Natural Killer (NK) Cells in Antibacterial Innate Immunity: Angels or Devils?

PubMed Central

Souza-Fonseca-Guimaraes, Fernando; Adib-Conquy, Minou; Cavaillon, Jean-Marc

2012-01-01

Natural killer (NK) cells were first described as immune leukocytes that could kill tumor cells and soon after were reported to kill virus-infected cells. In the mid-1980s, 10 years after their discovery, NK cells were also demonstrated to contribute to the fight against bacterial infection, particularly because of crosstalk with other leukocytes. A wide variety of immune cells are now recognized to interact with NK cells through the production of cytokines such as interleukin (IL)-2, IL-12, IL-15 and IL-18, which boost NK cell activities. The recent demonstration that NK cells express pattern recognition receptors, namely Toll-like and nucleotide oligomerization domain (NOD)-like receptors, led to the understanding that these cells are not only under the control of accessory cells, but can be directly involved in the antibacterial response thanks to their capacity to recognize pathogen-associated molecular patterns. Interferon (IFN)-γ is the predominant cytokine produced by activated NK cells. IFN-γ is a key contributor to antibacterial immune defense. However, in synergy with other inflammatory cytokines, IFN-γ can also lead to deleterious effects similar to those observed during sepsis. Accordingly, as the main source of IFN-γ in the early phase of infection, NK cells display both beneficial and deleterious effects, depending on the circumstances. PMID:22105606

The role of regulatory T cells in the control of natural killer cells: relevance during tumor progression.

PubMed

Ghiringhelli, Francois; Ménard, Cédric; Martin, Francois; Zitvogel, Laurence

2006-12-01

Tumor immunosurveillance relies on cognate immune effectors [lymphocytes and interferon-gamma (IFN-gamma)] and innate immunity [natural killer (NK) cells, natural killer group 2, member D (NKG2D) ligands, perforin/granzyme, and tumor necrosis factor-related apoptosis-inducing ligand]. In parallel, tumor cells promote the expansion of CD4(+)CD25(+) regulatory T cells (Tregs) that counteract T-cell-based anti-tumor immunity. Moreover, accumulating evidence points to a critical role for Tregs in dampening NK cell immune responses. This review summarizes the findings showing that Tregs suppress NK cell effector functions in vitro and in vivo, i.e. homeostatic proliferation, cytotoxicity, and interleukin-12-mediated IFN-gamma production. The molecular mechanism involve selective expression of membrane-bound transforming growth factor-beta on Tregs, which downregulate NKG2D expression on NK cells in vitro and in vivo. The regulatory events dictating NK cell suppression by Tregs have been studied and are discussed. The pathological relevance of the Treg-NK cell interaction has been brought up in tumor models and in patients with cancer. Consequently, inhibition of Tregs through pharmacological interventions should be considered during NK-cell-based immunotherapy of cancer.

Influenza Virus Directly Infects Human Natural Killer Cells and Induces Cell Apoptosis▿

PubMed Central

Mao, Huawei; Tu, Wenwei; Qin, Gang; Law, Helen Ka Wai; Sia, Sin Fun; Chan, Ping-Lung; Liu, Yinping; Lam, Kwok-Tai; Zheng, Jian; Peiris, Malik; Lau, Yu-Lung

2009-01-01

Influenza is an acute respiratory viral disease that is transmitted in the first few days of infection. Evasion of host innate immune defenses, including natural killer (NK) cells, is important for the virus's success as a pathogen of humans and other animals. NK cells encounter influenza viruses within the microenvironment of infected cells and are important for host innate immunity during influenza virus infection. It is therefore important to investigate the direct effects of influenza virus on NK cells. In this study, we demonstrated for the first time that influenza virus directly infects and replicates in primary human NK cells. Viral entry into NK cells was mediated by both clathrin- and caveolin-dependent endocytosis rather than through macropinocytosis and was dependent on the sialic acids on cell surfaces. In addition, influenza virus infection induced a marked apoptosis of NK cells. Our findings suggest that influenza virus can directly target and kill NK cells, a potential novel strategy of influenza virus to evade the NK cell innate immune defense that is likely to facilitate viral transmission and may also contribute to virus pathogenesis. PMID:19587043

The Memories of NK Cells: Innate-Adaptive Immune Intrinsic Crosstalk

PubMed Central

Ortolani, Claudio; del Zotto, Genny; Luchetti, Francesca; Canonico, Barbara; Artico, Marco; Papa, Stefano

2016-01-01

Although NK cells are considered part of the innate immune system, a series of evidences has demonstrated that they possess characteristics typical of the adaptive immune system. These NK adaptive features, in particular their memory-like functions, are discussed from an ontogenetic and evolutionary point of view. PMID:28078307

The Memories of NK Cells: Innate-Adaptive Immune Intrinsic Crosstalk.

PubMed

Gabrielli, Sara; Ortolani, Claudio; Del Zotto, Genny; Luchetti, Francesca; Canonico, Barbara; Buccella, Flavia; Artico, Marco; Papa, Stefano; Zamai, Loris

2016-01-01

Although NK cells are considered part of the innate immune system, a series of evidences has demonstrated that they possess characteristics typical of the adaptive immune system. These NK adaptive features, in particular their memory-like functions, are discussed from an ontogenetic and evolutionary point of view.

The DNA methylation profile of activated human natural killer cells.

PubMed

Wiencke, John K; Butler, Rondi; Hsuang, George; Eliot, Melissa; Kim, Stephanie; Sepulveda, Manuel A; Siegel, Derick; Houseman, E Andres; Kelsey, Karl T

2016-05-03

Natural killer (NK) cells are now recognized to exhibit characteristics akin to cells of the adaptive immune system. The generation of adaptive memory is linked to epigenetic reprogramming including alterations in DNA methylation. The study herein found reproducible genome wide DNA methylation changes associated with human NK cell activation. Activation led predominately to CpG hypomethylation (81% of significant loci). Bioinformatics analysis confirmed that non-coding and gene-associated differentially methylated sites (DMS) are enriched for immune related functions (i.e., immune cell activation). Known DNA methylation-regulated immune loci were also identified in activated NK cells (e.g., TNFA, LTA, IL13, CSF2). Twenty-one loci were designated high priority and further investigated as potential markers of NK activation. BHLHE40 was identified as a viable candidate for which a droplet digital PCR assay for demethylation was developed. The assay revealed high demethylation in activated NK cells and low demethylation in naïve NK, T- and B-cells. We conclude the NK cell methylome is plastic with potential for remodeling. The differentially methylated region signature of activated NKs revealed similarities with T cell activation, but also provided unique biomarker candidates of NK activation, which could be useful in epigenome-wide association studies to interrogate the role of NK subtypes in global methylation changes associated with exposures and/or disease states.

Natural Killer Cell-Based Therapies Targeting Cancer: Possible Strategies to Gain and Sustain Anti-Tumor Activity

PubMed Central

Dahlberg, Carin I. M.; Sarhan, Dhifaf; Chrobok, Michael; Duru, Adil D.; Alici, Evren

2015-01-01

Natural killer (NK) cells were discovered 40 years ago, by their ability to recognize and kill tumor cells without the requirement of prior antigen exposure. Since then, NK cells have been seen as promising agents for cell-based cancer therapies. However, NK cells represent only a minor fraction of the human lymphocyte population. Their skewed phenotype and impaired functionality during cancer progression necessitates the development of clinical protocols to activate and expand to high numbers ex vivo to be able to infuse sufficient numbers of functional NK cells to the cancer patients. Initial NK cell-based clinical trials suggested that NK cell-infusion is safe and feasible with almost no NK cell-related toxicity, including graft-versus-host disease. Complete remission and increased disease-free survival is shown in a small number of patients with hematological malignances. Furthermore, successful adoptive NK cell-based therapies from haploidentical donors have been demonstrated. Disappointingly, only limited anti-tumor effects have been demonstrated following NK cell infusion in patients with solid tumors. While NK cells have great potential in targeting tumor cells, the efficiency of NK cell functions in the tumor microenvironment is yet unclear. The failure of immune surveillance may in part be due to sustained immunological pressure on tumor cells resulting in the development of tumor escape variants that are invisible to the immune system. Alternatively, this could be due to the complex network of immune-suppressive compartments in the tumor microenvironment, including myeloid-derived suppressor cells, tumor-associated macrophages, and regulatory T cells. Although the negative effect of the tumor microenvironment on NK cells can be transiently reverted by ex vivo expansion and long-term activation, the aforementioned NK cell/tumor microenvironment interactions upon reinfusion are not fully elucidated. Within this context, genetic modification of NK cells may provide new possibilities for developing effective cancer immunotherapies by improving NK cell responses and making them less susceptible to the tumor microenvironment. Within this review, we will discuss clinical trials using NK cells with a specific reflection on novel potential strategies, such as genetic modification of NK cells and complementary therapies aimed at improving the clinical outcome of NK cell-based immune therapies. PMID:26648934

Models to Study NK Cell Biology and Possible Clinical Application.

PubMed

Zamora, Anthony E; Grossenbacher, Steven K; Aguilar, Ethan G; Murphy, William J

2015-08-03

Natural killer (NK) cells are large granular lymphocytes of the innate immune system, responsible for direct targeting and killing of both virally infected and transformed cells. NK cells rapidly recognize and respond to abnormal cells in the absence of prior sensitization due to their wide array of germline-encoded inhibitory and activating receptors, which differs from the receptor diversity found in B and T lymphocytes that is due to the use of recombination-activation gene (RAG) enzymes. Although NK cells have traditionally been described as natural killers that provide a first line of defense prior to the induction of adaptive immunity, a more complex view of NK cells is beginning to emerge, indicating they may also function in various immunoregulatory roles and have the capacity to shape adaptive immune responses. With the growing appreciation for the diverse functions of NK cells, and recent technological advancements that allow for a more in-depth understanding of NK cell biology, we can now begin to explore new ways to manipulate NK cells to increase their clinical utility. In this overview unit, we introduce the reader to various aspects of NK cell biology by reviewing topics ranging from NK cell diversity and function, mouse models, and the roles of NK cells in health and disease, to potential clinical applications. © 2015 by John Wiley & Sons, Inc. Copyright © 2015 John Wiley & Sons, Inc.

Role of Natural Killer Cells in the Innate Immune System After Intraportal Islet Transplantation in Mice.

PubMed

Saeki, Y; Ishiyama, K; Ishida, N; Tanaka, Y; Ohdan, H

Both liver natural killer (NK) and NK T cells of the innate immune system play a crucial role in islet graft loss after intraportal islet transplantation, although a relationship between NK and NK T cells in islet loss has not been proven. In this study, we investigated the role of NK cells in the innate immune system in islet graft loss after intraportal islet transplantation. To investigate the involvement of liver NK cells in islet destruction, we assessed the differences in graft survival after intraportal islet transplantation between CD1d -/- diabetic mice and NK cell-depleted CD1d -/- diabetic mice. The transplantation of 400 islets into the liver was sufficient to reverse hyperglycemia in wild-type diabetic mice (100%, 4/4). However, normoglycemia could not be achieved when 200 islets were transplanted (0%, 0/4). In contrast, intraportal transplantation of 200 islets in NK cell-depleted CD1d -/- diabetic mice ameliorated hyperglycemia in 71% of cases (5/7), whereas transplantation of the same number of islets in CD1d -/- diabetic mice did not (0%, 0/4). Histologic findings also confirmed that intact islets were observed in NK cell-depleted CD1d -/- diabetic mice, but were difficult to observe in CD1d -/- diabetic mice. The involvement of liver NK cells in the innate immune system related to islet graft loss after intraportal islet transplantation is revealed by improved graft survival and function in NK cell-depleted CD1d -/- diabetic mice. Our data reveal that regulation of NK cell activity is particularly important when insufficient islet numbers are used for transplantation. Copyright © 2016 Elsevier Inc. All rights reserved.

Ly49 Receptors: Innate and Adaptive Immune Paradigms

PubMed Central

Rahim, Mir Munir A.; Tu, Megan M.; Mahmoud, Ahmad Bakur; Wight, Andrew; Abou-Samra, Elias; Lima, Patricia D. A.; Makrigiannis, Andrew P.

2014-01-01

The Ly49 receptors are type II C-type lectin-like membrane glycoproteins encoded by a family of highly polymorphic and polygenic genes within the mouse natural killer (NK) gene complex. This gene family is designated Klra, and includes genes that encode both inhibitory and activating Ly49 receptors in mice. Ly49 receptors recognize class I major histocompatibility complex-I (MHC-I) and MHC-I-like proteins on normal as well as altered cells. Their functional homologs in humans are the killer cell immunoglobulin-like receptors, which recognize HLA class I molecules as ligands. Classically, Ly49 receptors are described as being expressed on both the developing and mature NK cells. The inhibitory Ly49 receptors are involved in NK cell education, a process in which NK cells acquire function and tolerance toward cells that express “self-MHC-I.” On the other hand, the activating Ly49 receptors recognize altered cells expressing activating ligands. New evidence shows a broader Ly49 expression pattern on both innate and adaptive immune cells. Ly49 receptors have been described on multiple NK cell subsets, such as uterine NK and memory NK cells, as well as NKT cells, dendritic cells, plasmacytoid dendritic cells, macrophages, neutrophils, and cells of the adaptive immune system, such as activated T cells and regulatory CD8+ T cells. In this review, we discuss the expression pattern and proposed functions of Ly49 receptors on various immune cells and their contribution to immunity. PMID:24765094

Acetylcholine-producing NK cells attenuate CNS inflammation via modulation of infiltrating monocytes/macrophages.

PubMed

Jiang, Wei; Li, Daojing; Han, Ranran; Zhang, Chao; Jin, Wei-Na; Wood, Kristofer; Liu, Qiang; Shi, Fu-Dong; Hao, Junwei

2017-07-25

The nonneural cholinergic system of immune cells is pivotal for the maintenance of immunological homeostasis. Here we demonstrate the expression of choline acetyltransferase (ChAT) and cholinergic enzymes in murine natural killer (NK) cells. The capacity for acetylcholine synthesis by NK cells increased markedly under inflammatory conditions such as experimental autoimmune encephalomyelitis (EAE), in which ChAT expression escalated along with the maturation of NK cells. ChAT + and ChAT - NK cells displayed distinctive features in terms of cytotoxicity and chemokine/cytokine production. Transfer of ChAT + NK cells into the cerebral ventricles of CX3CR1 -/- mice reduced brain and spinal cord damage after EAE induction, and decreased the numbers of CNS-infiltrating CCR2 + Ly6C hi monocytes. ChAT + NK cells killed CCR2 + Ly6C hi monocytes directly via the disruption of tolerance and inhibited the production of proinflammatory cytokines. Interestingly, ChAT + NK cells and CCR2 + Ly6C hi monocytes formed immune synapses; moreover, the impact of ChAT + NK cells was mediated by α7-nicotinic acetylcholine receptors. Finally, the NK cell cholinergic system up-regulated in response to autoimmune activation in multiple sclerosis, perhaps reflecting the severity of disease. Therefore, this study extends our understanding of the nonneural cholinergic system and the protective immune effect of acetylcholine-producing NK cells in autoimmune diseases.

TLR-Stimulated Eosinophils Mediate Recruitment and Activation of NK Cells In Vivo.

PubMed

O'Flaherty, S M; Sutummaporn, K; Häggtoft, W L; Worrall, A P; Rizzo, M; Braniste, V; Höglund, P; Kadri, N; Chambers, B J

2017-06-01

Eosinophils like many myeloid innate immune cells can provide cytokines and chemokines for the activation of other immune cells upon TLR stimulation. When TLR-stimulated eosinophils were inoculated i.p. into wild-type mice, and NK cells were rapidly recruited and exhibited antitumour cytotoxicity. However, when mice depleted of CD11c + cells were used, a marked decrease in the number of recruited NK cells was observed. We postulated that CpG or LPS from the injected eosinophils could be transferred to host cells, which in turn could recruit NK cells. However, by inoculating mice deficient in TLR4 or TLR9 with LPS or CpG-stimulated eosinophils respectively, NK cell recruitment was still observed alongside cytotoxicity and IFNγ production. CpG stimulation of eosinophils produced the pro-inflammatory cytokine IL-12 and the chemokine CXCL10, which are important for NK cell activation and recruitment in vivo. To demonstrate the importance of CXCL10 in NK cell recruitment, we found that CpG-stimulated eosinophils pretreated with the gut microbial metabolite butyrate had reduced expression and production of CXCL10 and IL-12 and concomitantly were poor at recruitment of NK cells and inducing IFNγ in NK cells. Therefore, eosinophils like other innate immune cells of myeloid origin can conceivably stimulate NK cell activity. In addition, products of the gut microbiota can be potential inhibitors of NK cell. © 2017 The Foundation for the Scandinavian Journal of Immunology.

Cytotoxic potential of decidual NK cells and CD8+ T cells awakened by infections.

PubMed

Crespo, Ângela C; van der Zwan, Anita; Ramalho-Santos, João; Strominger, Jack L; Tilburgs, Tamara

2017-02-01

To establish a healthy pregnancy the maternal immune system must tolerate fetal allo-antigens, yet remain competent to respond to infections. The ability of decidual NK cells (dNK) to promote migration of fetal extravillous trophoblasts (EVT) and placental growth as well as the capacity of EVT to promote immune tolerance are topics of high interest and extensive research. However, the problem of how dNK and decidual CD8+ T cells (CD8+ dT) provide immunity to infections of the placenta and the mechanisms that regulate their cytolytic function has thus far largely been ignored. Fetal EVT are the most invasive cells of the placenta and directly interact with maternal decidual immune cells at this maternal-fetal interface. Besides the expression of non-polymorphic HLA-E and HLA-G molecules that are associated with immune tolerance, EVT also express highly polymorphic HLA-C molecules that can serve as targets for maternal dNK and CD8+ dT responses. HLA-C expression by EVT has a dual role as the main molecule to which immune tolerance needs to be established and as the only molecule that can present pathogen-derived peptides and provide protective immunity when EVT are infected. The focus of this review is to address the regulation of cytotoxicity of dNK and CD8+ dT, which is essential for maternal-fetal immune tolerance as well as recent evidence that both cell types can provide immunity to infections at the maternal-fetal interface. A particular emphasis is given to the role of HLA-C expressed by EVT and its capacity to elicit dNK and CD8+ dT responses. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Genetic Causes of Human NK Cell Deficiency and Their Effect on NK Cell Subsets

PubMed Central

Mace, Emily M.; Orange, Jordan S.

2016-01-01

Human NK cells play critical roles in human host defense, particularly the control of viral infection and malignancy, and patients with congenital immunodeficiency affecting NK cell function or number can suffer from severe illness. The importance of NK cell function is particularly underscored in patients with primary immunodeficiency in which NK cells are the primary or sole affected population (NK cell deficiency, NKD). While NKD may lead to the absence of NK cells, we are also gaining an increasing appreciation of the effect that NKD may have on the generation of specific NK cell subsets. In turn, this leads to improved insights into the requirements for human NK cell subset generation, as well as their importance in immune homeostasis. The presence of inherently abnormally developed or functionally impaired NK cells, in particular, appears to be problematic in the way of interfering with normal human host defense and may be more impactful than low numbers of NK cells alone. Here, we review the known genetic causes of NKD and the insight that is derived by these into the requirements for human subset generation and, by extension, for NK cell-mediated immunity. PMID:27994588

Involvement of NK cells against tumors and parasites.

PubMed

Papazahariadou, M; Athanasiadis, G I; Papadopoulos, E; Symeonidou, I; Hatzistilianou, M; Castellani, M L; Bhattacharya, K; Shanmugham, L N; Conti, P; Frydas, S

2007-01-01

Host resistance against pathogens depends on a complex interplay of innate and adaptive immune mechanisms. Acting as an early line of defence, the immune system includes activation of neutrophils, tissue macrophages, monocytes, dendritic cells, eosinophils and natural killer (NK) cells. NK cells are lymphoid cells that can be activated without previous stimulation and are therefore like macrophages in the first line of defence against tumor cells and a diverse range of pathogens. NK cells mediate significant activity and produce high levels of proinflammatory cytokines in response to infection. Their cytotoxicity production is induced principally by monocyte-, macrophage- and dendritic cell-derived cytokines, but their activation is also believed to be cytokine-mediated. Recognition of infection by NK cells is accomplished by numerous activating and inhibitory receptors on the NK cells' surface that selectively trigger the cytolytic activity in a major histocompability complex-independent manner. NK cells have trypanocidal activity of fibroblast cells and mediate direct destruction of extracellular epimastigote and trypomastigote forms of T. cruzi and T. lewisi in vitro; moreover, they kill plasmodia-infected erythrocytes directly through cell-cell interaction. This review provides a more detailed analysis of how NK cells recognize and respond to parasites and how they mediate cytotoxicity against tumor cells. Also the unique role of NK cells in innate immunity to infection and the relationship between parasites and carcinogenesis are discussed.

NK cell subsets in autoimmune diseases.

PubMed

Zhang, Cai; Tian, Zhigang

2017-09-01

Natural killer (NK) cells are lymphocytes of the innate immune system. They not only exert cell-mediated cytotoxicity against tumor cells or infected cells, but also play regulatory role through promoting or suppressing functions of other immune cells by secretion of cytokines and chemokines. However, overactivation or dysfunction of NK cells may be associated with pathogenesis of some diseases. NK cells are found to act as a two edged weapon and play opposite roles with both regulatory and inducer activity in autoimmune diseases. Though the precise mechanisms for the opposite effects of NK cells has not been fully elucidated, the importance of NK cells in autoimmune diseases might be associated with different NK cell subsets, different tissue microenvironment and different stages of corresponding diseases. The local tissue microenvironment, unique cellular interactions and different stages of corresponding diseases shape the properties and function of NK cells. In this review, we focus on recent research on the features and function of different NK cell subsets, particularly tissue-resident NK cells in different tissues, and their potential role in autoimmune diseases. Copyright © 2017. Published by Elsevier Ltd.

Natural killer cells in host defense against veterinary pathogens.

PubMed

Shekhar, Sudhanshu; Yang, Xi

2015-11-15

Natural Killer (NK) cells constitute a major subset of innate lymphoid cells that do not express the T- and B-cell receptors and play an important role in antimicrobial defense. NK cells not only induce early and rapid innate immune responses, but also communicate with dendritic cells to shape the adaptive immunity, thus bridging innate and adaptive immunity. Although the functional biology of NK cells is well-documented in a variety of infections in humans and mice, their role in protecting domestic animals from infectious agents is only beginning to be understood. In this article, we summarize the current state of knowledge about the contribution of NK cells in pathogen defense in domestic animals, especially cattle and pigs. Understanding the immunobiology of NK cells will translate into strategies to manipulate these cells for preventive and therapeutic purposes. Copyright © 2015 Elsevier B.V. All rights reserved.

A Systems Biology Approach Reveals that Tissue Tropism to West Nile Virus Is Regulated by Antiviral Genes and Innate Immune Cellular Processes

PubMed Central

Suthar, Mehul S.; Brassil, Margaret M.; Blahnik, Gabriele; McMillan, Aimee; Ramos, Hilario J.; Proll, Sean C.; Belisle, Sarah E.; Katze, Michael G.; Gale, Michael

2013-01-01

The actions of the RIG-I like receptor (RLR) and type I interferon (IFN) signaling pathways are essential for a protective innate immune response against the emerging flavivirus West Nile virus (WNV). In mice lacking RLR or IFN signaling pathways, WNV exhibits enhanced tissue tropism, indicating that specific host factors of innate immune defense restrict WNV infection and dissemination in peripheral tissues. However, the immune mechanisms by which the RLR and IFN pathways coordinate and function to impart restriction of WNV infection are not well defined. Using a systems biology approach, we defined the host innate immune response signature and actions that restrict WNV tissue tropism. Transcriptional profiling and pathway modeling to compare WNV-infected permissive (spleen) and nonpermissive (liver) tissues showed high enrichment for inflammatory responses, including pattern recognition receptors and IFN signaling pathways, that define restriction of WNV replication in the liver. Assessment of infected livers from Mavs−/−×Ifnar−/− mice revealed the loss of expression of several key components within the natural killer (NK) cell signaling pathway, including genes associated with NK cell activation, inflammatory cytokine production, and NK cell receptor signaling. In vivo analysis of hepatic immune cell infiltrates from WT mice demonstrated that WNV infection leads to an increase in NK cell numbers with enhanced proliferation, maturation, and effector action. In contrast, livers from Mavs−/−×Ifnar−/− infected mice displayed reduced immune cell infiltration, including a significant reduction in NK cell numbers. Analysis of cocultures of dendritic and NK cells revealed both cell-intrinsic and -extrinsic roles for the RLR and IFN signaling pathways to regulate NK cell effector activity. Taken together, these observations reveal a complex innate immune signaling network, regulated by the RLR and IFN signaling pathways, that drives tissue-specific antiviral effector gene expression and innate immune cellular processes that control tissue tropism to WNV infection. PMID:23544010

Insufficient natural killer cell responses against retroviruses: how to improve NK cell killing of retrovirus-infected cells.

PubMed

Littwitz-Salomon, Elisabeth; Dittmer, Ulf; Sutter, Kathrin

2016-11-08

Natural killer (NK) cells belong to the innate immune system and protect against cancers and a variety of viruses including retroviruses by killing transformed or infected cells. They express activating and inhibitory receptors on their cell surface and often become activated after recognizing virus-infected cells. They have diverse antiviral effector functions like the release of cytotoxic granules, cytokine production and antibody dependent cellular cytotoxicity. The importance of NK cell activity in retroviral infections became evident due to the discovery of several viral strategies to escape recognition and elimination by NK cells. Mutational sequence polymorphisms as well as modulation of surface receptors and their ligands are mechanisms of the human immunodeficiency virus-1 to evade NK cell-mediated immune pressure. In Friend retrovirus infected mice the virus can manipulate molecular or cellular immune factors that in turn suppress the NK cell response. In this model NK cells lack cytokines for optimal activation and can be functionally suppressed by regulatory T cells. However, these inhibitory pathways can be overcome therapeutically to achieve full activation of NK cell responses and ultimately control dissemination of retroviral infection. One effective approach is to modulate the crosstalk between NK cells and dendritic cells, which produce NK cell-stimulating cytokines like type I interferons (IFN), IL-12, IL-15, and IL-18 upon retrovirus sensing or infection. Therapeutic administration of IFNα directly increases NK cell killing of retrovirus-infected cells. In addition, IL-2/anti-IL-2 complexes that direct IL-2 to NK cells have been shown to significantly improve control of retroviral infection by NK cells in vivo. In this review, we describe novel approaches to improve NK cell effector functions in retroviral infections. Immunotherapies that target NK cells of patients suffering from viral infections might be a promising treatment option for the future.

Interactions between human mesenchymal stem cells and natural killer cells.

PubMed

Sotiropoulou, Panagiota A; Perez, Sonia A; Gritzapis, Angelos D; Baxevanis, Constantin N; Papamichail, Michael

2006-01-01

Mesenchymal stem cells (MSCs) are multipotent progenitor cells representing an attractive therapeutic tool for regenerative medicine. They possess unique immunomodulatory properties, being capable of suppressing T-cell responses and modifying dendritic cell differentiation, maturation, and function, whereas they are not inherently immunogenic, failing to induce alloreactivity to T cells and freshly isolated natural killer (NK) cells. To clarify the generation of host immune responses to implanted MSCs in tissue engineering and their potential use as immunosuppressive elements, the effect of MSCs on NK cells was investigated. We demonstrate that at low NK-to-MSC ratios, MSCs alter the phenotype of NK cells and suppress proliferation, cytokine secretion, and cyto-toxicity against HLA-class I- expressing targets. Some of these effects require cell-to-cell contact, whereas others are mediated by soluble factors, including transforming growth factor-beta1 and prostaglandin E2, suggesting the existence of diverse mechanisms for MSC-mediated NK-cell suppression. On the other hand, MSCs are susceptible to lysis by activated NK cells. Overall, these data improve our knowledge of interactions between MSCs and NK cells and consequently of their effect on innate immune responses and their contribution to the regulation of adaptive immunity, graft rejection, and cancer immunotherapy.

Natural killer (NK) cells inhibit systemic metastasis of glioblastoma cells and have therapeutic effects against glioblastomas in the brain.

PubMed

Lee, Se Jeong; Kang, Won Young; Yoon, Yeup; Jin, Ju Youn; Song, Hye Jin; Her, Jung Hyun; Kang, Sang Mi; Hwang, Yu Kyeong; Kang, Kyeong Jin; Joo, Kyeung Min; Nam, Do-Hyun

2015-12-24

Glioblastoma multiforme (GBM) is characterized by extensive local invasion, which is in contrast with extremely rare systemic metastasis of GBM. Molecular mechanisms inhibiting systemic metastasis of GBM would be a novel therapeutic candidate for GBM in the brain. Patient-derived GBM cells were primarily cultured from surgical samples of GBM patients and were inoculated into the brains of immune deficient BALB/c-nude or NOD-SCID IL2Rgamma(null) (NSG) mice. Human NK cells were isolated from peripheral blood mononucleated cells and expanded in vitro. Patient-derived GBM cells in the brains of NSG mice unexpectedly induced spontaneous lung metastasis although no metastasis was detected in BALB/c-nude mice. Based on the difference of the innate immunity between two mouse strains, NK cell activities of orthotopic GBM xenograft models based on BALB/c-nude mice were inhibited. NK cell inactivation induced spontaneous lung metastasis of GBM cells, which indicated that NK cells inhibit the systemic metastasis. In vitro cytotoxic activities of human NK cells against GBM cells indicated that cytotoxic activity of NK cells against GBM cells prevents systemic metastasis of GBM and that NK cells could be effective cell therapeutics against GBM. Accordingly, NK cells transplanted into orthotopic GBM xenograft models intravenously or intratumorally induced apoptosis of GBM cells in the brain and showed significant therapeutic effects. Our results suggest that innate NK immunity is responsible for rare systemic metastasis of GBM and that sufficient supplementation of NK cells could be a promising immunotherapeutic strategy for GBM in the brain.

Leptin modulates dose-dependently the metabolic and cytolytic activities of NK-92 cells.

PubMed

Lamas, Bruno; Goncalves-Mendes, Nicolas; Nachat-Kappes, Rachida; Rossary, Adrien; Caldefie-Chezet, Florence; Vasson, Marie-Paule; Farges, Marie-Chantal

2013-06-01

Leptin, a hormone-cytokine produced primarily in the adipose tissue, has pleiotropic effects on many biological systems and in several cell types, including immune cells. Hyperleptinemia is associated with immune dysfunction and carcinogenesis. Natural killer (NK) cells are critical mediators of anti-tumor immunity, and leptin receptor deficiency in mice leads to impaired NK function. It was thus decided to explore the in vitro effects of leptin on human NK cell function. NK-92 cells were cultured during 48 h with different leptin concentrations [absence, 10 (physiological), 100 (obesity), or 200 ng/ml (pharmacology)]. Their metabolic activity was assessed using the resazurin test. NK-92 cell cytotoxicity and intracellular IFN-γ production were analyzed by flow cytometry. NK-92 cell mRNA and protein expression levels of cytotoxic effectors were determined by RT-qPCR and Western blot. In our conditions, leptin exerted a dose-dependent stimulatory effect on NK-92 cell metabolic activity. In addition, high leptin concentrations enhanced NK-92 cell cytotoxicity against K562-EGFP and MDA-MB-231-EGFP target cells and inversely reduced cytotoxicity against the MCF-7-EGFP target. At 100 ng/ml, leptin up-regulated both NK cell granzyme B and TRAIL protein expressions and concomitantly down-regulated perforin expression without affecting Fas-L expression. In response to PMA/ionomycin stimulation, the proportion of IFN-γ expressing NK-92 cells increased with 100 and 200 ng/ml of leptin. In conclusion, leptin concentration, at obesity level, variably increased NK-92 cell metabolic activity and modulated NK cell cytotoxicity according to the target cells. The underlying mechanisms are partly due to an up-regulation of TRAIL and IFN-γ expression and a down-regulation of perforin. Copyright © 2012 Wiley Periodicals, Inc.

Baculovirus directly activates murine NK cells via TLR9.

PubMed

Moriyama, T; Suzuki, T; Chang, M O; Kitajima, M; Takaku, H

2017-04-01

The importance of natural killer (NK) cells in innate immune responses against tumors or viral infections enhances the appeal of NK cell-based immunotherapeutic approaches. We have recently reported that baculovirus (BV)-infected dendritic cells (DCs; BV-DCs) induce antitumor immunity against established tumors in mice. These antitumor effects were CD8 + T-cell and NK cell dependent; however, they were found to be CD4 + T-cell independent. In this study, we investigated the involvement of Toll-like receptor 9 (TLR9) in the process of BV recognition by NK cells. We found that BV directly stimulated NK cells, induced the expression of the activation marker CD69 and promoted interferon-gamma (IFN-γ) production and cytotoxicity. Moreover, TLR9 knockout in mice (tlr9-/- NK cells) inhibited NK cell responses to BV, indicating that TLR9 may have a relevant role in the BV-induced upregulation of NK cell functions. Our data demonstrated for the first time that NK cells directly recognize BV via TLR9, which provides opportunities for the use of this technique as an effective tool for BV-based immunotherapies against malignancies.

Impaired NK Cell Responses to Pertussis and H1N1 Influenza Vaccine Antigens in Human Cytomegalovirus-Infected Individuals

PubMed Central

Nielsen, Carolyn M.; White, Matthew J.; Bottomley, Christian; Lusa, Chiara; Rodríguez-Galán, Ana; Turner, Scarlett E. G.; Goodier, Martin R.

2015-01-01

NK cells contribute to postvaccination immune responses after activation by IL-2 from Ag-specific memory T cells or by cross-linking of the low-affinity IgG receptor, CD16, by Ag–Ab immune complexes. Sensitivity of NK cells to these signals from the adaptive immune system is heterogeneous and influenced by their stage of differentiation. CD56dimCD57+ NK cells are less responsive to IL-2 and produce less IFN-γ in response to T cell–mediated activation than do CD56bright or CD56dimCD57− NK cells. Conversely, NK cell cytotoxicity, as measured by degranulation, is maintained across the CD56dim subsets. Human CMV (HCMV), a highly prevalent herpes virus causing lifelong, usually latent, infections, drives the expansion of the CD56dimCD57+NKG2C+ NK cell population, skewing the NK cell repertoire in favor of cytotoxic responses at the expense of cytokine-driven responses. We hypothesized, therefore, that HCMV seropositivity would be associated with altered NK cell responses to vaccine Ags. In a cross-sectional study of 152 U.K. adults, with HCMV seroprevalence rate of 36%, we find that HCMV seropositivity is associated with lower NK cell IFN-γ production and degranulation after in vitro restimulation with pertussis or H1N1 influenza vaccine Ags. Higher expression of CD57/NKG2C and lower expression of IL-18Rα on NK cells from HCMV seropositive subjects do not fully explain these impaired responses, which are likely the result of multiple receptor–ligand interactions. This study demonstrates for the first time, to our knowledge, that HCMV serostatus influences NK cell contributions to adaptive immunity and raises important questions regarding the impact of HCMV infection on vaccine efficacy. PMID:25855356

Insights into seven and single transmembrane-spanning domain receptors and their signaling pathways in human natural killer cells.

PubMed

Maghazachi, Azzam A

2005-09-01

Human natural killer (NK) cells are important cells of the innate immune system. These cells perform two prominent functions: the first is recognizing and destroying virally infected cells and transformed cells; the second is secreting various cytokines that shape up the innate and adaptive immune re-sponses. For these cells to perform these activities, they express different sets of receptors. The receptors used by NK cells to extravasate into sites of injury belong to the seven transmembrane (7TM) family of receptors, which characteristically bind heterotrimeric G proteins. These receptors allow NK cells to sense the chemotactic gradients and activate second messengers, which aid NK cells in polarizing and migrating toward the sites of injured tissues. In addition, these receptors determine how and why human resting NK cells are mainly found in the bloodstream, whereas activated NK cells extravasate into inflammatory sites. Receptors for chemokines and lysophospholipids belong to the 7TM family. On the other hand, NK cells recognize invading or transformed cells through another set of receptors that belong to the single transmembrane-spanning domain family. These receptors are either inhibitory or activating. Inhibitory receptors contain the immune receptor tyrosine-based inhibitory motif, and activating receptors belong to either those that associate with adaptor molecules containing the immune receptor tyrosine-based activating motif (ITAM) or those that associate with adaptor molecules containing motifs other than ITAM. This article will describe the nature of these receptors and examine the intracellular signaling pathways induced in NK cells after ligating both types of receptors. These pathways are crucial for NK cell biology, development, and functions.

Bridging innate NK cell functions with adaptive immunity.

PubMed

Marcenaro, Emanuela; Carlomagno, Simona; Pesce, Silvia; Moretta, Alessandro; Sivori, Simona

2011-01-01

Killer Ig-like receptors (KIRs) are major human NK receptors displaying either inhibitory or activating functions which recognize allotypic determinants of HLA-class I molecules. Surprisingly, NK cell treatment with CpG-ODN (TLR9 ligands) results in selective down-modulation of KIR3DL2, its co-internalization with CpG-ODN and its translocation to TLR9-rich early endosomes. This novel KIR-associated function may offer clues to better understand the possible role of certain KIRs and also emphasizes the involvement of NK cells in the course of microbial infections. NK cells are involved not only in innate immune responses against viruses and tumors but also participate in the complex network of cell-to cell interaction that leads to the development of adaptive immune responses. In this context the interaction of NK cells with DC appears to play a crucial role in the acquisition of CCR7, a chemokine receptor that enables NK cells to migrate towards lymph nodes in response to CCL19 and/or CCL21. Analysis of NK cell clones revealed that KIR-mismatched but not KIR-matched NK cells acquire CCR7. These data have important implications in haploidentical haematopoietic stem cell transplantation (HSCT), in which KIR-mismatched NK cells may acquire the ability to migrate to secondary lymphoid compartments (SLCs), where they can kill recipient's antigen presenting cells (APCs) and T cells thus preventing graft versus host (and host vs. graft) reactions.

Transfer of the human NKG2D ligands UL16 binding proteins (ULBP) 1-3 is related to lytic granule release and leads to ligand retransfer and killing of ULBP-recipient natural killer cells.

PubMed

López-Cobo, Sheila; Romera-Cárdenas, Gema; García-Cuesta, Eva M; Reyburn, Hugh T; Valés-Gómez, Mar

2015-09-01

After immune interactions, membrane fragments can be transferred between cells. This fast transfer of molecules is transient and shows selectivity for certain proteins; however, the constraints underlying acquisition of a protein are unknown. To characterize the mechanism and functional consequences of this process in natural killer (NK) cells, we have compared the transfer of different NKG2D ligands. We show that human NKG2D ligands can be acquired by NK cells with different efficiencies. The main findings are that NKG2D ligand transfer is related to immune activation and receptor-ligand interaction and that NK cells acquire these proteins during interactions with target cells that lead to degranulation. Our results further demonstrate that NK cells that have acquired NKG2D ligands can stimulate activation of autologous NK cells. Surprisingly, NK cells can also re-transfer the acquired molecule to autologous effector cells during this immune recognition that leads to their death. These data demonstrate that transfer of molecules occurs as a consequence of immune recognition and imply that this process might play a role in homeostatic tuning-down of the immune response or be used as marker of interaction. © 2015 John Wiley & Sons Ltd.

Neurokinin-1 receptor agonists bias therapeutic dendritic cells to induce type 1 immunity by licensing host dendritic cells to produce IL-12

PubMed Central

Janelsins, Brian M.; Sumpter, Tina L.; Tkacheva, Olga A.; Rojas-Canales, Darling M.; Erdos, Geza; Mathers, Alicia R.; Shufesky, William J.; Storkus, Walter J.; Falo, Louis D.; Morelli, Adrian E.; Larregina, Adriana T.

2013-01-01

Substance-P and hemokinin-1 are proinflammatory neuropeptides with potential to promote type 1 immunity through agonistic binding to neurokinin-1 receptor (NK1R). Dendritic cells (DCs) are professional antigen-presenting cells that initiate and regulate the outcome of innate and adaptive immune responses. Immunostimulatory DCs are highly desired for the development of positive immunization techniques. DCs express functional NK1R; however, regardless of their potential DC-stimulatory function, the ability of NK1R agonists to promote immunostimulatory DCs remains unexplored. Here, we demonstrate that NK1R signaling activates therapeutic DCs capable of biasing type 1 immunity by inhibition of interleukin-10 (IL-10) synthesis and secretion, without affecting their low levels of IL-12 production. The potent type 1 effector immune response observed following cutaneous administration of NK1R-signaled DCs required their homing in skin-draining lymph nodes (sDLNs) where they induced inflammation and licensed endogenous-conventional sDLN-resident and -recruited inflammatory DCs to secrete IL-12. Our data demonstrate that NK1R signaling promotes immunostimulatory DCs, and provide relevant insight into the mechanisms used by neuromediators to regulate innate and adaptive immune responses. PMID:23365459

The CD94/NKG2C+ NK-cell subset on the edge of innate and adaptive immunity to human cytomegalovirus infection.

PubMed

López-Botet, Miguel; Muntasell, Aura; Vilches, Carlos

2014-04-01

Human cytomegalovirus (HCMV) causes a highly prevalent and lifelong infection, with a multifaceted impact in human health. NK cells play an important role in the immune response to HCMV and the virus has reciprocally developed a variety of immune evasion strategies. We originally reported that HCMV infection promotes, to a variable degree in healthy individuals, a redistribution of the NK-cell receptor (NKR) repertoire which persists under steady-state conditions. Its hallmark is an expansion of a mature NK-cell subset displaying high surface levels of the CD94/NKG2C activating receptor, with additional distinctive phenotypic and functional features. Such adaptation of host NK cells to HCMV infection, confirmed in different clinical settings, is particularly magnified in immunocompromised patients and influenced by NKG2C gene copy number. The mechanism(s) underlying the differentiation and proliferation of NKG2C+ NK cells, the basis for the individual differences in the magnitude of their expansion, and their precise role in anti-viral defence remain open issues. Moreover, the possibility that the impact of HCMV infection on the NK-cell compartment may exert a broader influence on immunity deserves further attention. Copyright © 2014 Elsevier Ltd. All rights reserved.

Natural Killer Cells and Helicobacter pylori Infection: Bacterial Antigens and Interleukin-12 Act Synergistically To Induce Gamma Interferon Production

PubMed Central

Yun, Cheol H.; Lundgren, Anna; Azem, Josef; Sjöling, Åsa; Holmgren, Jan; Svennerholm, Ann-Mari; Lundin, B. Samuel

2005-01-01

Helicobacter pylori is known to induce a local immune response, which is characterized by activation of lymphocytes and the production of IFN-γ in the stomach mucosa. Since not only T cells, but also natural killer (NK) cells, are potent producers of gamma interferon (IFN-γ), we investigated whether NK cells play a role in the immune response to H. pylori infection. Our results showed that NK cells were present in both the gastric and duodenal mucosae but that H. pylori infection did not affect the infiltration of NK cells into the gastrointestinal area. Furthermore, we could show that NK cells could be activated directly by H. pylori antigens, as H. pylori bacteria, as well as lysate from H. pylori, induced the secretion of IFN-γ by NK cells. NK cells were also activated without direct contact when separated from the bacteria by an epithelial cell layer, indicating that the activation of NK cells by H. pylori can also occur in vivo, in the infected stomach mucosa. Moreover, the production of IFN-γ by NK cells was greatly enhanced when a small amount of interleukin-12 (IL-12) was added, and this synergistic effect was associated with increased expression of the IL-12 receptor β2. It was further evident that bacterial lysate alone was sufficient to induce the activation of cytotoxicity-related molecules. In conclusion, we demonstrated that NK cells are present in the gastroduodenal mucosa of humans and that NK cells produce high levels of IFN-γ when stimulated with a combination of H. pylori antigen and IL-12. We propose that NK cells play an active role in the local immune response to H. pylori infection. PMID:15731046

Cognate HLA absence in trans diminishes human NK cell education

PubMed Central

Landtwing, Vanessa; Raykova, Ana; Pezzino, Gaetana; Béziat, Vivien; Graf, Claudine; Moretta, Alessandro; Capaul, Riccarda; Zbinden, Andrea; Malmberg, Karl-Johan; Chijioke, Obinna; Münz, Christian

2016-01-01

NK cells are innate lymphocytes with protective functions against viral infections and tumor formation. Human NK cells carry inhibitory killer cell Ig-like receptors (KIRs), which recognize distinct HLAs. NK cells with KIRs for self-HLA molecules acquire superior cytotoxicity against HLA– tumor cells during education for improved missing-self recognition. Here, we reconstituted mice with human hematopoietic cells from donors with homozygous KIR ligands or with a mix of hematopoietic cells from these homozygous donors, allowing assessment of the resulting KIR repertoire and NK cell education. We found that co-reconstitution with 2 KIR ligand–mismatched compartments did not alter the frequency of KIR-expressing NK cells. However, NK cell education was diminished in mice reconstituted with parallel HLA compartments due to a lack of cognate HLA molecules on leukocytes for the corresponding KIRs. This change in NK cell education in mixed human donor–reconstituted mice improved NK cell–mediated immune control of EBV infection, indicating that mixed hematopoietic cell populations could be exploited to improve NK cell reactivity against leukotropic pathogens. Taken together, these findings indicate that leukocytes lacking cognate HLA ligands can disarm KIR+ NK cells in a manner that may decrease HLA– tumor cell recognition but allows for improved NK cell–mediated immune control of a human γ-herpesvirus. PMID:27571408

Epstein-Barr virus-associated T/natural killer-cell lymphoproliferative disorders.

PubMed

Park, Sanghui; Ko, Young H

2014-01-01

Primary infection with Epstein-Barr virus (EBV) is usually asymptomatic and, in a normal host, EBV remains latent in B cells after primary infection for the remainder of life. Uncommonly, EBV can infect T or natural killer (NK) cells in a person with a defect in innate immunity, and EBV infection can cause unique systemic lymphoproliferative diseases (LPD) of childhood. Primary infection in young children can be complicated by hemophagocytic lymphohistiocytosis or fulminant systemic T-cell LPD of childhood. Uncommonly, patients can develop chronic active EBV (CAEBV) disease-type T/NK LPD, which includes CAEBV infection of the systemic form, hydroa vacciniforme-like T-cell LPD, and mosquito-bite hypersensitivity. The clinical course of CAEBV disease-type T/NK LPD can be smoldering, persistent or progressive, depending on the balance between viral factors and host immunity. Aggressive NK-cell leukemia, hydroa vacciniforme-like T-cell lymphoma, or uncommonly extranodal NK/T-cell lymphoma can develop in children and young adults with CAEBV disease-type T/NK-cell LPD. Extranodal T/NK-cell lymphoma is a disease of adults, and its incidence begins to increase in the third decade and comprises the major subtype of T/NK LPD throughout life. Aggressive NK-cell leukemia and nodal T/NK-cell lymphoma of the elderly are fulminant diseases, and immune senescence may be an important pathogenetic factor. This review describes the current progress in identifying different types of EBV-associated T/NK-cell LPD and includes a brief presentation of data from Korea. © 2014 Japanese Dermatological Association.

Natural Killer Cell Functions during the Innate Immune Response to Pathogenic Streptococci

PubMed Central

Lemire, Paul; Galbas, Tristan; Thibodeau, Jacques; Segura, Mariela

2017-01-01

Dendritic cells (DCs) and NK cells play a crucial role in the first phase of host defense against infections. Group B Streptococcus (GBS) and Streptococcus suis are encapsulated streptococci causing severe systemic inflammation, leading to septicemia and meningitis. Yet, the involvement of NK cells in the innate immune response to encapsulated bacterial infection is poorly characterized. Here, it was observed that these two streptococcal species rapidly induce the release of IFN-γ and that NK cells are the major cell type responsible for this production during the acute phase of the infection. Albeit S. suis capacity to activate NK cells was lower than that of GBS, these cells partially contribute to S. suis systemic infection; mainly through amplification of the inflammatory loop. In contrast, such a role was not observed during GBS systemic infection. IFN-γ release by NK cells required the presence of DCs, which in turn had a synergistic effect on DC cytokine production. These responses were mainly mediated by direct DC-NK cell contact and partially dependent on soluble factors. Though IL-12 and LFA-1 were shown to be critical in S. suis-mediated activation of the DC-NK cell crosstalk, different or redundant molecular pathways modulate DC-NK interactions during GBS infection. The bacterial capsular polysaccharides also differently modulated NK cell activation. Together, these results demonstrated a role of NK cells in the innate immune response against encapsulated streptococcal infections; yet the molecular pathways governing NK activation seem to differ upon the pathogen and should not be generalized when studying bacterial infections. PMID:28706510

Stepwise cytoskeletal polarization as a series of checkpoints in innate but not adaptive cytolytic killing

NASA Astrophysics Data System (ADS)

Wülfing, Christoph; Purtic, Bozidar; Klem, Jennifer; Schatzle, John D.

2003-06-01

Cytolytic killing is a major effector mechanism in the elimination of virally infected and tumor cells. The innate cytolytic effectors, natural killer (NK) cells, and the adaptive effectors, cytotoxic T cells (CTL), despite differential immune recognition, both use the same lytic mechanism, cytolytic granule release. Using live cell video fluorescence microscopy in various primary cell models of NK cell and CTL killing, we show here that on tight target cell contact, a majority of the NK cells established cytoskeletal polarity required for effective lytic function slowly or incompletely. In contrast, CTLs established cytoskeletal polarity rapidly. In addition, NK cell killing was uniquely sensitive to minor interference with cytoskeletal dynamics. We propose that the stepwise NK cell cytoskeletal polarization constitutes a series of checkpoints in NK cell killing. In addition, the use of more deliberate progression to effector function to compensate for inferior immune recognition specificity provides a mechanistic explanation for how the same effector function can be used in the different functional contexts of the innate and adaptive immune response.

Characterization of cytotoxic immune response in skin and mucosal lesions of paracoccidioidomycosis.

PubMed

Pagliari, Carla; Pereira, Naiura Vieira; Kanashiro, Luciane; Stegun, Felipe Weisshaupt; Croda, Julio; Duarte, Maria Irma Seixas; Sotto, Mirian Nacagami

2010-05-01

CD8+ T cells and natural killer (NK) cells are involved in the immune response against some pathogens. For this purpose, we investigated the in situ paracoccidioidomycosis (PCM) immune response addressing the participation of NK cells, CD8+ T cells, perforin and granzyme B expression. Sixty biopsies of PCM skin and mucosa were classified according to the presence of compact granulomas (G1), poorly organized granulomas (G2) and both kinds in the same lesion (G3). CD8+ T cells, NK cells, perforin and granzyme B were showed by immunohistochemistry. CD8+ T cells were increased over NK cells in cutaneous G1 and G2 lesions. There was no difference regarding such cells in G3 lesions, although they were abundant in such lesions. In mucosa, CD8+ T cells were increased in number over NK cells in all groups. Granzyme B in skin increased in G2 and G3. The number of granzyme did not differ in mucosal lesions in the three groups. CD8+ T cells and NK cells play a role in PCM cutaneous and mucosal lesions. The predominance of CD8+ T cells over NK cells may represent an effective response against the fungi. Moreover, the high number of granzyme B expressing cells corroborates this possibility.

MHC-matched induced pluripotent stem cells can attenuate cellular and humoral immune responses but are still susceptible to innate immunity in pigs.

PubMed

Mizukami, Yoshihisa; Abe, Tomoyuki; Shibata, Hiroaki; Makimura, Yukitoshi; Fujishiro, Shuh-hei; Yanase, Kimihide; Hishikawa, Shuji; Kobayashi, Eiji; Hanazono, Yutaka

2014-01-01

Recent studies have revealed negligible immunogenicity of induced pluripotent stem (iPS) cells in syngeneic mice and in autologous monkeys. Therefore, human iPS cells would not elicit immune responses in the autologous setting. However, given that human leukocyte antigen (HLA)-matched allogeneic iPS cells would likely be used for medical applications, a more faithful model system is needed to reflect HLA-matched allogeneic settings. Here we examined whether iPS cells induce immune responses in the swine leukocyte antigen (SLA)-matched setting. iPS cells were generated from the SLA-defined C1 strain of Clawn miniature swine, which were confirmed to develop teratomas in mice, and transplanted into the testes (n = 4) and ovary (n = 1) of C1 pigs. No teratomas were found in pigs on 47 to 125 days after transplantation. A Mixed lymphocyte reaction revealed that T-cell responses to the transplanted MHC-matched (C1) iPS cells were significantly lower compared to allogeneic cells. The humoral immune responses were also attenuated in the C1-to-C1 setting. More importantly, even MHC-matched iPS cells were susceptible to innate immunity, NK cells and serum complement. iPS cells lacked the expression of SLA class I and sialic acids. The in vitro cytotoxic assay showed that C1 iPS cells were targeted by NK cells and serum complement of C1. In vivo, the C1 iPS cells developed larger teratomas in NK-deficient NOG (T-B-NK-) mice (n = 10) than in NK-competent NOD/SCID (T-B-NK+) mice (n = 8) (p<0.01). In addition, C1 iPS cell failed to form teratomas after incubation with the porcine complement-active serum. Taken together, MHC-matched iPS cells can attenuate cellular and humoral immune responses, but still susceptible to innate immunity in pigs.

Human Lymphoid Tissues Harbor a Distinct CD69+CXCR6+ NK Cell Population.

PubMed

Lugthart, Gertjan; Melsen, Janine E; Vervat, Carly; van Ostaijen-Ten Dam, Monique M; Corver, Willem E; Roelen, Dave L; van Bergen, Jeroen; van Tol, Maarten J D; Lankester, Arjan C; Schilham, Marco W

2016-07-01

Knowledge of human NK cells is based primarily on conventional CD56(bright) and CD56(dim) NK cells from blood. However, most cellular immune interactions occur in lymphoid organs. Based on the coexpression of CD69 and CXCR6, we identified a third major NK cell subset in lymphoid tissues. This population represents 30-60% of NK cells in marrow, spleen, and lymph node but is absent from blood. CD69(+)CXCR6(+) lymphoid tissue NK cells have an intermediate expression of CD56 and high expression of NKp46 and ICAM-1. In contrast to circulating NK cells, they have a bimodal expression of the activating receptor DNAX accessory molecule 1. CD69(+)CXCR6(+) NK cells do not express the early markers c-kit and IL-7Rα, nor killer cell Ig-like receptors or other late-differentiation markers. After cytokine stimulation, CD69(+)CXCR6(+) NK cells produce IFN-γ at levels comparable to CD56(dim) NK cells. They constitutively express perforin but require preactivation to express granzyme B and exert cytotoxicity. After hematopoietic stem cell transplantation, CD69(+)CXCR6(+) lymphoid tissue NK cells do not exhibit the hyperexpansion observed for both conventional NK cell populations. CD69(+)CXCR6(+) NK cells constitute a separate NK cell population with a distinct phenotype and function. The identification of this NK cell population in lymphoid tissues provides tools to further evaluate the cellular interactions and role of NK cells in human immunity. Copyright © 2016 by The American Association of Immunologists, Inc.

A High-Throughput Assay for Screening of Natural Products that Enhanced Tumoricidal Activity of NK Cells.

PubMed

Gong, Chenyuan; Ni, Zhongya; Yao, Chao; Zhu, Xiaowen; Ni, Lulu; Wang, Lixin; Zhu, Shiguo

2015-01-01

Recently, immunotherapy has shown a lot of promise in cancer treatment and different immune cell types are involved in this endeavor. Among different immune cell populations, NK cells are also an important component in unleashing the therapeutic activity of immune cells. Therefore, in order to enhance the tumoricidal activity of NK cells, identification of new small-molecule natural products is important. Despite the availability of different screening methods for identification of natural products, a simple, economic and high-throughput method is lacking. Hence, in this study, we have developed a high-throughput assay for screening and indentifying natural products that can enhance NK cell-mediated killing of cancer cells. We expanded human NK cell population from human peripheral blood mononuclear cells (PBMCs) by culturing these PBMCs with membrane-bound IL-21 and CD137L engineered K562 cells. Next, expanded NK cells were co-cultured with non-small cell lung cancer (NSCLC) cells with or without natural products and after 24 h of co-culturing, harvested supernatants were analyzed for IFN-γ secretions by ELISA method. We screened 502 natural products and identified that 28 candidates has the potential to induce IFN-γ secretion by NK cells to varying degrees. Among the 28 natural product candidates, we further confirmed and analyzed the potential of one molecule, andrographolide. It actually increased IFN-γ secretion by NK cells and enhanced NK cell-mediated killing of NSCLC cells. Our results demonstrated that this IFN-γ based high-throughput assay for screening of natural products for NK cell tumoricidal activity is a simple, economic and reliable method.

Plasmacytoid dendritic cells induce NK cell-dependent, tumor antigen-specific T cell cross-priming and tumor regression in mice.

