (a component of cytotoxic granules) and the death receptor TRAIL were decreased in NK cells exposed to hypoxia (figure 1A). RNAseq revealed upregulation of histone demethylases under hypoxia, with a shift in metabolism and decrease in the cell cycle. Glycolysis was upregulated under hypoxia and there was a concomitant increase in reactive oxygen species. ATACseq revealed profound epigenetic regulation of NK cells exposed to hypoxia, with limited changes occurring in NK cells cultured in 20% oxygen (figure 1B). Activation, adhesion, killing, proliferation and cytokine secretion were all pathways differentially regulated under hypoxia compared to 20% oxygen.ConclusionsNK cells exposed to hypoxia fail to kill tumor cells. Mechanistically, a lack of granzyme B and death receptors contribute to this deficit. ATACseq reveals epigenetic signatures associated with NK cell function that may allow interventions crucial to overcome barriers to solid tumor immunotherapy.AcknowledgementsWe would like to acknowledge the services of the Minnesota Supercomputing Institute, the University Imaging Centers and the University Flow Cytometry Resource, all University of Minnesota.Abstract 638 Figure 1NK cells are altered by exposure to hypoxia. Human NK cells from healthy donor blood were cultured in standard incubators (20% oxygen) or hypoxia (1% oxygen) for 7 days. (A) The relative abundance of granzyme B and TRAIL were compared on these NK cells at day 7 by time of flight mass cytometry. Analyzed by differential expression analysis through Astrolabe Diagnostics. Each line represents a donor. (B) Venn diagram of overlap between ATACseq differential expression analysis peaks. 2,413 regions were open at day 7 compared to day 0, when cultured under hypoxia (red circle); 365 regions were open at day 7 compared to day 0, when cultured in standard incubators (yellow circle).

scholarly journals Sialic Acids and Their Influence on Human NK Cell Function

Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 263
Author(s):  
Philip Rosenstock ◽  
Thomas Kaufmann
Keyword(s):  
Nk Cells ◽  
Immune Cells ◽  
Cell Function ◽  
Nk Cell ◽  
Sialic Acids ◽  
Innate Immune ◽  
Target Cells ◽  
Carbon Backbone ◽  
Nk Cell Receptors ◽  
Cell Inhibition

Sialic acids are sugars with a nine-carbon backbone, present on the surface of all cells in humans, including immune cells and their target cells, with various functions. Natural Killer (NK) cells are cells of the innate immune system, capable of killing virus-infected and tumor cells. Sialic acids can influence the interaction of NK cells with potential targets in several ways. Different NK cell receptors can bind sialic acids, leading to NK cell inhibition or activation. Moreover, NK cells have sialic acids on their surface, which can regulate receptor abundance and activity. This review is focused on how sialic acids on NK cells and their target cells are involved in NK cell function.

scholarly journals The effect of IL-2 stimulation and treatment of TRPM3 on channel co-localisation with PIP2 and NK cell function in myalgic encephalomyelitis/chronic fatigue syndrome patients

2021 ◽  
Vol 19 (1) ◽  
Author(s):  
Natalie Eaton-Fitch ◽  
Hélène Cabanas ◽  
Stanley du Preez ◽  
Donald Staines ◽  
Sonya Marshall-Gradisnik
Keyword(s):  
Chronic Fatigue Syndrome ◽  
Nk Cells ◽  
Cell Function ◽  
Nk Cell ◽  
Chronic Fatigue ◽  
Signalling Pathways ◽  
Cell Cytotoxicity ◽  
Fatigue Syndrome ◽  
Intracellular Signalling Pathways ◽  
Nk Cell Cytotoxicity

