An HLA-I signature favouring KIR-educated Natural Killer cells mediates immune control of HIV in children and contrasts with the HLA-B-restricted CD8+ T-cell-mediated immune control in adults

Natural Killer (NK) cells contribute to HIV control in adults, but HLA-B-mediated T-cell activity has a more substantial impact on disease outcome. However, the HLA-B molecules influencing immune control in adults have less impact on paediatric infection. To investigate the contribution NK cells make to immune control, we studied >300 children living with HIV followed over two decades in South Africa. In children, HLA-B alleles associated with adult protection or disease-susceptibility did not have significant effects, whereas Bw4 (p = 0.003) and low HLA-A expression (p = 0.002) alleles were strongly associated with immunological and viral control. In a comparator adult cohort, Bw4 and HLA-A expression contributions to HIV disease outcome were dwarfed by those of protective and disease-susceptible HLA-B molecules. We next investigated the immunophenotype and effector functions of NK cells in a subset of these children using flow cytometry. Slow progression and better plasma viraemic control were also associated with high frequencies of less terminally differentiated NKG2A+NKp46+CD56dim NK cells strongly responsive to cytokine stimulation and linked with the immunogenetic signature identified. Future studies are indicated to determine whether this signature associated with immune control in early life directly facilitates functional cure in children.

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Peptide-Dependent Recognition of HLA-B*57:01 by KIR3DS1

Journal of Virology ◽

10.1128/jvi.03586-14 ◽

2015 ◽

Vol 89 (10) ◽

pp. 5213-5221 ◽

Cited By ~ 44

Author(s):

Geraldine M. O'Connor ◽

Julian P. Vivian ◽

Emma Gostick ◽

Phillip Pymm ◽

Bernard A. P. Lafont ◽

...

Keyword(s):

Hiv Infection ◽

Nk Cells ◽

Natural Killer ◽

Molecular Mechanisms ◽

Viral Infections ◽

Hla Class I ◽

Class I ◽

Disease Outcome ◽

Immune Control ◽

Peptide Epitopes

ABSTRACTKiller cell immunoglobulin-like receptors (KIRs) play an important role in the activation of natural killer (NK) cells, which in turn contribute to the effective immune control of many viral infections. In the context of HIV infection, the closely related KIR3DL1 and KIR3DS1 molecules, in particular, have been associated with disease outcome. Inhibitory signals via KIR3DL1 are disrupted by downregulation of HLA class I ligands on the infected cell surface and can also be impacted by changes in the presented peptide repertoire. In contrast, the activatory ligands for KIR3DS1 remain obscure. We used a structure-driven approach to define the characteristics of HLA class I-restricted peptides that interact with KIR3DL1 and KIR3DS1. In the case of HLA-B*57:01, we used this knowledge to identify bona fide HIV-derived peptide epitopes with similar properties. Two such peptides facilitated productive interactions between HLA-B*57:01 and KIR3DS1. These data reveal the presence of KIR3DS1 ligands within the HIV-specific peptide repertoire presented by a protective HLA class I allotype, thereby enhancing our mechanistic understanding of the processes that enable NK cells to impact disease outcome.IMPORTANCENatural killer (NK) cells are implicated as determinants of immune control in many viral infections, but the precise molecular mechanisms that initiate and control these responses are unclear. The activating receptor KIR3DS1 in combination with HLA-Bw4 has been associated with better outcomes in HIV infection. However, evidence of a direct interaction between these molecules is lacking. In this study, we demonstrate that KIR3DS1 recognition of HLA-Bw4 is peptide dependent. We also identify HIV-derived peptide epitopes presented by the protective HLA-B*57:01 allotype that facilitate productive interactions with KIR3DS1. Collectively, these findings suggest a mechanism whereby changes in the peptide repertoire associated with viral infection provide a trigger for KIR3DS1 engagement and NK cell activation.

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The Good and the Bad of Natural Killer Cells in Virus Control: Perspective for Anti-HBV Therapy

International Journal of Molecular Sciences ◽

10.3390/ijms20205080 ◽

2019 ◽

Vol 20 (20) ◽

pp. 5080 ◽

Cited By ~ 3

Author(s):

Paola Fisicaro ◽

Marzia Rossi ◽

Andrea Vecchi ◽

Greta Acerbi ◽

Valeria Barili ◽

...