PubMed

Liu, Chengwen; Lou, Yanyan; Lizée, Gregory; Qin, Hong; Liu, Shujuan; Rabinovich, Brian; Kim, Grace J; Wang, Yi-Hong; Ye, Yang; Sikora, Andrew G; Overwijk, Willem W; Liu, Yong-Jun; Wang, Gang; Hwu, Patrick

2008-03-01

A prerequisite for strong adaptive antiviral immunity is the robust initial activation of the innate immune system, which is frequently mediated by TLR-activated plasmacytoid DCs (pDCs). Natural antitumor immunity is often comparatively weak, potentially due to the lack of TLR-mediated activation signals within the tumor microenvironment. To assess whether pDCs are capable of directly facilitating effective antitumor immune responses, mice bearing established subcutaneous B16 melanoma tumors were administered TLR9-activated pDCs directly into the tumor. We found that TLR9-activated pDCs induced robust, spontaneous CTL cross-priming against multiple B16 tumor antigens, leading to the regression of both treated tumors and untreated tumors at distant contralateral sites. This T cell cross-priming was mediated by conventional DCs (cDCs) and was completely dependent upon the early recruitment and activation of NK cells at the tumor site. NK cell recruitment was mediated by CCR5 via chemokines secreted by pDCs, and optimal IFN-gamma production by NK cells was mediated by OX40L expressed by pDCs. Our data thus demonstrated that activated pDCs are capable of initiating effective and systemic antitumor immunity through the orchestration of an immune cascade involving the sequential activation of NK cells, cDCs, and CD8(+) T cells.

Arf-like GTPase Arl8b regulates lytic granule polarization and natural killer cell-mediated cytotoxicity.

PubMed

Tuli, Amit; Thiery, Jerome; James, Ashley M; Michelet, Xavier; Sharma, Mahak; Garg, Salil; Sanborn, Keri B; Orange, Jordan S; Lieberman, Judy; Brenner, Michael B

2013-12-01

Natural killer (NK) lymphocytes contain lysosome-related organelles (LROs), known as lytic granules, which upon formation of immune synapse with the target cell, polarize toward the immune synapse to deliver their contents to the target cell membrane. Here, we identify a small GTP-binding protein, ADP-ribosylation factor-like 8b (Arl8b), as a critical factor required for NK cell-mediated cytotoxicity. Our findings indicate that Arl8b drives the polarization of lytic granules and microtubule-organizing centers (MTOCs) toward the immune synapse between effector NK lymphocytes and target cells. Using a glutathione S-transferase pull-down approach, we identify kinesin family member 5B (KIF5B; the heavy chain of kinesin-1) as an interaction partner of Arl8b from NK cell lysates. Previous studies showed that interaction between kinesin-1 and Arl8b is mediated by SifA and kinesin-interacting protein (SKIP) and the tripartite complex drives the anterograde movement of lysosomes. Silencing of both KIF5B and SKIP in NK cells, similar to Arl8b, led to failure of MTOC-lytic granule polarization to the immune synapse, suggesting that Arl8b and kinesin-1 together control this critical step in NK cell cytotoxicity.

Expansion of NK cells by engineered K562 cells co-expressing 4-1BBL and mMICA, combined with soluble IL-21.

PubMed

Jiang, Bo; Wu, Xuan; Li, Xi-Ning; Yang, Xi; Zhou, Yulai; Yan, Haowei; Wei, An-Hui; Yan, Weiqun

2014-07-01

NK cells hold promise for protecting hosts from cancer and pathogen infection through direct killing and expressing immune-regulatory cytokines. In our study, a genetically modified K562 cell line with surface expression of 4-1BBL and MICA was constructed to expand functional NK cells in vitro for further adoptive immunotherapy against cancer. After a long-term up to 21 day co-culture with newly isolated peripheral blood mononuclear cells (PBMCs) in the presence of soluble IL-21 (sIL-21), notable increase in proportion of expanded NK cells was observed, especially the CD56(bright)CD16(+) subset. Apparent up-regulation of activating receptors CD38, CD69 and NKG2D was detected on expanded NK cells, so did inhibitory receptor CD94; the cytotoxicity of expanded NK cells against target tumor cells exceeded that of NK cells within fresh PBMCs. The intracellular staining showed expanded NK cells produced immune-regulatory IFN-γ. Taken together, we expanded NK cells with significant up-regulation of activating NKG2D and moderate enhancement of cytotoxicity, with IFN-γ producing ability and a more heterogeneous population of NK cells. These findings provide a novel perspective on expanding NK cells in vitro for further biology study and adoptive immunotherapy of NK cells against cancer. Copyright © 2014 Elsevier Inc. All rights reserved.

Bovine colostrum enhances natural killer cell activity and immune response in a mouse model of influenza infection and mediates intestinal immunity through toll-like receptors 2 and 4.

PubMed

Wong, Eric B; Mallet, Jean-François; Duarte, Jairo; Matar, Chantal; Ritz, Barry W

2014-04-01

Oral administration of bovine colostrum affects intestinal immunity, including an increased percentage of natural killer (NK) cells. However, effects on NK cell cytotoxic activity and resistance to infection as well as a potential mechanism remain unclear. Therefore, we investigated the effects of bovine colostrum (La Belle, Inc, Bellingham, WA) on the NK cytotoxic response to influenza infection and on toll-like receptor (TLR) activity in a primary intestinal epithelial cell culture. We hypothesized that colostrum would increase NK cell activity and that TLR-2 and TLR-4 blocking would reduce interleukin 6 production by epithelial cells in response to contact stimulation with colostrum. Four-month-old female C57BL/6 mice were supplemented with 1 g of colostrum per kilogram of body weight before and after infection with influenza A virus (H1N1). Animals were assessed for weight loss, splenic NK cell activity, and lung virus titers. Colostrum-supplemented mice demonstrated less reduction in body weight after influenza infection, indicating a less severe infection, increased NK cell cytotoxicity, and less virus burden in the lungs compared with controls. Colostrum supplementation enhanced NK cell cytotoxicity and improved the immune response to primary influenza virus infection in mice. To investigate a potential mechanism, a primary culture of small intestine epithelial cells was then stimulated with colostrum. Direct activation of epithelial cells resulted in increased interleukin 6 production, which was inhibited with TLR-2 and TLR-4 blocking antibodies. The interaction between colostrum and immunity may be dependent, in part, on the interaction of colostrum components with innate receptors at the intestinal epithelium, including TLR-2 and TLR-4. Copyright © 2014 Elsevier Inc. All rights reserved.

Human cytomegalovirus-induced NKG2C(hi) CD57(hi) natural killer cells are effectors dependent on humoral antiviral immunity.

PubMed

Wu, Zeguang; Sinzger, Christian; Frascaroli, Giada; Reichel, Johanna; Bayer, Carina; Wang, Li; Schirmbeck, Reinhold; Mertens, Thomas

2013-07-01

Recent studies indicate that expansion of NKG2C-positive natural killer (NK) cells is associated with human cytomegalovirus (HCMV); however, their activity in response to HCMV-infected cells remains unclear. We show that NKG2C(hi) CD57(hi) NK cells gated on CD3(neg) CD56(dim) cells can be phenotypically identified as HCMV-induced NK cells that can be activated by HCMV-infected cells. Using HCMV-infected autologous macrophages as targets, we were able to show that these NKG2C(hi) CD57(hi) NK cells are highly responsive to HCMV-infected macrophages only in the presence of HCMV-specific antibodies, whereas they are functionally poor effectors of natural cytotoxicity. We further demonstrate that NKG2C(hi) CD57(hi) NK cells are intrinsically responsive to signaling through CD16 cross-linking. Our findings show that the activity of pathogen-induced innate immune cells can be enhanced by adaptive humoral immunity. Understanding the activity of NKG2C(hi) CD57(hi) NK cells against HCMV-infected cells will be of relevance for the further development of adoptive immunotherapy.

NK cell-released exosomes: Natural nanobullets against tumors.

PubMed

Fais, Stefano

2013-01-01

We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool.

NK cell-released exosomes

PubMed Central

Fais, Stefano

2013-01-01

We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool. PMID:23482694

Is There Natural Killer Cell Memory and Can It Be Harnessed by Vaccination? Natural Killer Cells in Vaccination.

PubMed

Neely, Harold R; Mazo, Irina B; Gerlach, Carmen; von Andrian, Ulrich H

2017-12-18

Natural killer (NK) cells have historically been considered to be a part of the innate immune system, exerting a rapid response against pathogens and tumors in an antigen (Ag)-independent manner. However, over the past decade, evidence has accumulated suggesting that at least some NK cells display certain characteristics of adaptive immune cells. Indeed, NK cells can learn and remember encounters with a variety of Ags, including chemical haptens and viruses. Upon rechallenge, memory NK cells mount potent recall responses selectively to those Ags. This phenomenon, traditionally termed "immunological memory," has been reported in mice, nonhuman primates, and even humans and appears to be concentrated in discrete NK cell subsets. Because immunological memory protects against recurrent infections and is the central goal of active vaccination, it is crucial to define the mechanisms and consequences of NK cell memory. Here, we summarize the different kinds of memory responses that have been attributed to specific NK cell subsets and discuss the possibility to harness NK cell memory for vaccination purposes. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

Expansions of NK-like αβT cells with chronologic aging: Novel lymphocyte effectors that compensate for functional deficits of conventional NK cells and T cells

PubMed Central

Vallejo, Abbe N.; Mueller, Robert G.; Hamel, David L.; Way, Amanda; Dvergsten, Jeffrey A.; Griffin, Patricia; Newman, Anne B.

2010-01-01

As the repertoire of αβT cell receptors (TCR) contracts with advancing age, there is an associated age-dependent accumulation of oligoclonal T cells expressing of a variety of receptors (NKR), normally expressed on natural killer (NK) cells. Evidences for differential regulation of expression of particular NKRs between T cells and NK cells suggest that NKR expression on T cells is physiologically programmed rather than a random event of the aging process. Experimental studies show NKRs on aged αβT cells may function either as independent receptors, and/or as costimulatory receptors to the TCR. Considering the reported deficits of conventional αβTCR-driven activation and also functional deficits of classical NK cells, NKR+ αβT cells likely represent novel immune effectors that are capable of combining innate and adaptive functions. Inasmuch as immunity is a determinant of individual fitness, the type and density of NKRs could be important contributing factors to the wide heterogeneity of health characteristics of older adults, ranging from institutionalized frail elders who are unable to mount immune responses to functionally independent community-dwelling elders who exhibit protective immunity. Understanding the biology of NKR+ αβT cells could lead to new avenues for age-specific intervention to improve protective immunity. PMID:20932941

The influence of macrophages and the tumor microenvironment on natural killer cells.

PubMed

Krneta, T; Gillgrass, A; Ashkar, A A

2013-01-01

Numerous reviews in the field of NK cell biology dictate the pivotal role that NK cells play in tumor rejection. Although these cell types were originally described based on their cytotoxic ability, we now know that NK cells are not naturally born to kill. Both cellular interactions and the local environment in which the NK cell resides in may influence its cytotoxic functions. Just as organ specific NK cells have distinct phenotypic and functional differences, the tumor is a unique microenvironment in itself. The NK cells originally recruited to the tumor site are able to stimulate immune responses and aid in tumor destruction but eventually become persuaded otherwise by mechanisms of immunosuppression. Here, we review potential mechanisms and players involved in NK cell immunosuppression. In particular the effects of another innate immune player, macrophages, will be addressed in augmenting immunosuppression of NK cells within tumors. Tumor-associated macrophages (TAMs) are the main regulatory population of myeloid cells in the tumor and are characterized by their ability to promote tumor cell proliferation and metastasis. In addition, they express/release immunoregulatory factors which have been shown to directly inhibit NK cell function. Understanding how these two cell types interact in the distinct tumor microenvironment will allow us to consider therapies that target TAMs to promote enhanced NK cell activity.

The impact of ageing on natural killer cell function and potential consequences for health in older adults.

PubMed

Hazeldine, Jon; Lord, Janet M

2013-09-01

Forming the first line of defence against virally infected and malignant cells, natural killer (NK) cells are critical effector cells of the innate immune system. With age, significant impairments have been reported in the two main mechanisms by which NK cells confer host protection: direct cytotoxicity and the secretion of immunoregulatory cytokines and chemokines. In elderly subjects, decreased NK cell activity has been shown to be associated with an increased incidence and severity of viral infection, highlighting the clinical implications that age-associated changes in NK cell biology have on the health of older adults. However, is an increased susceptibility to viral infection the only consequence of these age-related changes in NK cell function? Recently, evidence has emerged that has shown that in addition to eliminating transformed cells, NK cells are involved in many other biological processes such as immune regulation, anti-microbial immune responses and the recognition and elimination of senescent cells, novel functions that involve NK-mediated cytotoxicity and/or cytokine production. Thus, the decrease in NK cell function that accompanies physiological ageing is likely to have wider implications for the health of older adults than originally thought. Here, we give a detailed description of the changes in NK cell biology that accompany human ageing and propose that certain features of the ageing process such as: (i) the increased reactivation rates of latent Mycobacterium tuberculosis, (ii) the slower resolution of inflammatory responses and (iii) the increased incidence of bacterial and fungal infection are attributable in part to an age-associated decline in NK cell function. Copyright © 2013 Elsevier B.V. All rights reserved.

Protein Kinase C-θ (PKC-θ) in Natural Killer Cell Function and Anti-Tumor Immunity

PubMed Central

Anel, Alberto; Aguiló, Juan I.; Catalán, Elena; Garaude, Johan; Rathore, Moeez G.; Pardo, Julián; Villalba, Martín

2012-01-01

The protein kinase C-θ (PKCθ), which is essential for T cell function and survival, is also required for efficient anti-tumor immune surveillance. Natural killer (NK) cells, which express PKCθ, play a prominent role in this process, mainly by elimination of tumor cells with reduced or absent major histocompatibility complex class-I (MHC-I) expression. This justifies the increased interest of the use of activated NK cells in anti-tumor immunotherapy in the clinic. The in vivo development of MHC-I-deficient tumors is much favored in PKCθ−/− mice compared with wild-type mice. Recent data offer some clues on the mechanism that could explain the important role of PKCθ in NK cell-mediated anti-tumor immune surveillance: some studies show that PKCθ is implicated in signal transduction and anti-tumoral activity of NK cells elicited by interleukin (IL)-12 or IL-15, while others show that it is implicated in NK cell functional activation mediated by certain killer-activating receptors. Alternatively, the possibility that PKCθ is involved in NK cell degranulation is discussed, since recent data indicate that it is implicated in microtubule-organizing center polarization to the immune synapse in CD4+ T cells. The implication of PKC isoforms in degranulation has been more extensively studied in cytotoxic T lymphocyte, and these studies will be also summarized. PMID:22783260

Decreased NK cell activity after partial vulvectomy in pregnant patient with vulvar intraepithelial neoplasia 3 (VIN3).

PubMed

Jerzak, Malgorzata; Nowakowski, Andrzej; Ohams, Monika; Górski, Andrzej; Baranowsk, Włodzimierz

2017-09-21

The study presents the problem of immune disturbances in pregnant women with vulvar carcinoma in situ (VIN3). NK cell and T reg activity in the study patient were analysed using flow cytometry. Decreased NK cell activity and but increased T reg activity were observed after vulvectomy, with subsequent successful pregnancy outcome. Although vulvar cancer may influence immune cell activity, this issue merits further study.

A cross-sectional study on the relationship of job stress with natural killer cell activity and natural killer cell subsets among healthy nurses.

PubMed

Morikawa, Yuko; Kitaoka-Higashiguchi, Kazuyo; Tanimoto, Chie; Hayashi, Midori; Oketani, Reiko; Miura, Katsuyuki; Nishijo, Muneko; Nakagawa, Hideaki

2005-09-01

The present study investigated the effects of job stress on cellular immune function, such as NK cell activity and NK cell subsets. The participants were 61 female nurses aged 23-59, who worked in a public psychiatric hospital in Ishikawa, Japan. Each subject completed the Nursing Job Stressor Scale (NJSS) and their NK cell activity and lymphocyte surface antigens (CD16+56+) were evaluated as immune system parameters. The NJSS has seven subscales: conflict with other nursing staff, nursing role conflict, conflict with physicians or autonomy, conflict with death or dying, quantitative work load, qualitative work load and conflict with patients. Factors influencing NK cell activity, and the proportion and cell counts of CD16+56+ lymphocytes were evaluated. Increase in quantitative work load significantly decreased NK cell activity. Conversely, no linear relationship was observed between qualitative work load and immunological variables, with the highest percentage of CD16+56+ lymphocytes observed among participants in the medium work load group. The other five NJSS subscales did not relate to immune parameters. In conclusion, the results suggest that perceived job strains, particularly quantitative work load, decreased NK cell function.

Genetically Engineered Natural Killer Cells as a Means for Adoptive Tumor Immunotherapy.

PubMed

Michen, Susanne; Temme, Achim

2016-01-01

Natural killer (NK) cells are lymphoid cells of the innate immune system; they stand at the first defense line against viruses and transformed cells. NK cells use an array of germline-encoded activating and inhibitory receptors that sense virus-infected cells or malignant cells displaying altered surface expression of activating and inhibitory NK cell ligands. They exert potent cytotoxic responses to cellular targets and thus are candidate effector cells for immunotherapy of cancer. In particular, the genetic engineering of NK cells with chimeric antigen receptors (CARs) against surface-expressed tumor-associated antigens (TAAs) seems promising. In the allogeneic context, gene-modified NK cells compared to T cells may be superior because they are short-lived effector cells and do not cause graft-versus-host disease. Furthermore, their anti-tumoral activity can be augmented by combinatorial use with therapeutic antibodies, chemotherapeutics, and radiation. Today, efforts are being undertaken for large-scale NK-cell expansion and their genetic engineering for adoptive cell transfer. With the recent advances in understanding the complex biological interactions that regulate NK cells, it is expected that the genetic engineering of NK cells and a combinatorial blockade of immune evasion mechanisms are required to exploit the full potential of NK-cell-based immunotherapies.

Combined Stimulation with Interleukin-18 and Interleukin-12 Potently Induces Interleukin-8 Production by Natural Killer Cells.

PubMed

Poznanski, Sophie M; Lee, Amanda J; Nham, Tina; Lusty, Evan; Larché, Margaret J; Lee, Dean A; Ashkar, Ali A

2017-01-01

The combination of interleukin (IL)-18 and IL-12 (IL-18+IL-12) potently stimulates natural killer (NK) cells, triggering an innate immune response to infections and cancers. Strategies exploiting the effects of IL-18+IL-12 have shown promise for cancer immunotherapy. However, studies have primarily characterized the NK cell response to IL-18+IL-12 in terms of interferon (IFN)-γ production, with little focus on other cytokines produced. IL-8 plays a critical role in activating and recruiting immune cells, but it also has tumor-promoting functions. IL-8 is classically produced by regulatory NK cells; however, cytotoxic NK cells do not typically produce IL-8. In this study, we uncover that stimulation with IL-18+IL-12 induces high levels of IL-8 production by ex vivo expanded and freshly isolated NK cells and NK cells in peripheral blood mononuclear cells. We further report that tumor necrosis factor (TNF)-α, produced by NK cells following IL-18+IL-12 stimulation, regulates IL-8 production. The IL-8 produced is in turn required for maximal IFN-γ and TNF-α production. These findings may have important implications for the immune response to infections and cancer immunotherapies. This study broadens our understanding of NK cell function and IL-18+IL-12 synergy by uncovering an unprecedented ability of IL-18+IL-12-activated peripheral blood NK cells to produce elevated levels of IL-8 and identifying the requirement for intermediates induced by IL-18+IL-12 for maximal cytokine production following stimulation. © 2017 S. Karger AG, Basel.

Sorafenib paradoxically activates the RAS/RAF/ERK pathway in polyclonal human NK cells during expansion and thereby enhances effector functions in a dose- and time-dependent manner.

PubMed

Lohmeyer, J; Nerreter, T; Dotterweich, J; Einsele, H; Seggewiss-Bernhardt, R

2018-03-24

Natural killer (NK) cells play a major role in host immunity against leukaemia and lymphoma. However, clinical trials applying NK cells have not been as efficient as hoped for. Patients treated with rapidly accelerated fibrosarcoma (RAF) inhibitors exhibit increased tumour infiltration by immune cells, suggesting that a combination of RAF inhibitors with immunotherapy might be beneficial. As mitogen-activated protein kinases (MAPKs) such as raf-1 proto-oncogene, serine/threonine kinase (CRAF) regulate NK cell functions, we performed an in-vitro investigation on the potential of clinically relevant short-acting tyrosine kinase inhibitors (TKIs) as potential adjuvants for NK cell therapy: NK cells from healthy human blood donors were thus treated with sorafenib, sunitinib or the pan-RAF inhibitor ZM336372 during ex-vivo expansion. Functional outcomes assessed after washout of the drugs included cytokine production, degranulation, cytotoxicity, apoptosis induction and signal transduction with/without target cell contact. Paradoxically, sorafenib enhanced NK cell effector functions in a time- and dose-dependent manner by raising the steady-state activation level. Of note, this did not lead to NK cell exhaustion, but enhanced activity against target cells such as K562 or Daudis mediated via the RAS/RAF/extracellular-regulated kinase (ERK) pathway, but not via protein kinase B (AKT). Our data will pave the path to develop a rationale for the considered use of RAF inhibitors such as sorafenib for pre-activation in NK cell-based adoptive immune therapy. © 2018 British Society for Immunology.

Immune and hemorheological changes in Chronic Fatigue Syndrome

PubMed Central

2010-01-01

Background Chronic Fatigue Syndrome (CFS) is a multifactorial disorder that affects various physiological systems including immune and neurological systems. The immune system has been substantially examined in CFS with equivocal results, however, little is known about the role of neutrophils and natural killer (NK) phenotypes in the pathomechanism of this disorder. Additionally the role of erythrocyte rheological characteristics in CFS has not been fully expounded. The objective of this present study was to determine deficiencies in lymphocyte function and erythrocyte rheology in CFS patients. Methods Flow cytometric measurements were performed for neutrophil function, lymphocyte numbers, NK phenotypes (CD56dimCD16+ and CD56brightCD16-) and NK cytotoxic activity. Erythrocyte aggregation, deformability and fibrinogen levels were also assessed. Results CFS patients (n = 10) had significant decreases in neutrophil respiratory burst, NK cytotoxic activity and CD56brightCD16- NK phenotypes in comparison to healthy controls (n = 10). However, hemorheological characteristic, aggregation, deformability, fibrinogen, lymphocyte numbers and CD56dimCD16+ NK cells were similar between the two groups. Conclusion These results indicate immune dysfunction as potential contributors to the mechanism of CFS, as indicated by decreases in neutrophil respiratory burst, NK cell activity and NK phenotypes. Thus, immune cell function and phenotypes may be important diagnostic markers for CFS. The absence of rheological changes may indicate no abnormalities in erythrocytes of CFS patients. PMID:20064266

Dual targeting of glioblastoma with chimeric antigen receptor-engineered natural killer cells overcomes heterogeneity of target antigen expression and enhances antitumor activity and survival.

PubMed

Genßler, Sabrina; Burger, Michael C; Zhang, Congcong; Oelsner, Sarah; Mildenberger, Iris; Wagner, Marlies; Steinbach, Joachim P; Wels, Winfried S

2016-04-01

Epidermal growth factor receptor (EGFR) and its mutant form EGFRvIII are overexpressed in a large proportion of glioblastomas (GBM). Immunotherapy with an EGFRvIII-specific vaccine has shown efficacy against GBM in clinical studies. However, immune escape by antigen-loss variants and lack of control of EGFR wild-type positive clones limit the usefulness of this approach. Chimeric antigen receptor (CAR)-engineered natural killer (NK) cells may represent an alternative immunotherapeutic strategy. For targeting to GBM, we generated variants of the clinically applicable human NK cell line NK-92 that express CARs carrying a composite CD28-CD3ζ domain for signaling, and scFv antibody fragments for cell binding either recognizing EGFR, EGFRvIII, or an epitope common to both antigens. In vitro analysis revealed high and specific cytotoxicity of EGFR-targeted NK-92 against established and primary human GBM cells, which was dependent on EGFR expression and CAR signaling. EGFRvIII-targeted NK-92 only lysed EGFRvIII-positive GBM cells, while dual-specific NK cells expressing a cetuximab-based CAR were active against both types of tumor cells. In immunodeficient mice carrying intracranial GBM xenografts either expressing EGFR, EGFRvIII or both receptors, local treatment with dual-specific NK cells was superior to treatment with the corresponding monospecific CAR NK cells. This resulted in a marked extension of survival without inducing rapid immune escape as observed upon therapy with monospecific effectors. Our results demonstrate that dual targeting of CAR NK cells reduces the risk of immune escape and suggest that EGFR/EGFRvIII-targeted dual-specific CAR NK cells may have potential for adoptive immunotherapy of glioblastoma.

VEGFR2-targeted fusion antibody improved NK cell-mediated immunosurveillance against K562 cells.

PubMed

Ren, Xueyan; Xie, Wei; Wang, Youfu; Xu, Menghuai; Liu, Fang; Tang, Mingying; Li, Chenchen; Wang, Min; Zhang, Juan

2016-08-01

MHC class I polypeptide-related sequence A (MICA), which is normally expressed on cancer cells, activates NK cells via NK group 2-member D pathway. However, some cancer cells escape NK-mediated immune surveillance by shedding membrane MICA causing immune suppression. To address this issue, we designed an antibody-MICA fusion targeting tumor-specific antigen (vascular endothelial growth factor receptor 2, VEGFR2) based on our patented antibody (mAb04) against VEGFR2. In vitro results demonstrate that the fusion antibody retains both the antineoplastic and the immunomodulatory activity of mAb04. Further, we revealed that it enhanced NK-mediated immunosurveillance against K562 cells through increasing degranulation and cytokine production of NK cells. The overall data suggest our new fusion protein provides a promising approach for cancer-targeted immunotherapy and has prospects for potential application of chronic myeloid leukemia.

NK Cell–Mediated Antitumor Effects of a Folate-Conjugated Immunoglobulin are Enhanced by Cytokines

PubMed Central

Kondadasula, SriVidya; Skinner, Cassandra C.; Mundy-Bosse, Bethany L.; Luedke, Eric; Jones, Natalie B.; Mani, Aruna; Roda, Julie; Karpa, Volodymyr; Li, Hong; Li, Jilong; Elavazhagan, Saranya; La Perle, Krista M.; Schmitt, Alessandra C.; Lu, Yanhui; Zhang, Xiaoli; Pan, Xueliang; Mao, Hsaioyin; Davis, Melanie; Jarjoura, David; Butchar, Jonathan P.; Poi, Ming; Phelps, Mitch; Tridandapani, Susheela; Byrd, John C.; Caligiuri, Michael A.; Lee, Robert J.; Carson, William E.

2016-01-01

Optimally effective antitumor therapies would not only activate immune effector cells, but engage them at the tumor. Folate-conjugated to immunoglobulin (F-IgG) could direct innate immune cells with Fc receptors to folate receptor–expressing cancer cells. F-IgG bound to human KB and HeLa cells, as well as murine L1210JF, a folate receptor (FR) overexpressing cancer cell line, as determined by flow cytometry. Recognition of F-IgG by NK cell Fc receptors led to phosphorylation of the ERK transcription factor and increased NK cell expression of CD69. Lysis of KB tumor cells by NK cells increased about 5-fold after treatment with F-IgG, an effect synergistically enhanced by treatment with IL2, IL12, IL15, or IL21 (P < 0.001). F-IgG also enhanced the lysis of chronic lymphocytic leukemia cells by autologous NK cells. NK cells significantly increased production of IFNγ, MIP-1α, and RANTES in response to F-IgG–coated KB target cells in the presence of the NK cell–activating cytokine IL12, and these coculture supernatants induced significant T cell chemotaxis P < 0.001). F-IgG–coated targets also stimulated FcR-mediated monocyte effector functions. Studies in a murine leukemia model confirmed the intratumoral localization and antitumor activity of F-IgG, as well as enhancement of its effects by IL12 (P = 0.05). The antitumor effect of this combination was dependent on NK cells and led to decreased tumor cell proliferation in vivo. Thus, F-IgG can induce an immune response against FR-positive tumor cells that is mediated by NK cells and can be augmented by cytokine therapy. PMID:26865456

Natural killer cells regulate T cell immune responses in primary biliary cirrhosis.

PubMed

Shimoda, Shinji; Hisamoto, Satomi; Harada, Kenichi; Iwasaka, Sho; Chong, Yong; Nakamura, Minoru; Bekki, Yuki; Yoshizumi, Tomoharu; Shirabe, Ken; Ikegami, Toru; Maehara, Yoshihiko; He, Xiao-Song; Gershwin, M Eric; Akashi, Koichi

2015-12-01

The hallmark of primary biliary cirrhosis (PBC) is the presence of autoreactive T- and B-cell responses that target biliary epithelial cells (BECs). Biliary cell cytotoxicity is dependent upon initiation of innate immune responses followed by chronic adaptive, as well as bystander, mechanisms. Critical to these mechanisms are interactions between natural killer (NK) cells and BECs. We have taken advantage of the ability to isolate relatively pure viable preparations of liver-derived NK cells, BECs, and endothelial cells, and studied interactions between NK cells and BECs and focused on the mechanisms that activate autoreactive T cells, their dependence on interferon (IFN)-γ, and expression of BEC major histocompatibility complex (MHC) class I and II molecules. Here we show that at a high NK/BEC ratio, NK cells are cytotoxic for autologous BECs, but are not dependent on autoantigen, yet still activate autoreactive CD4(+) T cells in the presence of antigen presenting cells. In contrast, at a low NK/BEC ratio, BECs are not lysed, but IFN-γ production is induced, which facilitates expression of MHC class I and II molecules on BEC and protects them from lysis upon subsequent exposure to autoreactive NK cells. Furthermore, IFN-γ secreted from NK cells after exposure to autologous BECs is essential for this protective function and enables autoreactive CD4(+) T cells to become cytopathic. NK cell-mediated innate immune responses are likely critical at the initial stage of PBC, but also facilitate and maintain the chronic cytopathic effect of autoantigen-specific T cells, essential for progression of disease. © 2015 by the American Association for the Study of Liver Diseases.

Arf-like GTPase Arl8b regulates lytic granule polarization and natural killer cell–mediated cytotoxicity

PubMed Central

Tuli, Amit; Thiery, Jerome; James, Ashley M.; Michelet, Xavier; Sharma, Mahak; Garg, Salil; Sanborn, Keri B.; Orange, Jordan S.; Lieberman, Judy; Brenner, Michael B.

2013-01-01

Natural killer (NK) lymphocytes contain lysosome-related organelles (LROs), known as lytic granules, which upon formation of immune synapse with the target cell, polarize toward the immune synapse to deliver their contents to the target cell membrane. Here, we identify a small GTP-binding protein, ADP-ribosylation factor-like 8b (Arl8b), as a critical factor required for NK cell–mediated cytotoxicity. Our findings indicate that Arl8b drives the polarization of lytic granules and microtubule-organizing centers (MTOCs) toward the immune synapse between effector NK lymphocytes and target cells. Using a glutathione S-transferase pull-down approach, we identify kinesin family member 5B (KIF5B; the heavy chain of kinesin-1) as an interaction partner of Arl8b from NK cell lysates. Previous studies showed that interaction between kinesin-1 and Arl8b is mediated by SifA and kinesin-interacting protein (SKIP) and the tripartite complex drives the anterograde movement of lysosomes. Silencing of both KIF5B and SKIP in NK cells, similar to Arl8b, led to failure of MTOC-lytic granule polarization to the immune synapse, suggesting that Arl8b and kinesin-1 together control this critical step in NK cell cytotoxicity. PMID:24088571

MicroRNA-29b mediates altered innate immune development in acute leukemia

PubMed Central

Mundy-Bosse, Bethany L.; Scoville, Steven D.; Chen, Li; McConnell, Kathleen; Mao, Hsiaoyin C.; Ahmed, Elshafa H.; Zorko, Nicholas; Harvey, Sophia; Cole, Jordan; Zhang, Xiaoli; Costinean, Stefan; Croce, Carlo M.; Larkin, Karilyn; Byrd, John C.; Vasu, Sumithira; Blum, William; Yu, Jianhua; Freud, Aharon G.; Caligiuri, Michael A.

2016-01-01

Natural killer (NK) cells can have potent antileukemic activity following haplo-mismatched, T cell–depleted stem cell transplantations for the treatment of acute myeloid leukemia (AML), but they are not successful in eradicating de novo AML. Here, we have used a mouse model of de novo AML to elucidate the mechanisms by which AML evades NK cell surveillance. NK cells in leukemic mice displayed a marked reduction in the cytolytic granules perforin and granzyme B. Further, as AML progressed, we noted the selective loss of an immature subset of NK cells in leukemic mice and in AML patients. This absence was not due to elimination by cell death or selective reduction in proliferation, but rather to the result of a block in NK cell differentiation. Indeed, NK cells from leukemic mice and humans with AML showed lower levels of TBET and EOMES, transcription factors that are critical for terminal NK cell differentiation. Further, the microRNA miR-29b, a regulator of T-bet and EOMES, was elevated in leukemic NK cells. Finally, deletion of miR-29b in NK cells reversed the depletion of this NK cell subset in leukemic mice. These results indicate that leukemic evasion of NK cell surveillance occurs through miR-mediated dysregulation of lymphocyte development, representing an additional mechanism of immune escape in cancer. PMID:27775550

Tissue-resident natural killer (NK) cells are cell lineages distinct from thymic and conventional splenic NK cells

PubMed Central

Sojka, Dorothy K; Plougastel-Douglas, Beatrice; Yang, Liping; Pak-Wittel, Melissa A; Artyomov, Maxim N; Ivanova, Yulia; Zhong, Chao; Chase, Julie M; Rothman, Paul B; Yu, Jenny; Riley, Joan K; Zhu, Jinfang; Tian, Zhigang; Yokoyama, Wayne M

2014-01-01

Natural killer (NK) cells belong to the innate immune system; they can control virus infections and developing tumors by cytotoxicity and producing inflammatory cytokines. Most studies of mouse NK cells, however, have focused on conventional NK (cNK) cells in the spleen. Recently, we described two populations of liver NK cells, tissue-resident NK (trNK) cells and those resembling splenic cNK cells. However, their lineage relationship was unclear; trNK cells could be developing cNK cells, related to thymic NK cells, or a lineage distinct from both cNK and thymic NK cells. Herein we used detailed transcriptomic, flow cytometric, and functional analysis and transcription factor-deficient mice to determine that liver trNK cells form a distinct lineage from cNK and thymic NK cells. Taken together with analysis of trNK cells in other tissues, there are at least four distinct lineages of NK cells: cNK, thymic, liver (and skin) trNK, and uterine trNK cells. DOI: http://dx.doi.org/10.7554/eLife.01659.001 PMID:24714492

In-Vitro Induced Immunosuppression in a Rotary Cell Culture System

NASA Technical Reports Server (NTRS)

Grimm, Elizabeth A.

1998-01-01

The function of the innate immune system is to provide a first-line of defense against infectious organisms, via control of bacterial and viral growth using antigen nonspecific means. These nonspecific immune effectors include macrophages and Natural Killing (NK) cells, and certain cytokines elicited in response to "super antigens" on the infectious agents. This innate system usually keeps most infectious agents from rapidly growing while the adaptive immune system is generating a specific response complete with immunologic memory. Compelling evidence suggests that space flight results in various immunosuppressive effects, including reduced innate and adaptive immune responses. We were particularly concerned with reduced NK activity at landing, and have asked whether the microgravity component of space flight could be responsible for the previously observed NK defect. We have conclusively demonstrated that simulated microgravity as provided by the Synthecon bioreactors does not inhibit the NK function nor the IL-2 activation of lymphokine-activated killing (LAK). Interleukin-2 is the key cytokine responsible for activation of NK cells to express LAK, as well as to support differentiation of lymphocytes during adaptive immune responses. Therefore, we have disproved our original hypothesis based on poor NK in many of the astronauts upon landing.

Antigen presenting cell-mediated expansion of human umbilical cord blood yields log-scale expansion of natural killer cells with anti-myeloma activity.

PubMed

Shah, Nina; Martin-Antonio, Beatriz; Yang, Hong; Ku, Stephanie; Lee, Dean A; Cooper, Laurence J N; Decker, William K; Li, Sufang; Robinson, Simon N; Sekine, Takuya; Parmar, Simrit; Gribben, John; Wang, Michael; Rezvani, Katy; Yvon, Eric; Najjar, Amer; Burks, Jared; Kaur, Indreshpal; Champlin, Richard E; Bollard, Catherine M; Shpall, Elizabeth J

2013-01-01

Natural killer (NK) cells are important mediators of anti-tumor immunity and are active against several hematologic malignancies, including multiple myeloma (MM). Umbilical cord blood (CB) is a promising source of allogeneic NK cells but large scale ex vivo expansion is required for generation of clinically relevant CB-derived NK (CB-NK) cell doses. Here we describe a novel strategy for expanding NK cells from cryopreserved CB units using artificial antigen presenting feeder cells (aAPC) in a gas permeable culture system. After 14 days, mean fold expansion of CB-NK cells was 1848-fold from fresh and 2389-fold from cryopreserved CB with >95% purity for NK cells (CD56(+)/CD3(-)) and less than 1% CD3(+) cells. Though surface expression of some cytotoxicity receptors was decreased, aAPC-expanded CB-NK cells exhibited a phenotype similar to CB-NK cells expanded with IL-2 alone with respect to various inhibitory receptors, NKG2C and CD94 and maintained strong expression of transcription factors Eomesodermin and T-bet. Furthermore, CB-NK cells formed functional immune synapses with and demonstrated cytotoxicity against various MM targets. Finally, aAPC-expanded CB-NK cells showed significant in vivo activity against MM in a xenogenic mouse model. Our findings introduce a clinically applicable strategy for the generation of highly functional CB-NK cells which can be used to eradicate MM.

The Impact of HLA Class I-Specific Killer Cell Immunoglobulin-Like Receptors on Antibody-Dependent Natural Killer Cell-Mediated Cytotoxicity and Organ Allograft Rejection.

PubMed

Rajalingam, Raja

2016-01-01

Natural killer (NK) cells of the innate immune system are cytotoxic lymphocytes that play an important roles following transplantation of solid organs and hematopoietic stem cells. Recognition of self-human leukocyte antigen (HLA) class I molecules by inhibitory killer cell immunoglobulin-like receptors (KIRs) is involved in the calibration of NK cell effector capacities during the developmental stage, allowing the subsequent recognition and elimination of target cells with decreased expression of self-HLA class I (due to virus infection or tumor transformation) or HLA class I disparities (in the setting of allogeneic transplantation). NK cells expressing an inhibitory KIR-binding self-HLA can be activated when confronted with allografts lacking a ligand for the inhibitory receptor. Following the response of the adaptive immune system, NK cells can further destroy allograft endothelium by antibody-dependent cell-mediated cytotoxicity (ADCC), triggered through cross-linking of the CD16 Fc receptor by donor-specific antibodies bound to allograft. Upon recognizing allogeneic target cells, NK cells also secrete cytokines and chemokines that drive maturation of dendritic cells to promote cellular and humoral adaptive immune responses against the allograft. The cumulative activating and inhibitory signals generated by ligation of the receptors regulates mature NK cell killing of target cells and their production of cytokines and chemokines. This review summarizes the role of NK cells in allograft rejection and proposes mechanistic concepts that indicate a prominent role for KIR-HLA interactions in facilitating NK cells for Fc receptor-mediated ADCC effector function involved in antibody-mediated rejection of solid organ transplants.

Chemokine Receptor Expression on Normal Blood CD56+ NK-Cells Elucidates Cell Partners That Comigrate during the Innate and Adaptive Immune Responses and Identifies a Transitional NK-Cell Population

PubMed Central

Queirós, Maria Luís; Gonçalves, Marta; Fonseca, Sónia; Moura, João

2015-01-01

Studies of chemokine receptors (CKR) in natural killer- (NK-) cells have already been published, but only a few gave detailed information on its differential expression on blood NK-cell subsets. We report on the expression of the inflammatory and homeostatic CKR on normal blood CD56+low CD16+ and CD56+high  CD16−/+low NK-cells. Conventional CD56+low and CD56+high NK-cells present in the normal PB do express CKR for inflammatory cytokines, although with different patterns CD56+low NK-cells are mainly CXCR1/CXCR2+ and CXCR3/CCR5−/+, whereas mostly CD56+high NK-cells are CXCR1/CXCR2− and CXCR3/CCR5+. Both NK-cell subsets have variable CXCR4 expression and are CCR4− and CCR6−. The CKR repertoire of the CD56+low NK-cells approaches to that of neutrophils, whereas the CKR repertoire of the CD56+high NK-cells mimics that of Th1+ T cells, suggesting that these cells are prepared to migrate into inflamed tissues at different phases of the immune response. In addition, we describe a subpopulation of NK-cells with intermediate levels of CD56 expression, which we named CD56+int NK-cells. These NK-cells are CXCR3/CCR5+, they have intermediate levels of expression of CD16, CD62L, CD94, and CD122, and they are CD57− and CD158a−. In view of their phenotypic features, we hypothesize that they correspond to a transitional stage, between the well-known CD56+high and CD56+low NK-cells populations. PMID:26543875

Activated Tissue-Resident Mesenchymal Stromal Cells Regulate Natural Killer Cell Immune and Tissue-Regenerative Function.

PubMed

Petri, Robert Michael; Hackel, Alexander; Hahnel, Katrin; Dumitru, Claudia Alexandra; Bruderek, Kirsten; Flohe, Stefanie B; Paschen, Annette; Lang, Stephan; Brandau, Sven

2017-09-12

The interaction of mesenchymal stromal cells (MSCs) with natural killer (NK) cells is traditionally thought of as a static inhibitory model, whereby resting MSCs inhibit NK cell effector function. Here, we use a dynamic in vitro system of poly(I:C) stimulation to model the interaction of NK cells and tissue-resident MSCs in the context of infection or tissue injury. The experiments suggest a time-dependent system of regulation and feedback, where, at early time points, activated MSCs secrete type I interferon to enhance NK cell effector function, while at later time points TGF-β and IL-6 limit NK cell effector function and terminate inflammatory responses by induction of a regulatory senescent-like NK cell phenotype. Importantly, feedback of these regulatory NK cells to MSCs promotes survival, proliferation, and pro-angiogenic properties. Our data provide additional insight into the interaction of stromal cells and innate immune cells and suggest a model of time-dependent MSC polarization and licensing. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Effects of HIV infection and ART on phenotype and function of circulating monocytes, natural killer, and innate lymphoid cells.

PubMed

Nabatanzi, Rose; Cose, Stephen; Joloba, Moses; Jones, Sarah Rowland; Nakanjako, Damalie

2018-03-15

HIV infection causes upregulation of markers of inflammation, immune activation and apoptosis of host adaptive, and innate immune cells particularly monocytes, natural killer (NK) and innate lymphoid cells (ILCs). Although antiretroviral therapy (ART) restores CD4 T-cell counts, the persistent aberrant activation of monocytes, NK and ILCs observed likely contributes to the incomplete recovery of T-cell effector functions. A better understanding of the effects of HIV infection and ART on the phenotype and function of circulating monocytes, NK, and ILCs is required to guide development of novel therapeutic interventions to optimize immune recovery.

Dacarbazine-mediated upregulation of NKG2D ligands on tumor cells activates NK and CD8 T cells and restrains melanoma growth.

PubMed

Hervieu, Alice; Rébé, Cédric; Végran, Frédérique; Chalmin, Fanny; Bruchard, Mélanie; Vabres, Pierre; Apetoh, Lionel; Ghiringhelli, François; Mignot, Grégoire

2013-02-01

Dacarbazine (DTIC) is a cytotoxic drug widely used for melanoma treatment. However, the putative contribution of anticancer immune responses in the efficacy of DTIC has not been evaluated. By testing how DTIC affects host immune responses to cancer in a mouse model of melanoma, we unexpectedly found that both natural killer (NK) and CD8(+) T cells were indispensable for DTIC therapeutic effect. Although DTIC did not directly affect immune cells, it triggered the upregulation of NKG2D ligands on tumor cells, leading to NK cell activation and IFNγ secretion in mice and humans. NK cell-derived IFNγ subsequently favored upregulation of major histocompatibility complex class I molecules on tumor cells, rendering them sensitive to cytotoxic CD8(+) T cells. Accordingly, DTIC markedly enhanced cytotoxic T lymphocyte antigen 4 inhibition efficacy in vivo in an NK-dependent manner. These results underscore the immunogenic properties of DTIC and provide a rationale to combine DTIC with immunotherapeutic agents that relieve immunosuppression in vivo.

Low Circulating Natural Killer Cell Counts are Associated With Severe Disease in Patients With Common Variable Immunodeficiency.

PubMed

Ebbo, Mikael; Gérard, Laurence; Carpentier, Sabrina; Vély, Frédéric; Cypowyj, Sophie; Farnarier, Catherine; Vince, Nicolas; Malphettes, Marion; Fieschi, Claire; Oksenhendler, Eric; Schleinitz, Nicolas; Vivier, Eric

2016-04-01

Natural Killer (NK) cells have been shown to exert antiviral and antitumoural activities. Nevertheless most available data are derived from mouse models and functions of these cells in human remain unclear. To evaluate the impact of low circulating NK cell counts and to provide some clues to the role of NK cells in natural conditions, we studied a large cohort of patients with common variable immunodeficiency (CVID) included in a multicenter cohort of patients with primary hypogammaglobulinaemia. Patients were classified into three groups on the basis of their NK cell counts: severe and mild NK cell lymphopenia (<50 and 50-99×10(6)/L respectively), and normal NK cell counts (>100×10(6)/L). Clinical events were analyzed and compared between these three groups of patients. During study period, 457 CVID patients were included: 99 (21.7%) with severe NK cell lymphopenia, 118 (25.8%) with mild NK cell lymphopenia and 240 (52.5%) with normal NK cell counts. Non-infectious complications (57% vs. 36% and 35%), and, particularly, granulomatous complications (25.3% vs. 13.6% and 8.8%), were more frequent in patients with severe NK cell lymphopenia than in other groups. Invasive infections (68.7% vs. 60.2% and 48.8%), including bacteraemia (22.2% vs. 5.9% and 8.3%) and infectious pneumonia (63.6% vs. 59.3% and 44.2%), were also more frequent in this population. However, no difference was observed for viral infections and neoplasms. Low circulating NK cell counts are associated with more severe phenotypes of CVID, which may indicate a protective role of these immune cells against severe bacterial infections and other complications and non-redundant immune functions when the adaptive immune response is not optimal. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

The Human Natural Killer Cell Immune Synapse

NASA Astrophysics Data System (ADS)

Davis, Daniel M.; Chiu, Isaac; Fassett, Marlys; Cohen, George B.; Mandelboim, Ofer; Strominger, Jack L.

1999-12-01

Inhibitory killer Ig-like receptors (KIR) at the surface of natural killer (NK) cells induced clustering of HLA-C at the contacting surface of target cells. In this manner, inhibitory immune synapses were formed as human NK cells surveyed target cells. At target/NK cell synapses, HLA-C/KIR distributed into rings around central patches of intercellular adhesion molecule-1/lymphocyte function-associated antigen-1, the opposite orientation to mature murine T cell-activating synapses. This organization of protein was stable for at least 20 min. Cells could support multiple synapses simultaneously, and clusters of HLA-C moved as NK cells crawled over target cells. Clustering required a divalent metal cation, explaining how metal chelators inhibit KIR function. Surprisingly, however, formation of inhibitory synapses was unaffected by ATP depletion and the cytoskeletal inhibitors, colchicine and cytochalsins B and D. Clearly, supramolecular organization within plasma membranes is critical for NK cell immunosurveillance.

Natural killer cells as a therapeutic tool for infectious diseases – current status and future perspectives

PubMed Central

Schmidt, Stanislaw; Tramsen, Lars; Rais, Bushra; Ullrich, Evelyn; Lehrnbecher, Thomas

2018-01-01

Natural Killer (NK) cells are involved in the host immune response against infections due to viral, bacterial and fungal pathogens, all of which are a significant cause of morbidity and mortality in immunocompromised patients. Since the recovery of the immune system has a major impact on the outcome of an infectious complication, there is major interest in strengthening the host response in immunocompromised patients, either by using cytokines or growth factors or by adoptive cellular therapies transfusing immune cells such as granulocytes or pathogen-specific T-cells. To date, relatively little is known about the potential of adoptively transferring NK cells in immunocompromised patients with infectious complications, although the anti-cancer property of NK cells is already being investigated in the clinical setting. This review will focus on the antimicrobial properties of NK cells and the current standing and future perspectives of generating and using NK cells as immunotherapy in patients with infectious complications, an approach which is promising and might have an important clinical impact in the future. PMID:29755697

Role for early-differentiated natural killer cells in infectious mononucleosis

PubMed Central

Azzi, Tarik; Lünemann, Anna; Murer, Anita; Ueda, Seigo; Béziat, Vivien; Malmberg, Karl-Johan; Staubli, Georg; Gysin, Claudine; Berger, Christoph; Münz, Christian

2014-01-01

A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56dim NKG2A+ immunoglobulin-like receptor- NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus. PMID:25205117

Role for early-differentiated natural killer cells in infectious mononucleosis.

PubMed

Azzi, Tarik; Lünemann, Anna; Murer, Anita; Ueda, Seigo; Béziat, Vivien; Malmberg, Karl-Johan; Staubli, Georg; Gysin, Claudine; Berger, Christoph; Münz, Christian; Chijioke, Obinna; Nadal, David

2014-10-16

A growing body of evidence suggests that the human natural killer (NK)-cell compartment is phenotypically and functionally heterogeneous and is composed of several differentiation stages. Moreover, NK-cell subsets have been shown to exhibit adaptive immune features during herpes virus infection in experimental mice and to expand preferentially during viral infections in humans. However, both phenotype and role of NK cells during acute symptomatic Epstein-Barr virus (EBV) infection, termed infectious mononucleosis (IM), remain unclear. Here, we longitudinally assessed the kinetics, the differentiation, and the proliferation of subsets of NK cells in pediatric IM patients. Our results indicate that acute IM is characterized by the preferential proliferation of early-differentiated CD56(dim) NKG2A(+) immunoglobulin-like receptor(-) NK cells. Moreover, this NK-cell subset exhibits features of terminal differentiation and persists at higher frequency during at least the first 6 months after acute IM. Finally, we demonstrate that this NK-cell subset preferentially degranulates and proliferates on exposure to EBV-infected B cells expressing lytic antigens. Thus, early-differentiated NK cells might play a key role in the immune control of primary infection with this persistent tumor-associated virus. © 2014 by The American Society of Hematology.

Cytokines Induce Faster Membrane Diffusion of MHC Class I and the Ly49A Receptor in a Subpopulation of Natural Killer Cells

PubMed Central

Bagawath-Singh, Sunitha; Staaf, Elina; Stoppelenburg, Arie Jan; Spielmann, Thiemo; Kambayashi, Taku; Widengren, Jerker; Johansson, Sofia

2016-01-01

Cytokines have the potential to drastically augment immune cell activity. Apart from altering the expression of a multitude of proteins, cytokines also affect immune cell dynamics. However, how cytokines affect the molecular dynamics within the cell membrane of immune cells has not been addressed previously. Molecular movement is a vital component of all biological processes, and the rate of motion is, thus, an inherent determining factor for the pace of such processes. Natural killer (NK) cells are cytotoxic lymphocytes, which belong to the innate immune system. By fluorescence correlation spectroscopy, we investigated the influence of cytokine stimulation on the membrane density and molecular dynamics of the inhibitory receptor Ly49A and its ligand, the major histocompatibility complex class I allele H-2Dd, in freshly isolated murine NK cells. H-2Dd was densely expressed and diffused slowly in resting NK cells. Ly49A was expressed at a lower density and diffused faster. The diffusion rate in resting cells was not altered by disrupting the actin cytoskeleton. A short-term stimulation with interleukin-2 or interferon-α + β did not change the surface density of moving H-2Dd or Ly49A, despite a slight upregulation at the cellular level of H-2Dd by interferon-α + β, and of Ly49A by IL-2. However, the molecular diffusion rates of both H-2Dd and Ly49A increased significantly. A multivariate analysis revealed that the increased diffusion was especially marked in a subpopulation of NK cells, where the diffusion rate was increased around fourfold compared to resting NK cells. After IL-2 stimulation, this subpopulation of NK cells also displayed lower density of Ly49A and higher brightness per entity, indicating that Ly49A may homo-cluster to a larger extent in these cells. A faster diffusion of inhibitory receptors could enable a faster accumulation of these molecules at the immune synapse with a target cell, eventually leading to a more efficient NK cell response. It has previously been assumed that cytokines regulate immune cells primarily via alterations of protein expression levels or posttranslational modifications. These findings suggest that cytokines may also modulate immune cell efficiency by increasing the molecular dynamics early on in the response. PMID:26870035

Cetuximab-activated natural killer (NK) and dendritic cells (DC) collaborate to trigger tumor antigen-specific T cell immunity in head and neck cancer patients

PubMed Central

Srivastava, Raghvendra M.; Lee, Steve C.; Filho, Pedro A. Andrade; Lord, Christopher A.; Jie, Hyun-bae; Davidson, H. Carter; López-Albaitero, Andrés; Gibson, Sandra P.; Gooding, William E.; Ferrone, Soldano; Ferris, Robert L.

2013-01-01

Purpose Tumor antigen (TA)-specific monoclonal antibodies (mAb) block oncogenic signaling and induce Fcγ receptor (FcγR)-mediated cytotoxicity. However, the role of CD8+ cytotoxic T lymphocyte (CTL) and FcγR in initiating innate and adaptive immune responses in mAb-treated human cancer patients is still emerging. Experimental Design FcγRIIIa codon 158 polymorphism was correlated with survival in 107 cetuximab-treated head and neck cancer (HNC) patients. Flow cytometry was performed to quantify EGFR-specific T cells in cetuximab-treated HNC patients. The effect of cetuximab on NK cell, dendritic cell (DC), and T cell activation was measured using IFN-γ release assays and flow cytometry. Results FcγR IIIa polymorphism did not predict clinical outcome in cetuximab-treated HNC patients, however elevated circulating EGFR -specific CD8+ 853-861 T cells were found in cetuximab-treated HNC patients (p<0.005). Cetuximab promoted EGFR-specific cellular immunity through the interaction of EGFR+ tumor cells and FcγRIIIa on NK cells, but not on the polymorphism per se. Cetuximab-activated NK cells induced IFN-γ dependent expression of DC maturation markers, antigen presentation machinery (APM) components such as TAP-1/2, and Th1 chemokines through NKG2D/MICA binding. Cetuximab initiated adaptive immune responses via NK-cell induced DC maturation, which enhanced cross-presentation to CTL specific for EGFR as well as another TA, MAGE-3. Conclusion Cetuximab-activated NK cells promote DC maturation and CD8+ T cell priming, leading to TA spreading and Th1 cytokine release through ‘NK-DC cross-talk.’ FcγRIIIa polymorphism did not predict clinical response to cetuximab, but was necessary for NK-DC interaction and mAb induced cross-presentation. EGFR-specific T cells in cetuximab treated HNC patients may contribute to clinical response. PMID:23444227

CD137 Stimulation Enhances Cetuximab-Induced Natural Killer: Dendritic Cell Priming of Antitumor T-Cell Immunity in Patients with Head and Neck Cancer.

PubMed

Srivastava, Raghvendra M; Trivedi, Sumita; Concha-Benavente, Fernando; Gibson, Sandra P; Reeder, Carly; Ferrone, Soldano; Ferris, Robert L

2017-02-01

Cetuximab, an EGFR-specific antibody (mAb), modestly improves clinical outcome in patients with head and neck cancer (HNC). Cetuximab mediates natural killer (NK) cell:dendritic cell (DC) cross-talk by cross-linking FcγRIIIa, which is important for inducing antitumor cellular immunity. Cetuximab-activated NK cells upregulate the costimulatory receptor CD137 (4-1BB), which, when triggered by agonistic mAb urelumab, might enhance NK-cell functions, to promote T-cell-based immunity. CD137 expression on tumor-infiltrating lymphocytes was evaluated in a prospective cetuximab neoadjuvant trial, and CD137 stimulation was evaluated in a phase Ib trial, in combining agonistic urelumab with cetuximab. Flow cytometry and cytokine release assays using NK cells and DC were used in vitro, testing the addition of urelumab to cetuximab-activated NK, DC, and cross presentation to T cells. CD137 agonist mAb urelumab enhanced cetuximab-activated NK-cell survival, DC maturation, and tumor antigen cross-presentation. Urelumab boosted DC maturation markers, CD86 and HLA DR, and antigen-processing machinery (APM) components TAP1/2, leading to increased tumor antigen cross-presentation. In neoadjuvant cetuximab-treated patients with HNC, upregulation of CD137 by intratumoral, cetuximab-activated NK cells correlated with FcγRIIIa V/F polymorphism and predicted clinical response. Moreover, immune biomarker modulation was observed in an open label, phase Ib clinical trial, of patients with HNC treated with cetuximab plus urelumab. These results suggest a beneficial effect of combination immunotherapy using cetuximab and CD137 agonist in HNC. Clin Cancer Res; 23(3); 707-16. ©2016 AACR. ©2016 American Association for Cancer Research.