Abstract Background Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a serious multifactorial disorder. The origin remains ambiguous, however reduced natural killer (NK) cell cytotoxicity is a consistent immunological feature of ME/CFS. Impaired transient receptor potential melastatin 3 (TRPM3), a phosphatidylinositol dependent channel, and impaired calcium mobilisation have been implicated in ME/CFS pathology. This investigation aimed to examine the localisation of TRPM3 at the NK cell plasma membrane and co-localisation with phosphatidylinositol 4,5-bisphosphate (PIP2). The effect of IL-2 priming and treatment using pregnenolone sulfate (PregS) and ononetin on TRPM3 co-localisation and NK cell cytotoxicity in ME/CFS patients and healthy controls (HC) was also investigated. Methods NK cells were isolated from 15 ME/CFS patients and 15 age- and sex-matched HC. Immunofluorescent technique was used to determine co-localisation of TRPM3 with the NK cell membrane and with PIP2 of ME/CFS patients and HC. Flow cytometry was used to determine NK cell cytotoxicity. Following IL-2 stimulation and treatment with PregS and ononetin changes in co-localisation and NK cell cytotoxicity were measured. Results Overnight treatment of NK cells with PregS and ononetin resulted in reduced co-localisation of TRPM3 with PIP2 and actin in HC. Co-localisation of TRPM3 with PIP2 in NK cells was significantly reduced in ME/CFS patients compared with HC following priming with IL-2. A significant increase in co-localisation of TRPM3 with PIP2 was reported following overnight treatment with ononetin within ME/CFS patients and between groups. Baseline NK cell cytotoxicity was significantly reduced in ME/CFS patients; however, no changes were observed following overnight incubation with IL-2, PregS and ononetin between HC and ME/CFS patients. IL-2 stimulation significantly enhanced NK cell cytotoxicity in HC and ME/CFS patients. Conclusion Significant changes in co-localisation suggest PIP2-dependent TRPM3 function may be impaired in ME/CFS patients. Stimulation of NK cells with IL-2 significantly enhanced cytotoxic function in ME/CFS patients demonstrating normal function compared with HC. A crosstalk exists between IL-2 and TRPM3 intracellular signalling pathways which are dependent on Ca2+ influx and PIP2. While IL-2R responds to IL-2 binding in vitro, Ca2+ dysregulation and impaired intracellular signalling pathways impede NK cell function in ME/CFS patients.

scholarly journals Cytokine-Induced Memory-Like NK Cells with High Reactivity against Acute Leukemia Blasts and Solid Tumor Cells Suitable for Adoptive Immunotherapy Approaches

Cancers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1577
Author(s):  
Matteo Tanzi ◽  
Michela Consonni ◽  
Michela Falco ◽  
Federica Ferulli ◽  
Enrica Montini ◽  
...  
Keyword(s):  
Acute Leukemia ◽  
Nk Cells ◽  
Tumor Cells ◽  
Cell Function ◽  
Nk Cell ◽  
Autologous Tumor ◽  
Lymphoid Leukemia ◽  
Hematopoietic Stem ◽  
Solid Malignancies

The limited efficacy of Natural Killer (NK) cell-based immunotherapy results in part from the suboptimal expansion and persistence of the infused cells. Recent reports suggest that the generation of NK cells with memory-like properties upon in vitro activation with defined cytokines might be an effective way of ensuring long-lasting NK cell function in vivo. Here, we demonstrate that activation with IL-12, IL-15 and IL-18 followed by a one-week culture with optimal doses of Interleukin (IL-2) and IL-15 generates substantial numbers of memory-like NK cells able to persist for at least three weeks when injected into NOD scid gamma (NSG) mice. This approach induces haploidentical donor-derived memory-like NK cells that are highly lytic against patients’ myeloid or lymphoid leukemia blasts, independent of the presence of alloreactive cell populations in the donor and with negligible reactivity against patients’ non-malignant cells. Memory-like NK cells able to lyse autologous tumor cells can also be generated from patients with solid malignancies. The anti-tumor activity of allogenic and autologous memory-like NK cells is significantly greater than that displayed by NK cells stimulated overnight with IL-2, supporting their potential therapeutic value both in patients affected by high-risk acute leukemia after haploidentical hematopoietic stem cell transplantation and in patients with advanced solid malignancies.

Abstract WP319: miRNA Screening of Natural Killer Cell Identifies miR-1224 as a Post-Transcriptional Regulator of NK Cell Function After Ischemic Stroke

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Yan Feng ◽  
Hui Zhao ◽  
Fu-Dong Shi ◽  
Weina Jin
Keyword(s):  
Ischemic Stroke ◽  
Cerebral Ischemia ◽  
Nk Cells ◽  
Expression Profile ◽  
Mirna Expression ◽  
Cell Function ◽  
Nk Cell ◽  
Killer Cell ◽  
Mirna Expression Profile ◽  
Control Group

