scholarly journals Resistance of Janus Kinase-2 Dependent Leptin Signaling in Natural Killer (NK) Cells: A Novel Mechanism of NK Cell Dysfunction in Diet-Induced Obesity

Endocrinology ◽  
2008 ◽  
Vol 149 (7) ◽  
pp. 3370-3378 ◽  
Author(s):  
Heike Nave ◽  
Guenter Mueller ◽  
Britta Siegmund ◽  
Roland Jacobs ◽  
Thorsten Stroh ◽  
...  

Leptin acts not only as an anorexigenic hormone but also regulates cell-mediated immunity via leptin receptors (Ob-R) expressed on T and B lymphocytes. However, the impact of leptin on natural killer (NK) cells is currently elusive. We evaluated leptin effects on NK cells in relation to the body weight in rats using in vivo and in vitro approaches. Leptin was injected iv in male lean and diet-induced obese Lewis and F344 rats. NK cell numbers were analyzed in blood and spleen by fluorescence activated cell sorting and immunohistochemistry, and the activity of NK cells was measured by chromium release assay. Ob-R expression was investigated by confocal laser scanning and quantitative RT-PCR. To compare leptin-dependent intracellular signaling under basal and leptin- and tumor cell (MADB106)-stimulated conditions, intracellular target proteins of NK cells were evaluated by Western blotting. Number and distribution pattern of splenic NK cells were significantly different in lean and obese animals. Leptin administration resulted in a 4-fold higher stimulation of the NK activity in lean than obese animals. This was not due to a decreased expression of Ob-R because quantitative RT-PCR revealed significantly higher Ob-Rb mRNA levels in NK cells from obese rats. In contrast, postreceptor signaling is differentially abrogated in obese animals with significantly lower activation of postreceptor signaling components (Janus kinase-2p, protein kinase B pT308, AMPαpT172) after an in vivo leptin challenge. In conclusion, the results for the first time assign leptin a central role as a modulator of NK cell number and activity only in lean but not obese subjects. The differential role of leptin has important implications for the influence of body weight in the response to systemic inflammations and in the immunological defense of cancer.

2020 ◽  
Vol 8 (Suppl 3) ◽  
pp. A160-A160
Author(s):  
Monica Cho ◽  
Madison Phillips ◽  
Longzhen Song ◽  
Amy Erbe ◽  
Christian Capitini

BackgroundPediatric patients with relapsed and refractory osteosarcoma have poor prognoses with few treatment options. Allogeneic bone marrow transplant (BMT) has not yet shown a graft-versus-tumor (GVT) effect for osteosarcoma. Natural killer (NK) cells demonstrate antitumor activity against osteosarcoma, but adoptively transferred NK cells have limited proliferation, cytotoxicity, and persistence in vivo. To enhance an NK-specific GVT effect, we propose blocking the poliovirus receptor CD155 checkpoint molecule, which is overexpressed on osteosarcoma and can engage both activating and inhibitory receptors on NK cells. The impact of CD155 blockade on GVT and graft-versus-host-disease (GVHD) is unknown.MethodsNK cells from C57BL/6 (B6) mice were expanded with recombinant IL-15/IL-15R and analyzed by flow cytometry. Cytotoxicity assays were performed with IL-15 expanded B6 NK cells and mKate2-expressing K7M2 murine osteosarcoma at a 1:1 ratio with blockade of CD155 and CD155 ligands. To test efficacy of NK cell infusion and CD155 blockade after allogeneic BMT, BALB/c mice were lethally irradiated, transplanted with allogeneic B6 bone marrow, and challenged with luciferase-expressing K7M2 on day 0. At day 7, mice received IL-15 expanded B6 NK cells intravenously with either anti-IgG control or anti-CD155 antibody intraperitoneally and IL-2 subcutaneously on days 7 and 11. Mice were monitored for tumor growth by bioluminescence, and toxicity by GVHD using weight loss and clinical scores.ResultsCompared to unexpanded murine NK cells, IL-15 expanded NK cells (n = 6) show increased expression of NKG2D (65.33 ± 10.77% NKG2D+, p = 0.0077; 1030 ± 177.0 MFI, p = 0.0101) and an increased ratio of the CD155 activating (CD226) to inhibitory (TIGIT) ligand expression (11.71 ± 4.121, p = 0.0362). In cytotoxicity assays with IL-15 expanded allogeneic murine NK cells (n = 3 replicates), CD155 blockade enhances K7M2 osteosarcoma lysis (60.62 ± 3.19%, p = 0.0189) compared to IgG control (29.01 ± 7.66%). CD226 blockade decreased tumor killing (10.62 ± 8.51%, p = 0.0053) compared to CD155 blockade. In vivo allogeneic murine NK cell infusion and anti-CD155 antibody treatment after allogeneic BMT decreased tumor area under the curve by 44.3% compared to IgG control, without exacerbating GVHD.ConclusionsThese findings demonstrate that blockade of CD155 enhances an allogeneic NK cell-specific GVT effect for osteosarcoma treatment without exacerbating GVHD. CD155 blockade has the potential to improve usage of allogeneic BMT and NK cell adoptive immunotherapy as a combination treatment for osteosarcoma, and perhaps other pediatric sarcomas.AcknowledgementsThis work was supported by grants from the National Institute of General Medical Sciences/NIH T32 GM008692 and Training in Cancer Biology Training Grant NIH T32 CA009135 (to MMC), St. Baldrick’s Stand up to Cancer (SU2C) Pediatric Dream Team Translational Research Grant SU2C-AACR-DT-27-17, NCI/NIH R01 CA215461, American Cancer Society Research Scholar Grant RSG- 18-104-01-LIB, and the Midwest Athletes Against Childhood Cancer (MACC) Fund (to CMC). SU2C is a division of the Entertainment Industry Foundation. Research grants are administered by the American Association for Cancer Research, the scientific partner of SU2C. The contents of this article do not necessarily reflect the views or policies of the Department of Health and Human Services, nor does mention of trade names, commercial products, or organizations imply endorsement by the US government.