NK cell heparanase controls tumor invasion and immune surveillance

PubMed Central

Putz, Eva M.; Mayfosh, Alyce J.; Barkauskas, Deborah S.; Nakamura, Kyohei; Town, Liam; Goodall, Katharine J.; Yee, Dean Y.; Poon, Ivan K.H.; Baschuk, Nikola; Souza-Fonseca-Guimaraes, Fernando; Hulett, Mark D.; Smyth, Mark J.

2017-01-01

NK cells are highly efficient at preventing cancer metastasis but are infrequently found in the core of primary tumors. Here, have we demonstrated that freshly isolated mouse and human NK cells express low levels of the endo-β-D-glucuronidase heparanase that increase upon NK cell activation. Heparanase deficiency did not affect development, differentiation, or tissue localization of NK cells under steady-state conditions. However, mice lacking heparanase specifically in NK cells (Hpsefl/fl NKp46-iCre mice) were highly tumor prone when challenged with the carcinogen methylcholanthrene (MCA). Hpsefl/fl NKp46-iCre mice were also more susceptible to tumor growth than were their littermate controls when challenged with the established mouse lymphoma cell line RMA-S-RAE-1β, which overexpresses the NK cell group 2D (NKG2D) ligand RAE-1β, or when inoculated with metastatic melanoma, prostate carcinoma, or mammary carcinoma cell lines. NK cell invasion of primary tumors and recruitment to the site of metastasis were strictly dependent on the presence of heparanase. Cytokine and immune checkpoint blockade immunotherapy for metastases was compromised when NK cells lacked heparanase. Our data suggest that heparanase plays a critical role in NK cell invasion into tumors and thereby tumor progression and metastases. This should be considered when systemically treating cancer patients with heparanase inhibitors, since the potential adverse effect on NK cell infiltration might limit the antitumor activity of the inhibitors. PMID:28581441

Comparison of autogeneic and allogeneic natural killer cells immunotherapy on the clinical outcome of recurrent breast cancer

PubMed Central

Liang, Shuzhen; Xu, Kecheng; Niu, Lizhi; Wang, Xiaohua; Liang, Yingqing; Zhang, Mingjie; Chen, Jibing; Lin, Mao

2017-01-01

In the present study, we aimed to compare the clinical outcome of autogeneic and allogeneic natural killer (NK) cells immunotherapy for the treatment of recurrent breast cancer. Between July 2016 and February 2017, 36 patients who met the enrollment criteria were randomly assigned to two groups: autogeneic NK cells immunotherapy group (group I, n=18) and allogeneic NK cells immunotherapy group (group II, n=18). The clinical efficacy, quality of life, immune function, circulating tumor cell (CTC) level, and other related indicators were evaluated. We found that allogeneic NK cells immunotherapy has better clinical efficacy than autogeneic therapy. Moreover, allogeneic NK cells therapy improves the quality of life, reduces the number of CTCs, reduces carcinoembryonic antigen and cancer antigen 15-3 (CA15-3) expression, and significantly enhances immune function. To our knowledge, this is the first clinical trial to compare the clinical outcome of autogeneic and allogeneic NK cells immunotherapy for recurrent breast cancer. PMID:28894383

NK cells and poxvirus infection

PubMed Central

Burshtyn, Deborah N.

2013-01-01

In recent years, our understanding of the role of natural killer (NK) cells in the response to viral infection has grown rapidly. Not only do we realize viruses have many immune-evasion strategies to escape NK cell responses, but that stimulation of NK cell subsets during an antiviral response occurs through receptors seemingly geared directly at viral products and that NK cells can provide a memory response to viral pathogens. Tremendous knowledge has been gained in this area through the study of herpes viruses, but appreciation for the significance of NK cells in the response to other types of viral infections is growing. The function of NK cells in defense against poxviruses has emerged over several decades beginning with the early seminal studies showing the role of NK cells and the NK gene complex in susceptibility of mouse strains to ectromelia, a poxvirus pathogen of mice. More recently, greater understanding has emerged of the molecular details of the response. Given that human diseases caused by poxviruses can be as lethal as smallpox or as benign as Molluscum contagiosum, and that vaccinia virus, the prototypic member of the pox family, persists as a mainstay of vaccine design and has potential as an oncolytic virus for tumor therapy, further research in this area remains important. This review focuses on recent advances in understanding the role of NK cells in the immune response to poxviruses, the receptors involved in activation of NK cells during poxvirus infection, and the viral evasion strategies poxviruses employ to avoid the NK response. PMID:23372568

Bone Marrow-Derived Mesenchymal Stem Cells Attenuate Immune-Mediated Liver Injury and Compromise Virus Control During Acute Hepatitis B Virus Infection in Mice.

PubMed

Qu, Mengmeng; Yuan, Xu; Liu, Dan; Ma, Yuhong; Zhu, Jun; Cui, Jun; Yu, Mengxue; Li, Changyong; Guo, Deyin

2017-06-01

Mesenchymal stem cells (MSCs) have been used as therapeutic tools not only for their ability to differentiate toward different cells, but also for their unique immunomodulatory properties. However, it is still unknown how MSCs may affect immunity during hepatitis B virus (HBV) infection. This study was designed to explore the effect of bone marrow-derived MSCs (BM-MSCs) on hepatic natural killer (NK) cells in a mouse model of acute HBV infection. Mice were injected with 1 × 10 6 BM-MSCs, which stained with chloromethyl derivatives of fluorescein diacetate fluorescent probe, 24 h before hydrodynamic injection of viral DNA (pHBV1.3) through the tail vein. In vivo imaging system revealed that BM-MSCs were accumulated in the injured liver, and they attenuated immune-mediated liver injury during HBV infection, as shown by lower alanine aminotransferase levels, reduced proinflammatory cytokine production, and decreased inflammatory cell infiltration in the liver. Importantly, administration of BM-MSCs restrained the increased expression of natural-killer group 2, member D (NKG2D), an important receptor required for NK cell activation in the liver from HBV-infected mice. BM-MSCs also reduced NKG2D expression on NK cells and suppressed the cytotoxicity of NK cells in vitro. Furthermore, BM-MSC-derived transforming growth factor-β1 suppressed NKG2D expression on NK cells. As a consequence, BM-MSC treatment enhanced HBV gene expression and replication in vivo. These results demonstrate that adoptive transfer of BM-MSCs influences innate immunity and limits immune-mediated liver injury during acute HBV infection by suppressing NK cell activity. Meanwhile, the effect of BM-MSCs on prolonging virus clearance needs to be considered in the future.

The anti-tumor role of NK cells in vivo pre-activated and re-stimulated by interleukins in acute lymphoblastic leukemia

PubMed Central

Jin, Fengyan; Lin, Hai; Gao, Sujun; Hu, Zheng; Zuo, Song; Sun, Liguang; Jin, Chunhui; Li, Wei; Yang, Yanping

2016-01-01

Although natural killer cells (NK cells) were traditionally classified as members of the innate immune system, NK cells have recently been found also to be an important player in the adaptive immune systems. In this context, in vitro activation of NK cells by cytokines leads to generation of NK cells with memory-like properties characterized by increased interferon-γ (IFNγ) production. However, it remains to be defined whether these memory-like NK cells exist in vivo after cytokine activation. Furthermore, it is also unclear whether such memory-like NK cells induced in vivo by cytokines could have effective anti-leukemia response. To address these issues, we used an in vivo pre-activation and re-stimulation system that was able to produce NK cells with increased IFNγ secretion. It was found that after in vivo pre-activation and re-stimulation with interleukins (ILs), NK cells retained a state to produce increased amount of IFNγ. Of note, whereas this intrinsic capacity of enhanced IFNγ production after in vivo IL pre-activation and re-stimulation could be transferred to the next generation of NK cells and was associated with prolonged survival of the mice with acute lymphoid leukemia. Moreover, the anti-leukemia activity of these memory-like NK cells was associated with IFNγ production and up-regulation of NK cells activation receptor-NK Group 2 member D (NKG2D). Together, these findings argue strongly that in vivo IL pre-activation and re-stimulation is capable to induce memory-like NK cells as observed previously in vitro, which are effective against acute lymphoblastic leukemia, likely via NKG2D-dependent IFNγ production, in intact animals. PMID:27816971

The anti-tumor role of NK cells in vivo pre-activated and re-stimulated by interleukins in acute lymphoblastic leukemia.

PubMed

Jin, Fengyan; Lin, Hai; Gao, Sujun; Hu, Zheng; Zuo, Song; Sun, Liguang; Jin, Chunhui; Li, Wei; Yang, Yanping

2016-11-29

Although natural killer cells (NK cells) were traditionally classified as members of the innate immune system, NK cells have recently been found also to be an important player in the adaptive immune systems. In this context, in vitro activation of NK cells by cytokines leads to generation of NK cells with memory-like properties characterized by increased interferon-γ (IFNγ) production. However, it remains to be defined whether these memory-like NK cells exist in vivo after cytokine activation. Furthermore, it is also unclear whether such memory-like NK cells induced in vivo by cytokines could have effective anti-leukemia response. To address these issues, we used an in vivo pre-activation and re-stimulation system that was able to produce NK cells with increased IFNγ secretion. It was found that after in vivo pre-activation and re-stimulation with interleukins (ILs), NK cells retained a state to produce increased amount of IFNγ. Of note, whereas this intrinsic capacity of enhanced IFNγ production after in vivo IL pre-activation and re-stimulation could be transferred to the next generation of NK cells and was associated with prolonged survival of the mice with acute lymphoid leukemia. Moreover, the anti-leukemia activity of these memory-like NK cells was associated with IFNγ production and up-regulation of NK cells activation receptor-NK Group 2 member D (NKG2D). Together, these findings argue strongly that in vivo IL pre-activation and re-stimulation is capable to induce memory-like NK cells as observed previously in vitro, which are effective against acute lymphoblastic leukemia, likely via NKG2D-dependent IFNγ production, in intact animals.

Natural Killer Cell Recruitment to the Lung During Influenza A Virus Infection Is Dependent on CXCR3, CCR5, and Virus Exposure Dose

PubMed Central

Carlin, Lindsey E.; Hemann, Emily A.; Zacharias, Zeb R.; Heusel, Jonathan W.; Legge, Kevin L.

2018-01-01

Natural killer (NK) cells are vital components of the antiviral immune response, but their contributions in defense against influenza A virus (IAV) are not well understood. To better understand NK cell responses during IAV infections, we examined the magnitude, kinetics, and contribution of NK cells to immunity and protection during high- and low-dose IAV infections. Herein, we demonstrate an increased accumulation of NK cells in the lung in high-dose vs. low-dose infections. In part, this increase is due to the local proliferation of pulmonary NK cells. However, the majority of NK cell accumulation within the lungs and airways during an IAV infection is due to recruitment that is partially dependent upon CXCR3 and CCR5, respectively. Therefore, altogether, our results demonstrate that NK cells are actively recruited to the lungs and airways during IAV infection and that the magnitude of the recruitment may relate to the inflammatory environment found within the tissues during high- and low-dose IAV infections. PMID:29719539

Natural Killer Cell Function and Dysfunction in Hepatitis C Virus Infection

PubMed Central

Holder, Kayla A.; Russell, Rodney S.; Grant, Michael D.

2014-01-01

Viruses must continually adapt against dynamic innate and adaptive responses of the host immune system to establish chronic infection. Only a small minority (~20%) of those exposed to hepatitis C virus (HCV) spontaneously clear infection, leaving approximately 200 million people worldwide chronically infected with HCV. A number of recent research studies suggest that establishment and maintenance of chronic HCV infection involve natural killer (NK) cell dysfunction. This relationship is illustrated in vitro by disruption of typical NK cell responses including both cell-mediated cytotoxicity and cytokine production. Expression of a number of activating NK cell receptors in vivo is also affected in chronic HCV infection. Thus, direct in vivo and in vitro evidence of compromised NK function in chronic HCV infection in conjunction with significant epidemiological associations between the outcome of HCV infection and certain combinations of NK cell regulatory receptor and class I human histocompatibility linked antigen (HLA) genotypes indicate that NK cells are important in the immune response against HCV infection. In this review, we highlight evidence suggesting that selective impairment of NK cell activity is related to establishment of chronic HCV infection. PMID:25057504

The Impact of HLA Class I-Specific Killer Cell Immunoglobulin-Like Receptors on Antibody-Dependent Natural Killer Cell-Mediated Cytotoxicity and Organ Allograft Rejection

PubMed Central

Rajalingam, Raja

2016-01-01

Natural killer (NK) cells of the innate immune system are cytotoxic lymphocytes that play an important roles following transplantation of solid organs and hematopoietic stem cells. Recognition of self-human leukocyte antigen (HLA) class I molecules by inhibitory killer cell immunoglobulin-like receptors (KIRs) is involved in the calibration of NK cell effector capacities during the developmental stage, allowing the subsequent recognition and elimination of target cells with decreased expression of self-HLA class I (due to virus infection or tumor transformation) or HLA class I disparities (in the setting of allogeneic transplantation). NK cells expressing an inhibitory KIR-binding self-HLA can be activated when confronted with allografts lacking a ligand for the inhibitory receptor. Following the response of the adaptive immune system, NK cells can further destroy allograft endothelium by antibody-dependent cell-mediated cytotoxicity (ADCC), triggered through cross-linking of the CD16 Fc receptor by donor-specific antibodies bound to allograft. Upon recognizing allogeneic target cells, NK cells also secrete cytokines and chemokines that drive maturation of dendritic cells to promote cellular and humoral adaptive immune responses against the allograft. The cumulative activating and inhibitory signals generated by ligation of the receptors regulates mature NK cell killing of target cells and their production of cytokines and chemokines. This review summarizes the role of NK cells in allograft rejection and proposes mechanistic concepts that indicate a prominent role for KIR–HLA interactions in facilitating NK cells for Fc receptor-mediated ADCC effector function involved in antibody-mediated rejection of solid organ transplants. PMID:28066408

Actin retrograde flow controls natural killer cell response by regulating the conformation state of SHP-1.

PubMed

Matalon, Omri; Ben-Shmuel, Aviad; Kivelevitz, Jessica; Sabag, Batel; Fried, Sophia; Joseph, Noah; Noy, Elad; Biber, Guy; Barda-Saad, Mira

2018-03-01

Natural killer (NK) cells are a powerful weapon against viral infections and tumor growth. Although the actin-myosin (actomyosin) cytoskeleton is crucial for a variety of cellular processes, the role of mechanotransduction, the conversion of actomyosin mechanical forces into signaling cascades, was never explored in NK cells. Here, we demonstrate that actomyosin retrograde flow (ARF) controls the immune response of primary human NK cells through a novel interaction between β-actin and the SH2-domain-containing protein tyrosine phosphatase-1 (SHP-1), converting its conformation state, and thereby regulating NK cell cytotoxicity. Our results identify ARF as a master regulator of the NK cell immune response. Since actin dynamics occur in multiple cellular processes, this mechanism might also regulate the activity of SHP-1 in additional cellular systems. © 2018 The Authors.

IL-2 induces a WAVE2-dependent pathway for actin reorganization that enables WASp-independent human NK cell function.

PubMed

Orange, Jordan S; Roy-Ghanta, Sumita; Mace, Emily M; Maru, Saumya; Rak, Gregory D; Sanborn, Keri B; Fasth, Anders; Saltzman, Rushani; Paisley, Allison; Monaco-Shawver, Linda; Banerjee, Pinaki P; Pandey, Rahul

2011-04-01

Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency associated with an increased susceptibility to herpesvirus infection and hematologic malignancy as well as a deficiency of NK cell function. It is caused by defective WAS protein (WASp). WASp facilitates filamentous actin (F-actin) branching and is required for F-actin accumulation at the NK cell immunological synapse and NK cell cytotoxicity ex vivo. Importantly, the function of WASp-deficient NK cells can be restored in vitro after exposure to IL-2, but the mechanisms underlying this remain unknown. Using a WASp inhibitor as well as cells from patients with WAS, we have defined a direct effect of IL-2 signaling upon F-actin that is independent of WASp function. We found that IL-2 treatment of a patient with WAS enhanced the cytotoxicity of their NK cells and the F-actin content at the immunological synapses formed by their NK cells. IL-2 stimulation of NK cells in vitro activated the WASp homolog WAVE2, which was required for inducing WASp-independent NK cell function, but not for baseline activity. Thus, WAVE2 and WASp define parallel pathways to F-actin reorganization and function in human NK cells; although WAVE2 was not required for NK cell innate function, it was accessible through adaptive immunity via IL-2. These results demonstrate how overlapping cytoskeletal activities can utilize immunologically distinct pathways to achieve synonymous immune function.

IL-2 induces a WAVE2-dependent pathway for actin reorganization that enables WASp-independent human NK cell function

PubMed Central

Orange, Jordan S.; Roy-Ghanta, Sumita; Mace, Emily M.; Maru, Saumya; Rak, Gregory D.; Sanborn, Keri B.; Fasth, Anders; Saltzman, Rushani; Paisley, Allison; Monaco-Shawver, Linda; Banerjee, Pinaki P.; Pandey, Rahul

2011-01-01

Wiskott-Aldrich syndrome (WAS) is a primary immunodeficiency associated with an increased susceptibility to herpesvirus infection and hematologic malignancy as well as a deficiency of NK cell function. It is caused by defective WAS protein (WASp). WASp facilitates filamentous actin (F-actin) branching and is required for F-actin accumulation at the NK cell immunological synapse and NK cell cytotoxicity ex vivo. Importantly, the function of WASp-deficient NK cells can be restored in vitro after exposure to IL-2, but the mechanisms underlying this remain unknown. Using a WASp inhibitor as well as cells from patients with WAS, we have defined a direct effect of IL-2 signaling upon F-actin that is independent of WASp function. We found that IL-2 treatment of a patient with WAS enhanced the cytotoxicity of their NK cells and the F-actin content at the immunological synapses formed by their NK cells. IL-2 stimulation of NK cells in vitro activated the WASp homolog WAVE2, which was required for inducing WASp-independent NK cell function, but not for baseline activity. Thus, WAVE2 and WASp define parallel pathways to F-actin reorganization and function in human NK cells; although WAVE2 was not required for NK cell innate function, it was accessible through adaptive immunity via IL-2. These results demonstrate how overlapping cytoskeletal activities can utilize immunologically distinct pathways to achieve synonymous immune function. PMID:21383498

In vivo signaling through the neurokinin 1 receptor favors transgene expression by Langerhans cells and promotes the generation of Th1- and Tc1-biased immune responses.

PubMed

Mathers, Alicia R; Tckacheva, Olga A; Janelsins, Brian M; Shufesky, William J; Morelli, Adrian E; Larregina, Adriana T

2007-06-01

The proinflammatory capacities of the skin and the presence of high numbers of resident dendritic cells (DCs) constitute an ideal microenvironment for successful immunizations. Regardless of the ability of DCs to respond to local inflammatory signals in an immunostimulatory fashion, the immune functions of skin-resident DCs remain controversial, and epidermal Langerhans cells (LCs) have been referred to recently as anti-inflammatory/protolerogenic APCs. Substance P (SP), released by skin nerve fibers, is a potent proinflammatory neuropeptide that favors development of skin-associated cellular immunity. SP exerts its proinflammatory functions by binding with high affinity to the neurokinin 1 receptor (NK1R). In this study, we tested whether signaling skin cells via the NK1R promotes humoral and cellular immunity during skin genetic immunizations. We used the gene gun to deliver transgenic (tg) Ag to the skin of C57BL/6 mice and the selective NK1R agonist [Sar(9)Met (O(2)) (11)]-SP as a potential proinflammatory Th1-biasing adjuvant. Our strategy expressed tg Ag exclusively in the epidermis and induced a preferential migration of activated LCs to skin-draining lymph nodes. Local administration of the NK1R agonist during skin genetic immunizations increased significantly the expression of tg Ag by a mechanism involving the translocation of NF-kappaB into the nuclei of cutaneous DCs homing to skin-draining lymph nodes. Importantly, our immunization approach resulted in Th1 and T cytotoxic (CTL)-1 bias of effector T cells that supported cellular and Ab-mediated immune responses. We demonstrate that signaling skin cells via the NK1R provides the adjuvant effect which favors the immunostimulatory functions of LCs.

Human liver-resident CD56(bright)/CD16(neg) NK cells are retained within hepatic sinusoids via the engagement of CCR5 and CXCR6 pathways.

PubMed

Hudspeth, Kelly; Donadon, Matteo; Cimino, Matteo; Pontarini, Elena; Tentorio, Paolo; Preti, Max; Hong, Michelle; Bertoletti, Antonio; Bicciato, Silvio; Invernizzi, Pietro; Lugli, Enrico; Torzilli, Guido; Gershwin, M Eric; Mavilio, Domenico

2016-01-01

The liver-specific natural killer (NK) cell population is critical for local innate immune responses, but the mechanisms that lead to their selective homing and the definition of their functionally relevance remain enigmatic. We took advantage of the availability of healthy human liver to rigorously define the mechanisms regulating the homing of NK cells to liver and the repertoire of receptors that distinguish liver-resident NK (lr-NK) cells from circulating counterparts. Nearly 50% of the entire liver NK cell population is composed of functionally relevant CD56(bright) lr-NK cells that localize within hepatic sinusoids. CD56(bright) lr-NK cells express CD69, CCR5 and CXCR6 and this unique repertoire of chemokine receptors is functionally critical as it determines selective migration in response to the chemotactic stimuli exerted by CCL3, CCL5 and CXCL16. Here, we also show that hepatic sinusoids express CCL3(pos) Kupffer cells, CXCL16(pos) endothelial cells and CCL5(pos) T and NK lymphocytes. The selective presence of these chemokines in sinusoidal spaces creates a unique tissue niche for lr-CD56(bright) NK cells that constitutively express CCR5 and CXCR6. CD56(bright) lr-NK cells co-exist with CD56(dim) conventional NK (c-NK) cells that are, interestingly, transcriptionally and phenotypically similar to their peripheral circulating counterparts. Indeed, CD56(dim) c-NK cells lack expression of CD69, CCR5, and CXCR6 but express selectins, integrins and CX3CR1. Our findings disclosing the phenotypic and functional differences between lr-Nk cells and c-NK cells are critical to distinguish liver-specific innate immune responses. Hence, any therapeutic attempts at modifying the large population of CD56(bright) lr-NK cells will require modification of hepatic CCR5 and CXCR6. Copyright © 2015 Elsevier Ltd. All rights reserved.

Human liver-resident CD56bright/CD16neg NK cells are retained within hepatic sinusoids via the engagement of CCR5 and CXCR6 pathways

PubMed Central

Hudspeth, Kelly; Donadon, Matteo; Cimino, Matteo; Pontarini, Elena; Tentorio, Paolo; Preti, Max; Hong, Michelle; Bertoletti, Antonio; Bicciato, Silvio; Invernizzi, Pietro; Lugli, Enrico; Torzilli, Guido; Gershwin, M. Eric; Mavilio, Domenico

2015-01-01

Rationale The liver-specific natural killer (NK) cell population is critical for local innate immune responses, but the mechanisms that lead to their selective homing and the definition of their functionally relevance remain enigmatic. Objectives We took advantage of the availability of healthy human liver to rigorously define the mechanisms regulating the homing of NK cells to liver and the repertoire of receptors that distinguish liver-resident NK (lr-NK) cells from circulating counterparts. Findings Nearly 50% of the entire liver NK cell population is composed of functionally relevant CD56bright lr-NK cells that localize within hepatic sinusoids. Further, CD56bright lr-NK cells express CD69, CCR5 and CXCR6 and this unique repertoire of chemokine receptors is functionally critical as it determines selective migration in response to the chemotactic stimuli exerted by CCL3, CCL5 and CXCL16. In addition, hepatic sinusoids express CCL3pos Kupffer cells, CXCL16pos endothelial cells and CCL5pos T and NK lymphocytes. The selective presence of these chemokines in sinusoidal spaces creates a tissue niche for lr-CD56bright NK cells that constitutively express CCR5 and CXCR6. CD56bright lr-NK cells co-exist with CD56dim conventional NK (c-NK) cells that are, interestingly, transcriptionally and phenotypically similar to their peripheral circulating counterparts. Indeed, CD56dim c-NK cells lack expression of CD69, CCR5, and CXCR6 but express selectins, integrins and CX3CR1. Conclusion Our findings disclosing the phenotypic and functional differences between lr-Nk cells and c-NK cells are critical to distinguish liver-specific innate immune responses. Hence, any therapeutic attempts at modifying the large population of CD56bright lr-NK cells will require modification of hepatic CCR5 and CXCR6. PMID:26330348

Immunological modes of pregnancy loss: inflammation, immune effectors, and stress.

PubMed

Kwak-Kim, Joanne; Bao, Shihua; Lee, Sung Ki; Kim, Joon Woo; Gilman-Sachs, Alice

2014-08-01

Inflammatory immune response plays a key role in reproductive failures such as multiple implantation failures (MIF), early pregnancy loss, and recurrent pregnancy losses (RPL). Cellular immune responses particularly mediated by natural killer (NK), and T cells are often dysregulated in these conditions. Excessive or inappropriate recruitment of peripheral blood NK cells to the uterus may lead to cytotoxic environment in utero, in which proliferation and differentiation of trophoblast is hampered. In addition, inadequate angiogenesis by uterine NK cells often leads to abnormal vascular development and blood flow patterns, which, in turn, leads to increased oxidative stress or ischemic changes in the invading trophoblast. T-cell abnormalities with increased Th1 and Th17 immunity, and decreased Th2 and T regulatory immune responses may play important roles in RPL and MIF. A possible role of stress in inflammatory immune response is also reviewed. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Single-cell transcriptome analysis of fish immune cells provides insight into the evolution of vertebrate immune cell types.

PubMed

Carmona, Santiago J; Teichmann, Sarah A; Ferreira, Lauren; Macaulay, Iain C; Stubbington, Michael J T; Cvejic, Ana; Gfeller, David

2017-03-01

The immune system of vertebrate species consists of many different cell types that have distinct functional roles and are subject to different evolutionary pressures. Here, we first analyzed conservation of genes specific for all major immune cell types in human and mouse. Our results revealed higher gene turnover and faster evolution of trans -membrane proteins in NK cells compared with other immune cell types, and especially T cells, but similar conservation of nuclear and cytoplasmic protein coding genes. To validate these findings in a distant vertebrate species, we used single-cell RNA sequencing of lck:GFP cells in zebrafish and obtained the first transcriptome of specific immune cell types in a nonmammalian species. Unsupervised clustering and single-cell TCR locus reconstruction identified three cell populations, T cells, a novel type of NK-like cells, and a smaller population of myeloid-like cells. Differential expression analysis uncovered new immune-cell-specific genes, including novel immunoglobulin-like receptors, and neofunctionalization of recently duplicated paralogs. Evolutionary analyses confirmed the higher gene turnover of trans -membrane proteins in NK cells compared with T cells in fish species, suggesting that this is a general property of immune cell types across all vertebrates. © 2017 Carmona et al.; Published by Cold Spring Harbor Laboratory Press.

Effects of a cloned cell line with NK activity on bone marrow transplants, tumour development and metastasis in vivo

NASA Astrophysics Data System (ADS)

Warner, John F.; Dennert, Gunther

1982-11-01

Natural killer (NK) cells cloned in vitro have been transferred into NK-deficient hosts. These cells have been shown to have a role in the rejection of allogeneic bone marrow grafts, resistance to both radiation-induced thymic leukaemia and challenge with melanoma tumour cells. It appears that NK cells have an important role in immune surveillance.

Natural killer cell subsets in cerebrospinal fluid of patients with multiple sclerosis

PubMed Central

Rodríguez-Martín, E; Picón, C; Costa-Frossard, L; Alenda, R; Sainz de la Maza, S; Roldán, E; Espiño, M; Villar, L M; Álvarez-Cermeño, J C

2015-01-01

Changes in blood natural killer (NK) cells, important players of the immune innate system, have been described in multiple sclerosis (MS). We studied percentages and total cell counts of different effector and regulatory NK cells in cerebrospinal fluid (CSF) of MS patients and other neurological diseases to gain clearer knowledge of the role of these cells in neuroinflammation. NK cell subsets were assessed by flow cytometry in CSF of 85 consecutive MS patients (33 with active disease and 52 with stable MS), 16 with other inflammatory diseases of the central nervous system (IND) and 17 with non-inflammatory neurological diseases (NIND). MS patients showed a decrease in percentages of different CSF NK subpopulations compared to the NIND group. However, absolute cell counts showed a significant increase of all NK subsets in MS and IND patients, revealing that the decrease in percentages does not reflect a real reduction of these immune cells. Remarkably, MS patients showed a significant increase of regulatory/effector (CD56bright/CD56dim) NK ratio compared to IND and NIND groups. In addition, MS activity associated with an expansion of NK T cells. These data show that NK cell subsets do not increase uniformly in all inflammatory neurological disease and suggest strongly that regulatory CD56bright and NK T cells may arise in CSF of MS patients as an attempt to counteract the CNS immune activation characteristic of the disease. PMID:25565222

Generation of natural killer cells from hematopoietic stem cells in vitro for immunotherapy

PubMed Central

Luevano, Martha; Madrigal, Alejandro; Saudemont, Aurore

2012-01-01

Natural killer (NK) cells are part of the innate immune system and are an alluring option for immunotherapy due to their ability to kill infected cells or cancer cells without prior sensitization. Throughout the past 20 years, different groups have been able to reproduce NK cell development in vitro, and NK cell ontogeny studies have provided the basis for the establishment of protocols to produce NK cells in vitro for immunotherapy. Here, we briefly discuss NK cell development and NK cell immunotherapy approaches. We review the factors needed for NK cell differentiation in vitro, which stem cell sources have been used, published protocols, challenges and future directions for Good Manufacturing Practice protocols. PMID:22705914

Generation of cellular immune memory and B-cell immunity is impaired by natural killer cells.

PubMed

Rydyznski, Carolyn; Daniels, Keith A; Karmele, Erik P; Brooks, Taylor R; Mahl, Sarah E; Moran, Michael T; Li, Caimei; Sutiwisesak, Rujapak; Welsh, Raymond M; Waggoner, Stephen N

2015-02-27

The goal of most vaccines is the induction of long-lived memory T and B cells capable of protecting the host from infection by cytotoxic mechanisms, cytokines and high-affinity antibodies. However, efforts to develop vaccines against major human pathogens such as HIV and HCV have not been successful, thereby highlighting the need for novel approaches to circumvent immunoregulatory mechanisms that limit the induction of protective immunity. Here, we show that mouse natural killer (NK) cells inhibit generation of long-lived virus-specific memory T- and B cells as well as virus-specific antibody production after acute infection. Mechanistically, NK cells suppressed CD4 T cells and follicular helper T cells (T(FH)) in a perforin-dependent manner during the first few days of infection, resulting in a weaker germinal centre (GC) response and diminished immune memory. We anticipate that innovative strategies to relieve NK cell-mediated suppression of immunity should facilitate development of efficacious new vaccines targeting difficult-to-prevent infections.

Single-cell transcriptome analysis of fish immune cells provides insight into the evolution of vertebrate immune cell types

PubMed Central

Ferreira, Lauren; Macaulay, Iain C.; Stubbington, Michael J.T.

2017-01-01

The immune system of vertebrate species consists of many different cell types that have distinct functional roles and are subject to different evolutionary pressures. Here, we first analyzed conservation of genes specific for all major immune cell types in human and mouse. Our results revealed higher gene turnover and faster evolution of trans-membrane proteins in NK cells compared with other immune cell types, and especially T cells, but similar conservation of nuclear and cytoplasmic protein coding genes. To validate these findings in a distant vertebrate species, we used single-cell RNA sequencing of lck:GFP cells in zebrafish and obtained the first transcriptome of specific immune cell types in a nonmammalian species. Unsupervised clustering and single-cell TCR locus reconstruction identified three cell populations, T cells, a novel type of NK-like cells, and a smaller population of myeloid-like cells. Differential expression analysis uncovered new immune-cell–specific genes, including novel immunoglobulin-like receptors, and neofunctionalization of recently duplicated paralogs. Evolutionary analyses confirmed the higher gene turnover of trans-membrane proteins in NK cells compared with T cells in fish species, suggesting that this is a general property of immune cell types across all vertebrates. PMID:28087841

Toxoplasma gondii-infected natural killer cells display a hypermotility phenotype in vivo.

PubMed

Ueno, Norikiyo; Lodoen, Melissa B; Hickey, Graeme L; Robey, Ellen A; Coombes, Janine L

2015-01-01

Toxoplasma gondii is a highly prevalent intracellular protozoan parasite that causes severe disease in congenitally infected or immunocompromised hosts. T. gondii is capable of invading immune cells and it has been suggested that the parasite harnesses the migratory pathways of these cells to spread through the body. Although in vitro evidence suggests that the parasite further enhances its spread by inducing a hypermotility phenotype in parasitized immune cells, in vivo evidence for this phenomenon is scarce. Here we use a physiologically relevant oral model of T. gondii infection, in conjunction with two-photon laser scanning microscopy, to address this issue. We found that a small proportion of natural killer (NK) cells in mesenteric lymph nodes contained parasites. Compared with uninfected 'bystander' NK cells, these infected NK cells showed faster, more directed and more persistent migratory behavior. Consistent with this, infected NK cells showed impaired spreading and clustering of the integrin, LFA-1, when exposed to plated ligands. Our results provide the first evidence for a hypermigratory phenotype in T. gondii-infected NK cells in vivo, providing an anatomical context for understanding how the parasite manipulates immune cell motility to spread through the host.

Licensed human natural killer cells aid dendritic cell maturation via TNFSF14/LIGHT

PubMed Central

Holmes, Tim D.; Wilson, Erica B.; Black, Emma V. I.; Benest, Andrew V.; Vaz, Candida; Tan, Betty; Tanavde, Vivek M.; Cook, Graham P.

2014-01-01

Interactions between natural killer (NK) cells and dendritic cells (DCs) aid DC maturation and promote T-cell responses. Here, we have analyzed the response of human NK cells to tumor cells, and we identify a pathway by which NK–DC interactions occur. Gene expression profiling of tumor-responsive NK cells identified the very rapid induction of TNF superfamily member 14 [TNFSF14; also known as homologous to lymphotoxins, exhibits inducible expression, and competes with HSV glycoprotein D for HVEM, a receptor expressed by T lymphocytes (LIGHT)], a cytokine implicated in the enhancement of antitumor responses. TNFSF14 protein expression was induced by three primary mechanisms of NK cell activation, namely, via the engagement of CD16, by the synergistic activity of multiple target cell-sensing NK-cell activation receptors, and by the cytokines IL-2 and IL-15. For antitumor responses, TNFSF14 was preferentially produced by the licensed NK-cell population, defined by the expression of inhibitory receptors specific for self-MHC class I molecules. In contrast, IL-2 and IL-15 treatment induced TNFSF14 production by both licensed and unlicensed NK cells, reflecting the ability of proinflammatory conditions to override the licensing mechanism. Importantly, both tumor- and cytokine-activated NK cells induced DC maturation in a TNFSF14-dependent manner. The coupling of TNFSF14 production to tumor-sensing NK-cell activation receptors links the tumor immune surveillance function of NK cells to DC maturation and adaptive immunity. Furthermore, regulation by NK cell licensing helps to safeguard against TNFSF14 production in response to healthy tissues. PMID:25512551

Two photon microscopy intravital study of DC-mediated anti-tumor response of NK cells

NASA Astrophysics Data System (ADS)

Caccia, Michele; Gorletta, Tatiana; Sironi, Laura; Zanoni, Ivan; Salvetti, Cristina; Collini, Maddalena; Granucci, Francesca; Chirico, Giuseppe

2010-02-01

Recent studies have demonstrated that dendritic cells (DCs) play a crucial role in the activation of Natural Killer cells (NKs) that are responsible for anti-tumor innate immune responses. The focus of this report is on the role of pathogen associated molecular pattern (PAMP) activated-DCs in inducing NK cell-mediated anti-tumor responses. Mice transplanted sub-cute (s.c.) with AK7 cells, a mesothelioma cell line sensitive to NK cell responses, are injected with fluorescent NK cells and DC activation is then induced by s.c. injection of Lipopolysaccharide (LPS). Using 4 dimensional tracking we follow the kinetic behavior of NK cells at the Draining Lymph-Node (DLN). As control, noninflammatory conditions are also evaluated. Our data suggest that NK cells are recruited to the DLN where they can interact with activated-DCs with a peculiar kinetic behavior: short lived interactions interleaved by rarer longer ones. We also found that the changes in the NK dynamic behavior in inflammatory conditions clearly affect relevant motility parameters such as the instantaneous and average velocity and the effective diffusion coefficient. This observation suggests that NK cells and activated-DCs might efficiently interact in the DLN, where cells could be activated. Therefore the interaction between activated-DCs and NK cells in DLN is not only a reality but it may be also crucial for the start of the immune response of the NKs.

Natural killer cells facilitate PRAME-specific T-cell reactivity against neuroblastoma

PubMed Central

Spel, Lotte; Boelens, Jaap-Jan; van der Steen, Dirk M.; Blokland, Nina J.G.; van Noesel, Max M.; Molenaar, Jan J.; Heemskerk, Mirjam H.M.

2015-01-01

Neuroblastoma is the most common solid tumor in children with an estimated 5-year progression free survival of 20–40% in stage 4 disease. Neuroblastoma actively avoids recognition by natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). Although immunotherapy has gained traction for neuroblastoma treatment, these immune escape mechanisms restrain clinical results. Therefore, we aimed to improve neuroblastoma immunogenicity to further the development of antigen-specific immunotherapy against neuroblastoma. We found that neuroblastoma cells significantly increase surface expression of MHC I upon exposure to active NK cells which thereby readily sensitize neuroblastoma cells for recognition by CTLs. We show that oncoprotein PRAME serves as an immunodominant antigen for neuroblastoma as NK-modulated neuroblastoma cells are recognized by PRAMESLLQHLIGL/A2-specific CTL clones. Furthermore, NK cells induce MHC I upregulation in neuroblastoma through contact-dependent secretion of IFNγ. Our results demonstrate remarkable plasticity in the peptide/MHC I surface expression of neuroblastoma cells, which is reversed when neuroblastoma cells experience innate immune attack by sensitized NK cells. These findings support the exploration of NK cells as adjuvant therapy to enforce neuroblastoma-specific CTL responses. PMID:26452036

Activating receptors promote NK cell expansion for maintenance, IL-10 production, and CD8 T cell regulation during viral infection.

PubMed

Lee, Seung-Hwan; Kim, Kwang-Sin; Fodil-Cornu, Nassima; Vidal, Silvia M; Biron, Christine A

2009-09-28

Natural killer (NK) cells have the potential to deliver both direct antimicrobial effects and regulate adaptive immune responses, but NK cell yields have been reported to vary greatly during different viral infections. Activating receptors, including the Ly49H molecule recognizing mouse cytomegalovirus (MCMV), can stimulate NK cell expansion. To define Ly49H's role in supporting NK cell proliferation and maintenance under conditions of uncontrolled viral infection, experiments were performed in Ly49h(-/-), perforin 1 (Prf1)(-/-), and wild-type (wt) B6 mice. NK cell numbers were similar in uninfected mice, but relative to responses in MCMV-infected wt mice, NK cell yields declined in the absence of Ly49h and increased in the absence of Prf1, with high rates of proliferation and Ly49H expression on nearly all cells. The expansion was abolished in mice deficient for both Ly49h and Prf1 (Ly49h(-/-)Prf1(-/-)), and negative consequences for survival were revealed. The Ly49H-dependent protection mechanism delivered in the absence of Prf1 was a result of interleukin 10 production, by the sustained NK cells, to regulate the magnitude of CD8 T cell responses. Thus, the studies demonstrate a previously unappreciated critical role for activating receptors in keeping NK cells present during viral infection to regulate adaptive immune responses.

Immune cell activation and cytokine release after stimulation of whole blood with pneumococcal C-polysaccharide and capsular polysaccharides.

PubMed

Sundberg-Kövamees, Marianne; Grunewald, Johan; Wahlström, Jan

2016-11-01

Streptococcus pneumonia is a major cause of morbidity and mortality in children and adults worldwide. Lack of fully effective pneumococcal vaccines is a problem. Streptococcus pneumoniae exposes on its surface C-polysaccharide (cell wall polysaccharide, CWPS) and serospecific capsular polysaccharides, used in pneumococcal vaccines. We investigated the effect of CWPS and individual capsular polysaccharides, with regard to activation of subsets of immune cells of healthy controls. Three different capsular polysaccharides, CWPS and LPS were used for in vitro stimulation of whole blood. Cell activation (CD69 expression) was assessed in CD4+ and CD4- T cells, NK-like T cells, NK cells and monocytes by flow cytometry. Cytokine levels in supernatants were quantified by Cytometric Bead Array (CBA). CWPS and the capsules activated immune cell subsets, but to different degrees. NK cells and NK-like T cells showed the strongest activation, followed by monocytes. Among the three capsules, capsule type 23 induced the strongest activation and cytokine release, followed by type 9 and type 3. This study increases the understanding of how the human immune system reacts to pneumococcal vaccine components. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

NK Cells and Their Role in Invasive Mold Infection.

PubMed

Schmidt, Stanislaw; Condorelli, Annalisa; Koltze, Antonia; Lehrnbecher, Thomas

2017-05-19

There is growing evidence that Natural Killer (NK) cells exhibit in vitro activity against both Aspergillus and non- Aspergillus molds. Cytotoxic molecules such as NK cell-derived perforin seem to play an important role in the antifungal activity. In addition, NK cells release a number of cytokines upon stimulation by fungi, which modulate both innate and adaptive host immune responses. Whereas the in vitro data of the antifungal activity of NK cells are supported by animal studies, clinical data are scarce to date.

Large-Scale Culture and Genetic Modification of Human Natural Killer Cells for Cellular Therapy.

PubMed

Lapteva, Natalia; Parihar, Robin; Rollins, Lisa A; Gee, Adrian P; Rooney, Cliona M

2016-01-01

Recent advances in methods for the ex vivo expansion of human natural killer (NK) cells have facilitated the use of these powerful immune cells in clinical protocols. Further, the ability to genetically modify primary human NK cells following rapid expansion allows targeting and enhancement of their immune function. We have successfully adapted an expansion method for primary NK cells from peripheral blood mononuclear cells or from apheresis products in gas permeable rapid expansion devices (G-Rexes). Here, we describe an optimized protocol for rapid and robust NK cell expansion as well as a method for highly efficient retroviral transduction of these ex vivo expanded cells. These methodologies are good manufacturing practice (GMP) compliant and could be used for clinical-grade product manufacturing.

Chimeric antigen receptor-engineered natural killer and natural killer T cells for cancer immunotherapy.

PubMed

Bollino, Dominique; Webb, Tonya J

2017-09-01

Natural killer (NK) cells of the innate immune system and natural killer T (NKT) cells, which have roles in both the innate and adaptive responses, are unique lymphocyte subsets that have similarities in their functions and phenotypes. Both cell types can rapidly respond to the presence of tumor cells and participate in immune surveillance and antitumor immune responses. This has incited interest in the development of novel cancer therapeutics based on NK and NKT cell manipulation. Chimeric antigen receptors (CARs), generated through the fusion of an antigen-binding region of a monoclonal antibody or other ligand to intracellular signaling domains, can enhance lymphocyte targeting and activation toward diverse malignancies. Most of the CAR studies have focused on their expression in T cells; however, the functional heterogeneity of CAR T cells limits their therapeutic potential and is associated with toxicity. CAR-modified NK and NKT cells are becoming more prevalent because they provide a method to direct these cells more specifically to target cancer cells, with less risk of adverse effects. This review will outline current NK and NKT cell CAR constructs and how they compare to conventional CAR T cells, and discuss future modifications that can be explored to advance adoptive cell transfer of NK and NKT cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Tyrosine Kinase Btk Is Required for NK Cell Activation

PubMed Central

Bao, Yan; Zheng, Jian; Han, Chaofeng; Jin, Jing; Han, Huanxing; Liu, Yinping; Lau, Yu-Lung; Tu, Wenwei; Cao, Xuetao

2012-01-01

Bruton tyrosine kinase (Btk) is not only critical for B cell development and differentiation but is also involved in the regulation of Toll-like receptor-triggered innate response of macrophages. However, whether Btk is involved in the regulation of natural killer (NK) cell innate function remains unknown. Here, we show that Btk expression is up-regulated during maturation and activation of mouse NK cells. Murine Btk−/− NK cells have decreased innate immune responses to the TLR3 ligand, with reduced expressions of IFN-γ, perforin, and granzyme-B and decreased cytotoxic activity. Furthermore, Btk is found to promote TLR3-triggered NK cell activation mainly by activating the NF-κB pathway. Poly(I:C)-induced NK cell-mediated acute hepatitis was observed to be attenuated in Btk−/− mice or the mice with in vivo administration of the Btk inhibitor. Correspondingly, liver damage was aggravated in Btk−/− mice after the adoptive transfer of Btk+/+ NK cells, further indicating that Btk-mediated NK cell activation contributes to TLR3-triggered acute liver injury. Importantly, reduced TLR3-triggered activation of human NK cells was observed in Btk-deficient patients with X-linked agammaglobulinemia, as evidenced by the reduced IFN-γ, CD69, and CD107a expression and cytotoxic activity. These results indicate that Btk is required for activation of NK cells, thus providing insight into the physiological significance of Btk in the regulation of immune cell functions and innate inflammatory response. PMID:22589540

Tyrosine kinase Btk is required for NK cell activation.

PubMed

Bao, Yan; Zheng, Jian; Han, Chaofeng; Jin, Jing; Han, Huanxing; Liu, Yinping; Lau, Yu-Lung; Tu, Wenwei; Cao, Xuetao

2012-07-06

Bruton tyrosine kinase (Btk) is not only critical for B cell development and differentiation but is also involved in the regulation of Toll-like receptor-triggered innate response of macrophages. However, whether Btk is involved in the regulation of natural killer (NK) cell innate function remains unknown. Here, we show that Btk expression is up-regulated during maturation and activation of mouse NK cells. Murine Btk(-/-) NK cells have decreased innate immune responses to the TLR3 ligand, with reduced expressions of IFN-γ, perforin, and granzyme-B and decreased cytotoxic activity. Furthermore, Btk is found to promote TLR3-triggered NK cell activation mainly by activating the NF-κB pathway. Poly(I:C)-induced NK cell-mediated acute hepatitis was observed to be attenuated in Btk(-/-) mice or the mice with in vivo administration of the Btk inhibitor. Correspondingly, liver damage was aggravated in Btk(-/-) mice after the adoptive transfer of Btk(+/+) NK cells, further indicating that Btk-mediated NK cell activation contributes to TLR3-triggered acute liver injury. Importantly, reduced TLR3-triggered activation of human NK cells was observed in Btk-deficient patients with X-linked agammaglobulinemia, as evidenced by the reduced IFN-γ, CD69, and CD107a expression and cytotoxic activity. These results indicate that Btk is required for activation of NK cells, thus providing insight into the physiological significance of Btk in the regulation of immune cell functions and innate inflammatory response.

Altered Gene Expression and Function of Peripheral Blood Natural Killer Cells in Children with Autism

PubMed Central

Enstrom, A M; Lit, L; Onore, C E; Gregg, J P; Hansen, R; Pessah, I N; Hertz-Picciotto, I; Van de Water, J A; Sharp, F R; Ashwood, P

2009-01-01

Immune related abnormalities have repeatedly been reported in autism spectrum disorders (ASD), including evidence of immune dysregulation and autoimmune phenomena. NK cells may play an important role in neurodevelopmental disorders such as ASD. Here we performed a gene expression screen and cellular functional analysis on peripheral blood obtained from 52 children with ASD and 27 typically developing control children enrolled in the case-control CHARGE study. RNA expression of NK cell receptors and effector molecules were significantly upregulated in ASD. Flow cytometric analysis of NK cells demonstrated increased production of perforin, granzyme B, and interferon gamma (IFNγ) under resting conditions in children with ASD (p<0.01). Following NK cell stimulation in the presence of K562 target cells, the cytotoxicity of NK cells was significantly reduced in ASD compared with controls (p<0.02). Furthermore, under similar stimulation conditions the presence of perforin, granzyme B, and IFNγ in NK cells from ASD children was significantly lower compared with controls (p<0.001). These findings suggest possible dysfunction of NK cells in children with ASD. Abnormalities in NK cells may represent a susceptibility factor in ASD and may predispose to the development of autoimmunity and/or adverse neuroimmune interactions during critical periods of development. PMID:18762240

Modulation of innate and adaptive cellular immunity relevant to HIV-1 vaccine design by seminal plasma.

PubMed

Selva, Kevin J; Kent, Stephen J; Parsons, Matthew S

2017-01-28

Mucosal exposure to HIV-1 infection generally occurs in the presence of semen. Immunomodulation by seminal plasma is well described in the reproductive biology literature. Little is known, however, about the impact of seminal plasma on innate and adaptive anti-HIV-1 cellular immunity. The study investigated the effects of seminal plasma on immune responses considered important for prophylactic HIV-1 vaccine development, namely innate and adaptive cellular immunity mediated by natural killer (NK) cells and T cells, respectively. The ability of seminal plasma to modulate direct, antibody-dependent and cytokine-stimulated NK cell activation was assessed utilizing intracellular cytokine staining. Direct and antibody-dependent cellular cytotoxicity was assessed using lactate dehydrogenase release assays. The effects of seminal plasma on T-cell activation upon stimulation with staphylococcus enterotoxin B or HIV-1 Gag peptides were assessed by intracellular cytokine staining. The impact of seminal plasma on redirected cytolysis mediated by T cells was measured using lactate dehydrogenase release assays. Both direct and antibody-dependent NK cell activation were dramatically impaired by the presence of either HIV-1-uninfected or HIV-1-infected seminal plasma in a dose-dependent manner. Additionally, seminal plasma suppressed both direct and antibody-dependent NK cell-mediated cytolysis, including anti-HIV-1 antibody-dependent cytolysis of gp120-pulsed CEM.NKr-CCR5 cells. Finally, seminal plasma attenuated both HIV-1 Gag-specific and staphylococcus enterotoxin B-induced CTL activation. Semen contains potent immunosuppressors of both NK cell and CD8 T-cell-mediated anti-HIV-1 immune responses. This could impede attempts to provide vaccine-induced immunity to HIV-1.

Activated natural killer cell-mediated immunity is required for the inhibition of tumor metastasis by dendritic cell vaccination.

PubMed

Kim, Aeyung; Noh, Young-Woock; Kim, Kwang Dong; Jang, Yong-Suk; Choe, Yong-Kyung; Lim, Jong-Seok

2004-10-31

Immunization with dendritic cells (DCs) pulsed with tumor antigen can activate tumor-specific cytotoxic T lymphocytes (CTL), which is responsible for tumor protection and regression. In this study, we examined whether DCs pulsed with necrotic tumor lysates can efficiently prevent malignant melanoma tumor cell metastasis to the lung. DCs derived from mouse bone marrow were found to produce remarkably elevated levels of IL-12 after being pulsed with the tumor lysates. Moreover, immunization with these DCs induced CTL activation and protected mice from metastasis development by intravenously inoculated tumor cells. In addition, these DCs activated NK cells in vitro in a contact-dependent manner, and induced NK activities in vivo. Furthermore, NK cell depletion before DC vaccination significantly reduced the tumor-specific CTL activity, IFN-gamma production, and IFN-gamma- inducible gene expression, and eventually interfered with the antitumor effect of tumor-pulsed DCs. Finally, similar findings with respect to NK cell dependency were obtained in the C57BL/ 6J-bg/bg mice, which have severe deficiency in cytolytic activity of NK cells. These data suggest that the antitumor effect elicited by DC vaccination, at least in a B16 melanoma model, requires the participation of both cytolytic NK and CD8(+) T cells. The findings of this study would provide important data for the effective design of DC vaccines for cancer immunotherapy.

TLR expression and NK cell activation after human yellow fever vaccination.

PubMed

Neves, Patrícia Cristina da Costa; Matos, Denise Cristina de Souza; Marcovistz, Rugimar; Galler, Ricardo

2009-09-18

The yellow fever vaccine is very effective with a single injection conferring protection for at least 10 years. Recent evidence suggests that the innate immune cells activated through Toll-like receptors (TLRs), are critical determinants of the robustness of the adaptive response. Therefore, we investigated the NK cell status in eight healthy volunteers after vaccination with YF 17DD virus. Shortly after vaccination, we observed increased expression of TLR-3 and TLR-9 in NK cells and markers such as CD69, HLA-DP-DQ-DR, CD38 and CD16. The up-regulation of CD69 was positively correlated with the presence of TLRs throughout the post-vaccination period and the circulating IFN-gamma was significantly augmented. These results suggest that TLRs may play an important role in NK cell activation during the immune response to vaccination, indicating a potential role for NK cells in helping the development of long-lasting protective memory.

Critical role for the chemokine receptor CXCR6 in NK cell-mediated antigen-specific memory of haptens and viruses.

PubMed

Paust, Silke; Gill, Harvinder S; Wang, Bao-Zhong; Flynn, Michael P; Moseman, E Ashley; Senman, Balimkiz; Szczepanik, Marian; Telenti, Amalio; Askenase, Philip W; Compans, Richard W; von Andrian, Ulrich H

2010-12-01

Hepatic natural killer (NK) cells mediate antigen-specific contact hypersensitivity (CHS) in mice deficient in T cells and B cells. We report here that hepatic NK cells, but not splenic or naive NK cells, also developed specific memory of vaccines containing antigens from influenza, vesicular stomatitis virus (VSV) or human immunodeficiency virus type 1 (HIV-1). Adoptive transfer of virus-sensitized NK cells into naive recipient mice enhanced the survival of the mice after lethal challenge with the sensitizing virus but not after lethal challenge with a different virus. NK cell memory of haptens and viruses depended on CXCR6, a chemokine receptor on hepatic NK cells that was required for the persistence of memory NK cells but not for antigen recognition. Thus, hepatic NK cells can develop adaptive immunity to structurally diverse antigens, an activity that requires NK cell-expressed CXCR6.

Proteomic comparison of 3D and 2D glioma models reveals increased HLA-E expression in 3D models is associated with resistance to NK cell-mediated cytotoxicity.

PubMed

He, Weiqi; Kuang, Yongqin; Xing, Xuemin; Simpson, Richard J; Huang, Haidong; Yang, Tao; Chen, Jingmin; Yang, Libin; Liu, Enyu; He, Weifeng; Gu, Jianwen

2014-05-02

Three-dimensional cell culture techniques can better reflect the in vivo characteristics of tumor cells compared with traditional monolayer cultures. Compared with their 2D counterparts, 3D-cultured tumor cells showed enhanced resistance to the cytotoxic T cell-mediated immune response. However, it remains unclear whether 3D-cultured tumor cells have an enhanced resistance to NK cell cytotoxicity. In this study, a total of 363 differentially expressed proteins were identified between the 2D- and 3D-cultured U251 cells by comparative proteomics, and an immune-associated protein-protein interaction (PPI) network based on these differential proteins was constructed by bioinformatics. Within the network, HLA-E, as a molecule for inhibiting NK cell activation, was significantly up-regulated in the 3D-cultured tumor cells. Then, we found that the 3D-cultured U251 cells exhibited potent resistance to NK cell cytotoxicity in vitro and were prone to tumor formation in vivo. The resistance of the 3D-cultured tumor cells to NK cell lysis was mediated by the HLA-E/NKG2A interaction because the administration of antibodies that block either HLA-E or NKG2A completely eliminated this resistance and significantly decreased tumor formation. Taken together, our findings indicate that HLA-E up-regulation in 3D-cultured cells may result in enhanced tumor resistance to NK cell-mediated immune response.