Objectives: To screen miRNA profile of peripheral NK cells in ischemic stroke mouse model and investigate a most promising candidate (miR-1224) for post-transcriptional regulation of NK cell function after ischemic stroke. Methods: Mice were subjected to a 60 min focal cerebral ischemia produced by transient intraluminal occlusion of MCAO. For NK cell isolation, cell suspensions from the spleens after reperfusion were enriched for NK cells using magnetic-bead sorting system after staining with anti-NK1.1 microbeads. The nCounter Mouse miRNA array was used to analyze miRNA expression profile in splenic NK cells over the time course of experimental ischemic stroke. Based on the miRNA data, we further in vitro modulated miR-1224 in NK cells using mimics or inhibitor, then injected i.v into Rag2-/-γc-/- recipient mice. Neurological function score was compared and spontaneous infection was assessed by pulmonary bacteria colony culture, and changes in potential signaling pathway (SP1/TNF-α) were verified by rt-PCR and western blot. Results: Through miRNA expression profile analysis, we have identified significant changes at each time point in peripheral NK cells after cerebral ischemia. Among all screened miRNA, miR-1224 remarkably increased in MCAO group, which was verified by PCR. Then isolated NK cells treated with mimics or inhibitors, were transferred to Rag2-/-γc-/- recipient mice. Compared with WT mice, Rag2-/-γc-/- mice with miR-1224 inhibitor exhibited increased NK cell number, enhanced NK cell activation/cytotoxicity feature, as well as better neurological behaviors and reduced pulmonary infection after MCAO. Moreover, compared with the control group, NK cells with miR-1224 inhibitor showed significantly increased SP1 gene and protein phosphorylation. As SP1 gene is one of the potential targets of miR-1224, this study suggests that miR-1224 may regulate NK cell function after MCAO, which is associated with SP1 pathway. Conclusion: The miRNA profiling of splenic NK cells provided insight into the functional mechanism and signaling pathways underlying the distinct organ-specific NK cell properties, which will contribute to the better understanding of NK cell mediated immune-response in relation to different stages of stroke.

scholarly journals Interferon Alpha Enhances NK Cell Function and the Suppressive Capacity of HIV-Specific CD8+T Cells

2018 ◽  
Vol 93 (3) ◽  
Author(s):  
Abena K. R. Kwaa ◽  
Chloe A. G. Talana ◽  
Joel N. Blankson
Keyword(s):  
T Cells ◽  
T Cell ◽  
Nk Cells ◽  
Effector Cell ◽  
Cell Function ◽  
Nk Cell ◽  
Suppressive Capacity ◽  
Short Course ◽  
Shock And Kill ◽  
Hiv 1

ABSTRACTCurrent shock-and-kill strategies for the eradication of the HIV-1 reservoir have resulted in blips of viremia but not in a decrease in the size of the latent reservoir in patients on suppressive antiretroviral therapy (ART). This discrepancy could potentially be explained by an inability of the immune system to kill HIV-1-infected cells following the reversal of latency. Furthermore, some studies have suggested that certain latency-reversing agents (LRAs) may inhibit CD8+T cell and natural killer (NK) cell responses. In this study, we tested the hypothesis that alpha interferon (IFN-α) could improve the function of NK cells from chronic progressors (CP) on ART. We show here that IFN-α treatment enhanced cytokine secretion, polyfunctionality, degranulation, and the cytotoxic potential of NK cells from healthy donors (HD) and CP. We also show that this cytokine enhanced the viral suppressive capacity of NK cells from HD and elite controllers or suppressors. Furthermore, IFN-α enhanced global CP CD8+T cell cytokine responses and the suppressive capacity of ES CD8+T cells. Our data suggest that IFN-α treatment may potentially be used as an immunomodulatory agent in HIV-1 cure strategies.IMPORTANCEData suggest that HIV+individuals unable to control infection fail to do so due to impaired cytokine production and/cytotoxic effector cell function. Consequently, the success of cure agendas such as the shock-and-kill strategy will probably depend on enhancing patient effector cell function. In this regard, NK cells are of particular interest since they complement the function of CD8+T cells. Here, we demonstrate the ability of short-course alpha interferon (IFN-α) treatments to effectively enhance such effector functions in chronic progressor NK cells without inhibiting their general CD8+T cell function. These results point to the possibility of exploring such short-course IFN-α treatments for the enhancement of effector cell function in HIV+patients in future cure strategies.

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