Keyword(s):

T Cells ◽

Chronic Hepatitis ◽

T Cell ◽

Hepatitis B ◽

Nk Cells ◽

Natural Killer ◽

Chronic Hepatitis B ◽

Nk Cell ◽

Viral Control ◽

Cell Functions

Immune modulatory therapies are widely believed to represent potential therapeutic strategies for chronic hepatitis B infection (CHB). Among the cellular targets for immune interventions, Natural Killer (NK) cells represent possible candidates because they have a key role in anti-viral control by producing cytokines and by exerting cytotoxic functions against virus-infected cells. However, in patients with chronic hepatitis B, NK cells have been described to be more pathogenic than protective with preserved cytolytic activity but with a poor capacity to produce anti-viral cytokines. In addition, NK cells can exert a regulatory activity and possibly suppress adaptive immune responses in the setting of persistent viral infections. Consequently, a potential drawback of NK-cell targeted modulatory interventions is that they can potentiate the suppressive NK cell effect on virus-specific T cells, which further causes impairment of exhausted anti-viral T cell functions. Thus, clinically useful NK-cell modulatory strategies should be not only suited to improve positive anti-viral NK cell functions but also to abrogate T cell suppression by NK cell-mediated T cell killing. This review outlines the main NK cell features with a particular focus on CHB infection. It describes different mechanisms involved in NK-T cell interplay as well as how NK cells can have positive anti-viral effector functions and negative suppressive effects on T cells activity. This review discusses how modulation of their balance can have potential therapeutic implications.

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CRISPR-Cas9–Mediated TIM3 Knockout in Human Natural Killer Cells Enhances Growth Inhibitory Effects on Human Glioma Cells

International Journal of Molecular Sciences ◽

10.3390/ijms22073489 ◽

2021 ◽

Vol 22 (7) ◽

pp. 3489

Author(s):

Takayuki Morimoto ◽

Tsutomu Nakazawa ◽

Ryosuke Matsuda ◽

Fumihiko Nishimura ◽

Mitsutoshi Nakamura ◽

...

Keyword(s):

T Cell ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Protein Complexes ◽

Lymphocyte Activation ◽

Exon 2 ◽

Effector Cells ◽

Guide Rna ◽

Human Natural Killer Cells

Glioblastoma (GBM) is the most common and aggressive primary malignant brain tumor in adults. Natural Killer (NK) cells are potent cytotoxic effector cells against tumor cells inducing GBM cells; therefore, NK cell based- immunotherapy might be a promising target in GBM. T cell immunoglobulin mucin family member 3 (TIM3), a receptor expressed on NK cells, has been suggested as a marker of dysfunctional NK cells. We established TIM3 knockout in NK cells, using the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9). Electroporating of TIM3 exon 2- or exon 5-targeting guide RNA- Cas9 protein complexes (RNPs) inhibited TIM3 expression on NK cells with varying efficacy. T7 endonuclease I mutation detection assays showed that both RNPs disrupted the intended genome sites. The expression of other checkpoint receptors, i.e., programmed cell death 1 (PD1), Lymphocyte-activation gene 3 (LAG3), T cell immunoreceptor with Ig and ITIM domains (TIGIT), and TACTILE (CD96) were unchanged on the TIM3 knockout NK cells. Real time cell growth assays revealed that TIM3 knockout enhanced NK cell–mediated growth inhibition of GBM cells. These results demonstrated that TIM3 knockout enhanced human NK cell mediated cytotoxicity on GBM cells. Future, CRISPR-Cas9 mediated TIM3 knockout in NK cells may prove to be a promising immunotherapeutic alternative in patient with GBM.

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Anti-tumor effects of RTX-240: an engineered red blood cell expressing 4-1BB ligand and interleukin-15

Cancer Immunology Immunotherapy ◽

10.1007/s00262-021-03001-7 ◽

2021 ◽

Author(s):

Shannon L. McArdel ◽

Anne-Sophie Dugast ◽

Maegan E. Hoover ◽

Arjun Bollampalli ◽

Enping Hong ◽

...

Keyword(s):