Therapeutic Potential and Challenges of Natural Killer Cells in Treatment of Solid Tumors

PubMed Central

Gras Navarro, Andrea; Björklund, Andreas T.; Chekenya, Martha

2015-01-01

Natural killer (NK) cells are innate lymphoid cells that hold tremendous potential for effective immunotherapy for a broad range of cancers. Due to the mode of NK cell killing, requiring one-to-one target engagement and site-directed release of cytolytic granules, the therapeutic potential of NK cells has been most extensively explored in hematological malignancies. However, their ability to precisely kill antibody coated cells, cancer stem cells, and genotoxically altered cells, while maintaining tolerance to healthy cells makes them appealing therapeutic effectors for all cancer forms, including metastases. Due to their release of pro-inflammatory cytokines, NK cells may potently reverse the anti-inflammatory tumor microenvironment (TME) and augment adaptive immune responses by promoting differentiation, activation, and/or recruitment of accessory immune cells to sites of malignancy. Nevertheless, integrated and coordinated mechanisms of subversion of NK cell activity against the tumor and its microenvironment exist. Although our understanding of the receptor ligand interactions that regulate NK cell functionality has evolved remarkably, the diversity of ligands and receptors is complex, as is their mechanistic foundations in regulating NK cell function. In this article, we review the literature and highlight how the TME manipulates the NK cell phenotypes, genotypes, and tropism to evade tumor recognition and elimination. We discuss counter strategies that may be adopted to augment the efficacy of NK cell anti-tumor surveillance, the clinical trials that have been undertaken so far in solid malignancies, critically weighing the challenges and opportunities with this approach. PMID:25972872

Imaging immune surveillance of individual natural killer cells confined in microwell arrays.

PubMed

Guldevall, Karolin; Vanherberghen, Bruno; Frisk, Thomas; Hurtig, Johan; Christakou, Athanasia E; Manneberg, Otto; Lindström, Sara; Andersson-Svahn, Helene; Wiklund, Martin; Önfelt, Björn

2010-11-12

New markers are constantly emerging that identify smaller and smaller subpopulations of immune cells. However, there is a growing awareness that even within very small populations, there is a marked functional heterogeneity and that measurements at the population level only gives an average estimate of the behaviour of that pool of cells. New techniques to analyze single immune cells over time are needed to overcome this limitation. For that purpose, we have designed and evaluated microwell array systems made from two materials, polydimethylsiloxane (PDMS) and silicon, for high-resolution imaging of individual natural killer (NK) cell responses. Both materials were suitable for short-term studies (<4 hours) but only silicon wells allowed long-term studies (several days). Time-lapse imaging of NK cell cytotoxicity in these microwell arrays revealed that roughly 30% of the target cells died much more rapidly than the rest upon NK cell encounter. This unexpected heterogeneity may reflect either separate mechanisms of killing or different killing efficiency by individual NK cells. Furthermore, we show that high-resolution imaging of inhibitory synapse formation, defined by clustering of MHC class I at the interface between NK and target cells, is possible in these microwells. We conclude that live cell imaging of NK-target cell interactions in multi-well microstructures are possible. The technique enables novel types of assays and allow data collection at a level of resolution not previously obtained. Furthermore, due to the large number of wells that can be simultaneously imaged, new statistical information is obtained that will lead to a better understanding of the function and regulation of the immune system at the single cell level.

The expression of human natural killer cell receptors in early life.

PubMed

Sundström, Y; Nilsson, C; Lilja, G; Kärre, K; Troye-Blomberg, M; Berg, L

2007-01-01

Natural killer (NK) cells play an important role in tumour immunosurveillance and the early defence against viral infections. Recognition of altered cells (i.e. infected- or tumour-cells) is achieved through a multiple receptor recognition strategy which gives the NK cells inhibitory or activating signals depending on the ligands present on the target cell. NK cells originate from the bone marrow where they develop and proliferate. However, further maturation processes and homeostasis of NK cells in peripheral blood are not well understood. To determine the proportions of cells and the expression of NK cell receptors, mononuclear cells from children at three time points during early childhood were compared, i.e. cord blood (CB), 2 and 5 years of age. The proportion of NK cells was high in CB, but the interferon-gamma (IFN-gamma) production low compared to later in life. In contrast, the proportion of T cells was low in CB. This may indicate a deviation of the regulatory function of NK cells in CB compared to later in life, implying an importance of innate immunity in early life before the adaptive immune system matures. Additionally, we found that the proportion of LIR-1(+) NK cells increased with increasing age while CD94(+)NKG2C(-) (NKG2A(+)) NK cells and the level of expression of NKG2D, NKp30 and NKp46 decreased with age. These age related changes in NK cell populations defined by the expression of activating and inhibitory receptors may be the result of pathogen exposure and/or a continuation of the maturation process that begins in the bone marrow.

Development of the adaptive NK cell response to human cytomegalovirus in the context of aging.

PubMed

López-Botet, Miguel; Muntasell, Aura; Martínez-Rodríguez, José E; López-Montañés, María; Costa-García, Marcel; Pupuleku, Aldi

2016-09-01

Human cytomegalovirus (HCMV) establishes a highly prevalent life-long latent infection. Though generally subclinical, HCMV infection may have severe consequences during fetal development and in immunocompromised individuals. Based on epidemiological studies HCMV(+) serology has been associated with the development of atherosclerosis, immune senescence and an increase mortality rate in elderly people. Such long-term detrimental effects of the viral infection presumably result from an inefficient immune control of the pathogen, depending on the quality and evolution of the individual host-pathogen relationship. Together with antigen-specific T lymphocytes, NK cells play an important role in anti-viral immune defense. HCMV promotes in some individuals the differentiation and persistent steady state expansion of an NK cell subset bearing the CD94/NKG2C activating receptor. The relationship between this adaptive NK cell response to HCMV and aging is overviewed. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Low baseline levels of NK cells may predict a positive response to ipilimumab in melanoma therapy.

PubMed

Tietze, Julia K; Angelova, Daniela; Heppt, Markus V; Ruzicka, Thomas; Berking, Carola

2017-07-01

The introduction of immune checkpoint blockade (ICB) has been a breakthrough in the therapy of metastatic melanoma. The influence of ICB on T-cell populations has been studied extensively, but little is known about the effect on NK cells. In this study, we analysed the relative and absolute amounts of NK cells and of the subpopulations of CD56 dim and CD56 bright NK cells among the peripheral blood mononuclear cells (PBMCs) of 32 patients with metastatic melanoma before and under treatment with ipilimumab or pembrolizumab by flow cytometry. In 15 (47%) patients, an abnormal low amount of NK cells was found at baseline. Analysis of the subpopulations showed also low or normal baseline levels for CD56 dim NK cells, whereas the baseline levels of CD56 bright NK cells were either normal or abnormally high. The relative and absolute amounts of NK cells and of CD56 dim and CD56 bright NK cell subpopulations in patients with a normal baseline did not change under treatment. However, patients with a low baseline of NK cells and CD56 dim NK cells showed a significant increase in these immune cell subsets, but the amounts remained to be lower than the normal baseline. The amount of CD56 bright NK cells was unaffected by treatment. The baseline levels of NK cells were correlated with the number of metastatic organs. Their proportion increased, whereas the expression of NKG2D decreased significantly when more than one organ was affected by metastases. Low baseline levels of NK cells and CD56 dim NK cells as well as normal baseline levels of CD56 bright NK cells correlated significantly with a positive response to ipilimumab but not to pembrolizumab. Survival curves of patients with low amounts of CD56 dim NK cells treated with ipilimumab showed a trend to longer survival. Normal baseline levels of CD56 bright NK cells were significantly correlated with longer survival as compared to patients with high baseline levels. In conclusion, analysis of the amounts of total NK cells and of CD56 dim and CD56 bright NK cells subpopulations at baseline may help to predict the outcome of treatment with ipilimumab. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The CD94/NKG2C-expressing NK cell subset is augmented in chronic lymphocytic leukemia patients with positive human cytomegalovirus serostatus.

PubMed

Petersen, Line; Roug, Anne S; Skovbo, Anni; Thysen, Anna H; Eskelund, Christian W; Hokland, Marianne E

2009-10-01

Human cytomegalovirus (HCMV) manipulates the host immune system in various ways. Allegedly, HCMV infection is associated with increased percentages of a particular natural killer (NK) cell subset expressing the activating receptor CD94/NKG2C in both healthy individuals and in patients infected with human immunodeficiency virus (HIV). Whether the HCMV-mediated induction of this specific NK cell subset is also apparent for other diseases characterized by abnormal immune responses, such as malignant blood diseases, is unknown. By comparing the fractions of CD94/NKG2C(+) NK cells in B-cell chronic lymphocytic leukemia (B-CLL) patients having either positive or negative HCMV serostatus, a proportional increase of this cell subset was obvious in the HCMV-seropositive subjects. Therapeutic intervention in the patients with positive HCMV serostatus did not seem to reduce the percentage of CD94/NKG2C-expressing NK cells. Thus, HCMV infection seemingly shapes the NK cell system in healthy individuals, HIV patients, and B-CLL patients in a uniform manner, even though these involve different immunological challenges.

Genetic deletion of Cxcl14 in mice alters uterine NK cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cao, Qichen; Graduate School of the Chinese Academy of Sciences, 19 Yuquan Road, Shijingshan, Beijing 100049; Chen, Hua

2013-06-14

Highlights: •We first examined the expression of Cxcl14 in MLAp and DB of uterus. •We found the uNK cells in MLAp and decidua express Cxcl14. •In Cxcl14{sup −/−} placenta, we found significantly decreased uNK cells. •We first performed microarray to compare the gene expression in MLAp and DB. -- Abstract: The uterine natural killer cells (uNK cells) are the major immune cells in pregnant uterus and the number of uNK cells is dramatically increased during placentation and embryo development. The uNK cells are necessary for the immune tolerance, cytokine secretion and angiogenesis of placenta. Former studies indicated that the populationmore » expansion of uNK cells was accomplished through recruitment of NK cell precursors from the spleen and bone marrow, but not proliferation of NK cells. However, the necessary molecules within this process were little understood. Here in our study, we found the co-localized expression of Cxcl14 protein with uNK cells in E13.5 pregnant uterus. Moreover, we used Cxcl14 knockout mice to examine uNK cells in mesometrial lymphoid aggregate of pregnancy (MLAp) and decidua basalis (DB) of E13.5 pregnant uterus and found significantly decreased uNK cells in Cxcl14{sup −/−} pregnant uteri compared with Cxcl14{sup +/−} pregnant uteri. To further explorer the molecular change in MLAp and DB after Cxcl14 knockout, we isolated the MLAp and DB from Cxcl14{sup +/+} and Cxcl14{sup −/−} pregnant uteri and performed microarray analysis. We found many genes were up and down regulated after Cxcl14 knockout. In conclusion, our results suggested the important function of Cxcl14 in uNK cells and the proper level of Cxcl14 protein were required to recruit NK cells to pregnant uterus.« less

Modification of P-selectin glycoprotein ligand-1 with a natural killer cell-restricted sulfated lactosamine creates an alternate ligand for L-selectin

PubMed Central

André, Pascale; Spertini, Olivier; Guia, Sophie; Rihet, Pascal; Dignat-George, Françoise; Brailly, Hervé; Sampol, José; Anderson, Paul J.; Vivier, Eric

2000-01-01

Natural killer (NK) cells are components of the innate immune system that can recognize and kill virally infected cells, tumor cells, and allogeneic cells without prior sensitization. NK cells also elaborate cytokines (e.g., interferon-γ and tumor necrosis factor-α) and chemokines (e.g., macrophage inflammatory protein-1α) that promote the acquisition of antigen-specific immunity. NK cell differentiation is accompanied by the cell surface expression of a mucin-like glycoprotein bearing an NK cell-restricted keratan sulfate-related lactosamine carbohydrate, the PEN5 epitope. Here, we report that PEN5 is a post-translational modification of P-selectin glycoprotein ligand-1 (PSGL-1). The PEN5 epitope creates on PSGL-1 a unique binding site for L-selectin, which is independent of PSGL-1 tyrosine sulfation. On the surface of NK cells, the expression of PEN5 is coordinated with the disappearance of L-selectin and the up-regulation of Killer cell Ig-like Receptors (KIR). These results indicate that NK cell differentiation is accompanied by the acquisition of a unique carbohydrate, PEN5, that can serve as part of a combination code to deliver KIR+ NK cells to specific tissues. PMID:10725346

Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity.

PubMed

Zhang, Congcong; Oberoi, Pranav; Oelsner, Sarah; Waldmann, Anja; Lindner, Aline; Tonn, Torsten; Wels, Winfried S

2017-01-01

Significant progress has been made in recent years toward realizing the potential of natural killer (NK) cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs) composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future prospects of CAR-engineered NK-92 cells as off-the-shelf cellular therapeutics, with special emphasis on ErbB2 (HER2)-specific NK-92 cells that are approaching clinical application.

Chimeric Antigen Receptor-Engineered NK-92 Cells: An Off-the-Shelf Cellular Therapeutic for Targeted Elimination of Cancer Cells and Induction of Protective Antitumor Immunity

PubMed Central

Zhang, Congcong; Oberoi, Pranav; Oelsner, Sarah; Waldmann, Anja; Lindner, Aline; Tonn, Torsten; Wels, Winfried S.

2017-01-01

Significant progress has been made in recent years toward realizing the potential of natural killer (NK) cells for cancer immunotherapy. NK cells can respond rapidly to transformed and stressed cells and have the intrinsic potential to extravasate and reach their targets in almost all body tissues. In addition to donor-derived primary NK cells, also the established NK cell line NK-92 is being developed for adoptive immunotherapy, and general safety of infusion of irradiated NK-92 cells has been established in phase I clinical trials with clinical responses observed in some of the cancer patients treated. To enhance their therapeutic utility, NK-92 cells have been modified to express chimeric antigen receptors (CARs) composed of a tumor-specific single chain fragment variable antibody fragment fused via hinge and transmembrane regions to intracellular signaling moieties such as CD3ζ or composite signaling domains containing a costimulatory protein together with CD3ζ. CAR-mediated activation of NK cells then bypasses inhibitory signals and overcomes NK resistance of tumor cells. In contrast to primary NK cells, CAR-engineered NK-92 cell lines suitable for clinical development can be established from molecularly and functionally well-characterized single cell clones following good manufacturing practice-compliant procedures. In preclinical in vitro and in vivo models, potent antitumor activity of NK-92 variants targeted to differentiation antigens expressed by hematologic malignancies, and overexpressed or mutated self-antigens associated with solid tumors has been found, encouraging further development of CAR-engineered NK-92 cells. Importantly, in syngeneic mouse tumor models, induction of endogenous antitumor immunity after treatment with CAR-expressing NK-92 cells has been demonstrated, resulting in cures and long-lasting immunological memory protecting against tumor rechallenge at distant sites. Here, we summarize the current status and future prospects of CAR-engineered NK-92 cells as off-the-shelf cellular therapeutics, with special emphasis on ErbB2 (HER2)-specific NK-92 cells that are approaching clinical application. PMID:28572802

Dok1 and Dok2 proteins regulate natural killer cell development and function

PubMed Central

Celis-Gutierrez, Javier; Boyron, Marilyn; Walzer, Thierry; Pandolfi, Pier Paolo; Jonjić, Stipan; Olive, Daniel; Dalod, Marc; Vivier, Eric; Nunès, Jacques A

2014-01-01

Natural killer (NK) cells are involved in immune responses against tumors and microbes. NK-cell activation is regulated by intrinsic and extrinsic mechanisms that ensure NK tolerance and efficacy. Here, we show that the cytoplasmic signaling molecules Dok1 and Dok2 are tyrosine phosphorylated upon NK-cell activation. Overexpression of Dok proteins in human NK cells reduces cell activation induced by NK-cell-activating receptors. Dok1 and Dok2 gene ablation in mice induces an NK-cell maturation defect and leads to increased IFN-γ production induced by activating receptors. Taken together, these results reveal that Dok1 and Dok2 proteins are involved in an intrinsic negative feedback loop downstream of NK-cell-activating receptors in mouse and human. PMID:24963146

Selection of an HLA-C*03:04-Restricted HIV-1 p24 Gag Sequence Variant Is Associated with Viral Escape from KIR2DL3+ Natural Killer Cells: Data from an Observational Cohort in South Africa.

PubMed

Hölzemer, Angelique; Thobakgale, Christina F; Jimenez Cruz, Camilo A; Garcia-Beltran, Wilfredo F; Carlson, Jonathan M; van Teijlingen, Nienke H; Mann, Jaclyn K; Jaggernath, Manjeetha; Kang, Seung-gu; Körner, Christian; Chung, Amy W; Schafer, Jamie L; Evans, David T; Alter, Galit; Walker, Bruce D; Goulder, Philip J; Carrington, Mary; Hartmann, Pia; Pertel, Thomas; Zhou, Ruhong; Ndung'u, Thumbi; Altfeld, Marcus

2015-11-01

Viruses can evade immune surveillance, but the underlying mechanisms are insufficiently understood. Here, we sought to understand the mechanisms by which natural killer (NK) cells recognize HIV-1-infected cells and how this virus can evade NK-cell-mediated immune pressure. Two sequence mutations in p24 Gag associated with the presence of specific KIR/HLA combined genotypes were identified in HIV-1 clade C viruses from a large cohort of infected, untreated individuals in South Africa (n = 392), suggesting viral escape from KIR+ NK cells through sequence variations within HLA class I-presented epitopes. One sequence polymorphism at position 303 of p24 Gag (TGag303V), selected for in infected individuals with both KIR2DL3 and HLA-C*03:04, enabled significantly better binding of the inhibitory KIR2DL3 receptor to HLA-C*03:04-expressing cells presenting this variant epitope compared to the wild-type epitope (wild-type mean 18.01 ± 10.45 standard deviation [SD] and variant mean 44.67 ± 14.42 SD, p = 0.002). Furthermore, activation of primary KIR2DL3+ NK cells from healthy donors in response to HLA-C*03:04+ target cells presenting the variant epitope was significantly reduced in comparison to cells presenting the wild-type sequence (wild-type mean 0.78 ± 0.07 standard error of the mean [SEM] and variant mean 0.63 ± 0.07 SEM, p = 0.012). Structural modeling and surface plasmon resonance of KIR/peptide/HLA interactions in the context of the different viral sequence variants studied supported these results. Future studies will be needed to assess processing and antigen presentation of the investigated HIV-1 epitope in natural infection, and the consequences for viral control. These data provide novel insights into how viruses can evade NK cell immunity through the selection of mutations in HLA-presented epitopes that enhance binding to inhibitory NK cell receptors. Better understanding of the mechanisms by which HIV-1 evades NK-cell-mediated immune pressure and the functional validation of a structural modeling approach will facilitate the development of novel targeted immune interventions to harness the antiviral activities of NK cells.

Deficient mitochondrial biogenesis in IL-2 activated NK cells correlates with impaired PGC1-α upregulation in elderly humans.

PubMed

Miranda, Dante; Jara, Claudia; Mejias, Sophia; Ahumada, Viviana; Cortez-San Martin, Marcelo; Ibañez, Jorge; Hirsch, Sandra; Montoya, Margarita

2018-05-18

Immunosenescence has been described as age-associated changes in the immune function which are thought to be responsible for the increased morbidity with age. Human Natural Killer (NK) cells are a specialized heterogeneous subpopulation of lymphocytes involved in immune defense against tumor and microbial diseases. Interestingly, aging-related NK cell dysfunction is associated with features of aging such as tumor incidence, reduced vaccination efficacy, and short survival due to infection. It is known that NK cell effector functions are critically dependent on cytokines and metabolic activity. Our aim was to determine whether there is a difference in purified human NK cell function in response to high concentration of IL-2 between young and elder donors. Here, we report that the stimulation of human NK cells with IL-2 (2000 U/mL) enhance NK cell cytotoxic activity from both young and elderly donors. However, while NK cells from young people responded to IL-2 signaling by increasing mitochondrial mass and mitochondrial membrane potential, no increase in these mitochondrial functional parameters was seen in purified NK cells from elderly subjects. Moreover, as purified NK cells from the young exhibited an almost three-fold increase in PGC-1α expression after IL-2 (2000 U/mL) stimulation, PGC-1α expression was inhibited in purified NK cells from elders. Furthermore, this response upon PGC-1α expression after IL-2 stimulation promoted an increase in ROS production in NK cells from elderly humans, while no increase in ROS production was observed in NK cells of young donors. Our data show that IL-2 stimulates NK cell effector function through a signaling pathway which involves a PGC-1α-dependent mitochondrial function in young NK cells, however it seems that NK cells from older donors exhibit an altered IL-2 signaling which affects mitochondrial function associated with an increased production of ROS which could represent a feature of NK cell senescence. Copyright © 2018 Elsevier Inc. All rights reserved.

The Rise of Allogeneic Natural Killer Cells As a Platform for Cancer Immunotherapy: Recent Innovations and Future Developments

PubMed Central

Veluchamy, John P.; Kok, Nina; van der Vliet, Hans J.; Verheul, Henk M. W.; de Gruijl, Tanja D.; Spanholtz, Jan

2017-01-01

Natural killer (NK) cells are critical immune effector cells in the fight against cancer. As NK cells in cancer patients are highly dysfunctional and reduced in number, adoptive transfer of large numbers of cytolytic NK cells and their potential to induce relevant antitumor responses are widely explored in cancer immunotherapy. Early studies from autologous NK cells have failed to demonstrate significant clinical benefit. In this review, the clinical benefits of adoptively transferred allogeneic NK cells in a transplant and non-transplant setting are compared and discussed in the context of relevant NK cell platforms that are being developed and optimized by various biotech industries with a special focus on augmenting NK cell functions. PMID:28620386

Plasmodium falciparum-Infected Erythrocytes Induce Granzyme B by NK Cells through Expression of Host-Hsp70

PubMed Central

Böttger, Evelyn; Multhoff, Gabriele; Kun, Jürgen F. J.; Esen, Meral

2012-01-01

In the early immune response to Plasmodium falciparum-infected erythrocytes (iRBC), Natural Killer (NK) cells are activated, which suggests an important role in innate anti-parasitic immunity. However, it is not well understood whether NK cells directly recognize iRBC or whether stimulation of NK cells depends mainly on activating signals from accessory cells through cell-to-cell contact or soluble factors. In the present study, we investigated the influence of membrane-bound host Heat shock protein (Hsp) 70 in triggering cytotoxicity of NK cells from malaria-naïve donors or the cell line NK92 against iRBC. Hsp70 and HLA-E membrane expression on iRBC and potential activatory NK cell receptors (NKG2C, CD94) were assessed by flow cytometry and immunoblot. Upon contact with iRBC, Granzyme B (GzmB) production and release was initiated by unstimulated and Hsp70-peptide (TKD) pre-stimulated NK cells, as determined by Western blot, RT-PCR and ELISPOT analysis. Eryptosis of iRBC was determined by Annexin V-staining. Our results suggest that presence of Hsp70 and absence of HLA-E on the membrane of iRBC prompt the infected host cells to become targets for NK cell-mediated cytotoxicity, as evidenced by impaired parasite development. Contact of iRBC with NK cells induced release of GzmB. We propose that following GzmB uptake, iRBC undergo eryptosis via a perforin-independent, GzmB-mediated mechanism. Since NK activity toward iRBC could be specifically enhanced by TKD peptide and abrogated to baseline levels by blocking Hsp70 exposure, we propose TKD as an innovative immunostimulatory agent to be tested as an adjunct to anti-parasitic treatments in vivo. PMID:22438997

Plasmodium falciparum-infected erythrocytes induce granzyme B by NK cells through expression of host-Hsp70.

PubMed

Böttger, Evelyn; Multhoff, Gabriele; Kun, Jürgen F J; Esen, Meral

2012-01-01

In the early immune response to Plasmodium falciparum-infected erythrocytes (iRBC), Natural Killer (NK) cells are activated, which suggests an important role in innate anti-parasitic immunity. However, it is not well understood whether NK cells directly recognize iRBC or whether stimulation of NK cells depends mainly on activating signals from accessory cells through cell-to-cell contact or soluble factors. In the present study, we investigated the influence of membrane-bound host Heat shock protein (Hsp) 70 in triggering cytotoxicity of NK cells from malaria-naïve donors or the cell line NK92 against iRBC. Hsp70 and HLA-E membrane expression on iRBC and potential activatory NK cell receptors (NKG2C, CD94) were assessed by flow cytometry and immunoblot. Upon contact with iRBC, Granzyme B (GzmB) production and release was initiated by unstimulated and Hsp70-peptide (TKD) pre-stimulated NK cells, as determined by Western blot, RT-PCR and ELISPOT analysis. Eryptosis of iRBC was determined by Annexin V-staining. Our results suggest that presence of Hsp70 and absence of HLA-E on the membrane of iRBC prompt the infected host cells to become targets for NK cell-mediated cytotoxicity, as evidenced by impaired parasite development. Contact of iRBC with NK cells induced release of GzmB. We propose that following GzmB uptake, iRBC undergo eryptosis via a perforin-independent, GzmB-mediated mechanism. Since NK activity toward iRBC could be specifically enhanced by TKD peptide and abrogated to baseline levels by blocking Hsp70 exposure, we propose TKD as an innovative immunostimulatory agent to be tested as an adjunct to anti-parasitic treatments in vivo.

Interferon-gamma: biologic functions and HCV therapy (type I/II) (1 of 2 parts).

PubMed

Gattoni, A; Parlato, A; Vangieri, B; Bresciani, M; Derna, R

2006-01-01

This review is aimed at exhaustively presenting and discussing the interferon-gamma (IFN-gamma), a cytokine that plays an important role in inducing and modulating an array of immune responses. A review of the most significant and recent clinical trials was performed. Although IFN-gamma has some antiviral activity, it is much less active in this regard than type I IFNs. IFN-gamma is involved in the regulation of nearly all phases of the immune and inflammatory responses, including the activation and differentiation of T cells, B cells, NK cells, macrophages, and others. It is therefore best regarded as a distint immunoregulatory cytokine. IFN-gamma secretion is a hallmark of Th1 lymphocytes. It is also secreted by nearly all CD8 T cells, by some Th0 cells, and by NK cells. Each of these cell types secretes IFN-gamma only when activated, usually as part of immune response and especially in response to IL-2 and IL-12. IFN-gamma production is inhibited by IL-4, IL-10, TGFbeta, glucocorticoids, cyclosporin A and FK506. Nearly all cell types express the heterodimeric receptor for IFN-beta and respond to this cytokine by increasing the surface expression of class I MHC proteins. As a result, virtually any cell in the vicinity of an IFN-beta-secreting cell becomes more efficient at presenting endogenous antigens and hence a better target for cytotoxic killing if it harbors an intracellular pathogen. Unlike the type I IFNs, IFN-gamma also increases the expression of class II MHC proteins on professional APCs, and so promotes antigen presentation to helper T cells as well. It also induces de novo expression of class II MHC proteins on venular endothelial cells and on some other epithelial and connective tissue cells that do not otherwise express them, thus enabling these cell types to function as temporary APCs at sites of intense immune reactions. The effector functions of NK cells are to lyse virus-infected cells and to secrete IFN-gamma, which activates macrofages to destroy phagocytosed microbes. The mechanism of NK cell-mediates cytolysis is essentially the same as that of cytolysis by CTLS. NK cells lyse virally infected cells before antigen specific CTLS came become fully active, that is, during the first few days after viral infection. NK cells are expanded and activated by cytokines of innate immunity, such as IL-12 and IL-15, and they kill infected cells, especially those that display reduced levels of class I molecoles. Some tumors, especially those of hematopoietic origin, are targets of NK cells, perlevels or types of class I MHC molecules. Therefore, IFN-gamma serves critical functions in innate immunity and in specific cell-mediated immunity (in addition, IFN activates neutrophilis and stimulates the cytolitic activity of NK cells). Many IFNs-gamma induced effects result in heigtened immune surveillance. IFN-gamma is a remarkable cytokine that orchestrates many distinct cellular programs through transcriptional control over large numbers of genes. Many IFNs-gamma-induced effects resulting in heightend immune surveillance and immune system function during infection have been discussed in this review. As the pathogens (microorganism with the potential to cause tissue injury or disease) augment local IFN-gamma production, and IFN-gamma augments the immune system response, an important function of IFN-gamma during in vivo infection is suggested. IFN-gamma is primarily secreted by activated T cells and natural killer cells, and can promote macrophage activation, mediate antiviral e antibacterial immunity, enhance antigen presentation, orchestrate activation of the innate immune system, coordinate lymphocyte-endothelium interaction, regulate Th1/Th2 balance, and control cellular proliferation and apoptosis.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seong, Yeon-Jae; Hafis Clinic, Seoul; Sung, Pil Soo

Cellular prion protein (PrP{sup C}) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP{sup C} in the immune system have not been clearly elucidated. In the present study, we investigated the effects of a soluble form of recombinant PrP{sup C} protein on human natural killer (NK) cells. Recombinant soluble PrP{sup C} protein was generated by fusion of human PrP{sup C} with the Fc portion of human IgG{sub 1} (PrP{sup C}-Fc). PrP{sup C}-Fc binds to the surface of human NK cells, particularly to CD56{sup dim} NK cells. PrP{sup C}-Fc induced themore » production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP{sup C}-Fc facilitated the IL-15-induced proliferation of NK cells. PrP{sup C}-Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP{sup C}-Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP{sup C} (PrP{sup C}-Fc) was generated by fusion of human PrP{sup C} with IgG1 Fc portion. • PrP{sup C}-Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP{sup C}-Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP{sup C}-Fc protein activates human NK cells via the ERK and JNK signaling pathways.« less

Protective antitumor activity through dendritic cell immunization is mediated by NK cell as well as CTL activation.

PubMed

Kim, K D; Kim, J K; Kim, S J; Choe, I S; Chung, T H; Choe, Y K; Lim, J S

1999-08-01

Dendritic cells (DCs) are potent professional antigen-presenting cells (APC) capable of inducing the primary T cell response to antigen. Although tumor cells express target antigens, they are incapable of stimulating a tumor-specific immune response due to a defect in the costimulatory signal that is required for optimal activation of T cells. In this work, we describe a new approach using tumor-DC coculture to improve the antigen presenting capacity of tumor cells, which does not require a source of tumor-associated antigen. Immunization of a weakly immunogenic and progressive tumor cocultured with bone marrow-derived DCs generated an effective tumor vaccine. Immunization with the cocultured DCs was able to induce complete protective immunity against tumor challenges and was effective for the induction of tumor-specific CTL (cytotoxic T lymphocyte) activity. Furthermore, high NK cell activity was observed in mice in which tumors were rejected. In addition, immunization with tumor-pulsed DCs induced delayed tumor growth, but not tumor eradication in tumor-bearing mice. Our results demonstrate that coculture of DCs with tumors generated antitumor immunity due to the NK cell activation as well as tumor-specific T cell. This approach would be useful for designing tumor vaccines using DCs when the information about tumor antigens is limited.

Two alternate strategies for innate immunity to Epstein-Barr virus: One using NK cells and the other NK cells and γδ T cells

PubMed Central

Horowitz, Amir; Nemat-Gorgani, Neda; Münz, Christian

2017-01-01

Most humans become infected with Epstein–Barr virus (EBV), which then persists for life. Infrequently, EBV infection causes infectious mononucleosis (IM) or Burkitt lymphoma (BL). Type I EBV infection, particularly type I BL, stimulates strong responses of innate immune cells. Humans respond to EBV in two alternative ways. Of 24 individuals studied, 13 made strong NK and γδ T cell responses, whereas 11 made feeble γδ T cell responses but stronger NK cell responses. The difference does not correlate with sex, HLA type, or previous exposure to EBV or cytomegalovirus. Cohorts of EBV+ children and pediatric IM patients include both group 1 individuals, with high numbers of γδ T cells, and group 2 individuals, with low numbers. The even balance of groups 1 and 2 in the human population points to both forms of innate immune response to EBV having benefit for human survival. Correlating these distinctive responses with the progress of EBV infection might facilitate the management of EBV-mediated disease. PMID:28468758

Natural Killer Cells in Antifungal Immunity.

PubMed

Schmidt, Stanislaw; Tramsen, Lars; Lehrnbecher, Thomas

2017-01-01

Invasive fungal infections are still an important cause of morbidity and mortality in immunocompromised patients such as patients suffering from hematological malignancies or patients undergoing hematopoietic stem cell transplantion. In addition, other populations such as human immunodeficiency virus-patients are at higher risk for invasive fungal infection. Despite the availability of new antifungal compounds and better supportive care measures, the fatality rate of invasive fungal infection remained unacceptably high. It is therefore of major interest to improve our understanding of the host-pathogen interaction to develop new therapeutic approaches such as adoptive immunotherapy. As experimental methodologies have improved and we now better understand the complex network of the immune system, the insight in the interaction of the host with the fungus has significantly increased. It has become clear that host resistance to fungal infections is not only associated with strong innate immunity but that adaptive immunity (e.g., T cells) also plays an important role. The antifungal activity of natural killer (NK) cells has been underestimated for a long time. In vitro studies demonstrated that NK cells from murine and human origin are able to attack fungi of different genera and species. NK cells exhibit not only a direct antifungal activity via cytotoxic molecules but also an indirect antifungal activity via cytokines. However, it has been show that fungi exert immunosuppressive effects on NK cells. Whereas clinical data are scarce, animal models have clearly demonstrated that NK cells play an important role in the host response against invasive fungal infections. In this review, we summarize clinical data as well as results from in vitro and animal studies on the impact of NK cells on fungal pathogens.

Primary adrenal insufficiency is associated with impaired natural killer cell function: a potential link to increased mortality.

PubMed

Bancos, Irina; Hazeldine, Jon; Chortis, Vasileios; Hampson, Peter; Taylor, Angela E; Lord, Janet M; Arlt, Wiebke

2017-04-01

Mortality in patients with primary adrenal insufficiency (PAI) is significantly increased, with respiratory infections as a major cause of death. Moreover, patients with PAI report an increased rate of non-fatal infections. Neutrophils and natural killer (NK) cells are innate immune cells that provide frontline protection against invading pathogens. Thus, we compared the function and phenotype of NK cells and neutrophils isolated from PAI patients and healthy controls to ascertain whether altered innate immune responses could be a contributory factor for the increased susceptibility of PAI patients to infection. We undertook a cross-sectional study of 42 patients with PAI due to autoimmune adrenalitis ( n =  37) or bilateral adrenalectomy ( n =  5) and 58 sex- and age-matched controls. A comprehensive screen of innate immune function, consisting of measurements of neutrophil phagocytosis, reactive oxygen species production, NK cell cytotoxicity (NKCC) and NK cell surface receptor expression, was performed on all subjects. Neutrophil function did not differ between PAI and controls. However, NKCC was significantly reduced in PAI (12.0 ± 1.5% vs 21.1 ± 2.6%, P  < 0.0001). Phenotypically, the percentage of NK cells expressing the activating receptors NKG2D and NKp46 was significantly lower in PAI, as was the surface density of NKG2D (all P  < 0.0001). Intracellular granzyme B expression was significantly increased in NK cells from PAI patients ( P  < 0.01). Adrenal insufficiency is associated with significantly decreased NKCC, thereby potentially compromising early recognition and elimination of virally infected cells. This potential impairment in anti-viral immune defense may contribute to the increased rate of respiratory infections and ultimately mortality in PAI. © 2017 The authors.

Neurokinin-1 receptor: functional significance in the immune system in reference to selected infections and inflammation

PubMed Central

Douglas, Steven D.; Leeman, Susan E.

2010-01-01

The G-protein coupled receptor (GPCR), Neurokinin-1 Receptor (NK1R), and its preferred ligand, substance P (SP), are reviewed in relationship to the immune system and selected infections. NK1R and substance P are ubiquitous throughout the animal kingdom. This important pathway has unique functions in numerous cells and tissues. The interaction of SP with its preferred receptor, NK1R, leads to the activation of nuclear factor-kappa-b (NF-κb) and proinflammatory cytokines. NK1R has two isoforms, both a full-length and a truncated form. These isoforms have different functional significances and differ in cell signaling capability. The proinflammatory signals modulated by substance P are important in bacterial, viral, fungal, and parasitic diseases, as well as in immune system function. The SP-NK1R system is a major Class 1, rhodopsin-like GPCR ligand-receptor interaction. PMID:21091716

Natural killer cells as a promising tool to tackle cancer-A review of sources, methodologies, and potentials.

PubMed

Preethy, Senthilkumar; Dedeepiya, Vidyasagar Devaprasad; Senthilkumar, Rajappa; Rajmohan, Mathaiyan; Karthick, Ramalingam; Terunuma, Hiroshi; Abraham, Samuel J K

2017-07-04

Immune cell-based therapies are emerging as a promising tool to tackle malignancies, both solid tumors and selected hematological tumors. Vast experiences in literature have documented their safety and added survival benefits when such cell-based therapies are combined with the existing treatment options. Numerous methodologies of processing and in vitro expansion protocols of immune cells, such as the dendritic cells, natural killer (NK) cells, NKT cells, αβ T cells, so-called activated T lymphocytes, γδ T cells, cytotoxic T lymphocytes, and lymphokine-activated killer cells, have been reported for use in cell-based therapies. Among this handful of immune cells of significance, the NK cells stand apart from the rest for not only their direct cytotoxic ability against cancer cells but also their added advantage, which includes their capability of (i) action through both innate and adaptive immune mechanism, (ii) tackling viruses too, giving benefits in conditions where viral infections culminate in cancer, and (iii) destroying cancer stem cells, thereby preventing resistance to chemotherapy and radiotherapy. This review thoroughly analyses the sources of such NK cells, methods for expansion, and the future potentials of taking the in vitro expanded allogeneic NK cells with good cytotoxic ability as a drug for treating cancer and/or viral infection and even as a prophylactic tool for prevention of cancer after initial remission.

Targeting Ewing sarcoma with activated and GD2-specific chimeric antigen receptor-engineered human NK cells induces upregulation of immune-inhibitory HLA-G

PubMed Central

Kailayangiri, Sareetha; Jamitzky, Silke; Schelhaas, Sonja; Jacobs, Andreas H.; Wiek, Constanze; Hanenberg, Helmut; Hartmann, Wolfgang; Wiendl, Heinz; Pankratz, Susann; Meltzer, Jutta; Farwick, Nicole; Greune, Lea; Fluegge, Maike; Rossig, Claudia

2017-01-01

ABSTRACT Activated and in vitro expanded natural killer (NK) cells have substantial cytotoxicity against many tumor cells, but their in vivo efficacy to eliminate solid cancers is limited. Here, we used chimeric antigen receptors (CARs) to enhance the activity of NK cells against Ewing sarcomas (EwS) in a tumor antigen-specific manner. Expression of CARs directed against the ganglioside antigen GD2 in activated NK cells increased their responses to GD2+ allogeneic EwS cells in vitro and overcame resistance of individual cell lines to NK cell lysis. Second-generation CARs with 4-1BB and 2B4 co-stimulatory signaling and third-generation CARs combining both co-stimulatory domains were all equally effective. By contrast, adoptive transfer of GD2-specific CAR gene-modified NK cells both by intratumoral and intraperitoneal delivery failed to eliminate GD2-expressing EwS xenografts. Histopathology review revealed upregulation of the immunosuppressive ligand HLA-G in tumor autopsies from mice treated with NK cells compared to untreated control mice. Supporting the relevance of this finding, in vitro co-incubation of NK cells with allogeneic EwS cells induced upregulation of the HLA-G receptor CD85j, and HLA-G1 expressed by EwS cells suppressed the activity of NK cells from three of five allogeneic donors against the tumor cells in vitro. We conclude that HLA-G is a candidate immune checkpoint in EwS where it can contribute to resistance to NK cell therapy. HLA-G deserves evaluation as a potential target for more effective immunotherapeutic combination regimens in this and other cancers. PMID:28197367

NK-92 cell, another ideal carrier for chimeric antigen receptor.

PubMed

Wang, Wan-Ning; Zhou, Guang-Yu; Zhang, Wen-Long

2017-08-01

The remarkable clinical outcomes of the treatment for B-cell malignancies through the application of CD19 chimeric antigen receptor T (CAR-T) cells have made adoptive immunotherapy with genetically modified immune effector cells a hotspot in the field of antitumor. However, numerous toxicities of CAR-T cells have been identified. Thus, some studies have resorted to another cytotoxic cell, NK-92 cell, to reach for better efficacy with minimal toxicity. Preclinical studies have confirmed the safety and feasibility of the genetically modified NK-92 cells with highly specific cytotoxicity in vitro and in vivo. Therefore, it is expected that NK-92 cell becomes another ideal carrier for CAR for its unique advantages over primary NK cells, parental NK-92 cells and autologous T cells.

Functionally Diverse NK-Like T Cells Are Effectors and Predictors of Successful Aging

PubMed Central

Michel, Joshua J.; Griffin, Patricia; Vallejo, Abbe N.

2016-01-01

The fundamental challenge of aging and long-term survivorship is maintenance of functional independence and compression of morbidity despite a life history of disease. Inasmuch as immunity is a determinant of individual health and fitness, unraveling novel mechanisms of immune homeostasis in late life is of paramount interest. Comparative studies of young and old persons have documented age-related atrophy of the thymus, the contraction of diversity of the T cell receptor (TCR) repertoire, and the intrinsic inefficiency of classical TCR signaling in aged T cells. However, the elderly have highly heterogeneous health phenotypes. Studies of defined populations of persons aged 75 and older have led to the recognition of successful aging, a distinct physiologic construct characterized by high physical and cognitive functioning without measurable disability. Significantly, successful agers have a unique T cell repertoire; namely, the dominance of highly oligoclonal αβT cells expressing a diverse array of receptors normally expressed by NK cells. Despite their properties of cell senescence, these unusual NK-like T cells are functionally active effectors that do not require engagement of their clonotypic TCR. Thus, NK-like T cells represent a beneficial remodeling of the immune repertoire with advancing age, consistent with the concept of immune plasticity. Significantly, certain subsets are predictors of physical/cognitive performance among older adults. Further understanding of the roles of these NK-like T cells to host defense, and how they integrate with other physiologic domains of function are new frontiers for investigation in Aging Biology. Such pursuits will require a research paradigm shift from the usual young-versus-old comparison to the analysis of defined elderly populations. These endeavors may also pave way to age-appropriate, group-targeted immune interventions for the growing elderly population. PMID:27933066

Functionally Diverse NK-Like T Cells Are Effectors and Predictors of Successful Aging.

PubMed

Michel, Joshua J; Griffin, Patricia; Vallejo, Abbe N

2016-01-01

The fundamental challenge of aging and long-term survivorship is maintenance of functional independence and compression of morbidity despite a life history of disease. Inasmuch as immunity is a determinant of individual health and fitness, unraveling novel mechanisms of immune homeostasis in late life is of paramount interest. Comparative studies of young and old persons have documented age-related atrophy of the thymus, the contraction of diversity of the T cell receptor (TCR) repertoire, and the intrinsic inefficiency of classical TCR signaling in aged T cells. However, the elderly have highly heterogeneous health phenotypes. Studies of defined populations of persons aged 75 and older have led to the recognition of successful aging, a distinct physiologic construct characterized by high physical and cognitive functioning without measurable disability. Significantly, successful agers have a unique T cell repertoire; namely, the dominance of highly oligoclonal αβT cells expressing a diverse array of receptors normally expressed by NK cells. Despite their properties of cell senescence, these unusual NK-like T cells are functionally active effectors that do not require engagement of their clonotypic TCR. Thus, NK-like T cells represent a beneficial remodeling of the immune repertoire with advancing age, consistent with the concept of immune plasticity. Significantly, certain subsets are predictors of physical/cognitive performance among older adults. Further understanding of the roles of these NK-like T cells to host defense, and how they integrate with other physiologic domains of function are new frontiers for investigation in Aging Biology. Such pursuits will require a research paradigm shift from the usual young-versus-old comparison to the analysis of defined elderly populations. These endeavors may also pave way to age-appropriate, group-targeted immune interventions for the growing elderly population.

Polymorphonuclear neutrophils and granulocytic myeloid-derived suppressor cells inhibit natural killer cell activity toward Aspergillus fumigatus.

PubMed

Mueller-Leisse, Johanna; Brueggemann, Sabrina; Bouzani, Maria; Schmitt, Anna-Lena; Einsele, Hermann; Loeffler, Juergen

2015-08-01

Invasive aspergillosis is a devastating infectious disease in immunocompromised patients. Besides neutrophils and macrophages, natural killer (NK) cells have recently emerged as important players in immunity to this infection. It was shown that NK cells comprise an essential role in the clearance of Aspergillus fumigatus (A. fumigatus) in neutropenic but not in nonneutropenic mice. However, the antifungal activity of NK cells and their regulation have not been fully characterized. In this study, we investigated the interplay between polymorphonuclear neutrophils (PMNs) or granulocyte myeloid-derived suppressor cells (Gr-MDSCs) with NK cells. Both cell types exhibited an equal inhibitory effect on NK cell activation through downregulation of NKp30 expression on the cell surface and cytotoxicity towards the cell line K562. Furthermore, we showed that NK cell activation and antifungal cytotoxicity were impaired when NK cells had been cultured in the presence of PMNs or Gr-MDSCs before fungal stimulation. Besides the reduced cytotoxicity a decreased release of interferon gamma (IFNγ), a key player in the clearance of an A. fumigatus infection, was observed. Thus, inhibition of NK cell activity by PMNs or Gr-MDSCs might impair an effective anti-fungal immune response during recovery from conditions such as hematopoietic stem cell transplantation. © The Author 2015. Published by Oxford University Press on behalf of The International Society for Human and Animal Mycology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Non-CD34+ cells, especially CD8+ cytotoxic T cells and CD56+ natural killer cells, rather than CD34 cells, predict early engraftment and better transplantation outcomes in patients with hematologic malignancies after allogeneic peripheral stem cell transplantation.

PubMed

Kim, Dong Hwan; Won, Dong Il; Lee, Nan Young; Sohn, Sang Kyun; Suh, Jang Soo; Lee, Kyu Bo

2006-07-01

The effect of the transplant dose of each cell subset on engraftment kinetics and transplantation outcomes was evaluated in HLA-identical allogeneic peripheral blood stem cell transplantation (PBSCT). Sixty-nine patients were included in this retrospective study. Engraftment kinetics, transplantation outcomes, and immune reconstitution up to 1 year after transplantation were analyzed according to the transplant dose of CD34+ and non-CD34+ cells, including natural killer (NK) cells and CD8+ cytotoxic T (Tc) cells. An accelerated neutrophil engraftment was strongly associated with a higher transplant dose of NK cells (12 versus 16 days, P < .001) and Tc cells (13 versus 16 days, P < .001) but not CD34+ cells (P = .442). Survival analyses revealed a favorable prognosis for patients who received a higher dose of non-CD34+ cell subsets, rather than CD34+ cells, in terms of overall survival (OS; P = .024 for NK cells and .050 for Tc cells) and nonrelapse mortality (NRM; P = .005 for NK cells, .060 for Tc cells). In addition, a higher transplant dose of NK and Tc cells was correlated with a faster lymphoid reconstitution. In multivariate analyses, rapid neutrophil engraftment was correlated with a higher transplant dose of NK cells (P = .001) and Tc cells (P = .004). Moreover, an increased OS was associated with the NK cell dose (P = .007) and chronic graft-versus-host disease (P = .009), whereas a decreased NRM was associated with the NK dose (P = .024). In conclusion, in a PBSCT setting, a higher transplant dose of NK and Tc cells accelerated neutrophil engraftment, improved the immune reconstitution, and decreased NRM, thereby increasing OS after allogeneic PBSCT.

Evidence of functional cell-mediated immune responses to nontypeable Haemophilus influenzae in otitis-prone children

PubMed Central

Seppanen, Elke; Tan, Dino; Corscadden, Karli J.; Currie, Andrew J.; Richmond, Peter C.; Thornton, Ruth B.

2018-01-01

Otitis media (OM) remains a common paediatric disease, despite advances in vaccinology. Susceptibility to recurrent acute OM (rAOM) has been postulated to involve defective cell-mediated immune responses to common otopathogenic bacteria. We compared the composition of peripheral blood mononuclear cells (PBMC) from 20 children with a history of rAOM (otitis-prone) and 20 healthy non-otitis-prone controls, and assessed innate and cell-mediated immune responses to the major otopathogen nontypeable Haemophilus influenzae (NTHi). NTHi was a potent stimulator of inflammatory cytokine secretion from PBMC within 4 hours, with no difference in cytokine levels produced between PBMC from cases or controls. In the absence of antigen stimulation, otitis-prone children had more circulating Natural Killer (NK) cells (p<0.01), particularly NKdim (CD56lo) cells (p<0.01), but fewer CD4+ T cells (p<0.01) than healthy controls. NTHi challenge significantly increased the proportion of activated (CD107a+) NK cells in otitis-prone and non-otitis-prone children (p<0.01), suggesting that NK cells from otitis-prone children are functional and respond to NTHi. CD8+ T cells and NK cells from both cases and controls produced IFNγ in response to polyclonal stimulus (Staphylococcal enterotoxin B; SEB), with more IFNγ+ CD8+ T cells present in cases than controls (p<0.05) but similar proportions of IFNγ+ NK cells. Otitis-prone children had more circulating IFNγ-producing NK cells (p<0.05) and more IFNγ-producing CD4+ (p<0.01) or CD8+ T-cells (p<0.05) than healthy controls. In response to SEB, more CD107a-expressing CD8+ T cells were present in cases than controls (p<0.01). Despite differences in PBMC composition, PBMC from otitis-prone children mounted innate and T cell-mediated responses to NTHi challenge that were comparable to healthy children. These data provide evidence that otitis-prone children do not have impaired functional cell mediated immunity. PMID:29621281

Inhibition of histone H3K27 demethylases selectively modulates inflammatory phenotypes of natural killer cells.

PubMed

Cribbs, Adam; Hookway, Edward S; Wells, Graham; Lindow, Morten; Obad, Susanna; Oerum, Henrik; Prinjha, Rab K; Athanasou, Nick; Sowman, Aneka; Philpott, Martin; Penn, Henry; Soderstrom, Kalle; Feldmann, Marc; Oppermann, Udo

2018-02-16

Natural killer (NK) cells are innate lymphocytes, important in immune surveillance and elimination of stressed, transformed, or virus-infected cells. They critically shape the inflammatory cytokine environment to orchestrate interactions of cells of the innate and adaptive immune systems. Some studies have reported that NK cell activation and cytokine secretion are controlled epigenetically but have yielded only limited insight into the mechanisms. Using chemical screening with small-molecule inhibitors of chromatin methylation and acetylation, further validated by knockdown approaches, we here identified Jumonji-type histone H3K27 demethylases as key regulators of cytokine production in human NK cell subsets. The prototypic JMJD3/UTX (Jumonji domain-containing protein 3) H3K27 demethylase inhibitor GSK-J4 increased global levels of the repressive H3K27me3 mark around transcription start sites of effector cytokine genes. Moreover, GSK-J4 reduced IFN-γ, TNFα, granulocyte-macrophage colony-stimulating factor (GM-CSF), and interleukin-10 levels in cytokine-stimulated NK cells while sparing their cytotoxic killing activity against cancer cells. The anti-inflammatory effect of GSK-J4 in NK cell subsets, isolated from peripheral blood or tissue from individuals with rheumatoid arthritis (RA), coupled with an inhibitory effect on formation of bone-resorbing osteoclasts, suggested that histone demethylase inhibition has broad utility for modulating immune and inflammatory responses. Overall, our results indicate that H3K27me3 is a dynamic and important epigenetic modification during NK cell activation and that JMJD3/UTX-driven H3K27 demethylation is critical for NK cell function. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Location and cellular stages of NK cell development

PubMed Central

Yu, Jianhua; Freud, Aharon G.; Caligiuri, Michael A

2013-01-01

The identification of distinct tissue-specific natural killer (NK) cell populations that apparently mature from local precursor populations has brought new insight into the diversity and developmental regulation of this important lymphoid subset. NK cells provide a necessary link between the early (innate) and late (adaptive) immune responses to infection. Gaining a better understanding of the processes that govern NK cell development should allow us to better harness NK cell functions in multiple clinical settings as well as to gain further insight into how these cells undergo malignant transformation. In this review, we summarize recent advances in understanding sites and cellular stages of NK cell development in humans and mice. PMID:24055329

NK cells and their receptors in naive and rituximab-treated patients with anti-MAG polyneuropathy.

PubMed

Benedetti, Luana; Facco, Monica; Franciotta, Diego; Dalla Torre, Chiara; Campagnolo, Marta; Lucchetta, Marta; Boscaro, Elisa; Ermani, Mario; Del Sette, Massimo; Berno, Tamara; Candiotto, Laura; Zambello, Renato; Briani, Chiara

2013-08-15

Natural killer (NK) cells can bridge innate and acquired immunity, and play a role in autoimmunity. A few studies evaluated the distribution of NK cells and the expression of their receptors in chronic immune-mediated demyelinating polyneuropathies. We investigated NK cell distribution and NK cell receptor expression in 20 naïve patients with anti-MAG polyneuropathy (MAG-PN). Using flow cytometry, we analysed NK cells and a series of NK cell receptors in the peripheral blood of patients with MAG-PN, and, as controls, in patients with chronic inflammatory demyelinating peripheral polyradiculoneuropathy (CIDP) and in healthy subjects. Six MAG-PN patients were also tested after rituximab treatment. At baseline the percentage of NK cells did not differ among the groups. KIR2DL2 receptor expression in MAG-PN patients was higher, andCD94/NKG2A receptor expression in both MAG-PN and CIDP patients was lower than in healthy controls. These abnormalities did not correlate with any clinical or demographic variable. No modification was found after rituximab therapy. The data suggest that MAG-PN shows abnormalities in NK cell receptors that characterise other autoimmune diseases, and cannot help in differential diagnosis with CIDP. The impairment of the relevant CD94/NKG2A inhibitory pathway, which might play a central role in the development and perpetuation of MAG-PN, warrants further functional investigations. Copyright © 2013 Elsevier B.V. All rights reserved.

Critical role of dendritic cell-derived IL-27 in antitumor immunity through regulating the recruitment and activation of NK and NKT cells.

PubMed

Wei, Jun; Xia, Siyuan; Sun, Huayan; Zhang, Song; Wang, Jingya; Zhao, Huiyuan; Wu, Xiaoli; Chen, Xi; Hao, Jianlei; Zhou, Xinglong; Zhu, Zhengmao; Gao, Xiang; Gao, Jian-xin; Wang, Puyue; Wu, Zhenzhou; Zhao, Liqing; Yin, Zhinan

2013-07-01

Critical roles of IL-27 in autoimmune diseases and infections have been reported; however, the contribution of endogenous IL-27 to tumor progression remains elusive. In this study, by using IL-27p28 conditional knockout mice, we demonstrate that IL-27 is critical in protective immune response against methyl-cholanthrene-induced fibrosarcoma and transplanted B16 melanoma, and dendritic cells (DCs) are the primary source. DC-derived IL-27 is required for shaping tumor microenvironment by inducing CXCL-10 expression in myeloid-derived suppressor cells and regulating IL-12 production from DCs, which lead to the recruitment and activation of NK and NKT cells resulting in immunological control of tumors. Indeed, reconstitution of IL-27 or CXCL-10 in tumor site significantly inhibits tumor growth and restores the number and activation of NK and NKT cells. In summary, our study identifies a previous unknown critical role of DC-derived IL-27 in NK and NKT cell-dependent antitumor immunity through shaping tumor microenvironment, and sheds light on developing novel therapeutic approaches based on IL-27.

Interleukin (IL)-23 Stimulates IFN-γ Secretion by CD56bright Natural Killer Cells and Enhances IL-18-Driven Dendritic Cells Activation.

PubMed

Ziblat, Andrea; Nuñez, Sol Y; Raffo Iraolagoitia, Ximena Lucía; Spallanzani, Raúl German; Torres, Nicolás I; Sierra, Jessica M; Secchiari, Florencia; Domaica, Carolina I; Fuertes, Mercedes B; Zwirner, Norberto W

2017-01-01

Interleukin (IL)-23 is a member of the IL-12 family of cytokines that, as the other members of this family, is secreted by monocytes, macrophages, and dendritic cells (DC) upon recognition of bacterial, viral, and fungal components. IL-23 is critical during immunity against acute infections, and it is also involved in the development of autoimmune diseases. Although immunoregulatory effects of IL-23 on mouse natural killer (NK) cells have been described, the effect of IL-23 on human NK cells remains ill-defined. In this study, we observed that monocytes stimulated with LPS secreted IL-23 and that blockade of this cytokine during monocyte and NK cell coculture led to a diminished production of IFN-γ by NK cells. Accordingly, rIL-23-induced NK cell activation and stimulated IFN-γ production by CD56 bright NK cells. This effect involved MEK1/MEK2, JNK, PI3K, mammalian target of rapamycin, and NF-κB, but not STAT-1, STAT-3, nor p38 MAPK pathways. Moreover, while NK cell-mediated cytotoxicity remained unaltered, antibody-dependent cellular cytotoxicity (ADCC) was enhanced after IL-23 stimulation. In addition, IL-23 displayed a synergistic effect with IL-18 for IFN-γ production by both CD56 bright and CD56 dim NK cells, and this effect was due to a priming effect of IL-23 for IL-18 responsiveness. Furthermore, NK cells pre-stimulated with IL-18 promoted an increase in CD86 expression and IL-12 secretion by DC treated with LPS, and IL-23 potentiated these effects. Moreover, IL-23-driven enhancement of NK cell "helper" function was dependent on NK cell-derived IFN-γ. Therefore, our results suggest that IL-23 may trigger NK cell-mediated "helper" effects on adaptive immunity, shaping T cell responses during different pathological situations through the regulation of DC maturation.