Blood ◽  
2011 ◽  
Vol 117 (10) ◽  
pp. 2874-2882 ◽  
Author(s):  
Karine Crozat ◽  
Céline Eidenschenk ◽  
Baptiste N. Jaeger ◽  
Philippe Krebs ◽  
Sophie Guia ◽  
...  

Abstract Natural killer (NK) cells are innate immune cells that express members of the leukocyte β2 integrin family in humans and mice. These CD11/CD18 heterodimers play critical roles in leukocyte trafficking, immune synapse formation, and costimulation. The cell-surface expression of one of these integrins, CD11b/CD18, is also recognized as a major marker of mouse NK-cell maturation, but its function on NK cells has been largely ignored. Using N-ethyl-N-nitrosourea (ENU) mutagenesis, we generated a mouse carrying an A → T transverse mutation in the Itgb2 gene, resulting in a mutation that prevented the cell-surface expression of CD18 and its associated CD11a, CD11b, and CD11c proteins. We show that β2 integrin–deficient NK cells have a hyporesponsive phenotype in vitro, and present an alteration of their in vivo developmental program characterized by a selective accumulation of c-kit+ cells. NK-cell missing-self recognition was partially altered in vivo, whereas the early immune response to mouse cytomegalovirus (MCMV) infection occurred normally in CD18-deficient mice. Therefore, β2 integrins are required for optimal NK-cell maturation, but this deficiency is partial and can be bypassed during MCMV infection, highlighting the robustness of antiviral protective responses.


2021 ◽  
Vol 9 (Suppl 3) ◽  
pp. A834-A834
Author(s):  
Xue Yao ◽  
Sandro Matosevic

BackgroundThe effectiveness of natural killer (NK) cell-based immunotherapy against solid tumors is limited by the lack of specific antigens and the immunosuppressive tumor microenvironment (TME). Glioblastoma multiforme (GBM) is one such heavily immunosuppressive tumor that has been particularly hard to target and remains without a viable treatment. The development of novel approaches to enhance the efficacy of NK cells against GBM is urgently needed. NK cell engagers (NKCE) have been developed to enhance the efficacy of NK cell therapy.MethodsTo improve the clinical efficacy of NK cell therapy, we are developing a new generation of multi-specific killer engagers, which consists of a neoantigen-targeting moiety, together with cytokine and chemokine-producing domains. Neoantigens are new antigens formed specifically in tumor cells due to genome mutations, making them highly specific tools to target tumor cells. Our engager has been designed to target Wilms' tumor-1 (WT-1), a highly specific antigen overexpressed in GBM among other solid tumors. This is done through the generation of an scFv specific targeting the complex of WT-1126-134/HLA-A*02:01 on the surface of GBM. On the NK cell side, the engager is designed to target the activating receptor NKp46. Incorporation of the cytokine IL-15 within the engager supports the maturation, persistence, and expansion of NK cells in vivo while favoring their proliferation and survival in the tumor microenvironment. Additionally, our data indicated that the chemokine CXCL10 plays an important role in the infiltration of NK cells into GBM, however, GBM tumors produce low levels of this chemokine. Incorporation of a CXCL10-producing function into our engager supports intratumoral NK cell trafficking by promoting, through their synthetic production, increased levels of CXCL10 locally in the tumor microenvironment.ResultsCollectively, this has resulted in a novel multifunctional NK cell engager, combining neoantigen-cytokine-chemokine elements fused to an activating domain-specific to NK cells, and we have investigated its ability to support and enhance NK cell-mediated cytotoxicity against solid tumors in vitro and in vivo against patient-derived GBM models. The multi-specific engager shows both high tumor specificity, as well as the ability to overcome NK cell dysfunction encountered in the GBM TME.ConclusionsWe hypothesize that taking advantage of our multi-functional engager, NK cells will exhibit superior ex vivo expansion, infiltration, and antitumor activity in the treatment of GBM and other solid tumors.