T Cells ◽

T Cell ◽

Blood Cell ◽

Nk Cells ◽

Red Blood Cell ◽

Safety Profile ◽

Nk Cell ◽

Cell Activity ◽

In Vivo Studies

AbstractRecombinant agonists that activate co-stimulatory and cytokine receptors have shown limited clinical anticancer utility, potentially due to narrow therapeutic windows, the need for coordinated activation of co-stimulatory and cytokine pathways and the failure of agonistic antibodies to recapitulate signaling by endogenous ligands. RTX-240 is a genetically engineered red blood cell expressing 4-1BBL and IL-15/IL-15Rα fusion (IL-15TP). RTX-240 is designed to potently and simultaneously stimulate the 4-1BB and IL-15 pathways, thereby activating and expanding T cells and NK cells, while potentially offering an improved safety profile through restricted biodistribution. We assessed the ability of RTX-240 to expand and activate T cells and NK cells and evaluated the in vivo efficacy, pharmacodynamics and tolerability using murine models. Treatment of PBMCs with RTX-240 induced T cell and NK cell activation and proliferation. In vivo studies using mRBC-240, a mouse surrogate for RTX-240, revealed biodistribution predominantly to the red pulp of the spleen, leading to CD8 + T cell and NK cell expansion. mRBC-240 was efficacious in a B16-F10 melanoma model and led to increased NK cell infiltration into the lungs. mRBC-240 significantly inhibited CT26 tumor growth, in association with an increase in tumor-infiltrating proliferating and cytotoxic CD8 + T cells. mRBC-240 was tolerated and showed no evidence of hepatic injury at the highest feasible dose, compared with a 4-1BB agonistic antibody. RTX-240 promotes T cell and NK cell activity in preclinical models and shows efficacy and an improved safety profile. Based on these data, RTX-240 is now being evaluated in a clinical trial.

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miR-1224 contributes to ischemic stroke-mediated natural killer cell dysfunction by targeting Sp1 signaling

Journal of Neuroinflammation ◽

10.1186/s12974-021-02181-4 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Yan Feng ◽

Yan Li ◽

Ying Zhang ◽

Bo-Hao Zhang ◽

Hui Zhao ◽

...

Keyword(s):

Ischemic Stroke ◽

Nk Cells ◽

Natural Killer ◽

Brain Ischemia ◽

Cell Activation ◽

Nk Cell ◽

Cell Activity ◽

Passive Transfer ◽

Immune Defense ◽

Nk Cell Activity

Abstract Background Brain ischemia compromises natural killer (NK) cell-mediated immune defenses by acting on neurogenic and intracellular pathways. Less is known about the posttranscriptional mechanisms that regulate NK cell activation and cytotoxicity after ischemic stroke. Methods Using a NanoString nCounter® miRNA array panel, we explored the microRNA (miRNA) profile of splenic NK cells in mice subjected to middle cerebral artery occlusion. Differential gene expression and function/pathway analysis were applied to investigate the main functions of predicted miRNA target genes. miR-1224 inhibitor/mimics transfection and passive transfer of NK cells were performed to confirm the impact of miR-1224 in NK cells after brain ischemia. Results We observed striking dysregulation of several miRNAs in response to ischemia. Among those miRNAs, miR-1224 markedly increased 3 days after ischemic stroke. Transfection of miR-1224 mimics into NK cells resulted in suppression of NK cell activity, while an miR-1224 inhibitor enhanced NK cell activity and cytotoxicity, especially in the periphery. Passive transfer of NK cells treated with an miR-1224 inhibitor prevented the accumulation of a bacterial burden in the lungs after ischemic stroke, suggesting an enhanced immune defense of NK cells. The transcription factor Sp1, which controls cytokine/chemokine release by NK cells at the transcriptional level, is a predicted target of miR-1224. The inhibitory effect of miR-1224 on NK cell activity was blocked in Sp1 knockout mice. Conclusions These findings indicate that miR-1224 may serve as a negative regulator of NK cell activation in an Sp1-dependent manner; this mechanism may be a novel target to prevent poststroke infection specifically in the periphery and preserve immune defense in the brain.

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Commitment of Common T/Natural Killer (Nk) Progenitors to Unipotent T and Nk Progenitors in the Murine Fetal Thymus Revealed by a Single Progenitor Assay

Journal of Experimental Medicine ◽

10.1084/jem.190.11.1617 ◽

1999 ◽

Vol 190 (11) ◽

pp. 1617-1626 ◽

Cited By ~ 122

Author(s):

Tomokatsu Ikawa ◽

Hiroshi Kawamoto ◽

Shinji Fujimoto ◽

Yoshimoto Katsura

Keyword(s):