Interleukin (IL)-23 Stimulates IFN-γ Secretion by CD56bright Natural Killer Cells and Enhances IL-18-Driven Dendritic Cells Activation

PubMed Central

Ziblat, Andrea; Nuñez, Sol Y.; Raffo Iraolagoitia, Ximena Lucía; Spallanzani, Raúl German; Torres, Nicolás I.; Sierra, Jessica M.; Secchiari, Florencia; Domaica, Carolina I.; Fuertes, Mercedes B.; Zwirner, Norberto W.

2018-01-01

Interleukin (IL)-23 is a member of the IL-12 family of cytokines that, as the other members of this family, is secreted by monocytes, macrophages, and dendritic cells (DC) upon recognition of bacterial, viral, and fungal components. IL-23 is critical during immunity against acute infections, and it is also involved in the development of autoimmune diseases. Although immunoregulatory effects of IL-23 on mouse natural killer (NK) cells have been described, the effect of IL-23 on human NK cells remains ill-defined. In this study, we observed that monocytes stimulated with LPS secreted IL-23 and that blockade of this cytokine during monocyte and NK cell coculture led to a diminished production of IFN-γ by NK cells. Accordingly, rIL-23-induced NK cell activation and stimulated IFN-γ production by CD56bright NK cells. This effect involved MEK1/MEK2, JNK, PI3K, mammalian target of rapamycin, and NF-κB, but not STAT-1, STAT-3, nor p38 MAPK pathways. Moreover, while NK cell-mediated cytotoxicity remained unaltered, antibody-dependent cellular cytotoxicity (ADCC) was enhanced after IL-23 stimulation. In addition, IL-23 displayed a synergistic effect with IL-18 for IFN-γ production by both CD56bright and CD56dim NK cells, and this effect was due to a priming effect of IL-23 for IL-18 responsiveness. Furthermore, NK cells pre-stimulated with IL-18 promoted an increase in CD86 expression and IL-12 secretion by DC treated with LPS, and IL-23 potentiated these effects. Moreover, IL-23-driven enhancement of NK cell “helper” function was dependent on NK cell-derived IFN-γ. Therefore, our results suggest that IL-23 may trigger NK cell-mediated “helper” effects on adaptive immunity, shaping T cell responses during different pathological situations through the regulation of DC maturation. PMID:29403472

Suppression of natural killer cell cytotoxicity in postpartum women: time course and potential mechanisms.

PubMed

Groer, Maureen W; El-Badri, Nagwa; Djeu, Julie; Williams, S Nicole; Kane, Bradley; Szekeres, Karoly

2014-07-01

Little is known about the recovery of the immune system from normal pregnancy and whether the postpartum period is a uniquely adapted immune state. This report extends previous observations from our group of decreased natural killer (NK) cell cytotoxicity in the postpartum period. NK cytotoxicity was measured from 1 week through 9 months postpartum. In addition, NK cytotoxicity was assayed in the presence or absence of pooled plasmas collected from either postpartum or nonpostpartum women. Samples of cells were stained for inhibitory receptors and analyzed by flow cytometry. NK cytotoxicity remained decreased in postpartum women compared to controls through the first 6 postpartum months, returned to normal levels by 9 months, and remained normal at 12 months. NK cytotoxicity during the first 6 months was further inhibited by the addition of pooled plasma to NK cultures from postpartum women, but the addition of pooled plasma from the control group did not affect that group's NK cultures. There were differences in inhibitory receptor staining between the two groups, with decreased CD158a and CD158b and increased NKG2A expression on postpartum NK cells during the first 3 postpartum months. These data suggest that NK cytotoxicity postpartum inhibition lasts 6 months and is influenced by unidentified postpartum plasma components. The effect may also involve receptors on NK cells. © The Author(s) 2013.

Cytomegalovirus immune evasion by perturbation of endosomal trafficking

PubMed Central

Lučin, Pero; Mahmutefendić, Hana; Blagojević Zagorac, Gordana; Ilić Tomaš, Maja

2015-01-01

Cytomegaloviruses (CMVs), members of the herpesvirus family, have evolved a variety of mechanisms to evade the immune response to survive in infected hosts and to establish latent infection. They effectively hide infected cells from the effector mechanisms of adaptive immunity by eliminating cellular proteins (major histocompatibility Class I and Class II molecules) from the cell surface that display viral antigens to CD8 and CD4 T lymphocytes. CMVs also successfully escape recognition and elimination of infected cells by natural killer (NK) cells, effector cells of innate immunity, either by mimicking NK cell inhibitory ligands or by downregulating NK cell-activating ligands. To accomplish these immunoevasion functions, CMVs encode several proteins that function in the biosynthetic pathway by inhibiting the assembly and trafficking of cellular proteins that participate in immune recognition and thereby, block their appearance at the cell surface. However, elimination of these proteins from the cell surface can also be achieved by perturbation of their endosomal route and subsequent relocation from the cell surface into intracellular compartments. Namely, the physiological route of every cellular protein, including immune recognition molecules, is characterized by specific features that determine its residence time at the cell surface. In this review, we summarize the current understanding of endocytic trafficking of immune recognition molecules and perturbations of the endosomal system during infection with CMVs and other members of the herpesvirus family that contribute to their immune evasion mechanisms. PMID:25263490

HLA-E upregulation on IFN-gamma-activated AML blasts impairs CD94/NKG2A-dependent NK cytolysis after haplo-mismatched hematopoietic SCT.

PubMed

Nguyen, S; Beziat, V; Dhedin, N; Kuentz, M; Vernant, J P; Debre, P; Vieillard, V

2009-05-01

Natural killer (NK) cells generated after haploidentical hematopoietic SCT in patients with AML are characterized by specific phenotypic features and impaired functioning that may affect transplantation outcome. We show that IFN-gamma produced by immature CD56(bright) NK cells upregulates cell surface expression of HLA-E on AML blasts and that this upregulation protects leukemic cells from NK-mediated cell lysis through the mediation of CD94/NKG2A, an inhibitory receptor overexpressed on NK cells after haploidentical SCT. Two years after transplantation, however, maturing NK cells were functionally active, as evidenced by high cytotoxicity and poor IFN-gamma production. This implies that maturation of NK cells is the key to improved immune responses and transplantation outcome.

Interplay between Natural Killer Cells and Anti-HER2 Antibodies: Perspectives for Breast Cancer Immunotherapy

PubMed Central

Muntasell, Aura; Cabo, Mariona; Servitja, Sonia; Tusquets, Ignasi; Martínez-García, María; Rovira, Ana; Rojo, Federico; Albanell, Joan; López-Botet, Miguel

2017-01-01

Overexpression of the human epidermal growth factor receptor 2 (HER2) defines a subgroup of breast tumors with aggressive behavior. The addition of HER2-targeted antibodies (i.e., trastuzumab, pertuzumab) to chemotherapy significantly improves relapse-free and overall survival in patients with early-stage and advanced disease. Nonetheless, considerable proportions of patients develop resistance to treatment, highlighting the need for additional and co-adjuvant therapeutic strategies. HER2-specific antibodies can trigger natural killer (NK) cell-mediated antibody-dependent cellular cytotoxicity and indirectly enhance the development of tumor-specific T cell immunity; both mechanisms contributing to their antitumor efficacy in preclinical models. Antibody-dependent NK cell activation results in the release of cytotoxic granules as well as the secretion of pro-inflammatory cytokines (i.e., IFNγ and TNFα) and chemokines. Hence, NK cell tumor suppressive functions include direct cytolytic killing of tumor cells as well as the regulation of subsequent antitumor adaptive immunity. Albeit tumors with gene expression signatures associated to the presence of cytotoxic lymphocyte infiltrates benefit from trastuzumab-based treatment, NK cell-related biomarkers of response/resistance to HER2-specific therapeutic antibodies in breast cancer patients remain elusive. Several variables, including (i) the configuration of the patient NK cell repertoire; (ii) tumor molecular features (i.e., estrogen receptor expression); (iii) concomitant therapeutic regimens (i.e., chemotherapeutic agents, tyrosine kinase inhibitors); and (iv) evasion mechanisms developed by progressive breast tumors, have been shown to quantitatively and qualitatively influence antibody-triggered NK cell responses. In this review, we discuss possible interventions for restoring/enhancing the therapeutic activity of HER2 therapeutic antibodies by harnessing NK cell antitumor potential through combinatorial approaches, including immune checkpoint blocking/stimulatory antibodies, cytokines and toll-like receptor agonists. PMID:29181007

NK cell-based immunotherapy for malignant diseases

PubMed Central

Cheng, Min; Chen, Yongyan; Xiao, Weihua; Sun, Rui; Tian, Zhigang

2013-01-01

Natural killer (NK) cells play critical roles in host immunity against cancer. In response, cancers develop mechanisms to escape NK cell attack or induce defective NK cells. Current NK cell-based cancer immunotherapy aims to overcome NK cell paralysis using several approaches. One approach uses expanded allogeneic NK cells, which are not inhibited by self histocompatibility antigens like autologous NK cells, for adoptive cellular immunotherapy. Another adoptive transfer approach uses stable allogeneic NK cell lines, which is more practical for quality control and large-scale production. A third approach is genetic modification of fresh NK cells or NK cell lines to highly express cytokines, Fc receptors and/or chimeric tumor-antigen receptors. Therapeutic NK cells can be derived from various sources, including peripheral or cord blood cells, stem cells or even induced pluripotent stem cells (iPSCs), and a variety of stimulators can be used for large-scale production in laboratories or good manufacturing practice (GMP) facilities, including soluble growth factors, immobilized molecules or antibodies, and other cellular activators. A list of NK cell therapies to treat several types of cancer in clinical trials is reviewed here. Several different approaches to NK-based immunotherapy, such as tissue-specific NK cells, killer receptor-oriented NK cells and chemically treated NK cells, are discussed. A few new techniques or strategies to monitor NK cell therapy by non-invasive imaging, predetermine the efficiency of NK cell therapy by in vivo experiments and evaluate NK cell therapy approaches in clinical trials are also introduced. PMID:23604045

The Broad Spectrum of Human Natural Killer Cell Diversity.

PubMed

Freud, Aharon G; Mundy-Bosse, Bethany L; Yu, Jianhua; Caligiuri, Michael A

2017-11-21

Natural killer (NK) cells provide protection against infectious pathogens and cancer. For decades it has been appreciated that two major NK cell subsets (CD56 bright and CD56 dim ) exist in humans and have distinct anatomical localization patterns, phenotypes, and functions in immunity. In light of this traditional NK cell dichotomy, it is now clear that the spectrum of human NK cell diversity is much broader than originally appreciated as a result of variegated surface receptor, intracellular signaling molecule, and transcription factor expression; tissue-specific imprinting; and foreign antigen exposure. The recent discoveries of tissue-resident NK cell developmental intermediates, non-NK innate lymphoid cells, and the capacity for NK cells to adapt and differentiate into long-lived memory cells has added further complexity to this field. Here we review our current understanding of the breadth and generation of human NK cell diversity. Copyright © 2017 Elsevier Inc. All rights reserved.

Boosting Natural Killer Cell-Based Immunotherapy with Anticancer Drugs: a Perspective.

PubMed

Cifaldi, Loredana; Locatelli, Franco; Marasco, Emiliano; Moretta, Lorenzo; Pistoia, Vito

2017-12-01

Natural killer (NK) cells efficiently recognize and kill tumor cells through several mechanisms including the expression of ligands for NK cell-activating receptors on target cells. Different clinical trials indicate that NK cell-based immunotherapy represents a promising antitumor treatment. However, tumors develop immune-evasion strategies, including downregulation of ligands for NK cell-activating receptors, that can negatively affect antitumor activity of NK cells, which either reside endogenously, or are adoptively transferred. Thus, restoration of the expression of NK cell-activating ligands on tumor cells represents a strategic therapeutic goal. As discussed here, various anticancer drugs can fulfill this task via different mechanisms. We envision that the combination of selected chemotherapeutic agents with NK cell adoptive transfer may represent a novel strategy for cancer immunotherapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Activation of cellular immunity and marked inhibition of liver cancer in a mouse model following gene therapy and tumor expression of GM-SCF, IL-21, and Rae-1.

PubMed

Cheng, Mingrong; Zhi, Kangkang; Gao, Xiaoyan; He, Bing; Li, Yingchun; Han, Jiang; Zhang, Zhiping; Wu, Yan

2013-12-18

Cancer is both a systemic and a genetic disease. The pathogenesis of cancer might be related to dampened immunity. Host immunity recognizes nascent malignant cells - a process referred to as immune surveillance. Augmenting immune surveillance and suppressing immune escape are crucial in tumor immunotherapy. A recombinant plasmid capable of co-expressing granulocyte-macrophage colony- stimulating factor (GM-SCF), interleukin-21 (IL-21), and retinoic acid early transcription factor-1 (Rae-1) was constructed, and its effects determined in a mouse model of subcutaneous liver cancer. Serum specimens were assayed for IL-2 and INF-γ by ELISA. Liver cancer specimens were isolated for Rae-1 expression by RT-PCR and Western blot, and splenocytes were analyzed by flow cytometry. The recombinant plasmid inhibited the growth of liver cancer and prolonged survival of tumor-loaded mice. Activation of host immunity might have contributed to this effect by promoting increased numbers and cytotoxicity of natural killer (NK) cells and cytotoxic T lymphocytes (CTL) following expression of GM-SCF, IL-21, and Rae-1. By contrast, the frequency of regulatory T cells was decreased, Consequently, activated CTL and NK cells enhanced their secretion of INF-γ, which promoted cytotoxicity of NK cells and CTL. Moreover, active CTL showed dramatic secretion of IL-2, which stimulates CTL. The recombinant expression plasmid also augmented Rae-1 expression by liver cancer cells. Rae-1 receptor expressing CTL and NK cells removed liver cancer. The recombinant expression plasmid inhibited liver cancer by a mechanism that involved activation of cell-mediated immunity and Rae-1 in liver cancer.

Innate Lymphoid Cells in Tumor Immunity.

PubMed

van Beek, Jasper J P; Martens, Anne W J; Bakdash, Ghaith; de Vries, I Jolanda M

2016-02-25

Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring.

Innate Lymphoid Cells in Tumor Immunity

PubMed Central

van Beek, Jasper J. P.; Martens, Anne W. J.; Bakdash, Ghaith; de Vries, I. Jolanda M.

2016-01-01

Innate lymphoid cells (ILCs) are a group of immune cells of the lymphoid lineage that do not possess antigen specificity. The group includes natural killer (NK) cells, lymphoid tissue inducer (LTi) cells and the recently identified ILC1s, ILC2s and ILC3s. Although the role of NK cells in the context of cancer has been well established, the involvement of other ILC subsets in cancer progression and resistance is just emerging. Here, we review the literature on the role of the different ILC subsets in tumor immunity and discuss its implications for cancer treatment and monitoring. PMID:28536374

Natural Killer Cells in Obesity: Impaired Function and Increased Susceptibility to the Effects of Cigarette Smoke

PubMed Central

O'Shea, Donal; Cawood, Tom J.; O'Farrelly, Cliona; Lynch, Lydia

2010-01-01

Background Obese individuals who smoke have a 14 year reduction in life expectancy. Both obesity and smoking are independantly associated with increased risk of malignancy. Natural killer cells (NK) are critical mediators of anti-tumour immunity and are compromised in obese patients and smokers. We examined whether NK cell function was differentially affected by cigarette smoke in obese and lean subjects. Methodology and Principal Findings Clinical data and blood were collected from 40 severely obese subjects (BMI>40 kg/m2) and 20 lean healthy subjects. NK cell levels and function were assessed using flow cytometry and cytotoxicity assays. The effect of cigarette smoke on NK cell ability to kill K562 tumour cells was assessed in the presence or absence of the adipokines leptin and adiponectin. NK cell levels were significantly decreased in obese subjects compared to lean controls (7.6 vs 16.6%, p = 0.0008). NK function was also significantly compromised in obese patients (30% +/− 13% vs 42% +/−12%, p = 0.04). Cigarette smoke inhibited NK cell ability to kill tumour cell lines (p<0.0001). NK cells from obese subjects were even more susceptible to the inhibitory effects of smoke compared to lean subjects (33% vs 28%, p = 0.01). Cigarette smoke prevented NK cell activation, as well as perforin and interferon-gamma secretion upon tumour challenge. Adiponectin but not leptin partially reversed the effects of smoke on NK cell function in both obese (p = 0.002) and lean controls (p = 0.01). Conclusions/Significance Obese subjects have impaired NK cell activity that is more susceptible to the detrimental effects of cigarette smoke compared to lean subjects. This may play a role in the increase of cancer and infection seen in this population. Adiponectin is capable of restoring NK cell activity and may have therapeutic potential for immunity in obese subjects and smokers. PMID:20107494

The PD-1/B7-H1 pathway modulates the natural killer cells versus mouse glioma stem cells.

PubMed

Huang, Bo Yuan; Zhan, Yi Ping; Zong, Wen Jing; Yu, Chun Jiang; Li, Jun Fa; Qu, Yan Ming; Han, Song

2015-01-01

Glioblastoma multiforme (GBM) is the most malignant primary type of brain tumor in adults. There has been increased focus on the immunotherapies to treat GBM patients, the therapeutic value of natural killer (NK) cells is still unknown. Programmed death-1 (PD-1) is a major immunological checkpoint that can negatively regulate the T-cell-mediated immune response. We tested the combination of the inhibiting the PD-1/B7H1 pathway with a NK-cell mediated immune response in an orthotopic mouse model of GBM. Mouse glioma stem cells (GL261GSCs) and mouse NK cells were isolated and identified. A lactate dehydrogenase (LDH) assay was perfomed to detect the cytotoxicity of NK cells against GL261GSCs. GL261GSCs were intracranially implanted into mice, and the mice were stratified into 3 treatment groups: 1) control, 2) NK cells treatment, and 3) PD-1 inhibited NK cells treatment group. Overall survival was quantified, and animal magnetic resonance imaging (MRI) was performed to determine tumor growth. The brains were harvested after the mice were euthanized, and immunohistochemistry against CD45 and PCNA was performed. The mouse NK cells were identified as 90% CD3- NK1.1+CD335+ by flow cytometric analysis. In the LDH assay, the ratios of the damaged GL261GSCs, with the E:T ratios of 2.5:1, 5:1, and 10:1, were as follows: 1) non-inhibited group: 7.42%, 11.31%, and 15.1%, 2) B7H1 inhibited group: 14.75%, 18.25% and 29.1%, 3) PD-1 inhibited group: 15.53%, 19.21% and 29.93%, 4) double inhibited group: 33.24%, 42.86% and 54.91%. In the in vivo experiments, the mice in the PD-1 inhibited NK cells treatment group and IL-2-stimulated-NK cells treatment group displayed a slowest tumor growth (F = 308.5, P<0.01) and a slower tumor growth compared with control group (F = 118.9, P<0.01), respectively. The median survival of the mice in the three groups were as follows: 1) conrol group: 29 days, 2) NK cells treatment group: 35 days (P = 0.0012), 3) PD-1 inhibited NK cells treatment group: 44 days (P = 0.0024). Immunologic data of PCNA-positive cell ratios and CD45-positive cell ratios of the tumor specimens in the three groups were as follows: 1) control group: 65.72% (PCNA) and 0.92% (CD45), 2) NK treatment group: 27.66% (PCNA) and 13.46% (CD45), and 3) PD-1 inhibited NK cells treatment group: 13.66% (PCNA) and 23.66% (CD45) (P<0.001). The results demonstrated that blockade of PD-1/B7H1 pathway could promote mouse NK cells to kill the GL261GSCs, and the PD-1-inhibited NK cells could be a feasible immune therapeutic approach against GBM.

Acute virus control mediated by licensed NK cells sets primary CD8+ T cell dependence on CD27 costimulation1,2,3

PubMed Central

Teoh, Jeffrey J.; Gamache, Awndre E.; Gillespie, Alyssa L.; Stadnisky, Michael D.; Yagita, Hideo; Bullock, Timothy N.J.; Brown, Michael G.

2016-01-01

Natural killer (NK) cells represent a critical first-line of immune defense against a bevy of viral pathogens, and infection can provoke them to mediate both supportive and suppressive effects on virus-specific adaptive immunity. In mice expressing MHC I Dk, a major MCMV resistance factor and self-ligand of the inhibitory Ly49G2 (G2) receptor, licensed G2+ NK cells provide essential host resistance against murine (M)CMV infection. Additionally G2+ NK cell responses to MCMV increase the rate and extent of dendritic cell (DC) recovery, as well as early priming of CD8+ T-cell effectors in response to MCMV. However, relatively little is known about the NK-cell effect on co-stimulatory ligand patterns displayed by DCs, or ensuing effector and memory T-cell responses. Here we found that CD27-dependent CD8+ T-cell priming and differentiation is shaped by the efficiency of NK responses to virus infection. Surprisingly, differences in specific NK responses to MCMV in Dk-disparate mice failed to distinguish early DC co-stimulatory patterns. Nonetheless, while CD27 deficiency did not impede licensed NK-mediated resistance, both CD70 and CD27 were required to efficiently prime and regulate effector CD8+ T-cell differentiation in response to MCMV, which eventually resulted in biased memory T-cell precursor formation in Dk mice. In contrast, CD8+ T-cells accrued more slowly in non-Dk mice, and eventually differentiated into terminal effector cells regardless of CD27 stimulation. Disparity in this requirement for CD27 signaling indicates that specific virus control mediated by NK cells can shape DC co-stimulatory signals needed to prime CD8+ T cells and eventual T-cell fate decisions. PMID:27798162

VSVΔG/EBOV GP-induced innate protection enhances natural killer cell activity to increase survival in a lethal mouse adapted Ebola virus infection.

PubMed

Williams, Kinola J N; Qiu, Xiangguo; Fernando, Lisa; Jones, Steven M; Alimonti, Judie B

2015-02-01

Members of the species Zaire ebolavirus cause severe hemorrhagic fever with up to a 90% mortality rate in humans. The VSVΔG/EBOV GP vaccine has provided 100% protection in the mouse, guinea pig, and nonhuman primate (NHP) models, and has also been utilized as a post-exposure therapeutic to protect mice, guinea pigs, and NHPs from a lethal challenge of Ebola virus (EBOV). EBOV infection causes rapid mortality in human and animal models, with death occurring as early as 6 days after infection, suggesting a vital role for the innate immune system to control the infection before cells of the adaptive immune system can assume control. Natural killer (NK) cells are the predominant cell of the innate immune response, which has been shown to expand with VSVΔG/EBOV GP treatment. In the current study, an in vivo mouse model of the VSVΔG/EBOV GP post-exposure treatment was used for a mouse adapted (MA)-EBOV infection, to determine the putative VSVΔG/EBOV GP-induced protective mechanism of NK cells. NK depletion studies demonstrated that mice with NK cells survive longer in a MA-EBOV infection, which is further enhanced with VSVΔG/EBOV GP treatment. NK cell mediated cytotoxicity and IFN-γ secretion was significantly higher with VSVΔG/EBOV GP treatment. Cell mediated cytotoxicity assays and perforin knockout mice experiments suggest that there are perforin-dependent and -independent mechanisms involved. Together, these data suggest that NK cells play an important role in VSVΔG/EBOV GP-induced protection of EBOV by increasing NK cytotoxicity, and IFN-γ secretion.

Diet-induced obesity, exogenous leptin-, and MADB106 tumor cell challenge affect tissue leukocyte distribution and serum levels of cytokines in F344 rats.

PubMed

Behrendt, Patrick; Buchenauer, Tobias; Horn, Rüdiger; Brabant, Georg; Jacobs, Roland; Bode, Felix; Stephan, Michael; Nave, Heike

2010-08-01

The adipocyte-derived catabolic protein leptin alters cell-mediated immunity and cytokine crosstalk. This may provide new insights into the altered immune response, seen in obese individuals. Therefore, we determined the tissue distribution of immune cells in diet-induced obese (dio) and normal weight F344 rats challenged with MADB106 tumor cells or leptin. Immune cell distribution in blood (by FACS analysis) and tissues (NK cells in spleen and liver, immunohistologically) as well as pro-inflammatory cytokines (IL-6, TNF-α; by flow cytometry) were investigated in 28 normal weight and 28 dio rats (n = 4-6/group). Pro-inflammatory cytokines were increased 3-fold for IL-6 and 7-fold for TNF-α in obese animals. Higher numbers of blood monocytes and NK cells were found in obese as compared to normal weight animals. In dio rats challenged with leptin and MADB106 tumor cells, monocyte numbers were decreased as compared to the obese control animals. Immunohistochemistry revealed an altered NK cell distribution in a compartment-, treatment-, and bodyweight-specific manner. In conclusion, our data reveal a distinct distribution pattern of monocytes and NK cells in dio rats as compared to normal weight littermates and an additional modulatory effect of a leptin- and MADB106 tumor cell challenge.

Role of natural killer cells in innate protection against lethal ebola virus infection.

PubMed

Warfield, Kelly L; Perkins, Jeremy G; Swenson, Dana L; Deal, Emily M; Bosio, Catharine M; Aman, M Javad; Yokoyama, Wayne M; Young, Howard A; Bavari, Sina

2004-07-19

Ebola virus is a highly lethal human pathogen and is rapidly driving many wild primate populations toward extinction. Several lines of evidence suggest that innate, nonspecific host factors are potentially critical for survival after Ebola virus infection. Here, we show that nonreplicating Ebola virus-like particles (VLPs), containing the glycoprotein (GP) and matrix protein virus protein (VP)40, administered 1-3 d before Ebola virus infection rapidly induced protective immunity. VLP injection enhanced the numbers of natural killer (NK) cells in lymphoid tissues. In contrast to live Ebola virus, VLP treatment of NK cells enhanced cytokine secretion and cytolytic activity against NK-sensitive targets. Unlike wild-type mice, treatment of NK-deficient or -depleted mice with VLPs had no protective effect against Ebola virus infection and NK cells treated with VLPs protected against Ebola virus infection when adoptively transferred to naive mice. The mechanism of NK cell-mediated protection clearly depended on perforin, but not interferon-gamma secretion. Particles containing only VP40 were sufficient to induce NK cell responses and provide protection from infection in the absence of the viral GP. These findings revealed a decisive role for NK cells during lethal Ebola virus infection. This work should open new doors for better understanding of Ebola virus pathogenesis and direct the development of immunotherapeutics, which target the innate immune system, for treatment of Ebola virus infection.

Optimal culture conditions for the generation of natural killer cell-induced dendritic cells for cancer immunotherapy.

PubMed

Nguyen-Pham, Thanh-Nhan; Yang, Deok-Hwan; Nguyen, Truc-Anh Thi; Lim, Mi-Seon; Hong, Cheol Yi; Kim, Mi-Hyun; Lee, Hyun Ju; Lee, Youn-Kyung; Cho, Duck; Bae, Soo-Young; Ahn, Jae-Sook; Kim, Yeo-Kyeoung; Chung, Ik-Joo; Kim, Hyeoung-Joon; Lee, Je-Jung

2012-01-01

Dendritic cell (DC)-based vaccines continue to be considered an attractive tool for cancer immunotherapy. DCs require an additional signal from the environment or other immune cells to polarize the development of immune responses toward T helper 1 (Th1) or Th2 responses. DCs play a role in natural killer (NK) cell activation, and NK cells are also able to activate and induce the maturation of DCs. We investigated the types of NK cells that can induce the maturation and enhanced function of DCs and the conditions under which these interactions occur. DCs that were activated by resting NK cells in the presence of inflammatory cytokines exhibited increased expression of several costimulatory molecules and an enhanced ability to produce IL-12p70. NK cell-stimulated DCs potently induced Th1 polarization and exhibited the ability to generate tumor antigen-specific cytotoxic T lymphocyte responses. Our data demonstrate that functional DCs can be generated by coculturing immature DCs with freshly isolated resting NK cells in the presence of Toll-like receptor agonists and proinflammatory cytokines and that the resulting DCs effectively present antigens to induce tumor-specific T-cell responses, which suggests that these cells may be useful for cancer immunotherapy.

Respiratory Influenza A Virus Infection Triggers Local and Systemic Natural Killer Cell Activation via Toll-Like Receptor 7.

PubMed

Stegemann-Koniszewski, Sabine; Behrens, Sarah; Boehme, Julia D; Hochnadel, Inga; Riese, Peggy; Guzmán, Carlos A; Kröger, Andrea; Schreiber, Jens; Gunzer, Matthias; Bruder, Dunja

2018-01-01

The innate immune system senses influenza A virus (IAV) through different pathogen-recognition receptors including Toll-like receptor 7 (TLR7). Downstream of viral recognition natural killer (NK) cells are activated as part of the anti-IAV immune response. Despite the known decisive role of TLR7 for NK cell activation by therapeutic immunostimulatory RNAs, the contribution of TLR7 to the NK cell response following IAV infection has not been addressed. We have analyzed lung cytokine responses as well as the activation, interferon (IFN)-γ production, and cytotoxicity of lung and splenic NK cells following sublethal respiratory IAV infection in wild-type and TLR7ko mice. Early airway IFN-γ levels as well as the induction of lung NK cell CD69 expression and IFN-γ production in response to IAV infection were significantly attenuated in TLR7-deficient hosts. Strikingly, respiratory IAV infection also primed splenic NK cells for IFN-γ production, degranulation, and target cell lysis, all of which were fully dependent on TLR7. At the same time, lung type I IFN levels were significantly reduced in TLR7ko mice early following IAV infection, displaying a potential upstream mechanism of the attenuated NK cell activation observed. Taken together, our data clearly demonstrate a specific role for TLR7 signaling in local and systemic NK cell activation following respiratory IAV infection despite the presence of redundant innate IAV-recognition pathways.

Respiratory Influenza A Virus Infection Triggers Local and Systemic Natural Killer Cell Activation via Toll-Like Receptor 7

PubMed Central

Stegemann-Koniszewski, Sabine; Behrens, Sarah; Boehme, Julia D.; Hochnadel, Inga; Riese, Peggy; Guzmán, Carlos A.; Kröger, Andrea; Schreiber, Jens; Gunzer, Matthias; Bruder, Dunja

2018-01-01

The innate immune system senses influenza A virus (IAV) through different pathogen-recognition receptors including Toll-like receptor 7 (TLR7). Downstream of viral recognition natural killer (NK) cells are activated as part of the anti-IAV immune response. Despite the known decisive role of TLR7 for NK cell activation by therapeutic immunostimulatory RNAs, the contribution of TLR7 to the NK cell response following IAV infection has not been addressed. We have analyzed lung cytokine responses as well as the activation, interferon (IFN)-γ production, and cytotoxicity of lung and splenic NK cells following sublethal respiratory IAV infection in wild-type and TLR7ko mice. Early airway IFN-γ levels as well as the induction of lung NK cell CD69 expression and IFN-γ production in response to IAV infection were significantly attenuated in TLR7-deficient hosts. Strikingly, respiratory IAV infection also primed splenic NK cells for IFN-γ production, degranulation, and target cell lysis, all of which were fully dependent on TLR7. At the same time, lung type I IFN levels were significantly reduced in TLR7ko mice early following IAV infection, displaying a potential upstream mechanism of the attenuated NK cell activation observed. Taken together, our data clearly demonstrate a specific role for TLR7 signaling in local and systemic NK cell activation following respiratory IAV infection despite the presence of redundant innate IAV-recognition pathways. PMID:29497422

HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells.

PubMed

Saïdi, Héla; Bras, Marlène; Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

2016-02-01

Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell-cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN-α-mediated TRAIL expression at the surface of pDCs and NK cells, and they suggest a novel mechanism of innate control of HIV-1 infection.

A Critical Role for the TLR4/TRIF Pathway in Allogeneic Hematopoietic Cell Rejection by Innate Immune Cells

PubMed Central

Xu, Hong; Yan, Jun; Zhu, Ziqiang; Hussain, Lala-Rukh; Huang, Yiming; Ding, Chuanlin; Bozulic, Larry D.; Wen, Yujie; Ildstad, Suzanne T.

2013-01-01

We show for the first time that signaling through the TLR4/TRIF pathway plays a critical role in allogeneic bone marrow cell (BMC) rejection. This appears to be unique to BMC as organ allografts are rejected mainly via MyD88 signaling. Using T or T/B cell-deficient mice, we found that BMC allorejection occurred early before T cell activation and was T and B cell-independent, suggesting an effector role for innate immune cells in BMC rejection. We further demonstrated the innate immune signaling in BMC allorejection by showing superior engraftment in mice deficient in TRIF or TLR4 but not MyD88 or TLR3. The restored cytotoxicity in TRIF deficient recipients transferred with wildtype F4/80+ or NK1.1+ cells suggests TRIF signaling dependence on macrophages or NK cells in early BMC rejection. Production of the proinflammatory cytokine IL-6 and TRIF relevant chemokine MCP-1 was significantly increased early after bone marrow transplantation. In vivo specific depletion of macrophages or NK innate immune cells in combination with anti-CD154/rapamycin resulted in additive-enhanced allogeneic engraftment. The requirement for irradiation was completely eliminated when both macrophages and NK cells were depleted in combination with anti-CD154/rapamycin to target T and B cells, supporting the hypothesis that two barriers involving innate and adaptive immunity exist in mediating rejection of allogeneic BMC. In summary, our results clearly demonstrate a previously unappreciated role for innate immunity in BMC allorejection via signaling through a unique MyD88-independent TLR4/TRIF mechanism. These findings may have direct clinical impact on strategies for conditioning recipients for stem cell transplantation. PMID:23146386

Hypoxic tumor-derived microvesicles negatively regulate NK cell function by a mechanism involving TGF-β and miR23a transfer.

PubMed

Berchem, Guy; Noman, Muhammad Zaeem; Bosseler, Manon; Paggetti, Jerome; Baconnais, Sonia; Le Cam, Eric; Nanbakhsh, Arash; Moussay, Etienne; Mami-Chouaib, Fathia; Janji, Bassam; Chouaib, Salem

2016-04-01

Tumor-derived microvesicles (TD-MVs) are key mediators which are shed by cancer cells and can sensitize neighboring cells in the tumor microenvironment. TD-MVs are extracellular vesicles composed of exosomes and MVs and promote cancer invasion and metastasis. Intratumoral hypoxia is an integral component of all solid tumors. The relationship between hypoxic tumor-shed MVs and NK-mediated cytotoxicity remains unknown. In this paper, we reported that MVs derived from hypoxic tumor cells qualitatively differ from those derived from normoxic tumor cells. Using multiple tumor models, we showed that hypoxic MVs inhibit more NK cell function as compared to normoxic MVs. Hypoxic TD-MVs package two immunosuppressive factors involved in the impairment of natural killer (NK) cell cytotoxicity against different tumor cells in vitro and in vivo . We showed that following their uptake by NK cells, hypoxic TD-MVs transfer TGF-β1 to NK cells, decreasing the cell surface expression of the activating receptor NKG2D, thereby inhibiting NK cell function. MicroRNA profiling revealed the presence of high levels of miR-210 and miR-23a in hypoxic TD-MVs. We demonstrated that miR-23a in hypoxic TD-MVs operates as an additional immunomosuppressive factor, since it directly targets the expression of CD107a in NK cells. To our knowledge, this is the first study to show that hypoxic tumor cells by secreting MVs can educate NK cells and decrease their antitumor immune response. This study highlights the existence of a novel mechanism of immune suppression mediated by hypoxic TD-MVs and further improves our understanding of the immunosuppressive mechanisms prevailing in the hypoxic tumor microenvironment.

Influence of physical activity on the immune system in breast cancer patients during chemotherapy.

PubMed

Schmidt, Thorsten; Jonat, Walter; Wesch, Daniela; Oberg, Hans-Heinrich; Adam-Klages, Sabine; Keller, Lisa; Röcken, Christoph; Mundhenke, Christoph

2018-03-01

Physical activity can impact the immune system in different ways, e.g. by alteration of the humoral and cellular immune response. Physical activity at medium intensity enhances numbers of cytotoxic T cells, NK cells and macrophages in healthy people. The aim of this study was to compare the effects of endurance and resistance training on the immune system in breast cancer patients during adjuvant chemotherapy. In a prospective, controlled and randomized intervention exploratory trial, 12-week supervised endurance or resistance training were compared with usual care twice a week. Endpoints were the absolute numbers of the immune cells such as CD3 + T lymphocytes including CD4 + - and CD8 + , αβ T cells, γδT cells, CD3 - /CD16 + /56 + NK cells and CD19 + B cells, before and after 12 weeks of treatment. Cell numbers were analyzed using fluorescence-activated cell sorting. Despite different physical interventions in all groups immune cell count decreased in CD3 T cells including TCR αβ and CD4 T cells, NK cells and CD19 B cells 12 weeks after initiation of chemotherapy and start of the physical intervention program, while the reduction of γδ T cells and CD8 T cells is less prominent in the RT and UC group. Chemotherapy led to a decrease in nearly all measured immune cells. In this study, physical intervention with endurance or resistance training did not suppress cellular immunity any further. Larger multicenter trials are needed to evaluate the exact impact of sports intervention on immune cell subpopulations.

CD11c identifies a subset of murine liver natural killer cells that responds to adenoviral hepatitis

PubMed Central

Burt, Bryan M.; Plitas, George; Stableford, Jennifer A.; Nguyen, Hoang M.; Bamboat, Zubin M.; Pillarisetty, Venu G.; DeMatteo, Ronald P.

2008-01-01

The liver contains a unique repertoire of immune cells and a particular abundance of NK cells. We have found that CD11c defines a distinct subset of NK cells (NK1.1+CD3−) in the murine liver whose function was currently unknown. In naïve animals, CD11c+ liver NK cells displayed an activated phenotype and possessed enhanced effector functions when compared with CD11c− liver NK cells. During the innate response to adenovirus infection, CD11c+ NK cells were the more common IFN-γ-producing NK cells in the liver, demonstrated enhanced lytic capability, and gained a modest degree of APC function. The mechanism of IFN-γ production in vivo depended on TLR9 ligation as well as IL-12 and -18. Taken together, our findings demonstrate that CD11c+ NK cells are a unique subset of NK cells in the murine liver that contribute to the defense against adenoviral hepatitis. PMID:18664530

Trichostatin A Sensitizes Hepatocellular Carcinoma Cells to Enhanced NK Cell-mediated Killing by Regulating Immune-related Genes.

PubMed

Shin, Sangsu; Kim, Miok; Lee, Seon-Jin; Park, Kang-Seo; Lee, Chang Hoon

2017-01-01

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. The ability of HCC to avoid immune detection is considered one of the main factors making it difficult to cure. Abnormal histone deacetylation is thought to be one of the mechanisms for HCC immune escape, making histone deacetylases (HDACs) attractive targets for HCC treatment. Here, we investigated the effect of trichostatin A (TSA), a highly potent HDAC inhibitor, on HCC (HepG2) gene expression and function. A genome wide-transcriptional microarray was used to identify genes regulated by TSA in HepG2 cells. Gene Ontology was used to identify pathways regulated by TSA, and these changes were confirmed by qPCR. The effect of TSA on natural killer (NK) cell-mediated killing of HCC cell lines were analyzed by both flow cytometry and LDH cytotoxicity assay. A study was also conducted in a Balb/c nude mice xenograft model to assess the anti-tumor activity of TSA. TSA regulated the transcription of numerous innate immunity & tumor antigen recognition-associated genes, such as ULBP1 and RAET1G, in HCC cells. In vivo, TSA reduced tumor cell growth in an NK cell-dependent manner. In vitro, TSA treatment of HepG2 cells rendered them more susceptible to NK cell-mediated killing while increasing the expression of NKGD2 ligands, including ULBP1/2/3 and MICA/B. TSA also induced direct killing of HCC cells by stimulating apoptosis. TSA likely increases killing of HCC cells indirectly by increasing NK cell-directed killing and directly by increasing apoptosis. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

Trichostatin A Sensitizes Hepatocellular Carcinoma Cells to Enhanced NK Cell-mediated Killing by Regulating Immune-related Genes

PubMed Central

SHIN, SANGSU; KIM, MIOK; LEE, SEON-JIN; PARK, KANG-SEO

2017-01-01

Background/Aim: Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related death worldwide. The ability of HCC to avoid immune detection is considered one of the main factors making it difficult to cure. Abnormal histone deacetylation is thought to be one of the mechanisms for HCC immune escape, making histone deacetylases (HDACs) attractive targets for HCC treatment. Here, we investigated the effect of trichostatin A (TSA), a highly potent HDAC inhibitor, on HCC (HepG2) gene expression and function. Materials and Methods: A genome wide-transcriptional microarray was used to identify genes regulated by TSA in HepG2 cells. Gene Ontology was used to identify pathways regulated by TSA, and these changes were confirmed by qPCR. The effect of TSA on natural killer (NK) cell-mediated killing of HCC cell lines were analyzed by both flow cytometry and LDH cytotoxicity assay. A study was also conducted in a Balb/c nude mice xenograft model to assess the anti-tumor activity of TSA. Results: TSA regulated the transcription of numerous innate immunity & tumor antigen recognition-associated genes, such as ULBP1 and RAET1G, in HCC cells. In vivo, TSA reduced tumor cell growth in an NK cell-dependent manner. In vitro, TSA treatment of HepG2 cells rendered them more susceptible to NK cell-mediated killing while increasing the expression of NKGD2 ligands, including ULBP1/2/3 and MICA/B. TSA also induced direct killing of HCC cells by stimulating apoptosis. Conclusion: TSA likely increases killing of HCC cells indirectly by increasing NK cell-directed killing and directly by increasing apoptosis. PMID:28871002

Synergy between Common γ Chain Family Cytokines and IL-18 Potentiates Innate and Adaptive Pathways of NK Cell Activation

PubMed Central

Nielsen, Carolyn M.; Wolf, Asia-Sophia; Goodier, Martin R.; Riley, Eleanor M.

2016-01-01

Studies to develop cell-based therapies for cancer and other diseases have consistently shown that purified human natural killer (NK) cells secrete cytokines and kill target cells after in vitro culture with high concentrations of cytokines. However, these assays poorly reflect the conditions that are likely to prevail in vivo in the early stages of an infection and have been carried out in a wide variety of experimental systems, which has led to contradictions within the literature. We have conducted a detailed kinetic and dose–response analysis of human NK cell responses to low concentrations of IL-12, IL-15, IL-18, IL-21, and IFN-α, alone and in combination, and their potential to synergize with IL-2. We find that very low concentrations of both innate and adaptive common γ chain cytokines synergize with equally low concentrations of IL-18 to drive rapid and potent NK cell CD25 and IFN-γ expression; IL-18 and IL-2 reciprocally sustain CD25 and IL-18Rα expression in a positive feedback loop; and IL-18 synergizes with FcγRIII (CD16) signaling to augment antibody-dependent cellular cytotoxicity. These data indicate that NK cells can be rapidly activated by very low doses of innate cytokines and that the common γ chain cytokines have overlapping but distinct functions in combination with IL-18. Importantly, synergy between multiple signaling pathways leading to rapid NK cell activation at very low cytokine concentrations has been overlooked in prior studies focusing on single cytokines or simple combinations. Moreover, although the precise common γ chain cytokines available during primary and secondary infections may differ, their synergy with both IL-18 and antigen–antibody immune complexes underscores their contribution to NK cell activation during innate and adaptive responses. IL-18 signaling potentiates NK cell effector function during innate and adaptive immune responses by synergy with IL-2, IL-15, and IL-21 and immune complexes. PMID:27047490

HMGB1 Is Involved in IFN-α Production and TRAIL Expression by HIV-1-Exposed Plasmacytoid Dendritic Cells: Impact of the Crosstalk with NK Cells

PubMed Central

Formaglio, Pauline; Melki, Marie-Thérèse; Charbit, Bruno; Herbeuval, Jean-Philippe; Gougeon, Marie-Lise

2016-01-01

Plasmacytoid dendritic cells (pDCs) are innate sensors of viral infections and important mediators of antiviral innate immunity through their ability to produce large amounts of IFN-α. Moreover, Toll-like receptor 7 (TLR7) and 9 (TLR9) ligands, such as HIV and CpG respectively, turn pDCs into TRAIL-expressing killer pDCs able to lyse HIV-infected CD4+ T cells. NK cells can regulate antiviral immunity by modulating pDC functions, and pDC production of IFN-α as well as cell–cell contact is required to promote NK cell functions. Impaired pDC-NK cell crosstalk was reported in the setting of HIV-1 infection, but the impact of HIV-1 on TRAIL expression and innate antiviral immunity during this crosstalk is unknown. Here, we report that low concentrations of CCR5-tropic HIV-1Ba-L promote the release of pro-inflammatory cytokines such as IFN-α, TNF-α, IFN-γ and IL-12, and CCR5-interacting chemokines (MIP-1α and MIP-1β) in NK-pDCs co-cultures. At high HIV-1BaL concentrations, the addition of NK cells did not promote the release of these mediators, suggesting that once efficiently triggered by the virus, pDCs could not integrate new activating signals delivered by NK cells. However, high HIV-1BaL concentrations were required to trigger IFN-α-mediated TRAIL expression at the surface of both pDCs and NK cells during their crosstalk. Interestingly, we identified the alarmin HMGB1, released at pDC-NK cell synapse, as an essential trigger for the secretion of IFN-α and IFN-related soluble mediators during the interplay of HIV-1 exposed pDCs with NK cells. Moreover, HMGB1 was found crucial for mTRAIL translocation to the plasma membrane of both pDCs and NK cells during their crosstalk following pDC exposure to HIV-1. Data from serum analyses of circulating HMGB1, HMGB1-specific antibodies, sTRAIL and IP-10 in a cohort of 67 HIV-1+ patients argue for the in vivo relevance of these observations. Altogether, these findings identify HMGB1 as a trigger for IFN-α-mediated TRAIL expression at the surface of pDCs and NK cells, and they suggest a novel mechanism of innate control of HIV-1 infection. PMID:26871575

Characterisation of cell functions and receptors in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME).

PubMed

Hardcastle, Sharni Lee; Brenu, Ekua Weba; Johnston, Samantha; Nguyen, Thao; Huth, Teilah; Wong, Naomi; Ramos, Sandra; Staines, Donald; Marshall-Gradisnik, Sonya

2015-06-02

Abnormal immune function is often an underlying component of illness pathophysiology and symptom presentation. Functional and phenotypic immune-related alterations may play a role in the obscure pathomechanism of Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). The objective of this study was to investigate the functional ability of innate and adaptive immune cells in moderate and severe CFS/ME patients. The 1994 Fukuda criteria for CFS/ME were used to define CFS/ME patients. CFS/ME participants were grouped based on illness severity with 15 moderately affected (moderate) and 12 severely affected (severe) CFS/ME patients who were age and sex matched with 18 healthy controls. Flow cytometric protocols were used for immunological analysis of dendritic cells, monocytes and neutrophil function as well as measures of lytic proteins and T, natural killer (NK) and B cell receptors. CFS/ME patients exhibited alterations in NK receptors and adhesion markers and receptors on CD4(+)T and CD8(+)T cells. Moderate CFS/ME patients had increased CD8(+) CD45RA effector memory T cells, SLAM expression on NK cells, KIR2DL5(+) on CD4(+)T cells and BTLA4(+) on CD4(+)T central memory cells. Moderate CFS/ME patients also had reduced CD8(+)T central memory LFA-1, total CD8(+)T KLRG1, naïve CD4(+)T KLRG1 and CD56(dim)CD16(-) NK cell CD2(+) and CD18(+)CD2(+). Severe CFS/ME patients had increased CD18(+)CD11c(-) in the CD56(dim)CD16(-) NK cell phenotype and reduced NKp46 in CD56(bright)CD16(dim) NK cells. This research accentuated the presence of immunological abnormalities in CFS/ME and highlighted the importance of assessing functional parameters of both innate and adaptive immune systems in the illness.

The natural killer cell response to West Nile virus in young and old individuals with or without a prior history of infection.

PubMed

Yao, Yi; Strauss-Albee, Dara M; Zhou, Julian Q; Malawista, Anna; Garcia, Melissa N; Murray, Kristy O; Blish, Catherine A; Montgomery, Ruth R

2017-01-01

West Nile virus (WNV) typically leads to asymptomatic infection but can cause severe neuroinvasive disease or death, particularly in the elderly. Innate NK cells play a critical role in antiviral defenses, yet their role in human WNV infection is poorly defined. Here we demonstrate that NK cells mount a robust, polyfunctional response to WNV characterized by cytolytic activity, cytokine and chemokine secretion. This is associated with downregulation of activating NK cell receptors and upregulation of NK cell activating ligands for NKG2D. The NK cell response did not differ between young and old WNV-naïve subjects, but a history of symptomatic infection is associated with more IFN-γ producing NK cell subsets and a significant decline in a specific NK cell subset. This NK repertoire skewing could either contribute to or follow heightened immune pathogenesis from WNV infection, and suggests that NK cells could play an important role in WNV infection in humans.

Antiviral activity of NK 1.1+ natural killer cells in C57BL/6 scid mice infected with murine cytomegalovirus.

PubMed

Welsh, R M; O'Donnell, C L; Shultz, L D

1994-01-01

The activation, proliferation, and antiviral effects of natural killer (NK) cells were examined in a newly developed stock of mice, C57BL/6JSz mice homozygous for the severe combined immunodeficiency (scid) mutation. These mice lack functional T and B cells and express the NK 1.1 alloantigen. Such NK 1.1 expression facilitates the analysis of NK cells and their depletion in vivo with a monoclonal anti-NK 1.1 antibody. These mice, therefore, provide an excellent model to examine unambiguously the interactions between viral infections and NK cells in a system devoid of adaptive immune response mechanisms. Here we show that murine cytomegalovirus (MCMV) and lymphocytic choriomeningitis virus (LCMV) infections resulted in profound levels of NK cell activation. NK cells also proliferated greatly in response to LCMV but generally to a lesser degree in response to MCMV. Depletion of the NK cell activity in vivo caused substantial increases in MCMV synthesis and MCMV-induced pathology. These results further support the concept that NK cells are major regulators of MCMV pathogenesis.

A high-throughput assay of NK cell activity in whole blood and its clinical application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Saet-byul; Cha, Junhoe; Kim, Im-kyung

2014-03-14

Graphical abstract: - Highlights: • We demonstrated a simple assay of NK cell activity from whole blood. • The measurement of secreted IFN-γ from NK cell enables high-throughput screening. • The NKA assay was validated by clinical results of colorectal cancer patients. - Abstract: Natural killer (NK) cells are lymphocytes of the innate immune system and have the ability to kill tumor cells and virus-infected cells without prior sensitization. Malignant tumors and viruses have developed, however, strategies to suppress NK cells to escape from their responses. Thus, the evaluation of NK cell activity (NKA) could be invaluable to estimate themore » status and the outcome of cancers, viral infections, and immune-mediated diseases. Established methods that measure NKA, such as {sup 51}Cr release assay and CD107a degranulation assay, may be used to determine NK cell function, but they are complicated and time-consuming because they require isolation of peripheral blood mononuclear cells (PBMC) or NK cells. In some cases these assays require hazardous material such as radioactive isotopes. To overcome these difficulties, we developed a simple assay that uses whole blood instead of PBMC or isolated NK cells. This novel assay is suitable for high-throughput screening and the monitoring of diseases, because it employs serum of ex vivo stimulated whole blood to detect interferon (IFN)-γ secreted from NK cells as an indicator of NKA. After the stimulation of NK cells, the determination of IFNγ concentration in serum samples by enzyme-linked immunosorbent assay (ELISA) provided a swift, uncomplicated, and high-throughput assay of NKA ex vivo. The NKA results microsatellite stable (MSS) colorectal cancer patients was showed significantly lower NKA, 263.6 ± 54.5 pg/mL compared with healthy subjects, 867.5 ± 50.2 pg/mL (p value <0.0001). Therefore, the NKA could be utilized as a supportive diagnostic marker for microsatellite stable (MSS) colorectal cancer.« less

A Role for NKG2D in NK Cell–Mediated Resistance to Poxvirus Disease

PubMed Central

Fang, Min; Lanier, Lewis L; Sigal, Luis J

2008-01-01

Ectromelia virus (ECTV) is an orthopoxvirus (OPV) that causes mousepox, the murine equivalent of human smallpox. C57BL/6 (B6) mice are naturally resistant to mousepox due to the concerted action of innate and adaptive immune responses. Previous studies have shown that natural killer (NK) cells are a component of innate immunity that is essential for the B6 mice resistance to mousepox. However, the mechanism of NK cell–mediated resistance to OPV disease remains undefined. Here we show that B6 mice resistance to mousepox requires the direct cytolytic function of NK cells, as well as their ability to boost the T cell response. Furthermore, we show that the activating receptor NKG2D is required for optimal NK cell–mediated resistance to disease and lethality. Together, our results have important implication towards the understanding of natural resistance to pathogenic viral infections. PMID:18266471

Proinflammatory tachykinins that signal through the neurokinin 1 receptor promote survival of dendritic cells and potent cellular immunity.

PubMed

Janelsins, Brian M; Mathers, Alicia R; Tkacheva, Olga A; Erdos, Geza; Shufesky, William J; Morelli, Adrian E; Larregina, Adriana T

2009-03-26

Dendritic cells (DCs) are the preferred targets for immunotherapy protocols focused on stimulation of cellular immune responses. However, regardless of initial promising results, ex vivo generated DCs do not always promote immune-stimulatory responses. The outcome of DC-dependent immunity is regulated by proinflammatory cytokines and neuropeptides. Proinflammatory neuropeptides of the tachykinin family, including substance P (SP) and hemokinin-1 (HK-1), bind the neurokinin 1 receptor (NK1R) and promote stimulatory immune responses. Nevertheless, the ability of pro-inflammatory tachykinins to affect the immune functions of DCs remains elusive. In the present work, we demonstrate that mouse bone marrow-derived DCs (BMDCs) generated in the presence of granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin-4 (IL-4), express functional NK1R. Signaling via NK1R with SP, HK-1, or the synthetic agonist [Sar(9)Met(O(2))(11)]-SP rescues DCs from apoptosis induced by deprivation of GM-CSF and IL-4. Mechanistic analysis demonstrates that NK1R agonistic binding promotes DC survival via PI3K-Akt signaling cascade. In adoptive transfer experiments, NK1R-signaled BMDCs loaded with Ag exhibit increased longevity in draining lymph nodes, resulting in enhanced and prolonged effector cellular immunity. Our results contribute to the understanding of the interactions between the immune and nervous systems that control DC function and present a novel approach for ex vivo-generation of potent immune-stimulatory DCs.

Saliva exosomes from pancreatic tumor-bearing mice modulate NK cell phenotype and antitumor cytotoxicity.

PubMed

Katsiougiannis, Stergios; Chia, David; Kim, Yong; Singh, Ram P; Wong, David T W

2017-03-01

Tumor exosomes are emerging as antitumor immunity regulators; however, their effects on secondary exosome secretion by distal organs have not been explored. We have previously demonstrated that suppression of exosomes at the distal tumor site of pancreatic ductal adenocarcinoma (PDAC) ablated the development of salivary biomarker profile. Here, we explore the function of salivary exosomes from tumor-bearing mice in immune surveillance. We provide evidence that salivary exosomes from mice with PDAC exhibit a suppressive effect that results in reduced tumor-killing capacity by NK cells. Salivary exosomes from mice with PDAC where pancreatic tumors were engineered to suppress exosome biogenesis failed to suppress NK cell cytotoxic potential against tumor cells, as opposed to salivary exosomes from mice with PDAC with normal tumor exosome biogenesis. These results reveal an important and previously unknown mechanism of antitumor immune regulation and provide new insights into our understanding of the alterations of this biofluid during tumor development.-Katsiougiannis, S., Chia, D., Kim, Y., Singh, R. P., Wong, D. T. W. Saliva exosomes from pancreatic tumor-bearing mice modulate NK cell phenotype and antitumor cytotoxicity. © FASEB.

Escape of HIV-1-infected dendritic cells from TRAIL-mediated NK cell cytotoxicity during NK-DC cross-talk--a pivotal role of HMGB1.