2021 ◽  
Vol 12 ◽  
Author(s):  
Giorgio Santoni ◽  
Consuelo Amantini ◽  
Matteo Santoni ◽  
Federica Maggi ◽  
Maria Beatrice Morelli ◽  
...  

Natural killer (NK) cells are a main subset of innate lymphocytes that contribute to host immune protection against viruses and tumors by mediating target cell killing and secreting a wide array of cytokines. Their functions are finely regulated by a balance between activating and inhibitory receptors and involve also adhesive interactions. Mechanotransduction is the process in which physical forces sensed by mechanosensors are translated into chemical signaling. Herein, we report findings on the involvement of this mechanism that is mainly mediated by actin cytoskeleton, in the regulation of NK cell adhesion, migration, tissue infiltration and functions. Actin represents the structural basis for NK cell immunological synapse (NKIS) and polarization of secretory apparatus. NK-target cell interaction involves the formation of both uropods and membrane nanotubes that allow target cell interaction over long distances. Actin retrograde flow (ARF) regulates NK cell signaling and controls the equilibrium between activation versus inhibition. Activating NKIS is associated with rapid lamellipodial ARF, whereas lower centripetal actin flow is present during inhibitory NKIS where β actin can associate with the tyrosine phosphatase SHP-1. Overall, a better knowledge of mechanotransduction might represent a future challenge: Realization of nanomaterials tailored for NK cells, would be important to translate in vitro studies in in vivo new immunotherapeutic approaches.


2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii194-ii195
Author(s):  
Nazanin Majd ◽  
Maha Rizk ◽  
Solveig Ericson ◽  
Kris Grzegorzewski ◽  
Sharmila Koppisetti ◽  
...  

Abstract Glioblastoma (GBM) is the most aggressive primary brain tumor with dismal prognosis. Recent advances of immunotherapy in cancer have sparked interest in the use of cell therapy for treatment of GBM. Active transfer of Natural Killer (NK) cells is of particular interest in GBM because NK cells are capable of exerting anti-tumor cytotoxicity without the need for antigen presentation and sensitization, processes that are impaired in GBM. CYNK-001 is an allogeneic, off-the-shelf product enriched for CD56+/CD3- NK cells expanded from placental CD34+ cells manufactured by Celularity. Here, we demonstrate in vitro cytotoxicity of CYNK-001 against several GBM lines and its in vivo anti-tumor activity in a U87MG orthotopic mouse model via intracranial administration resulting in 94.5% maximum reduction in tumor volume. We have developed a phase I window-of-opportunity trial of CYNK-001 in recurrent GBM via intravenous (IV) and intratumoral (IT) routes. In the IV cohort, subjects receive cyclophosphamide for lymphodepletion followed by 3-doses of IV CYNK-001 weekly. In the IT cohort, subjects undergo placement of an IT catheter with an ommaya reservoir followed by 3-doses of IT CYNK-001 weekly. Patients are monitored for 28-days after last infusion for toxicity. Once maximum safe dose (MSD) is determined, patients undergo IV or IT treatments at MSD followed by surgical resection and the tumor tissue will be analyzed for NK cell engraftment and persistence. We will utilize a 3 + 3 dose de-escalation design (maximum n=36). Primary endpoint is safety and feasibility. Secondary endpoints are overall response rate, duration of response, time to progression, progression free survival and overall survival. Main eligibility criteria include age ≥18, KPS ≥60, GBM at first or second relapse with a measurable lesion on ≤2mg dexamethasone. This is the first clinical trial to investigate CYNK-001 in GBM and will lay the foundation for future NK cell therapy in solid tumors.