T Cell ◽

Nk Cells ◽

Natural Killer ◽

T Cell Receptor ◽

Cell Lineage ◽

Cell Receptor ◽

The Other ◽

Fetal Thymus ◽

Β Chain ◽

Clonal Assay

We have established a new clonal assay system that can evenly support the development of T and natural killer (NK) cells. With this system, we show that all T cell progenitors in the earliest CD44+CD25−FcγRII/III− fetal thymus (FT) cell population retain NK potential, and that the NK lineage–committed progenitors (p-NK) also exist in this population. T cell lineage–committed progenitors (p-T), which are unable to generate NK cells, first appear at the CD44+CD25− FcγRII/III+ stage in day 12 FT. The proportion of p-T markedly increases during the transition from the CD44+CD25− stage to the CD44+CD25+ stage in day 14 FT. On the other hand, p-NK preferentially increase in number at the CD44+CD25− stage between days 12 and 14 of gestation. The production of p-NK continues up to the CD44+CD25+ stage, but ceases before the rearrangement of T cell receptor β chain genes. It was further shown that the CD44+CD25− CD122+ population of day 14 FT exclusively contains p-NK. These results indicate that the earliest T cell progenitor migrating into the FT is T/NK bipotent, and strongly suggest that the bipotent progenitor continuously produces p-NK and p-T until the CD44+CD25+ stage.

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Effect of natural killer cells on syngeneic bone marrow: in vitro and in vivo studies demonstrating graft failure due to NK cells in an identical twin treated by bone marrow transplantation

Blood ◽

10.1182/blood.v66.5.1043.bloodjournal6651043 ◽

1985 ◽

Vol 66 (5) ◽

pp. 1043-1046

Author(s):

GD Goss ◽

MA Wittwer ◽

WR Bezwoda ◽

J Herman ◽

A Rabson ◽

...

Keyword(s):

Bone Marrow ◽

Bone Marrow Transplantation ◽

Aplastic Anemia ◽

Nk Cells ◽

Natural Killer ◽

Marrow Transplantation ◽

Bone Marrow Failure ◽

Cell Activity ◽

High Dose

Bone marrow transplantation for severe idiopathic aplastic anemia was undertaken in a patient, using his monozygotic twin brother as the donor. In spite of the use of syngeneic bone marrow, failure of engraftment occurred on two occasions. In vitro studies demonstrated that natural killer (NK) cells from the recipient markedly inhibited the growth of donor bone marrow granulocyte progenitor cells. On a third attempt, successful bone marrow engraftment was achieved following high-dose cyclophosphamide, which has previously been shown to be inhibitory to NK cells. We conclude that NK cell activity may play an important role in bone marrow failure as well as being responsible for at least some cases of aplastic anemia.

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Role of Cytokines in the Development of Natural Killer (NK) Cells: Bone Marrow Colonies with NK Cell Activity

Natural Killer Cells: Biology and Clinical Application ◽

10.1159/000418923 ◽

2015 ◽

pp. 258-260

Author(s):

Carlo Riccardi ◽

Lorenza Cannarile ◽

Graziella Migliorati

Keyword(s):

Bone Marrow ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Cell Activity ◽

Nk Cell Activity

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Thermal stresses reduce natural killer cell cytotoxicity

Journal of Applied Physiology ◽

10.1152/jappl.1995.79.3.732 ◽

1995 ◽

Vol 79 (3) ◽

pp. 732-737 ◽

Cited By ~ 29

Author(s):

S. J. Won ◽

M. T. Lin

Keyword(s):

Nk Cells ◽

Natural Killer ◽

Target Cell ◽

Nk Cell ◽

Cell Activity ◽

Cortisol Concentration ◽

Target Cells ◽

Nk Cell Activity ◽

Colonic Temperature ◽

Effector Target

The effects of different ambient temperatures (Ta) on the splenic natural killer (NK) cell activity, effector-target cell conjugation activity, and NK cell numbers were assessed in male inbred C3H/HeNCrj mice (7–10 wk old). The splenic NK cytotoxic activities were examined in a 4-h 51Cr release assay in mouse spleen cells that were obtained 1, 2, 4, 8, or 16 days after exposure to Ta of 22, 4, or 35 degrees C. The percentage of conjugating lymphocytes was calculated by counting the number of single lymphocytes bound to single target cells per 400 effector cells. The numbers of NK cells were expressed by the percentage of 5E6-positive cells. The 5E6 identifies only a subset of NK cells. It was found that the splenic NK cell activity, the effector-target cell conjugation activity, or the NK cell number began to fall 1 day after cold (Ta 4 degrees C) or heat (Ta 35 degrees C) stress. After a 16-day period of either cold or heat exposure, the fall in the splenic NK cell activity, the effector-target cell conjugation activity, or the number of 5E6-positive subsets of NK cells was still evident. Compared with those of the control group (Ta 22 degrees C), the cold-stressed mice had higher adrenal cortisol concentration and lower colonic temperature, whereas the heat-stressed animals had higher adrenal cortisol concentration and higher colonic temperature during a 16-day period of thermal exposure. However, neither cold nor heat stress affected both the body weight gain and the spleen weight in our mice.

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