PubMed

Melki, Marie-Thérèse; Saïdi, Héla; Dufour, Alexandre; Olivo-Marin, Jean-Christophe; Gougeon, Marie-Lise

2010-04-15

Early stages of Human Immunodeficiency Virus-1 (HIV-1) infection are associated with local recruitment and activation of important effectors of innate immunity, i.e. natural killer (NK) cells and dendritic cells (DCs). Immature DCs (iDCs) capture HIV-1 through specific receptors and can disseminate the infection to lymphoid tissues following their migration, which is associated to a maturation process. This process is dependent on NK cells, whose role is to keep in check the quality and the quantity of DCs undergoing maturation. If DC maturation is inappropriate, NK cells will kill them ("editing process") at sites of tissue inflammation, thus optimizing the adaptive immunity. In the context of a viral infection, NK-dependent killing of infected-DCs is a crucial event required for early elimination of infected target cells. Here, we report that NK-mediated editing of iDCs is impaired if DCs are infected with HIV-1. We first addressed the question of the mechanisms involved in iDC editing, and we show that cognate NK-iDC interaction triggers apoptosis via the TNF-related apoptosis-inducing ligand (TRAIL)-Death Receptor 4 (DR4) pathway and not via the perforin pathway. Nevertheless, once infected with HIV-1, DC(HIV) become resistant to NK-induced TRAIL-mediated apoptosis. This resistance occurs despite normal amounts of TRAIL released by NK cells and comparable DR4 expression on DC(HIV). The escape of DC(HIV) from NK killing is due to the upregulation of two anti-apoptotic molecules, the cellular-Flice like inhibitory protein (c-FLIP) and the cellular inhibitor of apoptosis 2 (c-IAP2), induced by NK-DC(HIV) cognate interaction. High-mobility group box 1 (HMGB1), an alarmin and a key mediator of NK-DC cross-talk, was found to play a pivotal role in NK-dependent upregulation of c-FLIP and c-IAP2 in DC(HIV). Finally, we demonstrate that restoration of DC(HIV) susceptibility to NK-induced TRAIL killing can be obtained either by silencing c-FLIP and c-IAP2 by specific siRNA, or by inhibiting HMGB1 with blocking antibodies or glycyrrhizin, arguing for a key role of HMGB1 in TRAIL resistance and DC(HIV) survival. These findings provide evidence for a new strategy developed by HIV to escape immune attack, they challenge the question of the involvement of HMGB1 in the establishment of viral reservoirs in DCs, and they identify potential therapeutic targets to eliminate infected DCs.

Immune defects in families and patients with xeroderma pigmentosum and trichothiodystrophy.

PubMed Central

Mariani, E; Facchini, A; Honorati, M C; Lalli, E; Berardesca, E; Ghetti, P; Marinoni, S; Nuzzo, F; Astaldi Ricotti, G C; Stefanini, M

1992-01-01

Xeroderma pigmentosum (XP) is a rare autosomal recessive disease characterized by photosensitivity, a high incidence of cancer in sun-exposed portions of the skin and a reduced capacity to repair the u.v.-induced DNA damage. One of the XP mutations (XP-D) has also been identified in patients affected by trichothiodystrophy (TTD), a rare autosomal recessive disease characterized by brittle hair, mental and physical retardation, peculiar face and ichthyosis. However, in these patients there is no evidence of increased skin tumour incidence. Since an impairment of cell-mediated immunity has been proposed as a co-factor in the cancer proneness of XP patients, we investigated the involvement of immune defect(s) in five XP patients, five TTD patients, their parents, and 24 TTD relatives. We evaluated the phenotype of circulating lymphocytes, natural killer (NK) cell lytic activity, target cell binding of NK cells at single cell level and the effect of interferons (IFN) alpha and beta on NK cell activity. The relative proportion of CD3+ and CD4+ circulating lymphocytes was reduced in XP but not in TTD patients. NK cell lytic activity was decreased in XP patients and their mothers, but their fathers showed normal lytic activity. NK activity varied among TTD families: four out of five patients and their relatives presented low NK cell activity, and one family was normal. In TTD family members, NK activity increased after incubation with IFN-alpha or IFN-beta, but never reached normal values. In contrast, in XP patients and their mothers, the defect was almost completely corrected after in vitro incubation with IFN-alpha or IFN-beta. Our study indicates impaired NK lytic activity in the majority of TTD and XP patients and that this defect is present also in members of their families. In addition, XP patients present a low number of circulating T cells. These multiple abnormalities, together with DNA repair defects, could be related to the increased cancer risk in XP patients. PMID:1535035

Leveraging natural killer cells for cancer immunotherapy.

PubMed

Grossenbacher, Steven K; Aguilar, Ethan G; Murphy, William J

2017-05-01

Natural killer (NK) cells are potent antitumor effector cells of the innate immune system. Based on their ability to eradicate tumors in vitro and in animal models, significant enthusiasm surrounds the prospect of leveraging human NK cells as vehicles for cancer immunotherapy. While interest in manipulating the effector functions of NK cells has existed for over 30 years, there is renewed optimism for this approach today. Although T cells receive much of the clinical and preclinical attention when it comes to cancer immunotherapy, new strategies are utilizing adoptive NK-cell immunotherapy and monoclonal antibodies and engineered molecules which have been developed to specifically activate NK cells against tumors. Despite the numerous challenges associated with the preclinical and clinical development of NK cell-based therapies for cancer, NK cells possess many unique immunological properties and hold the potential to provide an effective means for cancer immunotherapy.

Characterization of a human anti-tumoral NK cell population expanded after BCG treatment of leukocytes

PubMed Central

García-Cuesta, Eva M.; Esteso, Gloria; Ashiru, Omodele; López-Cobo, Sheila; Álvarez-Maestro, Mario; Linares, Ana; Ho, Mei M.; Martínez-Piñeiro, Luis; T. Reyburn, Hugh; Valés-Gómez, Mar

2017-01-01

ABSTRACT Immunotherapy, via intra-vesical instillations of BCG, is the therapy of choice for patients with high-risk non-muscle invasive bladder cancer. The subsequent recruitment of lymphocytes and myeloid cells, as well as the release of cytokines and chemokines, is believed to induce a local immune response that eliminates these tumors, but the detailed mechanisms of action of this therapy are not well understood. Here, we have studied the phenotype and function of the responding lymphocyte populations as well as the spectrum of cytokines and chemokines produced in an in vitro model of human peripheral blood mononuclear cells (PBMCs) co-cultured with BCG. Natural killer (NK) cell activation was a prominent feature of this immune response and we have studied the expansion of this lymphocyte population in detail. We show that, after BCG stimulation, CD56dim NK cells proliferate, upregulate CD56, but maintain the expression of CD16 and the ability to mediate ADCC. CD56bright NK cells also contribute to this expansion by increasing CD16 and KIR expression. These unconventional CD56bright cells efficiently degranulated against bladder cancer cells and the expansion of this population required the release of soluble factors by other immune cells in the context of BCG. Consistent with these in vitro data, a small, but significant increase in the intensity of CD16 expression was noted in peripheral blood CD56bright cells from bladder cancer patients undergoing BCG therapy, that was not observed in patients treated with mitomycin-C instillations. These observations suggest that activation of NK cells may be an important component of the anti-tumoral immune response triggered by BCG therapy in bladder cancer. PMID:28507799

Role of natural killer cells in lung cancer.

PubMed

Aktaş, Ozge Nur; Öztürk, Ayşe Bilge; Erman, Baran; Erus, Suat; Tanju, Serhan; Dilege, Şükrü

2018-06-01

One of the key immune cells involved in the pathogenesis of lung cancer is natural killer (NK) cells and these cells are novel targets for therapeutic applications in lung cancer. The purpose of this review is to summarize the current literature on lung cancer pathogenesis with a focus on the interaction between NK cells and smoking, how these factors are related to the pathogenesis of lung cancer and how NK cell-based immunotherapy effect lung cancer survival. The relevant literature from PubMed and Medline databases is reviewed in this article. The cytolytic potential of NK cells are reduced in lung cancer and increasing evidence suggests that improving NK cell functioning may induce tumor regression. Recent clinical trials on NK cell-based novel therapies such as cytokines including interleukin (IL)-15, IL-12 and IL-2, NK-92 cell lines and allogenic NK cell immunotherapy showed promising results with less adverse effects on the lung cancer survival. The NK cell targeting strategy has not yet been approved for lung cancer treatment. More clinical studies focusing on the role of NK cells in lung cancer pathogenesis are warranted to develop novel NK cell-based therapeutic approaches for the treatment of lung cancer.

Increased IFN-gamma production by NK and CD3+/CD56+ cells in sexually HIV-1-exposed but uninfected individuals.

PubMed

Montoya, Carlos Julio; Velilla, Paula Andrea; Chougnet, Claire; Landay, Alan L; Rugeles, Maria Teresa

2006-08-01

The mechanisms involved in controlling the establishment of HIV-1 infection are not fully understood. In particular, the role of innate immunity in natural resistance exhibited by individuals who are continuously exposed to HIV-1 but remain seronegative (ESN) has not been thoroughly evaluated. We determined the frequency and function of peripheral blood innate immune cells (plasmacytoid and myeloid dendritic cells, monocytes, NK cells, CD3+/CD56+ cells and invariant NKT cells) in ESN, chronically HIV-1-infected and low-risk HIV-1 seronegative individuals. ESN demonstrated a similar frequency of innate immune cells in comparison to controls and a higher frequency of dendritic cells, NK and invariant NKT cells compared to HIV-1-infected subjects. Incubation of mononuclear cells with stimulatory CpG ODN induced CD86 and CD69 up-regulation to a similar degree on innate cells from the three study groups. CpG ODN-stimulated secretion of cytokines was also similar between ESN and controls, while secretion of IFN-alpha was significantly decreased in HIV-1+ individuals. Importantly, expression of IFN-gamma by PMA/Ionomycin-activated CD56(bright) NK cells and CD3+/CD56+ cells was significantly higher in ESN when compared with controls. The anti-viral effects of IFN-gamma are well established, and so our results suggest that IFN-gamma production by innate immune cells might be one of the multiple factors involved in controlling the establishment of sexually transmitted HIV-1 infection.

TUSC2 Immunogene Therapy Synergizes with Anti-PD-1 through Enhanced Proliferation and Infiltration of Natural Killer Cells in Syngeneic Kras-Mutant Mouse Lung Cancer Models.

PubMed

Meraz, Ismail M; Majidi, Mourad; Cao, Xiaobo; Lin, Heather; Li, Lerong; Wang, Jing; Baladandayuthapani, Veera; Rice, David; Sepesi, Boris; Ji, Lin; Roth, Jack A

2018-02-01

Expression of the multikinase inhibitor encoded by the tumor suppressor gene TUSC2 (also known as FUS1 ) is lost or decreased in non-small cell lung carcinoma (NSCLC). TUSC2 delivered systemically by nanovesicles has mediated tumor regression in clinical trials. Because of the role of TUSC2 in regulating immune cells, we assessed TUSC2 efficacy on antitumor immune responses alone and in combination with anti-PD-1 in two Kras -mutant syngeneic mouse lung cancer models. TUSC2 alone significantly reduced tumor growth and prolonged survival compared with anti-PD-1. When combined, this effect was significantly enhanced, and correlated with a pronounced increases in circulating and splenic natural killer (NK) cells and CD8 + T cells, and a decrease in regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and T-cell checkpoint receptors PD-1, CTLA-4, and TIM-3. TUSC2 combined with anti-PD-1 induced tumor infiltrating more than NK and CD8 + T cells and fewer MDSCs and Tregs than each agent alone, both in subcutaneous tumor and in lung metastases. NK-cell depletion abrogated the antitumor effect and Th1-mediated immune response of this combination, indicating that NK cells mediate TUSC2/anti-PD-1 synergy. Release of IL15 and IL18 cytokines and expression of the IL15Rα chain and IL18R1 were associated with NK-cell activation by TUSC2. Immune response-related gene expression in the tumor microenvironment was altered by combination treatment. These data provide a rationale for immunogene therapy combined with immune checkpoint blockade in the treatment of NSCLC. Cancer Immunol Res; 6(2); 163-77. ©2018 AACR . ©2018 American Association for Cancer Research.

2B4 expression on natural killer cells increases in HIV-1 infected patients followed prospectively during highly active antiretroviral therapy

PubMed Central

Ostrowski, S R; Ullum, H; Pedersen, B K; Gerstoft, J; Katzenstein, T L

2005-01-01

Human immunodeficiency virus (HIV)-1 infection influences natural killer (NK) cell expression of inhibitory NK receptors and activating natural cytotoxicity receptors. It is unknown whether expression of the co-stimulatory NK cell receptor 2B4 (CD244) on NK cells and CD3+ CD8+ cells are affected by highly active antiretroviral therapy (HAART), low-level viraemia, proviral-DNA or immune activation in HIV-1 infected patients. A total of 101 HAART-treated HIV-1 infected patients with ≤ 200 HIV-RNA copies/ml were followed prospectively for 24 months. HIV-RNA was investigated 3-monthly and 2B4 expression on CD3− CD16+ NK cells and CD3+ CD8+ cells, proviral-DNA and plasma soluble tumour necrosis factor receptor (sTNFr)-II were investigated 6-monthly. For comparison, 2B4 expression was investigated in 20 healthy individuals. The concentration of 2B4+ NK cells was initially reduced in HIV-1 infected patients (P < 0·001) but increased to a normal level during the 24 months’ follow-up. The concentration of CD3+ CD8+ 2B4+ cells in HIV-1 infected patients was normal and did not change during follow-up. The relative fluorescence intensity (RFI) of 2B4 increased on both NK cells and CD3+ CD8+ cells during follow-up (both P < 0·001). Higher levels of proviral-DNA carrying cells and plasma sTNFrII were associated with reductions in the concentration of 2B4+ NK cells (all P < 0·05). HIV-RNA had no effect on 2B4 expression on NK cells or CD3+ CD8+ cells. These findings demonstrate that the concentration of 2B4+ NK cells normalizes during long-term HAART in HIV-1 infected patients. The finding that proviral-DNA and sTNFrII were associated negatively with the concentration of 2B4+ NK cells suggests that immune activation in HIV-1 infected patients receiving HAART influences the target cell recognition by NK cells. PMID:16045743

2B4 expression on natural killer cells increases in HIV-1 infected patients followed prospectively during highly active antiretroviral therapy.

PubMed

Ostrowski, S R; Ullum, H; Pedersen, B K; Gerstoft, J; Katzenstein, T L

2005-09-01

Human immunodeficiency virus (HIV)-1 infection influences natural killer (NK) cell expression of inhibitory NK receptors and activating natural cytotoxicity receptors. It is unknown whether expression of the co-stimulatory NK cell receptor 2B4 (CD244) on NK cells and CD3+ CD8+ cells are affected by highly active antiretroviral therapy (HAART), low-level viraemia, proviral-DNA or immune activation in HIV-1 infected patients. A total of 101 HAART-treated HIV-1 infected patients with < or = 200 HIV-RNA copies/ml were followed prospectively for 24 months. HIV-RNA was investigated 3-monthly and 2B4 expression on CD3- CD16+ NK cells and CD3+ CD8+ cells, proviral-DNA and plasma soluble tumour necrosis factor receptor (sTNFr)-II were investigated 6-monthly. For comparison, 2B4 expression was investigated in 20 healthy individuals. The concentration of 2B4+ NK cells was initially reduced in HIV-1 infected patients (P < 0.001) but increased to a normal level during the 24 months' follow-up. The concentration of CD3+ CD8+ 2B4+ cells in HIV-1 infected patients was normal and did not change during follow-up. The relative fluorescence intensity (RFI) of 2B4 increased on both NK cells and CD3+ CD8+ cells during follow-up (both P < 0.001). Higher levels of proviral-DNA carrying cells and plasma sTNFrII were associated with reductions in the concentration of 2B4+ NK cells (all P < 0.05). HIV-RNA had no effect on 2B4 expression on NK cells or CD3+ CD8+ cells. These findings demonstrate that the concentration of 2B4+ NK cells normalizes during long-term HAART in HIV-1 infected patients. The finding that proviral-DNA and sTNFrII were associated negatively with the concentration of 2B4+ NK cells suggests that immune activation in HIV-1 infected patients receiving HAART influences the target cell recognition by NK cells.

Isolation and (111)In-Oxine Labeling of Murine NK Cells for Assessment of Cell Trafficking in Orthotopic Lung Tumor Model.

PubMed

Malviya, Gaurav; Nayak, Tapan; Gerdes, Christian; Dierckx, Rudi A J O; Signore, Alberto; de Vries, Erik F J

2016-04-04

A noninvasive in vivo imaging method for NK cell trafficking is essential to gain further understanding of the pathogenesis of NK cell mediated immune response to the novel cancer treatment strategies, and to discover the homing sites and physiological distribution of NK cells. Although human NK cells can be labeled for in vivo imaging, little is known about the murine NK cell labeling and its application in animal models. This study describes the isolation and ex vivo radiolabeling of murine NK cells for the evaluation of cell trafficking in an orthotopic model of human lung cancer in mice. Scid-Tg(FCGR3A)Blt transgenic SCID mice were used to isolate NK cells from mouse splenocytes using the CD49b (DX5) MicroBeads positive selection method. The purity and viability of the isolated NK cells were confirmed by FACS analysis. Different labeling buffers and incubation times were evaluated to optimize (111)In-oxine labeling conditions. Functionality of the radiolabeled NK cell was assessed by (51)Cr-release assay. We evaluated physiological distribution of (111)In-oxine labeled murine NK cells in normal SCID mice and biodistribution in irradiated and nonirradiated SCID mice with orthotopic A549 human lung tumor lesions. Imaging findings were confirmed by histology. Results showed that incubation with 0.011 MBq of (111)In-oxine per million murine NK cells in PBS (pH 7.4) for 20 min is the best condition that provides optimum labeling efficiency without affecting cell viability and functionality. Physiological distribution in normal SCID mice demonstrated NK cells homing mainly in the spleen, while (111)In released from NK cells was excreted via kidneys into urine. Biodistribution studies demonstrated a higher lung uptake in orthotopic lung tumor-bearing mice than control mice. In irradiated mice, lung tumor uptake of radiolabeled murine NK cells decreased between 24 h and 72 h postinjection (p.i.), which was accompanied by tumor regression, while in nonirradiated mice, radiolabeled NK cells were retained in the lung tumor lesions up to 72 h p.i. without tumor regression. In tumor-bearing mice that were only irradiated but did not receive radiolabeled murine NK cells, a high tumor burden was observed at 72 h p.i., which indicates that irradiation in combination with murine NK cell allocation, but not irradiation alone, induced a remarkable antitumor effect in the orthotopic A549 lung tumor bearing mouse model. In conclusion, we describe a method to evaluate murine NK cell trafficking and biodistribution, which can be used to determine potential effects of immune-mediated therapeutic agents on NK cell biodistribution.

Rhizopus oryzae hyphae are damaged by human natural killer (NK) cells, but suppress NK cell mediated immunity.

PubMed

Schmidt, Stanislaw; Tramsen, Lars; Perkhofer, Susanne; Lass-Flörl, Cornelia; Hanisch, Mitra; Röger, Frauke; Klingebiel, Thomas; Koehl, Ulrike; Lehrnbecher, Thomas

2013-07-01

Mucormycosis has a high mortality and is increasingly diagnosed in hematopoietic stem cell transplant (HSCT) recipients. In this setting, there is a growing interest to restore host defense to combat infections by adoptively transferring donor-derived immunocompetent cells. Natural killer (NK) cells exhibit antitumor and antiinfective activity, but the interaction with Mucormycetes is unknown. Our data demonstrate that both unstimulated and IL-2 prestimulated human NK cells damage Rhizopus oryzae hyphae, but do not affect resting conidia. The damage of the fungus is mediated, at least in part, by perforin. R. oryzae hyphae decrease the secretion of immunoregulatory molecules by NK cells, such as IFN-γ and RANTES, indicating an immunosuppressive effect of the fungus. Our data indicate that NK cells exhibit activity against Mucormycetes and future research should evaluate NK cells as a potential tool for adoptive immunotherapy in HSCT. Copyright © 2012 Elsevier GmbH. All rights reserved.

Immune Reconstitution After Allogeneic Hematopoietic Stem Cell Transplantation and Association With Occurrence and Outcome of Invasive Aspergillosis.

PubMed

Stuehler, Claudia; Kuenzli, Esther; Jaeger, Veronika K; Baettig, Veronika; Ferracin, Fabrizia; Rajacic, Zarko; Kaiser, Deborah; Bernardini, Claudia; Forrer, Pascal; Weisser, Maja; Elzi, Luigia; Battegay, Manuel; Halter, Joerg; Passweg, Jakob; Khanna, Nina

2015-09-15

Invasive aspergillosis (IA) remains a leading cause of morbidity and mortality in patients receiving allogeneic hematopoietic stem cell transplantation (HSCT). To date, no reliable immunological biomarkers for management and outcome of IA exist. Here, we investigated reconstitution of antifungal immunity in patients during the first 12 months after HSCT and correlated it with IA. Fifty-one patients were included, 9 with probable/proven IA. We determined quantitative and qualitative reconstitution of polymorphonuclear (PMN), CD4, CD8, and natural killer (NK) cells against Aspergillus fumigatus over 5 time points and compared the values to healthy donors. Absolute CD4 and CD8 cell counts, antigen-specific T-cell responses, and killing capacity of PMN against A. fumigatus were significantly decreased in all patients over 12 months. In patients with probable/proven IA, reactive oxygen species (ROS) production tended to be lower compared to patients without IA, and absolute NK-cell counts remained below 200 cells/µL. Patients with well-controlled IA showed significantly higher ROS production and NK-cell counts compared to patients with poor outcome. This study highlights the importance of functional PMN, T-cell, and NK-cell immunity for the outcome of IA. Larger multicenter studies should address the potential use of NK-cell counts for the management of antifungal therapy. © The Author 2015. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Characterization of tumor infiltrating Natural Killer cell subset

PubMed Central

Nissan, Aviram; Darash-Yahana, Merav; Peretz, Tamar; Mandelboim, Ofer; Rachmilewitz, Jacob

2015-01-01

The presence of tumor-infiltrating Natural Killer (NK) within a tumor bed may be indicative of an ongoing immune response toward the tumor. However, many studies have shown that an intense NK infiltration, is associated with advanced disease and may even facilitate cancer development. The exact role of the tumor infiltrating NK cells and the correlation between their presence and poor prognosis remains unclear. Interestingly, during pregnancy high numbers of a specific NK subset, CD56brightCD16dim, are accumulated within first trimester deciduas. These decidual NK (dNK) cells are unique in their gene expression pattern secret angiogenic factors that induce vascular growth. In the present study we demonstrate a significant enrichment of a CD56brighCD16dim NK cells within tumors. These NK cells express several dNK markers including VEGF. Hence, this study adds new insights into the identity of tumor residual NK cells, which has clear implications for the treatment of human cancer. PMID:26079948

The natural product phyllanthusmin C enhances IFN-γ production by human NK cells through upregulation of TLR-mediated NF-κB signaling.

PubMed

Deng, Youcai; Chu, Jianhong; Ren, Yulin; Fan, Zhijin; Ji, Xiaotian; Mundy-Bosse, Bethany; Yuan, Shunzong; Hughes, Tiffany; Zhang, Jianying; Cheema, Baljash; Camardo, Andrew T; Xia, Yong; Wu, Lai-Chu; Wang, Li-Shu; He, Xiaoming; Kinghorn, A Douglas; Li, Xiaohui; Caligiuri, Michael A; Yu, Jianhua

2014-09-15

Natural products are a major source for cancer drug development. NK cells are a critical component of innate immunity with the capacity to destroy cancer cells, cancer-initiating cells, and clear viral infections. However, few reports describe a natural product that stimulates NK cell IFN-γ production and unravel a mechanism of action. In this study, through screening, we found that a natural product, phyllanthusmin C (PL-C), alone enhanced IFN-γ production by human NK cells. PL-C also synergized with IL-12, even at the low cytokine concentration of 0.1 ng/ml, and stimulated IFN-γ production in both human CD56(bright) and CD56(dim) NK cell subsets. Mechanistically, TLR1 and/or TLR6 mediated PL-C's activation of the NF-κB p65 subunit that in turn bound to the proximal promoter of IFNG and subsequently resulted in increased IFN-γ production in NK cells. However, IL-12 and IL-15Rs and their related STAT signaling pathways were not responsible for the enhanced IFN-γ secretion by PL-C. PL-C induced little or no T cell IFN-γ production or NK cell cytotoxicity. Collectively, we identify a natural product with the capacity to selectively enhance human NK cell IFN-γ production. Given the role of IFN-γ in immune surveillance, additional studies to understand the role of this natural product in prevention of cancer or infection in select populations are warranted. Copyright © 2014 by The American Association of Immunologists, Inc.

Natural Killer Cell Memory

PubMed Central

O’Sullivan, Timothy E.; Sun, Joseph C.; Lanier, Lewis L.

2015-01-01

Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner, and then undergo cell death. Recently, however, NK cells have been shown to possess traits of adaptive immunity, and can acquire immunological memory in a similar manner to T and B cells. In this review, we discuss evidence for NK cell memory and the mechanisms involved in the generation and survival of these innate lymphocytes. PMID:26488815

Antimicrobial activity of bovine NK-lysin-derived peptides on Mycoplasma bovis

USDA-ARS?s Scientific Manuscript database

Antimicrobial peptides (AMPs) are a diverse group of molecules which play an important role in the innate immune response. Bovine NK-lysins, a type of AMP, have been predominantly found in the granules of cytotoxic T-lymphocytes and NK-cells. Bovine NK-lysin-derived peptides demonstrate antimicrobia...

Compartmentalisation of innate immune responses in the central nervous system during cryptococcal meningitis/HIV co-infection

PubMed Central

NARANBHAI, Vivek; CHANG, Christina C.; DURGIAH, Raveshni; OMARJEE, Saleha; LIM, Andrew; MOOSA, Mahomed-Yunus S.; ELLIOT, Julian H.; NDUNG’U, Thumbi; LEWIN, Sharon R.; FRENCH, Martyn A.; CARR, William H.

2014-01-01

Objective The role of innate immunity in pathogenesis of cryptococcal meningitis (CM) is unclear. We hypothesised that NK cell and monocyte responses are central nervous system (CNS) compartmentalised, and altered by anti-fungal therapy and combination antiretroviral therapy (cART) during CM/HIV co-infection. Design Sub-study of a prospective cohort study of adults with CM/HIV co-infection in Durban, South Africa. Methods We used multi-parametric flow cytometry to study compartmentalisation of subsets, activation (CD69pos), CXCR3 and CX3CR1 expression and cytokine secretion of NK cells and monocytes in freshly collected blood and cerebrospinal fluid (CSF) at diagnosis (n=23), completion of anti-fungal therapy induction (n=19) and after a further 4 weeks of cART (n=9). Results Relative to blood, CSF was enriched with CD56bright (immunoregulatory) NK cells (p=0.0004). At enrolment, CXCR3 expression was more frequent amongst blood CD56bright than either blood CD56dim (p<0.0001) or CSF CD56bright (p=0.0002) NK cells. Anti-fungal therapy diminished blood (p<0.05) but not CSF CXCR3pos NK cell proportions nor CX3CR1pos NK cell proportions. CD56bright and CD56dim NK cells were more activated in CSF than blood (p<0.0001). Anti-fungal therapy induction reduced CD56dim NK cell activation in CSF (p=0.02). Activation of blood CD56bright and CD56dim NK cells was diminished following cART commencement (p<0.0001, p=0.03). Immunoregulatory NK cells in CSF tended to secrete higher levels of CXCL10 (p=0.06) and lower levels of TNF-α (p=0.06) than blood immunoregulatory NK cells. CSF was enriched with non-classical monocytes (p=0.001), but anti-fungal therapy restored proportions of classical monocytes (p=0.007). Conclusions These results highlight CNS activation, trafficking and function of NK cells and monocytes in CM/HIV and implicate immunoregulatory NK cells and pro-inflammatory monocytes as potential modulators of CM pathogenesis during HIV co-infection. PMID:24451162

The Natural Product Phyllanthusmin C Enhances IFN-γ Production by Human Natural Killer Cells through Upregulation of TLR-Mediated NF-κB Signaling

PubMed Central

Deng, Youcai; Chu, Jianhong; Ren, Yulin; Fan, Zhijin; Ji, Xiaotian; Mundy, Bethany; Yuan, Shunzong; Hughes, Tiffany; Zhang, Jianying; Cheema, Baljash; Camardo, Andrew T.; Xia, Yong; Wu, Lai-Chu; Wang, Li-Shu; He, Xiaoming; Kinghorn, A. Douglas; Li, Xiaohui; Caligiuri, Michael A; Yu, Jianhua

2014-01-01

Natural products are a major source for cancer drug development. NK cells are a critical component of innate immunity with the capacity to destroy cancer cells, cancer initiating cells, and clear viral infections. However, few reports describe a natural product that selectively stimulates NK cell IFN-γ production and unravel a mechanism of action. In this study, through screening, we found that a natural product, phyllanthusmin C (PL-C), alone enhanced IFN-γ production by human NK cells. PL-C also synergized with IL-12, even at the low cytokine concentration of 0.1 mg/ml, and stimulated IFN-γ production in both human CD56bright and CD56dim NK cell subsets. Mechanistically, TLR1 and/or TLR6 mediated PL-C’s activation of the NF-κB p65 subunit that in turn bound to the proximal promoter of IFNG and subsequently resulted in increased IFN-γ production in NK cells. However, IL-12/IL-15 receptors and their related STAT signaling pathways were not significantly modulated by PL-C. PL-C induced little or no T cell IFN-γ production or NK cell cytotoxicity. Collectively, we identify a natural product with the capacity to selectively activate human NK cell IFN-γ. Given the role of IFN-γ in immune surveillance, additional studies to understand the role of this natural product in prevention of cancer or infection in select populations are warranted. PMID:25122922

Cancer Immunology at the Crossroads: Killer immunoglobulin-like receptors and tumor immunity

PubMed Central

Benson, Don M; Caligiuri, Michael A

2014-01-01

Natural killer (NK) cells, large granular lymphocytes comprising a key cellular subset of innate immunity, were originally named for their capacity to elicit potent cytotoxicity against tumor cells independent of prior sensitization or gene rearrangement. This process is facilitated through the expression of activating and inhibitory receptors that provide for NK cell “education” and a subsequent ability to survey, recognize and lyse infected or transformed cells, especially those lacking or possessing mutated major histocompatibility complex (MHC) class I expression. Since these original observations were made, how NK cells recognize candidate target cells continues to be the topic of ongoing investigation. It is now appreciated that NK cells express a diverse repertoire of activating and inhibitory receptors of which killer immunoglobulin-like receptors (KIR) appear to play a critical role in mediating self-tolerance as well as facilitating cytotoxicity against infected or transformed cells. Additionally, in the presence of an activating signal, the absence or mismatch of MHC class I molecules on such targets (which serve as inhibitory KIR ligands) promotes NK cell-mediated lysis. An increasing understanding of the complexities of KIR biology has provided recent opportunities to leverage the NK cell versus tumor effect as a novel avenue of therapeutic immunotherapy for cancer. The present review seeks to summarize the current understanding of KIR expression and function and highlight ongoing efforts to translate these discoveries into novel NK cell-mediated immunotherapies for cancer. PMID:24592397

Glutathione diminishes Dibutyltin- and tributyltin-induced loss of lytic function in human natural killer cells

PubMed Central

Powell, Jeralyn J.; Davis, McLisa V.; Whalen, Margaret M.

2008-01-01

This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an intital immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during exposure of NK cells to TBT or DBT diminished the negative effect of the BT on the lytic function of NK cells. This suggests that interaction TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function. PMID:18821099

Glutathione diminishes tributyltin- and dibutyltin-induced loss of lytic function in human natural killer cells.

PubMed

Powell, Jeralyn J; Davis, McLisa V; Whalen, Margaret M

2009-01-01

This study investigated whether reduced glutathione (GSH) was able to alter the negative effects of tributyltin (TBT) or dibutyltin (DBT) on the lytic function of human natural killer (NK) cells. NK cells are an initial immune defense against the development of tumors or viral infections. TBT and DBT are widespread environmental contaminants, due to their various industrial applications. Both TBT and DBT have been shown to decrease the ability of NK cells to lyse tumor cells (lytic function). The results indicated that the presence of GSH during the exposure of NK cells to TBT or DBT diminished the negative effect of the butyltin on the lytic function of NK cells. This suggests that the interaction of TBT and DBT with functionally relevant sulfhydryl groups in NK cells may be part of the mechanism by which they decrease NK lytic function.

Black Raspberries Enhance Natural Killer Cell Infiltration into the Colon and Suppress the Progression of Colorectal Cancer

PubMed Central

Pan, Pan; Kang, Siwen; Wang, Youwei; Liu, Ka; Oshima, Kiyoko; Huang, Yi-Wen; Zhang, Jianying; Yearsley, Martha; Yu, Jianhua; Wang, Li-Shu

2017-01-01

Natural killer (NK) cells are an essential component of innate immunity against cancer development. Many studies have been conducted to evaluate immune-modulating effects using dietary compounds. Our laboratory has been investigating the chemopreventive potential of black raspberries (BRBs) and previously demonstrated their beneficial modulation of genetic and epigenetic biomarkers in patients with colorectal cancer (CRC). The current study investigated their potential on modulating NK cells. To avoid the excessive inflammation caused by the dextran sulfate sodium (DSS) treatment that leads to colitis, we treated the mice with overnight DSS so that it would slightly irritate the colon but still promote colon carcinogenesis with 100% incidence in both the ApcMin/+ mice and azoxymethane (AOM)-treated mice. A significant decrease of tissue-infiltrating NK cells along the progression of microadenoma-to-adenoma and adenoma-to-adenocarcinoma was observed in the ApcMin/+/DSS and AOM/DSS mice, respectively. Depletion of NK cells significantly promoted the development of CRC, suggesting a critical role of NK cells in combating CRC progression. BRBs significantly suppressed the CRC progression and increased the number of tissue-infiltrating NK cells in both mouse models. Moreover, we further determined BRBs’ effects on NK cells in the human biopsy specimens collected from our previously completed clinical trial, in which CRC patients consumed BRBs for an average of 4 weeks during a presurgical window. We observed an increased number and an enhanced cytotoxicity of NK cells by BRB intervention. The current study provides evidence that BRBs have the potential to enhance the tumor immunesurveillance of NK cells that can be beneficial in the setting of CRC prevention and treatment. PMID:28861089

Screening NK-, B- and T-cell phenotype and function in patients suffering from Chronic Fatigue Syndrome.

PubMed

Curriu, Marta; Carrillo, Jorge; Massanella, Marta; Rigau, Josepa; Alegre, José; Puig, Jordi; Garcia-Quintana, Ana M; Castro-Marrero, Jesus; Negredo, Eugènia; Clotet, Bonaventura; Cabrera, Cecilia; Blanco, Julià

2013-03-20

Chronic Fatigue Syndrome (CFS) is a debilitating neuro-immune disorder of unknown etiology diagnosed by an array of clinical manifestations. Although several immunological abnormalities have been described in CFS, their heterogeneity has limited diagnostic applicability. Immunological features of CFS were screened in 22 CFS diagnosed individuals fulfilling Fukuda criteria and 30 control healthy individuals. Peripheral blood T, B and NK cell function and phenotype were analyzed by flow cytometry in both groups. CFS diagnosed individuals showed similar absolute numbers of T, B and NK cells, with minor differences in the percentage of CD4+ and CD8+ T cells. B cells showed similar subset frequencies and proliferative responses between groups. Conversely, significant differences were observed in T cell subsets. CFS individuals showed increased levels of T regulatory cells (CD25+/FOXP3+) CD4 T cells, and lower proliferative responses in vitro and in vivo. Moreover, CD8 T cells from the CFS group showed significantly lower activation and frequency of effector memory cells. No clear signs of T-cell immunosenescence were observed. NK cells from CFS individuals displayed higher expression of NKp46 and CD69 but lower expression of CD25 in all NK subsets defined. Overall, T cell and NK cell features clearly clustered CFS individuals. Our findings suggest that alterations in T-cell phenotype and proliferative response along with the specific signature of NK cell phenotype may be useful to identify CFS individuals. The striking down modulation of T cell mediated immunity may help to understand intercurrent viral infections in CFS.

Screening NK-, B- and T-cell phenotype and function in patients suffering from Chronic Fatigue Syndrome

PubMed Central

2013-01-01

Background Chronic Fatigue Syndrome (CFS) is a debilitating neuro-immune disorder of unknown etiology diagnosed by an array of clinical manifestations. Although several immunological abnormalities have been described in CFS, their heterogeneity has limited diagnostic applicability. Methods Immunological features of CFS were screened in 22 CFS diagnosed individuals fulfilling Fukuda criteria and 30 control healthy individuals. Peripheral blood T, B and NK cell function and phenotype were analyzed by flow cytometry in both groups. Results CFS diagnosed individuals showed similar absolute numbers of T, B and NK cells, with minor differences in the percentage of CD4+ and CD8+ T cells. B cells showed similar subset frequencies and proliferative responses between groups. Conversely, significant differences were observed in T cell subsets. CFS individuals showed increased levels of T regulatory cells (CD25+/FOXP3+) CD4 T cells, and lower proliferative responses in vitro and in vivo. Moreover, CD8 T cells from the CFS group showed significantly lower activation and frequency of effector memory cells. No clear signs of T-cell immunosenescence were observed. NK cells from CFS individuals displayed higher expression of NKp46 and CD69 but lower expression of CD25 in all NK subsets defined. Overall, T cell and NK cell features clearly clustered CFS individuals. Conclusions Our findings suggest that alterations in T-cell phenotype and proliferative response along with the specific signature of NK cell phenotype may be useful to identify CFS individuals. The striking down modulation of T cell mediated immunity may help to understand intercurrent viral infections in CFS. PMID:23514202

The Distinctive Sensitivity to Microgravity of Immune Cell Subpopulations

NASA Astrophysics Data System (ADS)

Chen, Hui; Luo, Haiying; Liu, Jing; Wang, Peng; Dong, Dandan; Shang, Peng; Zhao, Yong

2015-11-01

Immune dysfunction in astronauts is well documented after spaceflights. Microgravity is one of the key factors directly suppressing the function of immune system. However, it is unclear which subpopulations of immune cells including innate and adaptive immune cells are more sensitive to microgravity We herein investigated the direct effects of modeled microgravity (MMg) on different immune cells in vitro. Mouse splenocytes, thymocytes and bone marrow cells were exposed to MMg for 16 hrs. The survival and the phenotypes of different subsets of immune cells including CD4+T cells, CD8+T cells, CD4+Foxp3+ regulatory T cells (Treg), B cells, monocytes/macrophages, dendritic cells (DCs), natural killer cells (NK) were determined by flow cytometry. After splenocytes were cultured under MMg for 16h, the cell frequency and total numbers of monocytes, macrophages and CD4+Foxp3+T cells were significantly decreased more than 70 %. MMg significantly decreased the cell numbers of CD8+ T cells, B cells and neutrophils in splenocytes. The cell numbers of CD4+T cells and NK cells were unchanged significantly when splenocytes were cultured under MMg compared with controls. However, MMg significantly increased the ratio of mature neutrophils to immature neutrophils in bone marrow and the cell number of DCs in splenocytes. Based on the cell survival ability, monocytes, macrophages and CD4+Foxp3+Treg cells are most sensitive to microgravity; CD4+T cells and NK cells are resistant to microgravity; CD8+T cells and neutrophils are impacted by short term microgravity exposure. Microgravity promoted the maturation of neutrophils and development of DCs in vitro. The present studies offered new insights on the direct effects of MMg on the survival and homeostasis of immune cell subsets.

Development and Function of CD94-Deficient Natural Killer Cells

PubMed Central

Orr, Mark T.; Wu, Jun; Fang, Min; Sigal, Luis J.; Spee, Pieter; Egebjerg, Thomas; Dissen, Erik; Fossum, Sigbjørn; Phillips, Joseph H.; Lanier, Lewis L.

2010-01-01

The CD94 transmembrane-anchored glycoprotein forms disulfide-bonded heterodimers with the NKG2A subunit to form an inhibitory receptor or with the NKG2C or NKG2E subunits to assemble a receptor complex with activating DAP12 signaling proteins. CD94 receptors expressed on human and mouse NK cells and T cells have been proposed to be important in NK cell tolerance to self, play an important role in NK cell development, and contribute to NK cell-mediated immunity to certain infections including human cytomegalovirus. We generated a gene-targeted CD94-deficient mouse to understand the role of CD94 receptors in NK cell biology. CD94-deficient NK cells develop normally and efficiently kill NK cell-susceptible targets. Lack of these CD94 receptors does not alter control of mouse cytomegalovirus, lymphocytic choriomeningitis virus, vaccinia virus, or Listeria monocytogenes. Thus, the expression of CD94 and its associated NKG2A, NKG2C, and NKG2E subunits is dispensable for NK cell development, education, and many NK cell functions. PMID:21151939

Development and function of CD94-deficient natural killer cells.

PubMed

Orr, Mark T; Wu, Jun; Fang, Min; Sigal, Luis J; Spee, Pieter; Egebjerg, Thomas; Dissen, Erik; Fossum, Sigbjørn; Phillips, Joseph H; Lanier, Lewis L

2010-12-03

The CD94 transmembrane-anchored glycoprotein forms disulfide-bonded heterodimers with the NKG2A subunit to form an inhibitory receptor or with the NKG2C or NKG2E subunits to assemble a receptor complex with activating DAP12 signaling proteins. CD94 receptors expressed on human and mouse NK cells and T cells have been proposed to be important in NK cell tolerance to self, play an important role in NK cell development, and contribute to NK cell-mediated immunity to certain infections including human cytomegalovirus. We generated a gene-targeted CD94-deficient mouse to understand the role of CD94 receptors in NK cell biology. CD94-deficient NK cells develop normally and efficiently kill NK cell-susceptible targets. Lack of these CD94 receptors does not alter control of mouse cytomegalovirus, lymphocytic choriomeningitis virus, vaccinia virus, or Listeria monocytogenes. Thus, the expression of CD94 and its associated NKG2A, NKG2C, and NKG2E subunits is dispensable for NK cell development, education, and many NK cell functions.

NK cells are biologic and biochemical targets of 6-mercaptopurine in Crohn's disease patients.

PubMed

Yusung, Susy; McGovern, Dermot; Lin, Lin; Hommes, Daniel; Lagishetty, Venu; Braun, Jonathan

2017-02-01

NK cells, which contribute to immune defense against certain viral infections and neoplasia, are emerging as modifiers of chronic immunologic diseases including transplant rejection and autoimmune diseases. Immunobiology and genetic studies have implicated NK cells as a modifier of Crohn's disease, a condition often treated with thiopurine agents such as 6-mercaptopurine (6-MP). Here, we demonstrate that thiopurines mediate NK cell apoptosis via a caspase 3 and 9 inclusive pathway, and that this process is triggered by thiopurine-mediated inhibition of Rac1. We also show that CD patients in clinical remission maintained on 6-MP have decreased NK cell Rac1 activity, and decreased NK cell numbers in their intestinal biopsies. These observations suggest that thiopurine targeting of NK cells may be a previously unappreciated therapeutic action of these agents in IBD. Copyright © 2016 Elsevier Inc. All rights reserved.

Blocking Blood Supply to Breast Carcinoma With a DNA Vaccine Encoding VEGF Receptor-2

DTIC Science & Technology

2006-03-01

recognize antigens in the form of 8 to 10 amino acid long peptides, presented to T- cell receptors (TCRs) on the cell surface as complexes with major... receptor , and providing tumor- associated antigens , our DNA vaccine can efficiently activate DCs, NK cells , and CTLs, presumably in Peyer’s patches. The... immunoreceptor in immune cell activation and natural killing. Immunity. 2002;17:19-29. (5) Snyder MR, Weyand CM, Goronzy JJ. The double life of NK receptors

NK Cells, Tumor Cell Transition, and Tumor Progression in Solid Malignancies: New Hints for NK-Based Immunotherapy?

PubMed Central

Huergo-Zapico, Leticia; Parodi, Monica; Pedrazzi, Marco; Mingari, Maria Cristina; Sparatore, Bianca; Gonzalez, Segundo; Olive, Daniel; Bottino, Cristina

2016-01-01

Several evidences suggest that NK cells can patrol the body and eliminate tumors in their initial phases but may hardly control established solid tumors. Multiple factors, including the transition of tumor cells towards a proinvasive/prometastatic phenotype, the immunosuppressive effect of the tumor microenvironment, and the tumor structure complexity, may account for limited NK cell efficacy. Several putative mechanisms of NK cell suppression have been defined in these last years; conversely, the cross talk between NK cells and tumor cells undergoing different transitional phases remains poorly explored. Nevertheless, recent in vitro studies and immunohistochemical analyses on tumor biopsies suggest that NK cells could not only kill tumor cells but also influence their evolution. Indeed, NK cells may induce tumor cells to change the expression of HLA-I, PD-L1, or NKG2D-L and modulate their susceptibility to the immune response. Moreover, NK cells may be preferentially located in the borders of tumor masses, where, indeed, tumor cells can undergo Epithelial-to-Mesenchymal Transition (EMT) acquiring prometastatic phenotype. Finally, the recently highlighted role of HMGB1 both in EMT and in amplifying the recruitment of NK cells provides further hints on a possible effect of NK cells on tumor progression and fosters new studies on this issue. PMID:27294158

Herpesvirus Evasion of Natural Killer Cells.

PubMed

De Pelsmaeker, Steffi; Romero, Nicolas; Vitale, Massimo; Favoreel, Herman W

2018-06-01

Natural killer (NK) cells play an important role in the host response against viral infections and cancer development. They are able to kill virus-infected and tumor cells, and they produce different important cytokines that stimulate the antiviral and antitumor adaptive immune response, particularly interferon gamma. NK cells are of particular importance in herpesvirus infections, which is illustrated by systemic and life-threatening herpesvirus disease symptoms in patients with deficiencies in NK cell activity and by the myriad of reports describing herpesvirus NK cell evasion strategies. The latter is particularly obvious for cytomegaloviruses, but increasing evidence indicates that most, if not all, members of the herpesvirus family suppress NK cell activity to some extent. This review discusses the different NK cell evasion strategies described for herpesviruses and how this knowledge may translate to clinical applications. Copyright © 2018 American Society for Microbiology.

Voluntary Running Suppresses Tumor Growth through Epinephrine- and IL-6-Dependent NK Cell Mobilization and Redistribution.

PubMed

Pedersen, Line; Idorn, Manja; Olofsson, Gitte H; Lauenborg, Britt; Nookaew, Intawat; Hansen, Rasmus Hvass; Johannesen, Helle Hjorth; Becker, Jürgen C; Pedersen, Katrine S; Dethlefsen, Christine; Nielsen, Jens; Gehl, Julie; Pedersen, Bente K; Thor Straten, Per; Hojman, Pernille

2016-03-08

Regular exercise reduces the risk of cancer and disease recurrence. Yet the mechanisms behind this protection remain to be elucidated. In this study, tumor-bearing mice randomized to voluntary wheel running showed over 60% reduction in tumor incidence and growth across five different tumor models. Microarray analysis revealed training-induced upregulation of pathways associated with immune function. NK cell infiltration was significantly increased in tumors from running mice, whereas depletion of NK cells enhanced tumor growth and blunted the beneficial effects of exercise. Mechanistic analyses showed that NK cells were mobilized by epinephrine, and blockade of β-adrenergic signaling blunted training-dependent tumor inhibition. Moreover, epinephrine induced a selective mobilization of IL-6-sensitive NK cells, and IL-6-blocking antibodies blunted training-induced tumor suppression, intratumoral NK cell infiltration, and NK cell activation. Together, these results link exercise, epinephrine, and IL-6 to NK cell mobilization and redistribution, and ultimately to control of tumor growth. Copyright © 2016 Elsevier Inc. All rights reserved.

Innate NK cells and macrophages recognize and reject allogeneic nonself in vivo via different mechanisms.

PubMed

Liu, Wentao; Xiao, Xiang; Demirci, Gulcin; Madsen, Joren; Li, Xian C

2012-03-15

Both innate and adaptive immune cells are involved in the allograft response. But how the innate immune cells respond to allotransplants remains poorly defined. In the current study, we examined the roles of NK cells and macrophages in recognizing and rejecting allogeneic cells in vivo. We found that in naive mice NK cells are the primary effector cells in the killing of allogeneic cells via "missing self" recognition. However, in alloantigen-presensitized mice, NK cells are dispensable. Instead, macrophages become alloreactive and readily recognize and reject allogeneic nonself. This effect requires help from activated CD4(+) T cells and involves CD40/CD40L engagement, because blocking CD40/CD40L interactions prevents macrophage-mediated rejection of allogeneic cells. Conversely, actively stimulating CD40 triggers macrophage-mediated rejection in the absence of CD4(+) T cells. Importantly, alloantigen-primed and CD4(+) T cell-helped macrophages (licensed macrophages) exhibit potent regulatory function in vivo in an acute graft-versus-host disease model. Together, our data uncover an important role for macrophages in the alloimmune response and may have important clinical implications.

Variable NK cell receptors and their MHC class I ligands in immunity, reproduction and human evolution.

PubMed

Parham, Peter; Moffett, Ashley

2013-02-01

Natural killer (NK) cells have roles in immunity and reproduction that are controlled by variable receptors that recognize MHC class I molecules. The variable NK cell receptors found in humans are specific to simian primates, in which they have progressively co-evolved with MHC class I molecules. The emergence of the MHC-C gene in hominids drove the evolution of a system of NK cell receptors for MHC-C molecules that is most elaborate in chimpanzees. By contrast, the human system of MHC-C receptors seems to have been subject to different selection pressures that have acted in competition on the immunological and reproductive functions of MHC class I molecules. We suggest that this compromise facilitated the development of the bigger brains that enabled archaic and modern humans to migrate out of Africa and populate other continents.

Echinococcus multilocularis vesicular fluid inhibits activation and proliferation of natural killer cells.

PubMed

Bellanger, Anne-Pauline; Mougey, Valentine; Pallandre, Jean-Rene; Gbaguidi-Haore, Houssein; Godet, Yann; Millon, Laurence

2017-08-25

Alveolar echinococcosis is a severe chronic helminthic disease that mimics slow-growing liver cancer. The immune evasion strategy of Echinococcus multilocularis Leuckart, 1863 remains poorly understood. The aim of this study was to investigate in vitro the impact of E. multilocularis vesicular fluid (Em-VF) on peripheral blood mononuclear cells (PBMC) and on natural killer (NK) cells. PBMC and NK cells were exposed to Em-VF (1 µg/ml) during six days. The effect of Em-VF was assessed on CD69, viability and proliferation, and on and transforming growth factor β (TGF-β), interferon γ (IFN-γ), interleukin 17 (IL-17) and interleukin 10, using flow cytometry and ELISA, respectively. Exposure to Em-VF had no bearing on PBMC's viability, proliferation and expression of CD69. In contrast, higher levels of IL-17 at day three and of TGF-β at day six were observed in PBMC supernatant after exposure to Em-VF (p < 0.05, Wilcoxon signed-rank test). Exposure to Em-VF induced a significant decrease of CD69 expression of NK cells at day three and a significant decrease of proliferation of NK cells at day six (p < 0.05, Wilcoxon signed-rank test). In contrast, NK cells viability and levels of cytokines did not vary significantly over Em-VF stimulation. Exposure to Em-VF had a significant bearing on activation and proliferation of NK cells. NK cells may play an important role in the immune response of the host against E. multilocularis.

Zika Virus Escapes NK Cell Detection by Upregulating Major Histocompatibility Complex Class I Molecules.

PubMed

Glasner, Ariella; Oiknine-Djian, Esther; Weisblum, Yiska; Diab, Mohammad; Panet, Amos; Wolf, Dana G; Mandelboim, Ofer

2017-11-15

NK cells are innate lymphocytes that participate in many immune processes encompassing cancer, bacterial and fungal infection, autoimmunity, and even pregnancy and that specialize in antiviral defense. NK cells express inhibitory and activating receptors and kill their targets when activating signals overpower inhibitory signals. The NK cell inhibitory receptors include a uniquely diverse array of proteins named killer cell immunoglobulin-like receptors (KIRs), the CD94 family, and the leukocyte immunoglobulin-like receptor (LIR) family. The NK cell inhibitory receptors recognize mostly major histocompatibility complex (MHC) class I (MHC-I) proteins. Zika virus has recently emerged as a major threat due to its association with birth defects and its pandemic potential. How Zika virus interacts with the immune system, and especially with NK cells, is unclear. Here we show that Zika virus infection is barely sensed by NK cells, since little or no increase in the expression of activating NK cell ligands was observed following Zika infection. In contrast, we demonstrate that Zika virus infection leads to the upregulation of MHC class I proteins and consequently to the inhibition of NK cell killing. Mechanistically, we show that MHC class I proteins are upregulated via the RIGI-IRF3 pathway and that this upregulation is mediated via beta interferon (IFN-β). Potentially, countering MHC class I upregulation during Zika virus infection could be used as a prophylactic treatment against Zika virus. IMPORTANCE NK cells are innate lymphocytes that recognize and eliminate various pathogens and are known mostly for their role in controlling viral infections. NK cells express inhibitory and activating receptors, and they kill or spare their targets based on the integration of inhibitory and activating signals. Zika virus has recently emerged as a major threat to humans due to its pandemic potential and its association with birth defects. The role of NK cells in Zika virus infection is largely unknown. Here we demonstrate that Zika virus infection is almost undetected by NK cells, as evidenced by the fact that the expression of activating ligands for NK cells is not induced following Zika infection. We identified a mechanism whereby Zika virus sensing via the RIGI-IRF3 pathway resulted in IFN-β-mediated upregulation of MHC-I molecules and inhibition of NK cell activity. Countering MHC class I upregulation and boosting NK cell activity may be employed as prophylactic measures to combat Zika virus infection. Copyright © 2017 American Society for Microbiology.

Zika Virus Escapes NK Cell Detection by Upregulating Major Histocompatibility Complex Class I Molecules

PubMed Central

Glasner, Ariella; Oiknine-Djian, Esther; Weisblum, Yiska; Diab, Mohammad; Panet, Amos; Wolf, Dana G.

2017-01-01

ABSTRACT NK cells are innate lymphocytes that participate in many immune processes encompassing cancer, bacterial and fungal infection, autoimmunity, and even pregnancy and that specialize in antiviral defense. NK cells express inhibitory and activating receptors and kill their targets when activating signals overpower inhibitory signals. The NK cell inhibitory receptors include a uniquely diverse array of proteins named killer cell immunoglobulin-like receptors (KIRs), the CD94 family, and the leukocyte immunoglobulin-like receptor (LIR) family. The NK cell inhibitory receptors recognize mostly major histocompatibility complex (MHC) class I (MHC-I) proteins. Zika virus has recently emerged as a major threat due to its association with birth defects and its pandemic potential. How Zika virus interacts with the immune system, and especially with NK cells, is unclear. Here we show that Zika virus infection is barely sensed by NK cells, since little or no increase in the expression of activating NK cell ligands was observed following Zika infection. In contrast, we demonstrate that Zika virus infection leads to the upregulation of MHC class I proteins and consequently to the inhibition of NK cell killing. Mechanistically, we show that MHC class I proteins are upregulated via the RIGI-IRF3 pathway and that this upregulation is mediated via beta interferon (IFN-β). Potentially, countering MHC class I upregulation during Zika virus infection could be used as a prophylactic treatment against Zika virus. IMPORTANCE NK cells are innate lymphocytes that recognize and eliminate various pathogens and are known mostly for their role in controlling viral infections. NK cells express inhibitory and activating receptors, and they kill or spare their targets based on the integration of inhibitory and activating signals. Zika virus has recently emerged as a major threat to humans due to its pandemic potential and its association with birth defects. The role of NK cells in Zika virus infection is largely unknown. Here we demonstrate that Zika virus infection is almost undetected by NK cells, as evidenced by the fact that the expression of activating ligands for NK cells is not induced following Zika infection. We identified a mechanism whereby Zika virus sensing via the RIGI-IRF3 pathway resulted in IFN-β-mediated upregulation of MHC-I molecules and inhibition of NK cell activity. Countering MHC class I upregulation and boosting NK cell activity may be employed as prophylactic measures to combat Zika virus infection. PMID:28878071

Leukocytosis and natural killer cell function parallel neurobehavioral fatigue induced by 64 hours of sleep deprivation.

PubMed

Dinges, D F; Douglas, S D; Zaugg, L; Campbell, D E; McMann, J M; Whitehouse, W G; Orne, E C; Kapoor, S C; Icaza, E; Orne, M T

1994-05-01

The hypothesis that sleep deprivation depresses immune function was tested in 20 adults, selected on the basis of their normal blood chemistry, monitored in a laboratory for 7 d, and kept awake for 64 h. At 2200 h each day measurements were taken of total leukocytes (WBC), monocytes, granulocytes, lymphocytes, eosinophils, erythrocytes (RBC), B and T lymphocyte subsets, activated T cells, and natural killer (NK) subpopulations (CD56/CD8 dual-positive cells, CD16-positive cells, CD57-positive cells). Functional tests included NK cytotoxicity, lymphocyte stimulation with mitogens, and DNA analysis of cell cycle. Sleep loss was associated with leukocytosis and increased NK cell activity. At the maximum sleep deprivation, increases were observed in counts of WBC, granulocytes, monocytes, NK activity, and the proportion of lymphocytes in the S phase of the cell cycle. Changes in monocyte counts correlated with changes in other immune parameters. Counts of CD4, CD16, CD56, and CD57 lymphocytes declined after one night without sleep, whereas CD56 and CD57 counts increased after two nights. No changes were observed in other lymphocyte counts, in proliferative responses to mitogens, or in plasma levels of cortisol or adrenocorticotropin hormone. The physiologic leukocytosis and NK activity increases during deprivation were eliminated by recovery sleep in a manner parallel to neurobehavioral function, suggesting that the immune alterations may be associated with biological pressure for sleep.