Blood ◽  
1999 ◽  
Vol 93 (5) ◽  
pp. 1612-1621 ◽  
Author(s):  
Lei Yao ◽  
Cecilia Sgadari ◽  
Keizo Furuke ◽  
Eda T. Bloom ◽  
Julie Teruya-Feldstein ◽  
...  

Abstract Interleukin-12 (IL-12) inhibits angiogenesis in vivo by inducing interferon-γ (IFN-γ) and other downstream mediators. Here, we report that neutralization of natural killer (NK) cell function with antibodies to either asialo GM1 or NK 1.1 reversed IL-12 inhibition of basic fibroblast growth factor (bFGF)-induced angiogenesis in athymic mice. By immunohistochemistry, those sites where bFGF-induced neovascularization was inhibited by IL-12 displayed accumulation of NK cells and the presence of IP-10–positive cells. Based on expression of the cytolytic mediators perforin and granzyme B, the NK cells were locally activated. Experimental Burkitt lymphomas treated locally with IL-12 displayed tumor tissue necrosis, vascular damage, and NK-cell infiltration surrounding small vessels. After activation in vitro with IL-12, NK cells from nude mice became strongly cytotoxic for primary cultures of syngeneic aortic endothelial cells. Cytotoxicity was neutralized by antibodies to IFN-γ. These results document that NK cells are required mediators of angiogenesis inhibition by IL-12, and provide evidence that NK-cell cytotoxicity of endothelial cells is a potential mechanism by which IL-12 can suppress neovascularization.


Cancers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 573 ◽  
Author(s):  
Donal O’Shea ◽  
Andrew E. Hogan

Natural killer (NK) cells are a population of lymphocytes which classically form part of the innate immune system. They are defined as innate lymphocytes, due to their ability to kill infected or transformed cells without prior activation. In addition to their cytotoxic abilities, NK cells are also rapid producers of inflammatory cytokines such as interferon gamma (IFN-γ) and are therefore a critical component of early immune responses. Due to these unique abilities, NK cells are a very important component of host protection, especially anti-tumour and anti-viral immunity. Obesity is a worldwide epidemic, with over 600 million adults and 124 million children now classified as obese. It is well established that individuals who are obese are at a higher risk of many acute and chronic conditions, including cancer and viral infections. Over the past 10 years, many studies have investigated the impact of obesity on NK cell biology, detailing systemic dysregulation of NK cell functions. More recently, several studies have investigated the role of NK cells in the homeostasis of adipose tissue and the pathophysiology of obesity. In this review, we will discuss in detail these studies and focus on emerging data detailing the metabolic mechanisms altering NK cells in obesity.


Blood ◽  
2011 ◽  
Vol 118 (9) ◽  
pp. 2473-2482 ◽  
Author(s):  
Catharina H. M. J. Van Elssen ◽  
Joris Vanderlocht ◽  
Tammy Oth ◽  
Birgit L. M. G. Senden-Gijsbers ◽  
Wilfred T. V. Germeraad ◽  
...  

Abstract Among prostaglandins (PGs), PGE2 is abundantly expressed in various malignancies and is probably one of many factors promoting tumor growth by inhibiting tumor immune surveillance. In the current study, we report on a novel mechanism by which PGE2 inhibits in vitro natural killer–dendritic cell (NK-DC) crosstalk and thereby innate and adaptive immune responses via its effect on NK-DC crosstalk. The presence of PGE2 during IFN-γ/membrane fraction of Klebsiella pneumoniae DC maturation inhibits the production of chemokines (CCL5, CCL19, and CXCL10) and cytokines (IL-12 and IL-18), which is cAMP-dependent and imprinted during DC maturation. As a consequence, these DCs fail to attract NK cells and show a decreased capacity to trigger NK cell IFN-γ production, which in turn leads to reduced T-helper 1 polarization. In addition, the presence of PGE2 during DC maturation impairs DC-mediated augmentation of NK-cell cytotoxicity. Opposed to their inhibitory effects on peripheral blood–derived NK cells, PGE2 matured DCs induce IL-22 secretion of inflammation constraining NKp44+ NK cells present in mucosa-associated lymphoid tissue. The inhibition of NK-DC interaction is a novel regulatory property of PGE2 that is of possible relevance in dampening immune responses in vivo.