Leukocytosis and natural killer cell function parallel neurobehavioral fatigue induced by 64 hours of sleep deprivation.

PubMed Central

Dinges, D F; Douglas, S D; Zaugg, L; Campbell, D E; McMann, J M; Whitehouse, W G; Orne, E C; Kapoor, S C; Icaza, E; Orne, M T

1994-01-01

The hypothesis that sleep deprivation depresses immune function was tested in 20 adults, selected on the basis of their normal blood chemistry, monitored in a laboratory for 7 d, and kept awake for 64 h. At 2200 h each day measurements were taken of total leukocytes (WBC), monocytes, granulocytes, lymphocytes, eosinophils, erythrocytes (RBC), B and T lymphocyte subsets, activated T cells, and natural killer (NK) subpopulations (CD56/CD8 dual-positive cells, CD16-positive cells, CD57-positive cells). Functional tests included NK cytotoxicity, lymphocyte stimulation with mitogens, and DNA analysis of cell cycle. Sleep loss was associated with leukocytosis and increased NK cell activity. At the maximum sleep deprivation, increases were observed in counts of WBC, granulocytes, monocytes, NK activity, and the proportion of lymphocytes in the S phase of the cell cycle. Changes in monocyte counts correlated with changes in other immune parameters. Counts of CD4, CD16, CD56, and CD57 lymphocytes declined after one night without sleep, whereas CD56 and CD57 counts increased after two nights. No changes were observed in other lymphocyte counts, in proliferative responses to mitogens, or in plasma levels of cortisol or adrenocorticotropin hormone. The physiologic leukocytosis and NK activity increases during deprivation were eliminated by recovery sleep in a manner parallel to neurobehavioral function, suggesting that the immune alterations may be associated with biological pressure for sleep. PMID:7910171

Monocytes Play an IL-12-Dependent Crucial Role in Driving Cord Blood NK Cells to Produce IFN-g in Response to Trypanosoma cruzi

PubMed Central

Guilmot, Aline; Bosse, Julie; Carlier, Yves; Truyens, Carine

2013-01-01

We previously reported that foetuses congenitally infected with Trypanosoma cruzi, the agent of Chagas disease, mount an adult-like parasite-specific CD8+ T-cell response, producing IFN-g, and present an altered NK cell phenotype, possibly reflecting a post-activation state supported by the ability of the parasite to trigger IFN-g synthesis by NK cells in vitro. We here extended our knowledge on NK cell activation by the parasite. We compared the ability of T. cruzi to activate cord blood and adult NK cells from healthy individuals. Twenty-four hours co-culture of cord blood mononuclear cells with T. cruzi trypomastigotes and IL-15 induced high accumulation of IFN-g transcripts and IFN-g release. TNF-a, but not IL-10, was also produced. This was associated with up-regulation of CD69 and CD54, and down-regulation of CD62L on NK cells. The CD56bright NK cell subset was the major IFN-g responding subset (up to 70% IFN-g-positive cells), while CD56dim NK cells produced IFN-g to a lesser extent. The response points to a synergy between parasites and IL-15. The neonatal response, observed in all newborns, remained however slightly inferior to that of adults. Activation of IL-15-sensitized cord blood NK cells by the parasite required contacts with live/intact parasites. In addition, it depended on the engagement of TLR-2 and 4 and involved IL-12 and cross-talk with monocytes but not with myeloid dendritic cells, as shown by the use of neutralizing antibodies and cell depletion. This work highlights the ability of T. cruzi to trigger a robust IFN-g response by IL-15-sensitized human neonatal NK cells and the important role of monocytes in it, which might perhaps partially compensate for the neonatal defects of DCs. It suggests that monocyte- and IL-12- dependent IFN-g release by NK cells is a potentially important innate immune response pathway allowing T. cruzi to favour a type 1 immune response in neonates. PMID:23819002

Effect of kumquat (Fortunella crassifolia) pericarp on natural killer cell activity in vitro and in vivo.

PubMed

Nagahama, Kiyoko; Eto, Nozomu; Shimojo, Tomofumi; Kondoh, Tomomi; Nakahara, Keiko; Sakakibara, Yoichi; Fukui, Keiichi; Suiko, Masahito

2015-01-01

Natural killer (NK) cells play a key role in innate immune defense against infectious disease and cancer. A reduction of NK activity is likely to be associated with increased risk of these types of disease. In this study, we investigate the activation potential of kumquat pericarp acetone fraction (KP-AF) on NK cells. It is shown to significantly increase IFN-γ production and NK cytotoxic activity in human KHYG-1 NK cells. Moreover, oral administration of KP-AF significantly improves both suppressed plasma IFN-γ levels and NK cytotoxic activity per splenocyte in restraint-stressed mice. These results indicate that raw kumquat pericarp activates NK cells in vitro and in vivo. To identify the active constituents, we also examined IFN-γ production on KHYG-1 cells by the predicted active components. Only β-cryptoxanthin increased IFN-γ production, suggesting that NK cell activation effects of KP-AF may be caused by carotenoids such as β-cryptoxanthin.

Irradiated and activated autologous PBMCs induce expansion of highly cytotoxic human NK cells in vitro.

PubMed

Ahn, Yong-Oon; Kim, Saerom; Kim, Tae Min; Song, Eun Young; Park, Myoung Hee; Heo, Dae Seog

2013-09-01

Adoptive cell transfer of ex vivo-activated natural killer (NK) cells is a promising therapy for cancer treatment. Because of inhibitory signaling through killer immunoglobulin-like receptor (KIR)-KIR ligands, KIR-mismatched allogeneic NK cell transfer is considered to be a more effective strategy than is autologous transfer. However, purified NK cells do not expand well enough in vitro with good manufacturing practice-compliant components for clinical use. Some investigators have developed selective expansion of NK cells from peripheral blood mononuclear cells, but these cells have the risk of graft-versus-host disease in allogeneic settings because of T cells contamination. In this study, we developed a novel method for NK cell activation and expansion. Using only good manufacturing practice-compliant components and autologous feeder cells, once purified NK cells were effectively expanded (2500-fold at day 17). The expanded cells were highly purified NK cells, and the use of these cells is suitable for allogeneic transfer without the risk of graft-versus-host disease induction. Importantly, the expanded NK cells also showed enhanced cytotoxicity compared with NK cells conventionally expanded by recombinant human interleukin 2. Finally, induction of NKG2D ligand expression on feeder cells implies that the NKG2D-NKG2DL interaction may play a role in NK cell expansion. In conclusion, this method can be used to obtain NK cells for more successful allogeneic NK cell adoptive transfer for use in antitumor immune therapy.

Prospective study of the evolution of blood lymphoid immune parameters during dacarbazine chemotherapy in metastatic and locally advanced melanoma patients.

PubMed

Mignot, Grégoire; Hervieu, Alice; Vabres, Pierre; Dalac, Sophie; Jeudy, Geraldine; Bel, Blandine; Apetoh, Lionel; Ghiringhelli, François

2014-01-01

The importance of immune responses in the control of melanoma growth is well known. However, the implication of these antitumor immune responses in the efficacy of dacarbazine, a cytotoxic drug classically used in the treatment of melanoma, remains poorly understood in humans. In this prospective observational study, we performed an immunomonitoring of eleven metastatic or locally advanced patients treated with dacarbazine as a first line of treatment. We assessed by flow cytometry lymphoid populations and their activation state; we also isolated NK cells to perform in vitro cytotoxicity tests. We found that chemotherapy induces lymphopenia and that a significantly higher numbers of naïve CD4+ T cells and lower proportion of Treg before chemotherapy are associated with disease control after dacarbazine treatment. Interestingly, NK cell cytotoxicity against dacarbazine-pretreated melanoma cells is only observed in NK cells from patients who achieved disease control. Together, our data pinpoint that some immune factors could help to predict the response of melanoma patients to dacarbazine. Future larger scale studies are warranted to test their validity as prediction markers.

Role of adaptive and innate immune cells in chronic fatigue syndrome/myalgic encephalomyelitis.

PubMed

Brenu, Ekua Weba; Huth, Teilah K; Hardcastle, Sharni L; Fuller, Kirsty; Kaur, Manprit; Johnston, Samantha; Ramos, Sandra B; Staines, Don R; Marshall-Gradisnik, Sonya M

2014-04-01

Perturbations in immune processes are a hallmark of a number of autoimmune and inflammatory disorders. Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is an inflammatory disorder with possible autoimmune correlates, characterized by reduced NK cell activity, elevations in regulatory T cells (Tregs) and dysregulation in cytokine levels. The purpose of this article is to examine innate and adaptive immune cell phenotypes and functional characteristics that have not been previously examined in CFS/ME patients. Thirty patients with CFS/ME and 25 non-fatigued controls were recruited for this study. Whole blood samples were collected from all participants for the assessment of cell phenotypes, functional properties, receptors, adhesion molecules, antigens and intracellular proteins using flow cytometric protocols. The cells investigated included NK cells, dendritic cells, neutrophils, B cells, T cells, γδT cells and Tregs. Significant changes were observed in B-cell subsets, Tregs, CD4(+)CD73(+)CD39(+) T cells, cytotoxic activity, granzyme B, neutrophil antigens, TNF-α and IFN-γ in the CFS/ME patients in comparison with the non-fatigued controls. Alterations in B cells, Tregs, NK cells and neutrophils suggest significant impairments in immune regulation in CFS/ME and these may have similarities to a number of autoimmune disorders.

SHIP1 intrinsically regulates NK cell signaling and education, resulting in tolerance of an MHC class I-mismatched bone marrow graft in mice.

PubMed

Gumbleton, Matthew; Vivier, Eric; Kerr, William G

2015-03-15

NK cells are an important component of host immune defense against malignancy and infection. NK cells are educated by MHC class I ligands to ensure self-tolerance while also promoting lytic competency against altered self and damaged self targets. However, the intracellular molecular events that culminate in tolerance and functional competency of educated NK cells remain undefined. Mice with germline deficiency in SHIP1 were shown to have a defective NK cell compartment. However, SHIP1 is expressed in all hematopoietic lineages, and consequently several hematolymphoid phenotypes have already been identified in certain cell types that are the result of SHIP1 deficiency in cells in separate and distinct lineages, that is, cell-extrinsic phenotypes. Thus, it was previously impossible to determine the NK cell-intrinsic role of SHIP1. In the present study, through the creation of an NK cell-specific deletion mouse model of SHIP1, we show that SHIP1 plays a profound NK lineage-intrinsic role in NK cell homeostasis, development, education, and cytokine production. Moreover, we show SHIP1 expression by NK cells is required for in vivo-mismatched bone marrow allograft rejection as well as for NK memory responses to hapten. Copyright © 2015 by The American Association of Immunologists, Inc.

Circulating T-Cell Subsets, Monocytes, and Natural Killer Cells in Peripartum Cardiomyopathy: Results From the Multicenter IPAC Study.

PubMed

McTiernan, Charles F; Morel, Penelope; Cooper, Leslie T; Rajagopalan, Navin; Thohan, Vinay; Zucker, Mark; Boehmer, John; Bozkurt, Biykem; Mather, Paul; Thornton, John; Ghali, Jalal K; Hanley-Yanez, Karen; Fett, James; Halder, Indrani; McNamara, Dennis M

2018-01-01

The aim of this work was to evaluate the hypothesis that the distribution of circulating immune cell subsets, or their activation state, is significantly different between peripartum cardiomyopathy (PPCM) and healthy postpartum (HP) women. PPCM is a major cause of maternal morbidity and mortality, and an immune-mediated etiology has been hypothesized. Cellular immunity, altered in pregnancy and the peripartum period, has been proposed to play a role in PPCM pathogenesis. The Investigation of Pregnancy-Associated Cardiomyopathy (IPAC) study enrolled 100 women presenting with a left ventricular ejection fraction of <0.45 within 2 months of delivery. Peripheral T-cell subsets, natural killer (NK) cells, and cellular activation markers were assessed by flow cytometry in PPCM women early (<6 wk), 2 months, and 6 months postpartum and compared with those of HP women and women with non-pregnancy-associated recent-onset cardiomyopathy (ROCM). Entry NK cell levels (CD3-CD56+CD16+; reported as % of CD3- cells) were significantly (P < .0003) reduced in PPCM (6.6 ± 4.9% of CD3- cells) compared to HP (11.9 ± 5%). Of T-cell subtypes, CD3+CD4-CD8-CD38+ cells differed significantly (P < .004) between PPCM (24.5 ± 12.5% of CD3+CD4-CD8- cells) and HP (12.5 ± 6.4%). PPCM patients demonstrated a rapid recovery of NK and CD3+CD4-CD8-CD38+ cell levels. However, black women had a delayed recovery of NK cells. A similar reduction of NK cells was observed in women with ROCM. Compared with HP control women, early postpartum PPCM women show significantly reduced NK cells, and higher CD3+CD4-CD8-CD38+ cells, which both normalize over time postpartum. The mechanistic role of NK cells and "double negative" (CD4-CD8-) T regulatory cells in PPCM requires further investigation. Copyright © 2017 Elsevier Inc. All rights reserved.

Natural killer cell dysfunction in hepatocellular carcinoma and NK cell-based immunotherapy

PubMed Central

Sun, Cheng; Sun, Hao-yu; Xiao, Wei-hua; Zhang, Cai; Tian, Zhi-gang

2015-01-01

The mechanisms linking hepatitis B virus (HBV) and hepatitis C virus (HCV) infection to hepatocellular carcinoma (HCC) remain largely unknown. Natural killer (NK) cells account for 25%–50% of the total number of liver lymphocytes, suggesting that NK cells play an important role in liver immunity. The number of NK cells in the blood and tumor tissues of HCC patients is positively correlated with their survival and prognosis. Furthermore, a group of NK cell-associated genes in HCC tissues is positively associated with the prolonged survival. These facts suggest that NK cells and HCC progression are strongly associated. In this review, we describe the abnormal NK cells and their functional impairment in patients with chronic HBV and HCV infection, which contribute to the progression of HCC. Then, we summarize the association of NK cells with HCC based on the abnormalities in the numbers and phenotypes of blood and liver NK cells in HCC patients. In particular, the exhaustion of NK cells that represents lower cytotoxicity and impaired cytokine production may serve as a predictor for the occurrence of HCC. Finally, we present the current achievements in NK cell immunotherapy conducted in mouse models of liver cancer and in clinical trials, highlighting how chemoimmunotherapy, NK cell transfer, gene therapy, cytokine therapy and mAb therapy improve NK cell function in HCC treatment. It is conceivable that NK cell-based anti-HCC therapeutic strategies alone or in combination with other therapies will be great promise for HCC treatment. PMID:26073325

Induction of potent NK cell-dependent anti-myeloma cytotoxic T cells in response to combined mapatumumab and bortezomib.

PubMed

Neeson, Paul J; Hsu, Andy K; Chen, Yin R; Halse, Heloise M; Loh, Joanna; Cordy, Reece; Fielding, Kate; Davis, Joanne; Noske, Josh; Davenport, Alex J; Lindqvist-Gigg, Camilla A; Humphreys, Robin; Tai, Tsin; Prince, H Miles; Trapani, Joseph A; Smyth, Mark J; Ritchie, David S

2015-09-01

There is increasing evidence that some cancer therapies can promote tumor immunogenicity to boost the endogenous antitumor immune response. In this study, we used the novel combination of agonistic anti-TRAIL-R1 antibody (mapatumumab, Mapa) with low dose bortezomib (LDB) for this purpose. The combination induced profound myeloma cell apoptosis, greatly enhanced the uptake of myeloma cell apoptotic bodies by dendritic cell (DC) and induced anti-myeloma cytotoxicity by both CD8 + T cells and NK cells. Cytotoxic lymphocyte expansion was detected within 24 h of commencing therapy and was maximized when myeloma-pulsed DC were co-treated with low dose bortezomib and mapatumumab (LDB+Mapa) in the presence of NK cells. This study shows that Mapa has two distinct but connected modes of action against multiple myeloma (MM). First, when combined with LDB, Mapa produced powerful myeloma cell apoptosis; secondly, it promoted DC priming and an NK cell-mediated expansion of anti-myeloma cytotoxic lymphocyte (CTL). Overall, this study indicates that Mapa can be used to drive potent anti-MM immune responses.

Induction of potent NK cell-dependent anti-myeloma cytotoxic T cells in response to combined mapatumumab and bortezomib

PubMed Central

Neeson, Paul J; Hsu, Andy K; Chen, Yin R; Halse, Heloise M; Loh, Joanna; Cordy, Reece; Fielding, Kate; Davis, Joanne; Noske, Josh; Davenport, Alex J; Lindqvist-Gigg, Camilla A; Humphreys, Robin; Tai, Tsin; Prince, H Miles; Trapani, Joseph A; Smyth, Mark J; Ritchie, David S

2015-01-01

There is increasing evidence that some cancer therapies can promote tumor immunogenicity to boost the endogenous antitumor immune response. In this study, we used the novel combination of agonistic anti-TRAIL-R1 antibody (mapatumumab, Mapa) with low dose bortezomib (LDB) for this purpose. The combination induced profound myeloma cell apoptosis, greatly enhanced the uptake of myeloma cell apoptotic bodies by dendritic cell (DC) and induced anti-myeloma cytotoxicity by both CD8+ T cells and NK cells. Cytotoxic lymphocyte expansion was detected within 24 h of commencing therapy and was maximized when myeloma-pulsed DC were co-treated with low dose bortezomib and mapatumumab (LDB+Mapa) in the presence of NK cells. This study shows that Mapa has two distinct but connected modes of action against multiple myeloma (MM). First, when combined with LDB, Mapa produced powerful myeloma cell apoptosis; secondly, it promoted DC priming and an NK cell-mediated expansion of anti-myeloma cytotoxic lymphocyte (CTL). Overall, this study indicates that Mapa can be used to drive potent anti-MM immune responses. PMID:26405606

Adiponectin deficiency suppresses lymphoma growth in mice by modulating NK cells, CD8 T cells, and myeloid-derived suppressor cells.

PubMed

Han, Sora; Jeong, Ae Lee; Lee, Sunyi; Park, Jeong Su; Kim, Kwang Dong; Choi, Inpyo; Yoon, Suk Ran; Lee, Myung Sok; Lim, Jong-Seok; Han, Seung Hyun; Yoon, Do Young; Yang, Young

2013-05-01

Previously, we found that adiponectin (APN) suppresses IL-2-induced NK cell activation by downregulating the expression of the IFN-γ-inducible TNF-related apoptosis-inducing ligand and Fas ligand. Although the antitumor function of APN has been reported in several types of solid tumors, with few controversial results, no lymphoma studies have been conducted. In this study, we assessed the role of APN in immune cell function, including NK cells, CTLs, and myeloid-derived suppressor cells, in EL4 and B16F10 tumor-bearing APN knockout (KO) mice. We observed attenuated EL4 growth in the APNKO mice. Increased numbers of splenic NK cells and splenic CTLs were identified under naive conditions and EL4-challenged conditions, respectively. In APNKO mice, splenic NK cells showed enhanced cytotoxicity with and without IL-2 stimulation. Additionally, there were decreased levels of myeloid-derived suppressor cell accumulation in the EL4-bearing APNKO mice. Enforced MHC class I expression on B16F10 cells led to attenuated growth of these tumors in APNKO mice. Thus, our results suggest that EL4 regression in APNKO mice is not only due to an enhanced antitumor immune response but also to a high level of MHC class I expression.

Calorie Restriction Attenuates Terminal Differentiation of Immune Cells.

PubMed

White, Matthew J; Beaver, Charlotte M; Goodier, Martin R; Bottomley, Christian; Nielsen, Carolyn M; Wolf, Asia-Sophia F M; Boldrin, Luisa; Whitmore, Charlotte; Morgan, Jennifer; Pearce, Daniel J; Riley, Eleanor M

2016-01-01

Immune senescence is a natural consequence of aging and may contribute to frailty and loss of homeostasis in later life. Calorie restriction increases healthy life-span in C57BL/6J (but not DBA/2J) mice, but whether this is related to preservation of immune function, and how it interacts with aging, is unclear. We compared phenotypic and functional characteristics of natural killer (NK) cells and T cells, across the lifespan, of calorie-restricted (CR) and control C57BL/6 and DBA/2 mice. Calorie restriction preserves a naïve T cell phenotype and an immature NK cell phenotype as mice age. The splenic T cell populations of CR mice had higher proportions of CD11a - CD44 lo cells, lower expression of TRAIL, KLRG1, and CXCR3, and higher expression of CD127, compared to control mice. Similarly, splenic NK cells from CR mice had higher proportions of less differentiated CD11b - CD27 + cells and correspondingly lower proportions of highly differentiated CD11b + CD27 - NK cells. Within each of these subsets, cells from CR mice had higher expression of CD127, CD25, TRAIL, NKG2A/C/E, and CXCR3 and lower expression of KLRG1 and Ly49 receptors compared to controls. The effects of calorie restriction on lymphoid cell populations in lung, liver, and lymph nodes were identical to those seen in the spleen, indicating that this is a system-wide effect. The impact of calorie restriction on NK cell and T cell maturation is much more profound than the effect of aging and, indeed, calorie restriction attenuates these age-associated changes. Importantly, the effects of calorie restriction on lymphocyte maturation were more marked in C57BL/6 than in DBA/2J mice indicating that delayed lymphocyte maturation correlates with extended lifespan. These findings have implications for understanding the interaction between nutritional status, immunity, and healthy lifespan in aging populations.

Imatinib and Nilotinib Off-Target Effects on Human NK Cells, Monocytes, and M2 Macrophages.

PubMed

Bellora, Francesca; Dondero, Alessandra; Corrias, Maria Valeria; Casu, Beatrice; Regis, Stefano; Caliendo, Fabio; Moretta, Alessandro; Cazzola, Mario; Elena, Chiara; Vinti, Luciana; Locatelli, Franco; Bottino, Cristina; Castriconi, Roberta

2017-08-15

Tyrosine kinase inhibitors (TKIs) are used in the clinical management of hematological neoplasms. Moreover, in solid tumors such as stage 4 neuroblastomas (NB), imatinib showed benefits that might depend on both on-target and immunological off-target effects. We investigated the effects of imatinib and nilotinib on human NK cells, monocytes, and macrophages. High numbers of monocytes died upon exposure to TKI concentrations similar to those achieved in patients. Conversely, NK cells were highly resistant to the TKI cytotoxic effect, were properly activated by immunostimulatory cytokines, and degranulated in the presence of NB cells. In NB, neither drug reduced the expression of ligands for activating NK receptors or upregulated that of HLA class I, B7-H3, PD-L1, and PD-L2, molecules that might limit NK cell function. Interestingly, TKIs modulated the chemokine receptor repertoire of immune cells. Acting at the transcriptional level, they increased the surface expression of CXCR4, an effect observed also in NK cells and monocytes of patients receiving imatinib for chronic myeloid leukemia. Moreover, TKIs reduced the expression of CXCR3 (in NK cells) and CCR1 (in monocytes). Monocytes also decreased the expression of M-CSFR, and low numbers of cells underwent differentiation toward macrophages. M0 and M2 macrophages were highly resistant to TKIs and maintained their phenotypic and functional characteristics. Importantly, also in the presence of TKIs, the M2 immunosuppressive polarization was reverted by TLR engagement, and M1-oriented macrophages fully activated autologous NK cells. Our results contribute to better interpreting the off-target efficacy of TKIs in tumors and to envisaging strategies aimed at facilitating antitumor immune responses. Copyright © 2017 by The American Association of Immunologists, Inc.

Natural killer cells and regulatory T cells in early pregnancy loss

PubMed Central

SHARMA, SURENDRA

2015-01-01

Survival of the allogeneic embryo in the uterus depends on the maintenance of immune tolerance at the maternal-fetal interface. The pregnant uterus is replete with activated maternal immune cells. How this immune tolerance is acquired and maintained has been a topic of intense investigation. The key immune cells that predominantly populate the pregnant uterus are natural killer (NK) cells. In normal pregnancy, these cells are not killers, but rather provide a microenvironment that is pregnancy compatible and supports healthy placentation. In placental mammals, an array of highly orchestrated immune elements to support successful pregnancy outcome has been incorporated. This includes active cooperation between maternal immune cells, particularly NK cells, and trophoblast cells. This intricate process is required for placentation, immune regulation and to remodel the blood supply to the fetus. During the past decade, various types of maternal immune cells have been thought to be involved in cross-talk with trophoblasts and in programming immune tolerance. RegulatoryT cells (Tregs) have attracted a great deal of attention in promoting implantation and immune tolerance beyond implantation. However, what has not been fully addressed is how this immune-trophoblast axis breaks down during adverse pregnancy outcomes, particularly early pregnancy loss, and in response to unscheduled inflammation. Intense research efforts have begun to shed light on the roles of NK cells and Tregs in early pregnancy loss, although much remains to be unraveled in order to fully characterize the mechanisms underlying their detrimental activity. An increased understanding of host-environment interactions that lead to the cytotoxic phenotype of these otherwise pregnancy compatible maternal immune cells is important for prediction, prevention and treatment of pregnancy maladies, particularly recurrent pregnancy loss. In this review, we discuss relevant information from experimental and human models that may explain the pregnancy disrupting roles of these pivotal sentinel cells at the maternal-fetal interface. PMID:25023688

Identification of a subset of human natural killer cells expressing high levels of programmed death 1: A phenotypic and functional characterization.

PubMed

Pesce, Silvia; Greppi, Marco; Tabellini, Giovanna; Rampinelli, Fabio; Parolini, Silvia; Olive, Daniel; Moretta, Lorenzo; Moretta, Alessandro; Marcenaro, Emanuela

2017-01-01

Programmed death 1 (PD-1) is an immunologic checkpoint that limits immune responses by delivering potent inhibitory signals to T cells on interaction with specific ligands expressed on tumor/virus-infected cells, thus contributing to immune escape mechanisms. Therapeutic PD-1 blockade has been shown to mediate tumor eradication with impressive clinical results. Little is known about the expression/function of PD-1 on human natural killer (NK) cells. We sought to clarify whether human NK cells can express PD-1 and analyze their phenotypic/functional features. We performed multiparametric cytofluorimetric analysis of PD-1 + NK cells and their functional characterization using degranulation, cytokine production, and proliferation assays. We provide unequivocal evidence that PD-1 is highly expressed (PD-1 bright ) on an NK cell subset detectable in the peripheral blood of approximately one fourth of healthy subjects. These donors are always serologically positive for human cytomegalovirus. PD-1 is expressed by CD56 dim but not CD56 bright NK cells and is confined to fully mature NK cells characterized by the NKG2A - KIR + CD57 + phenotype. Proportions of PD-1 bright NK cells were higher in the ascites of a cohort of patients with ovarian carcinoma, suggesting their possible induction/expansion in tumor environments. Functional analysis revealed a reduced proliferative capability in response to cytokines, low degranulation, and impaired cytokine production on interaction with tumor targets. We have identified and characterized a novel subpopulation of human NK cells expressing high levels of PD-1. These cells have the phenotypic characteristics of fully mature NK cells and are increased in patients with ovarian carcinoma. They display low proliferative responses and impaired antitumor activity that can be partially restored by antibody-mediated disruption of PD-1/programmed death ligand interaction. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Targeting the Epidermal Growth Factor Receptor Can Counteract the Inhibition of Natural Killer Cell Function Exerted by Colorectal Tumor-Associated Fibroblasts

PubMed Central

Costa, Delfina; Venè, Roberta; Benelli, Roberto; Romairone, Emanuele; Scabini, Stefano; Catellani, Silvia; Rebesco, Barbara; Mastracci, Luca; Grillo, Federica; Minghelli, Simona; Loiacono, Fabrizio; Zocchi, Maria Raffaella; Poggi, Alessandro

2018-01-01

Mesenchymal stromal cells (MSC) present in the tumor microenvironment [usually named tumor-associated fibroblasts (TAF)] can exert immunosuppressive effects on T and natural killer (NK) lymphocytes, favoring tumor immune escape. We have analyzed this mechanism in colorectal carcinoma (CRC) and found that co-culture of NK cells with TAF can prevent the IL-2-mediated NKG2D upregulation. This leads to the impairment of NKG2D-mediated recognition of CRC cells, sparing the NK cell activation through DNAM1 or FcγRIIIA (CD16). In situ, TAF express detectable levels of epidermal growth factor receptor (EGFR); thus, the therapeutic anti-EGFR humanized antibody cetuximab can trigger the antibody-dependent cellular cytotoxicity of TAF, through the engagement of FcγRIIIA on NK cells. Importantly, in the tumor, we found a lymphoid infiltrate containing NKp46+CD3− NK cells, enriched in CD16+ cells. This population, sorted and cultured with IL-2, could be triggered via CD16 and via NKG2D. Of note, ex vivo NKp46+CD3− cells were able to kill autologous TAF; in vivo, this might represent a control mechanism to reduce TAF-mediated regulatory effect on NK cell function. Altogether, these findings suggest that MSC from the neoplastic mucosa (TAF) of CRC patients can downregulate the immune cell recognition of CRC tumor cells. This immunosuppression can be relieved by the anti-EGFR antibody used in CRC immunotherapy. PMID:29910806

Chronic alcohol consumption enhances iNKT cell maturation and activation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Hui, E-mail: hzhang@wsu.edu; Zhang, Faya; Zhu, Zhaohui

Alcohol consumption exhibits diverse effects on different types of immune cells. NKT cells are a unique T cell population and play important immunoregulatory roles in different types of immune responses. The effects of chronic alcohol consumption on NKT cells remain to be elucidated. Using a mouse model of chronic alcohol consumption, we found that alcohol increases the percentage of NKT cells, especially iNKT cells in the thymus and liver, but not in the spleen or blood. Alcohol consumption decreases the percentage of NK1.1{sup −} iNKT cells in the total iNKT cell population in all of the tissues and organs examined.more » In the thymus, alcohol consumption increases the number of NK1.1{sup +}CD44{sup hi} mature iNKT cells but does not alter the number of NK1.1{sup −} immature iNKT cells. A BrdU incorporation assay shows that alcohol consumption increases the proliferation of thymic NK1.1{sup −} iNKT cells, especially the NK1.1{sup −}CD44{sup lo} Stage I iNKT cells. The percentage of NKG2A{sup +} iNKT cells increases in all of the tissues and organs examined; whereas CXCR3{sup +} iNKT cells only increases in the thymus of alcohol-consuming mice. Chronic alcohol consumption increases the percentage of IFN-γ-producing iNKT cells and increases the blood concentration of IFN-γ and IL-12 after in vivo α-galactosylceramide (αGalCer) stimulation. Consistent with the increased cytokine production, the in vivo activation of iNKT cells also enhances the activation of dendritic cells (DC) and NK, B, and T cells in the alcohol-consuming mice. Taken together the data indicate that chronic alcohol consumption enhances iNKT cell maturation and activation, which favors the Th1 immune response. - Highlights: • Chronic alcohol consumption increases iNKT cells in the thymus and liver • Chronic alcohol consumption enhances thymic Stage I iNKT cell proliferation • Chronic alcohol consumption enhances iNKT cell maturation in thymus and periphery • Chronic alcohol consumption induces Th1 immune response upon iNKT cell in vivo activation.« less

Regulation of Mouse NK Cell Development and Function by Cytokines

PubMed Central

Marçais, Antoine; Viel, Sébastien; Grau, Morgan; Henry, Thomas; Marvel, Jacqueline; Walzer, Thierry

2013-01-01

Natural Killer (NK) cells are innate lymphocytes with an important role in the early defense against intracellular pathogens and against tumors. Like other immune cells, almost every aspects of their biology are regulated by cytokines. Interleukin (IL)-15 is pivotal for their development, homeostasis, and activation. Moreover, numerous other activating or inhibitory cytokines such as IL-2, IL-4, IL-7, IL-10, IL-12, IL-18, IL-21, Transforming growth factor-β (TGFβ) and type I interferons regulate their activation and their effector functions at different stages of the immune response. In this review we summarize the current understanding on the effect of these different cytokines on NK cell development, homeostasis, and functions during steady-state or upon infection by different pathogens. We try to delineate the cellular sources of these cytokines, the intracellular pathways they trigger and the transcription factors they regulate. We describe the known synergies or antagonisms between different cytokines and highlight outstanding questions in this field of investigation. Finally, we discuss how a better knowledge of cytokine action on NK cells could help improve strategies to manipulate NK cells in different clinical situations. PMID:24376448

Increased level and interferon-γ production of circulating natural killer cells in patients with scrub typhus.

PubMed

Kang, Seung-Ji; Jin, Hye-Mi; Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung; Park, Yong-Wook

2017-07-01

Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients.

Increased level and interferon-γ production of circulating natural killer cells in patients with scrub typhus

PubMed Central

Cho, Young-Nan; Kim, Seong Eun; Kim, Uh Jin; Park, Kyung-Hwa; Jang, Hee-Chang; Jung, Sook-In; Kee, Seung-Jung

2017-01-01

Background Natural killer (NK) cells are essential immune cells against several pathogens. Not much is known regarding the roll of NK cells in Orientia tsutsugamushi infection. Thus, this study aims to determine the level, function, and clinical relevance of NK cells in patients with scrub typhus. Methodology/Principal findings This study enrolled fifty-six scrub typhus patients and 56 health controls (HCs). The patients were divided into subgroups according to their disease severity. A flow cytometry measured NK cell level and function in peripheral blood. Circulating NK cell levels and CD69 expressions were significantly increased in scrub typhus patients. Increased NK cell levels reflected disease severity. In scrub typhus patients, tests showed their NK cells produced higher amounts of interferon (IFN)-γ after stimulation with interleukin (IL)-12 and IL-18 relative to those of HCs. Meanwhile, between scrub typhus patients and HCs, the cytotoxicity and degranulation of NK cells against K562 were comparable. CD69 expressions were recovered to the normal levels in the remission phase. Conclusions This study shows that circulating NK cells are activated and numerically increased, and they produced more IFN-γ in scrub typhus patients. PMID:28750012

Chemotherapy changes cytotoxic activity of NK-cells in cancer patients

NASA Astrophysics Data System (ADS)

Stakheyeva, M.; Yunusova, N.; Patysheva, M.; Mitrofanova, I. V.; Faltin, V.; Tuzikov, S.; Slonimskaya, E.

2017-09-01

In recent years, it has been shown that under certain conditions cytostatic agents (chemotherapy and radiotherapy) can restore the functioning of the immune system impaired by malignancy burden. The modifications of biological properties by cytostatics acting make cancer cells visible for the immune system recognition and elimination. Eighteen patients diagnosed with primary local breast (8) and gastric (10) cancer between 2014 and 2016 were enrolled in the investigation. The phenotypic features of NK were assessed by flow cytometry using mAb (BD Pharmingen) against CD45 (common leukocyte antigen) and CD56 (NK-marker) for surface staining, CD107a (LAMP-1), Perforin (PF) and Gransime B (GB) for intracellular staining. We examined NK populations in the peripheral blood of cancer patients before treatment and in 5 days after second course of NACT. We found that NK populations produced PF in cancer patents, which were absent before treatment, increased after NACT. Their emergence can be associated with the immunoactivating effects of chemotherapy, realized by the modification of tumor cells or elimination of immunosuppressive cells.

The use of microRNA by human viruses: lessons from NK cells and HCMV infection.

PubMed

Goldberger, Tal; Mandelboim, Ofer

2014-11-01

Depending on ethnicity and on social conditions, between 40 and 90 % of the population is infected with human cytomegalovirus (HCMV). In immunocompetent patients, the virus may cause an acute disease and then revert to a state of latency, which enables its coexistence with the human host. However, in cases of immunosuppression or in neonatal infections, HCMV can cause serious long-lasting illnesses. HCMV has developed multiple mechanisms in order to escape its elimination by the immune system, specifically by two killer cell types of the adaptive and the innate immune systems; cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, respectively. Another fascinating aspect of HCMV is that like other highly developed herpesviruses, it expresses its own unique set of microRNAs. Here, we initially describe how the activity of NK cells is regulated under normal conditions and during infection. Then, we discuss what is currently known about HCMV microRNA-mediated interactions, with special emphasis on immune modulation and NK cell evasion. We further illustrate the significant modulation of cellular microRNAs during HCMV infection. Although, the full target spectrum of HCMV microRNAs is far from being completely elucidated, it can already be concluded that HCMV uses its "multitasking" microRNAs to globally affect its own life cycle, as well as important cellular and immune-related pathways.

Activation-specific metabolic requirements for NK cell IFN-γ production1

PubMed Central

Keppel, Molly P.; Topcagic, Nermina; Mah, Annelise Y.; Vogel, Tiphanie P.; Cooper, Megan A.

2014-01-01

There has been increasing recognition of the importance of cellular metabolism and metabolic substrates for the function and differentiation of immune cells. Here, for the first time, we investigate the metabolic requirements for production of IFN-γ by freshly isolated NK cells. Primary murine NK cells mainly utilize mitochondrial oxidative phosphorylation at rest and with short-term activation. Remarkably, we discovered significant differences in the metabolic requirements of murine NK cell IFN-γ production depending upon the activation signal. Stimulation of NK cell IFN-γ production was independent of glycolysis or mitochondrial oxidative phosphorylation when cells were activated with IL-12+IL-18. By contrast, stimulation via activating NK receptors required glucose-driven oxidative phosphorylation. Prolonged treatment with high-dose, but not low dose, IL-15 eliminated the metabolic requirement for receptor stimulation. In summary, this study demonstrates that metabolism provides an essential second signal for induction of IFN-γ production by activating NK cell receptors that can be reversed with prolonged high-dose IL-15 treatment. PMID:25595780

Natural Killer (NK)/melanoma cell interaction induces NK-mediated release of chemotactic High Mobility Group Box-1 (HMGB1) capable of amplifying NK cell recruitment

PubMed Central

Parodi, Monica; Pedrazzi, Marco; Cantoni, Claudia; Averna, Monica; Patrone, Mauro; Cavaletto, Maria; Spertino, Stefano; Pende, Daniela; Balsamo, Mirna; Pietra, Gabriella; Sivori, Simona; Carlomagno, Simona; Mingari, Maria Cristina; Moretta, Lorenzo; Sparatore, Bianca; Vitale, Massimo

2015-01-01

In this study we characterize a new mechanism by which Natural Killer (NK) cells may amplify their recruitment to tumors. We show that NK cells, upon interaction with melanoma cells, can release a chemotactic form of High Mobility Group Box-1 (HMGB1) protein capable of attracting additional activated NK cells. We first demonstrate that the engagement of different activating NK cell receptors, including those mainly involved in tumor cell recognition can induce the active release of HMGB1. Then we show that during NK-mediated tumor cell killing two HMGB1 forms are released, each displaying a specific electrophoretic mobility possibly corresponding to a different redox status. By the comparison of normal and perforin-defective NK cells (which are unable to kill target cells) we demonstrate that, in NK/melanoma cell co-cultures, NK cells specifically release an HMGB1 form that acts as chemoattractant, while dying tumor cells passively release a non-chemotactic HMGB1. Finally, we show that Receptor for Advanced Glycation End products is expressed by NK cells and mediates HMGB1-induced NK cell chemotaxis. Proteomic analysis of NK cells exposed to recombinant HMGB1 revealed that this molecule, besides inducing immediate chemotaxis, also promotes changes in the expression of proteins involved in the regulation of the cytoskeletal network. Importantly, these modifications could be associated with an increased motility of NK cells. Thus, our findings allow the definition of a previously unidentified mechanism used by NK cells to amplify their response to tumors, and provide additional clues for the emerging role of HMGB1 in immunomodulation and tumor immunity. PMID:26587323

Natural Killer Cell Cytotoxicity Against SKOV3 after HLA-G Downregulation by shRNA.

PubMed

Nazari, Nazanin; Farjadian, Shirin

2016-09-01

HLA-G is a nonclassical HLA class I molecule which, when elevated in tumor cells, is one of the main factors involved in tumor evasion of immune responses including NK and T cells. To evaluate the effect of HLA-G downregulation on NK cell cytotoxicity in tumor cell lines. The expression level of HLA-G was measured by real-time PCR and flowcytometry after transfection of SKOV3 by shRNA.1, which targets specific sequences in exon 4, or shRNA.2, which targets both exons 4 and 6. NK-92MI cell cytotoxicity against transfected or untransfected target cell lines was measured with the lactate dehydrogenase (LDH) release assay. The Jeg-3 cell line was used as a positive control. Membrane-bound HLA-G expression levels decreased significantly in both cell lines after transfection with both shRNAs compared to their corresponding untransfected cells (p<0.05). Jeg-3 cells were better lysed than SKOV3 cells by NK cells during the first 48 h after transfection with both shRNAs. Compared to untransfected cells, shRNA.1-transfected SKOV3 cells were significantly more lysed by NK cells 24 h post-transfection (p=0.043). As a clinical approach, HLA-G downregulation with shRNA may be effective in cancer therapy by improving immune cell activation.

Revving up Natural Killer Cells and Cytokine-Induced Killer Cells Against Hematological Malignancies.

PubMed

Pittari, Gianfranco; Filippini, Perla; Gentilcore, Giusy; Grivel, Jean-Charles; Rutella, Sergio

2015-01-01

Natural killer (NK) cells belong to innate immunity and exhibit cytolytic activity against infectious pathogens and tumor cells. NK-cell function is finely tuned by receptors that transduce inhibitory or activating signals, such as killer immunoglobulin-like receptors, NK Group 2 member D (NKG2D), NKG2A/CD94, NKp46, and others, and recognize both foreign and self-antigens expressed by NK-susceptible targets. Recent insights into NK-cell developmental intermediates have translated into a more accurate definition of culture conditions for the in vitro generation and propagation of human NK cells. In this respect, interleukin (IL)-15 and IL-21 are instrumental in driving NK-cell differentiation and maturation, and hold great promise for the design of optimal NK-cell culture protocols. Cytokine-induced killer (CIK) cells possess phenotypic and functional hallmarks of both T cells and NK cells. Similar to T cells, they express CD3 and are expandable in culture, while not requiring functional priming for in vivo activity, like NK cells. CIK cells may offer some advantages over other cell therapy products, including ease of in vitro propagation and no need for exogenous administration of IL-2 for in vivo priming. NK cells and CIK cells can be expanded using a variety of clinical-grade approaches, before their infusion into patients with cancer. Herein, we discuss GMP-compliant strategies to isolate and expand human NK and CIK cells for immunotherapy purposes, focusing on clinical trials of adoptive transfer to patients with hematological malignancies.

Natural killer T cells are required for the development of a superantigen-driven T helper type 2 immune response in mice

PubMed Central

Nomizo, Auro; Postol, Edilberto; de Alencar, Raquel; Cardillo, Fabíola; Mengel, José

2005-01-01

We show, here, that one single injection or weekly injections of staphylococcal enterotoxin B (SEB), starting in 1-day-old newborn mice, induced a powerful immune response with a T helper type 2 (Th2) pattern, as judged by the isotype and cytokine profile, with the production of large amounts of SEB-specific immunoglobulin G1 (IgG1), detectable levels of SEB-specific IgE and increased production of interleukin-4 by spleen cells. These protocols also induced an increase in the levels of total IgE in the serum. Memory of SEB was transferred to secondary recipients by using total spleen cells from primed animals. The secondary humoral response in transferred mice was diminished if spleen cells from SEB-treated mice were previously depleted of CD3+ or Vβ8+ T cells or NK1.1+ cells. In vivo depletion of NK1.1+ cells in adult mice resulted in a marked reduction in the SEB-specific antibody response in both the primary and secondary immune responses. Additionally, purified NK1.1+ T cells were able to perform SEB-specific helper B-cell actions in vitro and in vivo. These results suggest that NK1.1+ T cells are required for the full development of humoral immunological memory, whilst making neonatal tolerance to SEB unachievable. PMID:16162272

Activating and inhibitory receptors on synovial fluid natural killer cells of arthritis patients: role of CD94/NKG2A in control of cytokine secretion

PubMed Central

de Matos, Cristina Teixeira; Berg, Louise; Michaëlsson, Jakob; Felländer-Tsai, Li; Kärre, Klas; Söderström, Kalle

2007-01-01

Natural killer (NK) cells are activated early during inflammatory events and contribute to the shaping of the ensuing adaptive immune response. To further understand the role for NK cells in inflammation, we investigated the phenotype and function of synovial fluid (SF) NK cells from patients with chronic joint inflammation, as well as from patients with transient inflammation of the knee following trauma. We confirm that synovial NK cells are similar to the well-characterized CD56bright peripheral blood (PB) NK-cell subset present in healthy individuals. However, compared to this PB subset the synovial NK cells express a higher degree of activation markers including CD69 and NKp44, the latter being up-regulated also on CD56bright NK cells in the PB of patients. Activated synovial NK cells produced interferon-γ and tumour necrosis factor, and the production was further up-regulated by antibody masking of CD94/NKG2A, and down-regulated by target cells expressing human leucocyte antigen-E in complex with peptides known to engage CD94/NKG2A. We conclude that synovial NK cells have an activated phenotype and that CD94/NKG2A is a key regulator of synovial NK-cell cytokine synthesis. PMID:17521371

Cytokine activation induces human memory-like NK cells.

PubMed

Romee, Rizwan; Schneider, Stephanie E; Leong, Jeffrey W; Chase, Julie M; Keppel, Catherine R; Sullivan, Ryan P; Cooper, Megan A; Fehniger, Todd A

2012-12-06

Natural killer (NK) cells are lymphocytes that play an important role in the immune response to infection and malignancy. Recent studies in mice have shown that stimulation of NK cells with cytokines or in the context of a viral infection results in memory-like properties. We hypothesized that human NK cells exhibit such memory-like properties with an enhanced recall response after cytokine preactivation. In the present study, we show that human NK cells preactivated briefly with cytokine combinations including IL-12, IL-15, and IL-18 followed by a 7- to 21-day rest have enhanced IFN-γ production after restimulation with IL-12 + IL-15, IL-12 + IL-18, or K562 leukemia cells. This memory-like phenotype was retained in proliferating NK cells. In CD56(dim) NK cells, the memory-like IFN-γ response was correlated with the expression of CD94, NKG2A, NKG2C, and CD69 and a lack of CD57 and KIR. Therefore, human NK cells have functional memory-like properties after cytokine activation, which provides a novel rationale for integrating preactivation with combinations of IL-12, IL-15, and IL-18 into NK cell immunotherapy strategies.

“Multi-Omics” Analyses of the Development and Function of Natural Killer Cells

PubMed Central

Zhou, Yonggang; Xu, Xiuxiu; Tian, Zhigang; Wei, Haiming

2017-01-01

For over four decades, our understanding of natural killer (NK) cells has evolved from the original description of cluster of differentiation (CD)56+CD3− to establishing NK cells as an important subset of innate lymphocytes in the host’s surveillance against viral infections and malignancy. The progress of research on the fundamental properties and therapeutic prospects for translational medicine using NK cells excites immunologists and clinicians. Over the past decade, numerous advances in “-omics”-scale methods and new technological approaches have addressed many essential questions in the biology of NK cells. We now have further understanding of the overall molecular mechanisms of action that determine the development, function, plasticity, diversity, and immune reactivity of NK cells. These findings are summarized here, and our view on how to study NK cells using “multi-omics” is highlighted. We also describe “-omics” analyses of the relationships between NK cells and viral infection, tumorigenesis, and autoimmune diseases. Ultimately, a deeper and more comprehensive understanding of NK cells in multiple conditions will provide more effective strategies to manipulate NK cells for the treatment of human disease. PMID:28928751

Distribution of intrahepatic T, NK and CD3(+)CD56(+)NKT cells alters after liver transplantation: Shift from innate to adaptive immunity?

PubMed

Werner, Jens M; Lang, Corinna; Scherer, Marcus N; Farkas, Stefan A; Geissler, Edward K; Schlitt, Hans J; Hornung, Matthias

2011-07-01

The liver is an immunological organ containing a large number of T, NK and NKT cells, but little is known about intrahepatic immunity after LTx. Here, we investigated whether the distribution of T, NK and CD3(+)CD56(+)NKT cells is altered in transplanted livers under different circumstances. Core biopsies of transplanted livers were stained with antibodies against CD3 and CD56. Several cell populations including T (CD3(+)CD56(-)), NK (CD3(-)CD56(+)) and NKT cells (CD3(+)CD56(+)) were studied by fluorescence microscopy. Cell numbers were analyzed in relation to the time interval after LTx, immunosuppressive therapy and stage of acute graft rejection (measured with the rejection activity index: RAI) compared to tumor free liver tissue from patients after liver resection due to metastatic disease as control. Recruitment of CD3(+)CD56(+)NKT cells revealed a significant decrease during high RAI scores in comparison to low and middle RAI scores (RAI 7-9: 0.03±0.01/HPF vs. RAI 4-6: 0.1±0.005/HPF). CD3(+)CD56(+)NKT cells were also lower during immunosuppressive therapy with tacrolimus (0.03±0.01/HPF) than with cyclosporine (0.1±0.003/HPF), cyclosporine/MMF (0.1±0.003/HPF) or sirolimus (0.1±0.01/HPF) treatment. Intrahepatic T cell numbers increased significantly 50days after LTx compared to control liver tissue (4.5±0.2/HPF vs. 1.9±0.1/HPF). In contrast, NK cells (0.3±0.004/HPF) were significantly fewer in all biopsies after LTx compared to the control (0.7±0.04/HPF). These data indicate significant alterations in the hepatic recruitment of T, NK and CD3(+)CD56(+)NKT cells after LTx. The increase in T cells and the decrease in NK and CD3(+)CD56(+)NKT cells suggest a shift from innate to adaptive hepatic immunity in the liver graft. Copyright © 2011 Elsevier B.V. All rights reserved.

Is There Natural Killer Cell Memory and Can It Be Harnessed by Vaccination? Vaccination Strategies Based on NK Cell and ILC Memory.

PubMed

Cooper, Megan A; Fehniger, Todd A; Colonna, Marco

2017-12-18

Studies over the last decade have decisively shown that innate immune natural killer (NK) cells exhibit enhanced long-lasting functional responses following a single activation event. With the increased recognition of memory and memory-like properties of NK cells, questions have arisen with regard to their ability to effectively mediate vaccination responses in humans. Moreover, recently discovered innate lymphoid cells (ILCs) could also potentially exhibit memory-like functions. Here, we review different forms of NK cell memory, and speculate about the ability of these cells and ILCs to meaningfully contribute to vaccination responses. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

Immunomodulatory effects of Hericium erinaceus derived polysaccharides are mediated by intestinal immunology.

PubMed

Sheng, Xiaotong; Yan, Jingmin; Meng, Yue; Kang, Yuying; Han, Zhen; Tai, Guihua; Zhou, Yifa; Cheng, Hairong

2017-03-22

This study was aimed at investigating the immunomodulating activity of Hericium erinaceus polysaccharide (HEP) in mice, by assessing splenic lymphocyte proliferation (cell-mediated immunity), serum hemolysin levels (humoral immunity), phagocytic capacity of peritoneal cavity phagocytes (macrophage phagocytosis), and NK cell activity. ELISA of immunoglobulin A (SIgA) in the lamina propria, and western blotting of small intestinal proteins were also performed to gain insight into the mechanism by which HEP affects the intestinal immune system. Here, we report that HEP improves immune function by functionally enhancing cell-mediated and humoral immunity, macrophage phagocytosis, and NK cell activity. In addition, HEP was found to upregulate the secretion of SIgA and activate the MAPK and AKT cellular signaling pathways in the intestine. In conclusion, all these results allow us to postulate that the immunomodulatory effects of HEP are most likely attributed to the effective regulation of intestinal mucosal immune activity.

The Chinese Herbal Mixture Tien-Hsien Liquid Augments the Anticancer Immunity in Tumor Cell–Vaccinated Mice

PubMed Central

Yang, Pei-Ming; Du, Jia-Ling; Wang, George Nian-Kae; Chia, Jean-San; Hsu, Wei-Bin; Pu, Pin-Ching; Sun, Andy; Chiang, Chun-Pin; Wang, Won-Bo

2016-01-01

Background. The Chinese herbal mixture, Tien-Hsien liquid (THL), has been used as an anticancer dietary supplement for more than 20 years. Our previous studies have shown that THL can modulate immune responseand inhibit tumor growth. In this study, we further evaluated the effect of THL on anticancer immune response in mice vaccinated with γ-ray-irradiated tumor cells. Methods. The antitumor effect of THL was determined in mice vaccinated with low-tumorigenic CT-26-low colon cancer cells or γ-ray-irradiated high-tumorigenic CT-26-high colon cancer cells. The number of natural killer (NK) cells and T lymphocytes in the spleen was analyzed by flow cytometry. The tumor-killing activities of NK cells and cytotoxic T lymphocytes (CTLs) were analyzed by flow cytometry using YAC-1 and CT-26-high cells, respectively, as target cells. The levels of IFN-γ, IL-2, and TNF-α were determined by ELISA. Results. THL suppressed the growth of CT-26-high tumor in mice previously vaccinated with low-tumorigenic CT-26-low cells or γ-irradiated CT-26-high cells. THL increased the populations of NK cells and CD4+ T lymphocytes in the spleen and enhanced the tumor-killing activities of NK cells and CTL in mice vaccinated with γ-irradiated CT-26-high cells. THL increased the production of IFN-γ, IL-2, and TNF-α in mice vaccinated with γ-irradiated CT-26-high cells. Conclusion. THL can enhance the antitumor immune responses in mice vaccinated with killed tumor cells. These results suggest that THL may be used as a complementary medicine for cancer patients previously treated with killed tumor cell vaccines, radiotherapy, or chemotherapy. PMID:27252074

Immune cell inhibition by SLAMF7 is mediated by a mechanism requiring src kinases, CD45, and SHIP-1 that is defective in multiple myeloma cells.

PubMed

Guo, Huaijian; Cruz-Munoz, Mario-Ernesto; Wu, Ning; Robbins, Michael; Veillette, André

2015-01-01

Signaling lymphocytic activation molecule F7 (SLAMF7) is a receptor present on immune cells, including natural killer (NK) cells. It is also expressed on multiple myeloma (MM) cells. This led to development of an anti-SLAMF7 antibody, elotuzumab, showing efficacy against MM. SLAMF7 mediates activating or inhibitory effects in NK cells, depending on whether cells express or do not express the adaptor EAT-2. Since MM cells lack EAT-2, we elucidated the inhibitory effectors of SLAMF7 in EAT-2-negative NK cells and tested whether these effectors were triggered in MM cells. SLAMF7-mediated inhibition in NK cells lacking EAT-2 was mediated by SH2 domain-containing inositol phosphatase 1 (SHIP-1), which was recruited via tyrosine 261 of SLAMF7. Coupling of SLAMF7 to SHIP-1 required Src kinases, which phosphorylated SLAMF7. Although MM cells lack EAT-2, elotuzumab did not induce inhibitory signals in these cells. This was at least partly due to a lack of CD45, a phosphatase required for Src kinase activation. A defect in SLAMF7 function was also observed in CD45-deficient NK cells. Hence, SLAMF7-triggered inhibition is mediated by a mechanism involving Src kinases, CD45, and SHIP-1 that is defective in MM cells. This defect might explain why elotuzumab eliminates MM cells by an indirect mechanism involving the activation of NK cells. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Effective modulation of CD4(+)CD25 (+high) regulatory T and NK cells in malignant patients by combination of interferon-α and interleukin-2.

PubMed

Liu, Guangxian; Yang, Wuwei; Guo, Mei; Liu, Xiaoqing; Huang, Naixiang; Li, Dingfeng; Jiang, Zefei; Yang, Wenfeng; Zhang, Weijing; Su, Hang; Liu, Zhiqing; Liu, Tieqiang; Wang, Dongmei; Huang, Shan; Yao, Bo; Man, Qiuhong; Qiu, Lijuan; Sun, Xuedong; Sun, Yuying; Liu, Bing

2012-12-01

Overinduced CD4(+)CD25(+high) regulatory T cells (Treg) and downregulated NK cells contribute to tumor-relevant immune tolerance and interfere with tumor immunity. In this study, we aimed to design a novel strategy with cytokine combination to correct the dysregulated Treg and NK cells in malignant patients. Initially, a total of 58 healthy individuals and 561 malignant patients were analyzed for their cellular immunity by flow cytometry. The average percentages of CD4(+)CD25(+high)/lymphocyte were 1.30 ± 1.19 % ([Formula: see text] ± SD) in normal adults and 3.274 ± 4.835 % in malignant patients (p < 0.001). The ratio of CD4(+)CD25(+high) to CD4(+) was 3.58 ± 3.19 % in normal adults and 6.01 ± 5.89 % to 13.50 ± 23.60 % in different kinds of malignancies (p < 0.001). Of normal adults, 15.52 % had >3 % Treg and 12.07 % had <10 % NK cells. In contrast, the Treg (>3 %) and NK (<10 %) percentages were 40.82 and 34.94 % in malignant patients, respectively. One hundred and ten patients received the immunomodulation therapy with IFN-α and/or IL-2. The overinduced Treg in 86.3 % and the reduced NK cells in 71.17 % of the patients were successfully modulated. In comparison, other lymphocyte subpopulations in most patients were much less affected by this treatment. No other treatment-relevant complications except slight pyrexia, fatigue, headache, and myalgia were observed. In conclusion, dysregulated Treg and/or NK cells were common in malignant patients. Different from any regimens ever reported, this strategy was simple and effective without severe complications and will become a basic regimen for other cancer therapies.