Blood ◽  
2005 ◽  
Vol 106 (7) ◽  
pp. 2252-2258 ◽  
Author(s):  
Thierry Walzer ◽  
Marc Dalod ◽  
Scott H. Robbins ◽  
Laurence Zitvogel ◽  
Eric Vivier

AbstractSeveral recent publications have focused on the newly described interactions between natural-killer (NK) cells and dendritic cells (DCs). Activated NK cells induce DC maturation either directly or in synergy with suboptimal levels of microbial signals. Immature DCs appear susceptible to autologous NK-cell-mediated cytolysis while mature DCs are protected. NK-cell-induced DC activation is dependent on both tumor necrosis factor-α (TNF-α)/interferon-γ (IFN-γ) secretion and a cell-cell contact involving NKp30. In vitro, interleukin-12 (IL-12)/IL-18, IL-15, and IFN-α/β production by activated DCs enhance, in turn, NK-cell IFN-γ production, proliferation, and cytotoxic potential, respectively. In vivo, NK-cell/DC interactions may occur in lymphoid organs as well as in nonlymphoid tissues, and their consequences are multiple. By inducing DC activation, NK-cell activation induced by tumor cells can indirectly promote antitumoral T-cell responses. Reciprocally, DCs activated through Toll-like receptors (TLRs) induce potent NK-cell activation in antiviral responses. Thus, DCs and NK cells are equipped with complementary sets of receptors that allow the recognition of various pathogenic agents, emphasizing the role of NK-cell/DC crosstalk in the coordination of innate and adaptive immune responses.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 1310-1310
Author(s):  
Andreas Lundqvist ◽  
Leigh Samsel ◽  
Michael Eckhaus ◽  
Ramaprasad Srinivasan ◽  
Yoshiyuki Takahashi ◽  
...  

Abstract Retrospective data suggest NK cells play a role in protecting recipients from graft versus host disease (GVHD) in the setting of killer IgG-like receptor (KIR) ligand incompatibility. In humans, this protective effect is most evident with MHC mismatched transplantation, usually following in vivo or in vitro T-cell depletion. In MHC mismatched murine transplant models, lethal GVHD is reduced following the adoptive infusion of KIR ligand mismatched NK cells; it is unknown whether NK cells can mediate similar protective effects following MHC matched transplantation. Therefore, we investigated the impact of adoptively infusing KIR ligand mismatched NK cells on GVHD in an MHC matched T-cell replete murine model of allogeneic transplantation. Balb/C recipient mice underwent allogeneic bone marrow (8 x 106 cells) and splenocyte (15 x 106 cells) transplantation from B10.d2 donors following 950cGy of irradiation. Allogeneic B10.d2 donor NK cells were first isolated by negative depletion using magnetic beads selecting for CD4, CD5, CD8a, CD19, Gr-1 and Ter-119, and then expanded over 4-6 days in vitro in DMEM media containing 10% FCS and 500U/ml of IL-2. NK cell subsets (KIR ligand matched vs. KIR ligand mismatched) were then isolated by flow cytometry into Ly49I/C+ NK cells (KIR ligand mismatched in the GVHD direction for Balb/C recipients) and Ly49A/G+ NK cells (KIR ligand matched for Balb/C recipients). On day +4, recipient mice received a single tail vein injection with either KIR ligand matched, KIR ligand mismatched or unsorted “bulk” NK cells (0.5–1.0 x 106 NK cells). All (9/9) control transplant recipients (no adoptive NK cell infusion) as well as recipients of Ly49A/G (KIR ligand matched) NK cells (13/13) developed skin GVHD, in contrast to 4/7 (57%, p=0.03) recipients of bulk NK cells and only a minority (13% [1/8], p < 0.01) of animals receiving KIR ligand mismatched NK cells. Using a cumulative clinical GVHD scoring system (total score = 9), overall GVHD was decreased in recipients of KIR ligand mismatched NK cells (median score = 0 at day +45) compared to mice that received KIR ligand matched NK cells (median score = 3; p = 0.15) or no NK cells (median score = 3; p= 0.12); no significant difference in survival was observed between cohorts. This murine model provides the first in vivo evidence that adoptively infused KIR ligand mismatched allogeneic NK cells reduce GVHD following T-cell replete MHC matched allogeneic transplantation. The impact of infusing multiple doses of KIR ligand mismatched NK cells on GVHD and their ability to induce a graft-vs-tumor effect in tumor bearing Balb/c mice is currently being evaluated.


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