Metronomic cyclophosphamide eradicates large implanted GL261 gliomas by activating antitumor Cd8+ T-cell responses and immune memory

PubMed Central

Wu, Junjie; Waxman, David J

2015-01-01

Cancer chemotherapy using cytotoxic drugs can induce immunogenic tumor cell death; however, dosing regimens and schedules that enable single-agent chemotherapy to induce adaptive immune-dependent ablation of large, established tumors with activation of long-term immune memory have not been identified. Here, we investigate this issue in a syngeneic, implanted GL261 glioma model in immune-competent mice given cyclophosphamide on a 6-day repeating metronomic schedule. Two cycles of metronomic cyclophosphamide treatment induced sustained upregulation of tumor-associated CD8+ cytotoxic T lymphocyte (CTL) cells, natural killer (NK) cells, macrophages, and other immune cells. Expression of CTL- and NK–cell-shared effectors peaked on Day 6, and then declined by Day 9 after the second cyclophosphamide injection and correlated inversely with the expression of the regulatory T cell (Treg) marker Foxp3. Sustained tumor regression leading to tumor ablation was achieved after several cyclophosphamide treatment cycles. Tumor ablation required CD8+ T cells, as shown by immunodepletion studies, and was associated with immunity to re-challenge with GL261 glioma cells, but not B16-F10 melanoma or Lewis lung carcinoma cells. Rejection of GL261 tumor re-challenge was associated with elevated CTLs in blood and increased CTL infiltration in tumors, consistent with the induction of long-term, specific CD8+ T-cell anti-GL261 tumor memory. Co-depletion of CD8+ T cells and NK cells did not inhibit tumor regression beyond CD8+ T-cell depletion alone, suggesting that the metronomic cyclophosphamide-activated NK cells function via CD8a+ T cells. Taken together, these findings provide proof-of-concept that single-agent chemotherapy delivered on an optimized metronomic schedule can eradicate large, established tumors and induce long-term immune memory. PMID:26137402

β-Endorphin Neuronal Cell Transplant Reduces Corticotropin Releasing Hormone Hyperresponse to Lipopolysaccharide and Eliminates Natural Killer Cell Functional Deficiencies in Fetal Alcohol Exposed Rats

PubMed Central

Boyadjieva, Nadka I.; Ortigüela, María; Arjona, Alvaro; Cheng, Xiaodong; Sarkar, Dipak K.

2010-01-01

Background Natural killer (NK) cell dysfunction is associated with hyperresponse of corticotropin releasing hormone (CRH) to immune challenge and with a loss of β-endorphin (BEP) neurons in fetal alcohol exposed animals. Recently, we established a method to differentiate neural stem cells into BEP neurons using cyclic adenosine monophosphate (cAMP)-elevating agents in cultures. Hence, we determined whether in vitro differentiated BEP neurons could be used for reversing the compromised stress response and immune function in fetal alcohol exposed rats. Methods To determine the effect of BEP neuron transplants on NK cell function, we implanted in vitro differentiated BEP neurons into the paraventricular nucleus of pubertal and adult male rats exposed to ethanol or control in utero. The functionality of transplanted BEP neurons was determined by measuring proopiomelanocortin (POMC) gene expression in these cells and their effects on CRH gene expression under basal and after lipopolysaccaride (LPS) challenge. In addition, the effectiveness of BEP neurons in activating NK cell functions is determined by measuring NK cell cytolytic activity and interferon-γ (IFN-γ) production in the spleen and in the peripheral blood mononuclear cell (PBMC) following cell transplantation. Results We showed here that when these in vitro differentiated BEP neurons were transplanted into the hypothalamus, they maintain biological functions by producing POMC and reducing the CRH neuronal response to the LPS challenge. BEP neuronal transplants significantly increased NK cell cytolytic activity in the spleen and in the PBMC and increased plasma levels of IFN-γ in control and fetal alcohol exposed rats. Conclusions These data further establish the BEP neuronal regulatory role in the control of CRH and NK cell cytolytic function and identify a possible novel therapy to treat stress hyper-response and immune deficiency in fetal alcohol exposed subjects. PMID:19320628

Immune effects of nickel.

PubMed

Salsano, F; Francia, C; Roumpedaki, I; Proietti, M; Pisarri, S; Verna, N; Gabriele, E; Di Gioacchino, G; Di Gioacchino, M

2004-01-01

Data on nickel immunomodulation are contradictory. The most consistent immune effects are suppression of immune responses. It has been shown that T-lymphocytes and NK cells are more susceptible to nickel toxicity than are B lymphocytes or macrophages. Data reported about cytokine production in human and nickel reactive T-cell clones are also conflicting. Some authors studied showed a higher synthesis of IL4, IL5 and IL13 but not of IFN gamma and TNFalpha in Ni allergic subjects. We found that the addiction on NiSo4 to the PBMC cultures of non sensitised subjects induces a reduction of release of IL5, IFN gamma and TNFalpha. Our studies demonstrate a clear difference in the NK cell activity between nickel-tolerant and intolerant individuals. In particular NK cell activity in reduced in sensitised patients respect to the normal subjects and the addition of Ni has immunotoxic potential. Researches are in progress in an Attempt to correlate the present data with other immune parameters and to measure the effects of a Ni Free diet on the immune system of subjects with Ni intolerance. The comprehension of the mechanisms inducing these changes requires further studies in the uptake and intracellular distribution and binding of the metal.

The major histocompatibility complex class Ib molecule HLA-E at the interface between innate and adaptive immunity.

PubMed

Sullivan, L C; Clements, C S; Rossjohn, J; Brooks, A G

2008-11-01

The non-classical major histocompatibility complex (MHC) class I molecule human leucocyte antigen (HLA)-E is the least polymorphic of all the MHC class I molecules and acts as a ligand for receptors of both the innate and the adaptive immune systems. The recognition of self-peptides complexed to HLA-E by the CD94-NKG2A receptor expressed by natural killer (NK) cells represents a crucial checkpoint for immune surveillance by NK cells. However, HLA-E can also be recognised by the T-cell receptor expressed by alphabeta CD8 T cells and therefore can play a role in the adaptive immune response to invading pathogens. The recent resolution of HLA-E in complex with both innate and adaptive ligands has provided insight into the dual role of this molecule in immunity.

Natural Killer (NK) Cell Functionality after human Spinal Cord Injury (SCI): protocol of a prospective, longitudinal study.

PubMed

Laginha, Inês; Kopp, Marcel A; Druschel, Claudia; Schaser, Klaus-Dieter; Brommer, Benedikt; Hellmann, Rick C; Watzlawick, Ralf; Ossami-Saidi, Ramin-Raul; Prüss, Harald; Failli, Vieri; Meisel, Christian; Liebscher, Thomas; Prilipp, Erik; Niedeggen, Andreas; Ekkernkamp, Axel; Grittner, Ulrike; Piper, Sophie K; Dirnagl, Ulrich; Killig, Monica; Romagnani, Chiara; Schwab, Jan M

2016-09-13

Natural killer (NK) cells comprise the main components of lymphocyte-mediated nonspecific immunity. Through their effector function they play a crucial role combating bacterial and viral challenges. They are also thought to be key contributors to the systemic spinal cord injury-induced immune-deficiency syndrome (SCI-IDS). SCI-IDS increases susceptibility to infection and extends to the post-acute and chronic phases after SCI. The prospective study of NK cell function after traumatic SCI was carried out in two centers in Berlin, Germany. SCI patients and control patients with neurologically silent vertebral fracture also undergoing surgical stabilization were enrolled. Furthermore healthy controls were included to provide reference data. The NK cell function was assessed at 7 (5-9) days, 14 days (11-28) days, and 10 (8-12) weeks post-trauma. Clinical documentation included the American Spinal Injury Association (ASIA) impairment scale (AIS), neurological level of injury, infection status, concomitant injury, and medications. The primary endpoint of the study is CD107a expression by NK cells (cytotoxicity marker) 8-12 weeks following SCI. Secondary endpoints are the NK cell's TNF-α and IFN-γ production by the NK cells 8-12 weeks following SCI. The protocol of this study was developed to investigate the hypotheses whether i) SCI impairs NK cell function throughout the post-acute and sub-acute phases after SCI and ii) the degree of impairment relates to lesion height and severity. A deeper understanding of the SCI-IDS is crucial to enable strategies for prevention of infections, which are associated with poor neurological outcome and elevated mortality. DRKS00009855 .

CX3CR1-dependent recruitment of mature NK cells into the central nervous system contributes to control autoimmune neuroinflammation.

PubMed

Hertwig, Laura; Hamann, Isabell; Romero-Suarez, Silvina; Millward, Jason M; Pietrek, Rebekka; Chanvillard, Coralie; Stuis, Hanna; Pollok, Karolin; Ransohoff, Richard M; Cardona, Astrid E; Infante-Duarte, Carmen

2016-08-01

Fractalkine receptor (CX3CR1)-deficient mice develop very severe experimental autoimmune encephalomyelitis (EAE), associated with impaired NK cell recruitment into the CNS. Yet, the precise implications of NK cells in autoimmune neuroinflammation remain elusive. Here, we investigated the pattern of NK cell mobilization and the contribution of CX3CR1 to NK cell dynamics in the EAE. We show that in both wild-type and CX3CR1-deficient EAE mice, NK cells are mobilized from the periphery and accumulate in the inflamed CNS. However, in CX3CR1-deficient mice, the infiltrated NK cells displayed an immature phenotype contrasting with the mature infiltrates in WT mice. This shift in the immature/mature CNS ratio contributes to EAE exacerbation in CX3CR1-deficient mice, since transfer of mature WT NK cells prior to immunization exerted a protective effect and normalized the CNS NK cell ratio. Moreover, mature CD11b(+) NK cells show higher degranulation in the presence of autoreactive 2D2 transgenic CD4(+) T cells and kill these autoreactive cells more efficiently than the immature CD11b(-) fraction. Together, these data suggest a protective role of mature NK cells in EAE, possibly through direct modulation of T cells inside the CNS, and demonstrate that mature and immature NK cells are recruited into the CNS by distinct chemotactic signals. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Induction of anti-glioma NK cell response following multiple low-dose intracerebral CpG therapy

PubMed Central

Alizadeh, Darya; Zhang, Leying; Brown, Christine E.; Farrukh, Omar; Jensen, Michael C.; Badie, Behnam

2010-01-01

Purpose Stimulation of toll-like receptor-9 (TLR9) by CpG oligodeoxynucleotides (CpG-ODN) has been shown to counteract the immunosuppressive microenvironment and to inhibit tumor growth in glioma models. These studies, however, have used high doses of CpG-ODN which can induce toxicity in a clinical setting. The goal of this study was to evaluate the anti-tumor efficacy of multiple low-dose intratumoral CpG- ODN in a glioma model. Experimental Design Mice bearing four-day old intracranial GL261 gliomas received a single or multiple (two or four) intratumoral injections of CpG-ODN (3 μg) every 4 days. Tumor growth was measured by bioluminescent imaging, brain histology, and animal survival. Flow cytometry and cytotoxicity assays were used to assess anti-glioma immune response. Results Two and four intracranial injections of low-dose CpG-ODN, but not a single injection, eradicated gliomas in 70% of mice. Moreover, surviving animals exhibited durable tumor free remission (> 3 months), and were protected from intracranial rechallenge with GL21 gliomas, demonstrating the capacity for long-term anti-tumor immunity. Although most inflammatory cells appeared to increase, activated NK cells (i.e. NK+CD107a+) were more frequent than CD8+CD107a+ in the brains of rechallenged CpG-ODN-treated animals and demonstrated a stronger in vitro cytotoxicity against GL261 target cells. Leukocyte depletion studies confirmed that NK cells played an important role in the initial CpG-ODN anti-tumor response, but both CD8 and NK cells were equally important in long-term immunity against gliomas. Conclusions These findings suggest that multiple low-dose intratumoral injections of CpG-ODN can eradicate intracranial gliomas possibly through mechanisms involving NK mediated effector function. PMID:20570924

Cancer immunoediting by the innate immune system in the absence of adaptive immunity

PubMed Central

O’Sullivan, Timothy; Saddawi-Konefka, Robert; Vermi, William; Koebel, Catherine M.; Arthur, Cora; White, J. Michael; Uppaluri, Ravi; Andrews, Daniel M.; Ngiow, Shin Foong; Teng, Michele W.L.; Smyth, Mark J.; Schreiber, Robert D.

2012-01-01

Cancer immunoediting is the process whereby immune cells protect against cancer formation by sculpting the immunogenicity of developing tumors. Although the full process depends on innate and adaptive immunity, it remains unclear whether innate immunity alone is capable of immunoediting. To determine whether the innate immune system can edit tumor cells in the absence of adaptive immunity, we compared the incidence and immunogenicity of 3′methylcholanthrene-induced sarcomas in syngeneic wild-type, RAG2−/−, and RAG2−/−x γc−/− mice. We found that innate immune cells could manifest cancer immunoediting activity in the absence of adaptive immunity. This activity required natural killer (NK) cells and interferon γ (IFN-γ), which mediated the induction of M1 macrophages. M1 macrophages could be elicited by administration of CD40 agonists, thereby restoring editing activity in RAG2−/−x γc−/− mice. Our results suggest that in the absence of adaptive immunity, NK cell production of IFN-γ induces M1 macrophages, which act as important effectors during cancer immunoediting. PMID:22927549

Suppression of innate immunity (natural killer cell/interferon-γ) in the advanced stages of liver fibrosis in mice

PubMed Central

Jeong, Won-Il; Park, Ogyi; Suh, Yang-Gun; Byun, Jin-Seok; Park, So-Young; Choi, Earl; Kim, Ja-Kyung; Ko, Hyojin; Wang, Hua; Miller, Andrew M.; Gao, Bin

2011-01-01

Activation of innate immunity (natural killer cell/interferon-γ: NK cell/IFN-γ) has been shown to play an important role in anti-viral and anti-tumor defenses as well as anti-fibrogenesis. However, little is known about the regulation of innate immunity during chronic liver injury. Here, we compared the functions of NK cells in early and advanced liver fibrosis induced by a 2-week or a 10 week-carbon tetrachloride (CCl4) challenge, respectively. Injection of poly I:C or IFN-γ induced NK cell activation and NK cell killing of hepatic stellate cells (HSCs) in the 2-week CCl4 model. Such activation was diminished in the 10-week CCl4 model. Consistent with these findings, the inhibitory effect of poly I:C and IFN-γ on liver fibrosis was markedly reduced in the 10-week vs. the 2-week CCl4 model. In vitro co-culture experiments demonstrated that 4-day cultured (early-activated) HSCs induce NK cell activation via an NKG2D-retinoic acid-induced early gene 1 (RAE1)-dependent mechanism. Such activation was reduced when co-cultured with 8-day cultured (intermediately-activated) HSCs due to the production of transforming growth factor-β (TGF-β) by HSCs. Moreover, early-activated HSCs were sensitive, while intermediately-activated HSCs were resistant to IFN-γ mediated inhibition of cell proliferation, likely due to elevated expression of suppressor of cytokine signaling 1 (SOCS1). Disruption of the SOCS1 gene restored the IFN-γ inhibition of cell proliferation in intermediately-activated HSCs. Production of retinol metabolites by HSCs contributed to SOCS1 induction and subsequently inhibited IFN-γ signaling and functioning, while production of TGF-β by HSCs inhibited NK cell function and cytotoxicity against HSCs. Conclusion The anti-fibrogenic effects of NK cell/IFN-γ are suppressed during advanced liver injury, which is likely due to the increased production of TGF-β and expression of SOCS1 in intermediately-activated HSCs. PMID:21480338

Ras-related C3 Botulinum Toxin Substrate (Rac) and Src Family Kinases (SFK) Are Proximal and Essential for Phosphatidylinositol 3-Kinase (PI3K) Activation in Natural Killer (NK) Cell-mediated Direct Cytotoxicity against Cryptococcus neoformans*

PubMed Central

Xiang, Richard F.; Stack, Danuta; Huston, Shaunna M.; Li, Shu Shun; Ogbomo, Henry; Kyei, Stephen K.; Mody, Christopher H.

2016-01-01

The activity of Rac in leukocytes is essential for immunity. However, its role in NK cell-mediated anti-microbial signaling remains unclear. In this study, we investigated the role of Rac in NK cell mediated anti-cryptococcal killing. We found that Cryptococcus neoformans independently activates both Rac and SFK pathways in NK cells, and unlike in tumor killing, Cryptococcus initiated a novel Rac → PI3K → Erk cytotoxicity cascade. Remarkably, Rac was not required for conjugate formation, despite its essential role in NK cytotoxicity against C. neoformans. Taken together, our data show that, unlike observations with tumor cells, NK cells use a novel Rac cytotoxicity pathway in conjunction with SFK, to kill C. neoformans. PMID:26867574

Substance P inhibits natural killer cell cytotoxicity through the neurokinin-1 receptor.

PubMed

Monaco-Shawver, Linda; Schwartz, Lynnae; Tuluc, Florin; Guo, Chang-Jiang; Lai, Jian Ping; Gunnam, Satya M; Kilpatrick, Laurie E; Banerjee, Pinaki P; Douglas, Steven D; Orange, Jordan S

2011-01-01

SP is a potent neuroimmunomodulator that functions through ligating members of the neurokinin receptor family, one of which, NK1R, is widely expressed in immune cells. As in humans, circulating SP levels are increased in pathologic states associated with impairment of NK cell functions, such as depression and HIV infection, we hypothesized that SP has a direct, inhibitory effect upon NK cells. We have studied a clonal human NK cell line (YTS) as well as ex vivo human NK cells and have determined that truncated and full-length NK1R isoforms are expressed in and SP bound by ex vivo NK cells and the YTS NK cell line. Incubation of YTS cells with 10⁻⁶ M SP and ex vivo NK cells with 10⁻⁵ M SP inhibited cytotoxic ability by ∼20% and reduced degranulation. This inhibitory effect upon cytotoxicity was partially prevented by the NK1R antagonist CP96,345. The treatment of YTS or ex vivo NK cells with SP neither down-modulated NCR expression nor affected triggering receptor-induced NF-κB activation. Preincubation of YTS cells with SP, however, did abbreviate the typically prolonged intracellular calcium increase induced by target cell engagement and reduced triggering receptor-induced pERK. Thus, SP has the potential to regulate NK cell functions and acts downstream from neurokinin receptors to modulate NK cell activation signaling. This mechanism may contribute to impairment of NK cell function in certain disease states associated with increased circulating SP. Antagonism of this system may present an opportunity to augment NK cell function therapeutically in selected human diseases.

The head and neck cancer immune landscape and its immunotherapeutic implications

PubMed Central

Mandal, Rajarsi; Şenbabaoğlu, Yasin; Havel, Jonathan J.; Dalin, Martin G.; Riaz, Nadeem; Lee, Ken-Wing; Ganly, Ian; Hakimi, A. Ari; Chan, Timothy A.; Morris, Luc G.T.

2016-01-01

Recent clinical trials have demonstrated a clear survival advantage in advanced head and neck squamous cell carcinoma (HNSCC) patients treated with immune checkpoint blockade. These emerging results reveal that HNSCC is one of the most promising frontiers for immunotherapy research. However, further progress in head and neck immuno-oncology will require a detailed understanding of the immune infiltrative landscape found in these tumors. We leveraged transcriptome data from 280 tumors profiled by The Cancer Genome Atlas (TCGA) to comprehensively characterize the immune landscape of HNSCC in order to develop a rationale for immunotherapeutic strategies in HNSCC and guide clinical investigation. We find that both HPV+ and HPV– HNSCC tumors are among the most highly immune-infiltrated cancer types. Strikingly, HNSCC had the highest median Treg/CD8+ T cell ratio and the highest levels of CD56dim NK cell infiltration, in our pan-cancer analysis of the most immune-infiltrated tumors. CD8+ T cell infiltration and CD56dim NK cell infiltration each correlated with superior survival in HNSCC. Tumors harboring genetic smoking signatures had lower immune infiltration and were associated with poorer survival, suggesting these patients may benefit from immune agonist therapy. These findings illuminate the immune landscape of HPV+ and HPV– HNSCC. Additionally, this landscape provides a potentially novel rationale for investigation of agents targeting modulators of Tregs (e.g., CTLA-4, GITR, ICOS, IDO, and VEGFA) and NK cells (e.g., KIR, TIGIT, and 4-1BB) as adjuncts to anti–PD-1 in the treatment of advanced HNSCC. PMID:27777979

PD-1 mediates functional exhaustion of activated NK cells in patients with Kaposi sarcoma

PubMed Central

Beldi-Ferchiou, Asma; Lambert, Marion; Dogniaux, Stéphanie; Vély, Frédéric; Vivier, Eric; Olive, Daniel; Dupuy, Stéphanie; Levasseur, Frank; Zucman, David; Lebbé, Céleste; Sène, Damien; Hivroz, Claire; Caillat-Zucman, Sophie

2016-01-01

Programmed Death-1 (PD-1), an inhibitory receptor expressed by activated lymphocytes, is involved in regulating T- and B-cell responses. PD-1 and its ligands are exploited by a variety of cancers to facilitate tumor escape through PD-1-mediated functional exhaustion of effector T cells. Here, we report that PD-1 is upregulated on Natural Killer (NK) cells from patients with Kaposi sarcoma (KS). PD-1 was expressed in a sub-population of activated, mature CD56dimCD16pos NK cells with otherwise normal expression of NK surface receptors. PD-1pos NK cells from KS patients were hyporesponsive ex vivo following direct triggering of NKp30, NKp46 or CD16 activating receptors, or short stimulation with NK cell targets. PD-1pos NK cells failed to degranulate and release IFNγ, but exogenous IL-2 or IL-15 restored this defect. That PD-1 contributed to NK cell functional impairment and was not simply a marker of dysfunctional NK cells was confirmed in PD-1-transduced NKL cells. In vitro, PD-1 was induced at the surface of healthy control NK cells upon prolonged contact with cells expressing activating ligands, i.e. a condition mimicking persistent stimulation by tumor cells. Thus, PD-1 appears to plays a critical role in mediating NK cell exhaustion. The existence of this negative checkpoint fine-tuning NK activation highlights the possibility that manipulation of the PD-1 pathway may be a strategy for circumventing tumor escape not only from the T cell-, but also the NK-cell mediated immune surveillance. PMID:27662664

Immune evasion via PD-1/PD-L1 on NK cells and monocyte/macrophages is more prominent in Hodgkin lymphoma than DLBCL

PubMed Central

Vari, Frank; Arpon, David; Keane, Colm; Hertzberg, Mark S.; Talaulikar, Dipti; Jain, Sanjiv; Cui, Qingyan; Han, Erica; Tobin, Josh; Bird, Robert; Cross, Donna; Hernandez, Annette; Gould, Clare; Birch, Simone

2018-01-01

Much focus has been on the interaction of programmed cell death ligand 1 (PD-L1) on malignant B cells with programmed cell death 1 (PD-1) on effector T cells in inhibiting antilymphoma immunity. We sought to establish the contribution of natural killer (NK) cells and inhibitory CD163+ monocytes/macrophages in Hodgkin lymphoma (cHL) and diffuse large B-cell lymphoma (DLBCL). Levels of PD-1 on NK cells were elevated in cHL relative to DLBCL. Notably, CD3−CD56hiCD16-ve NK cells had substantially higher PD-1 expression relative to CD3−CD56dimCD16+ cells and were expanded in blood and tissue, more marked in patients with cHL than patients with DLBCL. There was also a raised population of PD-L1-expressing CD163+ monocytes that was more marked in patients with cHL compared with patients with DLBCL. The phenotype of NK cells and monocytes reverted back to normal once therapy (ABVD [doxorubicin 25 mg/m2, bleomycin 10 000 IU/m2, vinblastine 6 mg/m2, dacarbazine 375 mg/m2, all given days 1 and 15, repeated every 28 days] or R-CHOP [rituximab 375 mg/m2, cyclophosphamide 750 mg/m2 IV, doxorubicin 50 mg/m2 IV, vincristine 1.4 mg/m2 (2 mg maximum) IV, prednisone 100 mg/day by mouth days 1-5, pegfilgrastim 6 mg subcutaneously day 4, on a 14-day cycle]) had commenced. Tumor-associated macrophages (TAMs) expressed high levels of PD-L1/PD-L2 within diseased lymph nodes. Consistent with this, CD163/PD-L1/PD-L2 gene expression was also elevated in cHL relative to DLBCL tissues. An in vitro functional model of TAM-like monocytes suppressed activation of PD-1hi NK cells, which was reversed by PD-1 blockade. In line with these findings, depletion of circulating monocytes from the blood of pretherapy patients with cHL and patients with DLBCL enhanced CD3−CD56hiCD16-ve NK-cell activation. We describe a hitherto unrecognized immune evasion strategy mediated via skewing toward an exhausted PD-1-enriched CD3−CD56hiCD16-ve NK-cell phenotype. In addition to direct inhibition of NK cells by the malignant B cell, suppression of NK cells can occur indirectly by PD-L1/PD-L2-expressing TAMs. The mechanism is more prominent in cHL than DLBCL, which may contribute to the clinical sensitivity of cHL to PD-1 blockade. PMID:29449276

Stimulation of Natural Killer Cell-Mediated Tumor Immunity by an IL15/TGFβ-Neutralizing Fusion Protein.

PubMed

Ng, Spencer; Deng, Jiusheng; Chinnadurai, Raghavan; Yuan, Shala; Pennati, Andrea; Galipeau, Jacques

2016-10-01

The clinical efficacy of immune cytokines used for cancer therapy is hampered by elements of the immunosuppressive tumor microenvironment such as TGFβ. Here we demonstrate that FIST15, a recombinant chimeric protein composed of the T-cell-stimulatory cytokine IL15, the sushi domain of IL15Rα and a TGFβ ligand trap, can overcome immunosuppressive TGFβ to effectively stimulate the proliferation and activation of natural killer (NK) and CD8 + T cells with potent antitumor properties. FIST15-treated NK and CD8 + T cells produced more IFNγ and TNFα compared with treatment with IL15 and a commercially available TGFβ receptor-Fc fusion protein (sTβRII) in the presence of TGFβ. Murine B16 melanoma cells, which overproduce TGFβ, were lysed by FIST15-treated NK cells in vitro at doses approximately 10-fold lower than NK cells treated with IL15 and sTβRII. Melanoma cells transduced to express FIST15 failed to establish tumors in vivo in immunocompetent murine hosts and could only form tumors in beige mice lacking NK cells. Mice injected with the same cells were also protected from subsequent challenge by unmodified B16 melanoma cells. Finally, mice with pre-established B16 melanoma tumors responded to FIST15 treatment more strongly compared with tumors treated with control cytokines. Taken together, our results offer a preclinical proof of concept for the use of FIST15 as a new class of biological therapeutics that can coordinately neutralize the effects of immunosuppressive TGFβ in the tumor microenvironment while empowering tumor immunity. Cancer Res; 76(19); 5683-95. ©2016 AACR. ©2016 American Association for Cancer Research.

Inhibition of bromodomain and extra-terminal (BET) proteins increases NKG2D ligand MICA expression and sensitivity to NK cell-mediated cytotoxicity in multiple myeloma cells: role of cMYC-IRF4-miR-125b interplay.

PubMed

Abruzzese, Maria Pia; Bilotta, Maria Teresa; Fionda, Cinzia; Zingoni, Alessandra; Soriani, Alessandra; Vulpis, Elisabetta; Borrelli, Cristiana; Zitti, Beatrice; Petrucci, Maria Teresa; Ricciardi, Maria Rosaria; Molfetta, Rosa; Paolini, Rossella; Santoni, Angela; Cippitelli, Marco

2016-12-01

Anti-cancer immune responses may contribute to the control of tumors after conventional chemotherapy, and different observations have indicated that chemotherapeutic agents can induce immune responses resulting in cancer cell death and immune-stimulatory side effects. Increasing experimental and clinical evidence highlight the importance of natural killer (NK) cells in immune responses toward multiple myeloma (MM), and combination therapies able to enhance the activity of NK cells against MM are showing promise in treating this hematologic cancer. The epigenetic readers of acetylated histones bromodomain and extra-terminal (BET) proteins are critical regulators of gene expression. In cancer, they can upregulate transcription of key oncogenes such as cMYC, IRF4, and BCL-2. In addition, the activity of these proteins can regulate the expression of osteoclastogenic cytokines during cancer progression. Here, we investigated the effect of BET bromodomain protein inhibition, on the expression of NK cell-activating ligands in MM cells. Five MM cell lines [SKO-007(J3), U266, RPMI-8226, ARP-1, JJN3] and CD138 + MM cells isolated from MM patients were used to investigate the activity of BET bromodomain inhibitors (BETi) (JQ1 and I-BET151) and of the selective BRD4-degrader proteolysis targeting chimera (PROTAC) (ARV-825), on the expression and function of several NK cell-activating ligands (NKG2DLs and DNAM-1Ls), using flow cytometry, real-time PCR, transient transfections, and degranulation assays. Our results indicate that inhibition of BET proteins via small molecule inhibitors or their degradation via a hetero-bifunctional PROTAC probe can enhance the expression of MICA, a ligand of the NKG2D receptor, in human MM cell lines and primary malignant plasma cells, rendering myeloma cells more efficient to activate NK cell degranulation. Noteworthy, similar results were obtained using selective CBP/EP300 bromodomain inhibition. Mechanistically, we found that BETi-mediated inhibition of cMYC correlates with the upregulation of miR-125b-5p and the downregulation of the cMYC/miR-125b-5p target gene IRF4, a transcriptional repressor of MICA. These findings provide new insights on the immuno-mediated antitumor activities of BETi and further elucidate the molecular mechanisms that regulate NK cell-activating ligand expression in MM.

Restoration of Immune Surveillance in Lung Cancer by Natural Killer Cells

DTIC Science & Technology

2016-10-01

and had no dramatic effects on NK cell, unlike TGFb, although this product had been effective in the past. However, the pathway that Nicotine and... effects of nicotine on NK function in vivo in smokers and have proceeded to conduct the clinical protocol in Aim 2. Aim 2. To verify that use of...molecule, DAP12, that controls tumoricidal function in human Natural Killer (NK) Cells and to understand how nicotine , contained in tobacco smoke

Natural killer cells promote tissue injury and systemic inflammatory responses during fatal Ehrlichia-induced toxic shock-like syndrome.

PubMed

Stevenson, Heather L; Estes, Mark D; Thirumalapura, Nagaraja R; Walker, David H; Ismail, Nahed

2010-08-01

Human monocytotropic ehrlichiosis is caused by Ehrlichia chaffeensis, a Gram-negative bacterium lacking lipopolysaccharide. We have shown that fatal murine ehrlichiosis is associated with CD8(+)T cell-mediated tissue damage, tumor necrosis factor-alpha, and interleukin (IL)-10 overproduction, and CD4(+)Th1 hyporesponsiveness. In this study, we examined the relative contributions of natural killer (NK) and NKT cells in Ehrlichia-induced toxic shock. Lethal ehrlichial infection in wild-type mice induced a decline in NKT cell numbers, and late expansion and migration of activated NK cells to the liver, a main infection site that coincided with development of hepatic injury. The spatial and temporal changes in NK and NKT cells in lethally infected mice correlated with higher NK cell cytotoxic activity, higher expression of cytotoxic molecules such as granzyme B, higher production of interferon-gamma and tumor necrosis factor-alpha, increased hepatic infiltration with CD8alphaCD11c(+) dendritic cells and CD8(+)T cells, decreased splenic CD4(+)T cells, increased serum concentrations of IL-12p40, IL-18, RANTES, and monocyte chemotactic protein-1, and elevated production of IL-18 by liver mononuclear cells compared with nonlethally infected mice. Depletion of NK cells prevented development of severe liver injury, decreased serum levels of interferon-gamma, tumor necrosis factor-alpha, and IL-10, and enhanced bacterial elimination. These data indicate that NK cells promote immunopathology and defective anti-ehrlichial immunity, possibly via decreasing the protective immune response mediated by interferon-gamma producing CD4(+)Th1 and NKT cells.

Stage 3 immature human natural killer cells found in secondary lymphoid tissue constitutively and selectively express the TH17 cytokine interleukin-22

PubMed Central

Hughes, Tiffany; Becknell, Brian; McClory, Susan; Briercheck, Edward; Freud, Aharon G.; Zhang, Xiaoli; Mao, Hsiaoyin; Nuovo, Gerard; Yu, Jianhua

2009-01-01

Considerable functional heterogeneity within human natural killer (NK) cells has been revealed through the characterization of distinct NK-cell subsets. Accordingly, a small subset of CD56+NKp44+NK cells, termed NK-22 cells, was recently described within secondary lymphoid tissue (SLT) as IL-22− when resting, with a minor fraction of this population becoming IL-22+ when activated. Here we discover that the vast majority of stage 3 immature NK (iNK) cells in SLT constitutively and selectively express IL-22, a TH17 cytokine important for mucosal immunity, whereas earlier and later stages of NK developmental intermediates do not express IL-22. These iNK cells have a surface phenotype of CD34−CD117+CD161+CD94−, largely lack expression of NKp44 and CD56, and do not produce IFN-γ or possess cytolytic activity. In summary, stage 3 iNK cells are highly enriched for IL-22 and IL-26 messenger RNA, and IL-22 protein production, but do not express IL-17A or IL-17F. PMID:19244159

Antimicrobial activity of bovine NK-lysin-derived peptides on Mycoplasma bovis

USDA-ARS?s Scientific Manuscript database

Antimicrobial peptides (AMPs) are a diverse group of molecules which play an important role in the innate immune response in various organisms, including cattle. Bovine NK-lysins, a type of AMP, have been predominantly found in the granules of cytotoxic T-lymphocytes and NK-cells. Collective results...

Group 1 innate lymphoid cells in Toxoplasma gondii infection.

PubMed

Dunay, I R; Diefenbach, A

2018-02-01

Innate lymphoid cells (ILCs) are a group of lymphocytes that carry out important functions in immunity to infections and in organ homeostasis at epithelial barrier surfaces. ILCs are innate immune cells that provide an early source of cytokines to initiate immune responses against pathogens. Cytotoxic ILCs (i.e. conventional (c)NK cells) and several subsets of helper-like ILCs are the major branches of the ILC family. Conventional NK cells and group 1 ILCs share several characteristics such as surface receptors and the ability to produce IFN-γ upon activation, but they differ in their developmental paths and in their dependence on specific transcription factors. Infection of mice with the intracellular parasite Toxoplasma gondii is followed by a strong Th1-mediated immune response. Previous studies indicate that NK1.1 + cells contribute to the production of IFN-γ and TNF and cytotoxicity during acute T. gondii infection. Upon oral infection, the parasite infects intestinal enterocytes, and within the lamina propria, innate immune responses lead to initial parasite control although the infection disseminates widely and persists long-term in immune privileged sites despite adaptive immunity. Upon parasite entry into the small intestine, during the acute stage, ILC1 produce high levels of IFN-γ and TNF protecting barrier surfaces, thus essentially contributing to early parasite control. We will discuss here the role of innate lymphocytes during T. gondii infection in the context of the only recently appreciated diversity of ILC subsets. © 2018 John Wiley & Sons Ltd.

Different features of Vδ2 T and NK cells in fatal and non-fatal human Ebola infections.

PubMed

Cimini, Eleonora; Viola, Domenico; Cabeza-Cabrerizo, Mar; Romanelli, Antonella; Tumino, Nicola; Sacchi, Alessandra; Bordoni, Veronica; Casetti, Rita; Turchi, Federica; Martini, Federico; Bore, Joseph A; Koundouno, Fara Raymond; Duraffour, Sophie; Michel, Janine; Holm, Tobias; Zekeng, Elsa Gayle; Cowley, Lauren; Garcia Dorival, Isabel; Doerrbecker, Juliane; Hetzelt, Nicole; Baum, Jonathan H J; Portmann, Jasmine; Wölfel, Roman; Gabriel, Martin; Miranda, Osvaldo; Díaz, Graciliano; Díaz, José E; Fleites, Yoel A; Piñeiro, Carlos A; Castro, Carlos M; Koivogui, Lamine; Magassouba, N'Faly; Diallo, Boubacar; Ruibal, Paula; Oestereich, Lisa; Wozniak, David M; Lüdtke, Anja; Becker-Ziaja, Beate; Capobianchi, Maria R; Ippolito, Giuseppe; Carroll, Miles W; Günther, Stephan; Di Caro, Antonino; Muñoz-Fontela, César; Agrati, Chiara

2017-05-01

Human Ebola infection is characterized by a paralysis of the immune system. A signature of αβ T cells in fatal Ebola infection has been recently proposed, while the involvement of innate immune cells in the protection/pathogenesis of Ebola infection is unknown. Aim of this study was to analyze γδ T and NK cells in patients from the Ebola outbreak of 2014-2015 occurred in West Africa, and to assess their association with the clinical outcome. Nineteen Ebola-infected patients were enrolled at the time of admission to the Ebola Treatment Centre in Guinea. Patients were divided in two groups on the basis of the clinical outcome. The analysis was performed by using multiparametric flow cytometry established by the European Mobile Laboratory in the field. A low frequency of Vδ2 T-cells was observed during Ebola infection, independently from the clinical outcome. Moreover, Vδ2 T-cells from Ebola patients massively expressed CD95 apoptotic marker, suggesting the involvement of apoptotic mechanisms in Vδ2 T-cell loss. Interestingly, Vδ2 T-cells from survivors expressed an effector phenotype and presented a lower expression of the CTLA-4 exhaustion marker than fatalities, suggesting a role of effector Vδ2 T-cells in the protection. Furthermore, patients with fatal Ebola infection were characterized by a lower NK cell frequency than patients with non fatal infection. In particular, both CD56bright and CD56dim NK frequency were very low both in fatal and non fatal infections, while a higher frequency of CD56neg NK cells was associated to non-fatal infections. Finally, NK activation and expression of NKp46 and CD158a were independent from clinical outcome. Altogether, the data suggest that both effector Vδ2 T-cells and NK cells may play a role in the complex network of protective response to EBOV infection. Further studies are required to characterize the protective effector functions of Vδ2 and NK cells.

Development and function of human innate immune cells in a humanized mouse model.

PubMed

Rongvaux, Anthony; Willinger, Tim; Martinek, Jan; Strowig, Till; Gearty, Sofia V; Teichmann, Lino L; Saito, Yasuyuki; Marches, Florentina; Halene, Stephanie; Palucka, A Karolina; Manz, Markus G; Flavell, Richard A

2014-04-01

Mice repopulated with human hematopoietic cells are a powerful tool for the study of human hematopoiesis and immune function in vivo. However, existing humanized mouse models cannot support development of human innate immune cells, including myeloid cells and natural killer (NK) cells. Here we describe two mouse strains called MITRG and MISTRG, in which human versions of four genes encoding cytokines important for innate immune cell development are knocked into their respective mouse loci. The human cytokines support the development and function of monocytes, macrophages and NK cells derived from human fetal liver or adult CD34(+) progenitor cells injected into the mice. Human macrophages infiltrated a human tumor xenograft in MITRG and MISTRG mice in a manner resembling that observed in tumors obtained from human patients. This humanized mouse model may be used to model the human immune system in scenarios of health and pathology, and may enable evaluation of therapeutic candidates in an in vivo setting relevant to human physiology.

Menstrual blood closely resembles the uterine immune micro-environment and is clearly distinct from peripheral blood.

PubMed

van der Molen, R G; Schutten, J H F; van Cranenbroek, B; ter Meer, M; Donckers, J; Scholten, R R; van der Heijden, O W H; Spaanderman, M E A; Joosten, I

2014-02-01

Is menstrual blood a suitable source of endometrial derived lymphocytes? Mononuclear cells isolated from menstrual samples (menstrual blood mononuclear cells (MMC)) are clearly distinct from peripheral blood mononuclear cells (PBMC) and show a strong resemblance with biopsy-derived endometrial mononuclear cells. A critical event in the onset of pregnancy is the implantation of the embryo in the uterine wall. The immune cell composition in the endometrium at the time of implantation is considered pivotal for success. Despite advancing knowledge on the composition of the immune cell population in the uterus, the role of endometrial immune cells in reproductive disorders is still not fully resolved, mainly due to the fact that this type of research requires invasive techniques. Here, we collected menstrual fluid and validated this unique non-invasive technique to obtain and study the endometrium-derived immune cells which would be present around the time of implantation. Five healthy non-pregnant females with regular menstruation cycles and not using oral contraceptives collected their menstrual blood using a menstrual cup in five consecutive cycles. Sampling took place over the first 3 days of menses, with 12 h intervals. Peripheral blood samples, taken before and after each menstruation, were obtained for comparative analysis. MMC and PBMC samples were characterized for the different lymphocyte subsets by flow cytometry, with emphasis on NK cells and T cells. Next, the functional capacity of the MMC-derived NK cells was determined by measuring intracellular production of IFN-γ, granzyme B and perforin after culture in the presence of IL-2 and IL-15. In support of their endometrial origin, MMC samples contained the typical composition of mononuclear cells expected of endometrial tissue, were phenotypically similar to the reported phenotype for biopsy-derived endometrial cells, and were distinct from PBMC. Increased percentages of NK cells and decreased percentages of T cells were found in MMC when compared with PBMC from the same female. The MMC-derived NK cells were pre-dominantly CD56(bright)/CD16(-), in contrast to the primarily CD56(dim)/CD16(+) peripheral blood NK cells. MMC-derived NK cells expressed CD103, indicating their mucosal origin. In addition, the pattern of natural cytotoxicity receptor (NCR) expression in MMC-derived NK cells was comparable with that in endometrial biopsy-derived NK cells. Compared with PBMC, the NKp30 expression was decreased, while the percentage of NKp44 positive cells was increased in MMC samples. CXCR3 and CXCR4 were hardly expressed by MMC-derived NK cells, indicating that these cells are not of PBMC origin. NK cells from MMC samples were functional as shown by their capacity to produce IFN-γ, granzyme B and perforin, upon stimulation with IL-2 and IL-15. MMC-derived T cells revealed an increased expression of CD103, CD69 and CXCR4 compared with PBMC-derived T cells. Importantly, MMC collection using a menstrual cup proved highly reliable and reproducible between women and between cycles. Based on the parameters we studied, MMC appear similar to biopsy-derived endometrial mononuclear cells. However, sampling is not done at the exact same time in the menstrual cycle, and thus we cannot exclude some, as yet undetected, differences. Also, it should be considered that for some women, the use of the menstrual cup may be unpleasant. Menstrual blood may be a source of endometrial cells and may create new opportunities to study uterine immunological cells in fertility issues. No external funding was obtained for the present study. None of the authors have any conflict of interest to declare. NA.

The effect of Echinococcus granulosus on spleen cells and TGF-β expression in the peripheral blood of BALB/c mice.

PubMed

Yin, S; Chen, X; Zhang, J; Xu, F; Fang, H; Hou, J; Zhang, X; Wu, X; Chen, X

2017-03-01

Cystic echinococcosis (CE) caused by the cestode Echinococcus granulosus (E. granulosus) is a zoonotic parasitic disease. The effective immune evasion mechanisms of E. granulosus allow it to parasitize its hosts. However, the status of the innate and adaptive immune cells and their contributions to E. granulosus progression remain poorly understood. In this study, we aimed to determine the impact of E. granulosus infection on T cells, NK cell responses and TGF-β expression during the early infection phase in BALB/c mice. In E. granulosus infections, there was an increasing tendency in the percentage of CD4 + CD25 + T cells and CD4 + Foxp3 + T cells and peripheral blood TGF-β levels and relative expression of the Foxp3 gene. Moreover, there were a decreasing tendency in the percentage of NK cells and NK cell cytotoxicity and the expression of NKG2D on NK cells. The TGF-β1/Smad pathway was activated by E. granulosus in mice. Above results can be reversed by the inhibitor SB-525334 (potent activin receptor-like kinase 5 inhibitor). These results suggest that the TGF-β/Smad pathway plays an important role in changes of T-cell or NK cell responses. These results may contribute to revealing the preliminary molecular mechanisms in establishing hydatid infection. © 2017 John Wiley & Sons Ltd.

HPV vaccine stimulates cytotoxic activity of killer dendritic cells and natural killer cells against HPV-positive tumour cells

PubMed Central

Van den Bergh, Johan M J; Guerti, Khadija; Willemen, Yannick; Lion, Eva; Cools, Nathalie; Goossens, Herman; Vorsters, Alex; Van Tendeloo, Viggo F I; Anguille, Sébastien; Van Damme, Pierre; Smits, Evelien L J M

2014-01-01

Cervarix™ is approved as a preventive vaccine against infection with the human papillomavirus (HPV) strains 16 and 18, which are causally related to the development of cervical cancer. We are the first to investigate in vitro the effects of this HPV vaccine on interleukin (IL)-15 dendritic cells (DC) as proxy of a naturally occurring subset of blood DC, and natural killer (NK) cells, two innate immune cell types that play an important role in antitumour immunity. Our results show that exposure of IL-15 DC to the HPV vaccine results in increased expression of phenotypic maturation markers, pro-inflammatory cytokine production and cytotoxic activity against HPV-positive tumour cells. These effects are mediated by the vaccine adjuvant, partly through Toll-like receptor 4 activation. Next, we demonstrate that vaccine-exposed IL-15 DC in turn induce phenotypic activation of NK cells, resulting in a synergistic cytotoxic action against HPV-infected tumour cells. Our study thus identifies a novel mode of action of the HPV vaccine in boosting innate immunity, including killing of HPV-infected cells by DC and NK cells. PMID:24979331

Prospective Study of the Evolution of Blood Lymphoid Immune Parameters during Dacarbazine Chemotherapy in Metastatic and Locally Advanced Melanoma Patients

PubMed Central

Vabres, Pierre; Dalac, Sophie; Jeudy, Geraldine; Bel, Blandine; Apetoh, Lionel; Ghiringhelli, François

2014-01-01

Background The importance of immune responses in the control of melanoma growth is well known. However, the implication of these antitumor immune responses in the efficacy of dacarbazine, a cytotoxic drug classically used in the treatment of melanoma, remains poorly understood in humans. Methods In this prospective observational study, we performed an immunomonitoring of eleven metastatic or locally advanced patients treated with dacarbazine as a first line of treatment. We assessed by flow cytometry lymphoid populations and their activation state; we also isolated NK cells to perform in vitro cytotoxicity tests. Results We found that chemotherapy induces lymphopenia and that a significantly higher numbers of naïve CD4+ T cells and lower proportion of Treg before chemotherapy are associated with disease control after dacarbazine treatment. Interestingly, NK cell cytotoxicity against dacarbazine-pretreated melanoma cells is only observed in NK cells from patients who achieved disease control. Conclusion Together, our data pinpoint that some immune factors could help to predict the response of melanoma patients to dacarbazine. Future larger scale studies are warranted to test their validity as prediction markers. PMID:25170840

Endometrial immune markers are potential predictors of normal fertility and pregnancy after in vitro fertilization.

PubMed

Kofod, Louise; Lindhard, Anette; Bzorek, Michael; Eriksen, Jens Ole; Larsen, Lise Grupe; Hviid, Thomas Vauvert F

2017-09-01

Elucidating immune mechanisms in the endometrium, which lead to the success of implantation and pregnancy, is important in reproductive medicine. Studies of immune cell abundance have shown conflicting results, and the expression and importance of HLA class Ib proteins in pre-implantation endometrium have not yet been investigated. The study population consisted of four subgroups: a hydrosalpinx, a salpingectomy, an unexplained infertility, and a fertile control group. Endometrial samples were collected during the implantation window. Immune markers (CD56 + and CD16 + cells, FoxP3 + Tregs, HLA-G, HLA-F) were quantified in the samples. The outcome of the subsequent IVF treatment was recorded. Increased CD56 + uNK cells and high HLA-G expression served as predictor for successful pregnancy outcome. HLA-F expression was positively correlated with uNK cells, being indirectly predictive for achieving pregnancy. Endometrial uNK cell abundance in the pre-implantation endometrium seems to be important for normal fertility and pregnancy success, and they may be used as clinical markers to predict implantation success in IVF. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Activating PIK3CD mutations impair human cytotoxic lymphocyte differentiation, function and EBV immunity.

PubMed

Edwards, Emily S J; Bier, Julia; Cole, Theresa S; Wong, Melanie; Hsu, Peter; Berglund, Lucinda J; Boztug, Kaan; Lau, Anthony; Gostick, Emma; Price, David A; O'Sullivan, Michael; Meyts, Isabelle; Choo, Sharon; Gray, Paul; Holland, Steven M; Deenick, Elissa K; Uzel, Gulbu; Tangye, Stuart G

2018-05-22

Germline gain-of function (GOF) mutations in PIK3CD, encoding the catalytic p110δ subunit of phosphatidylinositol-3 kinase, result in hyperactivation of the PI3K-AKT-mTOR pathway and underlie a novel inborn error of immunity. Affected individuals exhibit perturbed humoral and cellular immunity, manifesting as recurrent infections, autoimmunity, hepatosplenomegaly, uncontrolled EBV and/or CMV infection, and an increased incidence of B-cell lymphoproliferation and/or lymphoma. Mechanisms underlying disease pathogenesis remain unknown. Understanding the cellular and molecular mechanisms underpinning inefficient surveillance of EBV-infected B cells is required to understand disease in individuals with PIK3CD GOF mutations, identify key molecules required for cell mediated immunity against EBV, and develop immunotherapeutic interventions for the treatment of this as well as other EBV-opathies. We studied the consequences of PIK3CD GOF mutations on the generation, differentiation and function of CD8 + T cells and NK cells, which are implicated in host defense against infection with herpesviruses including EBV. PIK3CD GOF total and EBV-specific CD8 + T cells were skewed towards an effector phenotype, with exaggerated expression of markers associated with premature immunosenescence/exhaustion, and increased susceptibility to re-activation induced cell death. These findings were recapitulated in a novel mouse model of PI3K GOF. NK cells in PIK3CD GOF individuals also exhibited perturbed expression of differentiation-associated molecules. Both CD8 + T cells and NK cells had reduced capacity to kill EBV-infected B cells. PIK3CD GOF B cells had increased expression of CD48, PDL-1/2 and CD70. PIK3CD GOF mutations aberrantly induce exhaustion and/or senescence and impair cytotoxicity of CD8+ T and NK cells. These defects may contribute to clinical features of affected individuals, such as impaired immunity to herpesviruses and tumor surveillance. Copyright © 2018. Published by Elsevier Inc.

CXCR6 marks a novel subset of T-betloEomeshi natural killer cells residing in human liver

PubMed Central

Stegmann, Kerstin A.; Robertson, Francis; Hansi, Navjyot; Gill, Upkar; Pallant, Celeste; Christophides, Theodoros; Pallett, Laura J.; Peppa, Dimitra; Dunn, Claire; Fusai, Giuseppe; Male, Victoria; Davidson, Brian R.; Kennedy, Patrick; Maini, Mala K.

2016-01-01

Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56brightCD16−CD57−), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6− fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bethiEomeslo(CXCR6−) and T-betloEomeshi(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bethiEomeslo, suggesting its lineage was closer to CXCR6− peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-betloEomeshi NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity. PMID:27210614

CXCR6 marks a novel subset of T-bet(lo)Eomes(hi) natural killer cells residing in human liver.

PubMed

Stegmann, Kerstin A; Robertson, Francis; Hansi, Navjyot; Gill, Upkar; Pallant, Celeste; Christophides, Theodoros; Pallett, Laura J; Peppa, Dimitra; Dunn, Claire; Fusai, Giuseppe; Male, Victoria; Davidson, Brian R; Kennedy, Patrick; Maini, Mala K

2016-05-23

Natural killer cells (NK) are highly enriched in the human liver, where they can regulate immunity and immunopathology. We probed them for a liver-resident subset, distinct from conventional bone-marrow-derived NK. CXCR6+ NK were strikingly enriched in healthy and diseased liver compared to blood (p < 0.0001). Human hepatic CXCR6+ NK had an immature phenotype (predominantly CD56(bright)CD16-CD57-), and expressed the tissue-residency marker CD69. CXCR6+ NK produced fewer cytotoxic mediators and pro-inflammatory cytokines than the non-liver-specific CXCR6- fraction. Instead CXCR6+ NK could upregulate TRAIL, a key death ligand in hepatitis pathogenesis. CXCR6 demarcated liver NK into two transcriptionally distinct populations: T-bet(hi)Eomes(lo)(CXCR6-) and T-bet(lo)Eomes(hi)(CXCR6+); the latter was virtually absent in the periphery. The small circulating CXCR6+ subset was predominantly T-bet(hi)Eomes(lo), suggesting its lineage was closer to CXCR6- peripheral than CXCR6+ liver NK. These data reveal a large subset of human liver-resident T-bet(lo)Eomes(hi) NK, distinguished by their surface expression of CXCR6, adapted for hepatic tolerance and inducible anti-viral immunity.

Beyond NK cells: the expanding universe of innate lymphoid cells.

PubMed

Cella, Marina; Miller, Hannah; Song, Christina

2014-01-01

For a long time, natural killer (NK) cells were thought to be the only innate immune lymphoid population capable of responding to invading pathogens under the influence of changing environmental cues. In the last few years, an increasing amount of evidence has shown that a number of different innate lymphoid cell (ILC) populations found at mucosal sites rapidly respond to locally produced cytokines in order to establish or maintain homeostasis. These ILC populations closely mirror the phenotype of adaptive T helper subsets in their repertoire of secreted soluble factors. Early in the immune response, ILCs are responsible for setting the stage to mount an adaptive T cell response that is appropriate for the incoming insult. Here, we review the diversity of ILC subsets and discuss similarities and differences between ILCs and NK cells in function and key transcriptional factors required for their development.

Identification, characterisation and expression analysis of natural killer receptor genes in Chlamydia pecorum infected koalas (Phascolarctos cinereus).

PubMed

Morris, Katrina M; Mathew, Marina; Waugh, Courtney; Ujvari, Beata; Timms, Peter; Polkinghorne, Adam; Belov, Katherine

2015-10-15

Koalas (Phascolarctos cinereus), an iconic Australian marsupial, are being heavily impacted by the spread of Chlamydia pecorum, an obligate intracellular bacterial pathogen. Koalas vary in their response to this pathogen, with some showing no symptoms, while others suffer severe symptoms leading to infertility, blindness or death. Little is known about the pathology of this disease and the immune response against it in this host. Studies have demonstrated that natural killer (NK) cells, key components of the innate immune system, are involved in the immune response to chlamydial infections in humans. These cells can directly lyse cells infected by intracellular pathogens and their ability to recognise these infected cells is mediated through NK receptors on their surface. These are encoded in two regions of the genome, the leukocyte receptor complex (LRC) and the natural killer complex (NKC). These two families evolve rapidly and different repertoires of genes, which have evolved by gene duplication, are seen in different species. In this study we aimed to characterise genes belonging to the NK receptor clusters in the koala by searching available koala transcriptomes using a combination of search methods. We developed a qPCR assay to quantify relative expression of four genes, two encoded within the NK receptor cluster (CLEC1B, CLEC4E) and two known to play a role in NK response to Chalmydia in humans (NCR3, PRF1). We found that the NK receptor repertoire of the koala closely resembles that of the Tasmanian devil, with minimal genes in the NKC, but with lineage specific expansions in the LRC. Additional genes important for NK cell activity, NCR3 and PRF1, were also identified and characterised. In a preliminary study to investigate whether these genes are involved in the koala immune response to infection by its chlamydial pathogen, C. pecorum, we investigated the expression of four genes in koalas with active chlamydia infection, those with past infection and those without infection using qPCR. This analysis revealed that one of these four, CLEC4E, may be upregulated in response to chlamydia infection. We have characterised genes of the NKC and LRC in koalas and have discovered evidence that one of these genes may be upregulated in koalas with chlamydia, suggesting that these receptors may play a role in the immune response of koalas to chlamydia infection.

Determination of the reactivity of cytotoxic immune cells with preimplantation mouse embryos

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ewoldsen, M.A.

1987-01-01

Cytotoxic immune cells were used in an assay, MELIA (mixed embryo leukocyte interaction assay) to test the ability of the cells to kill blastocyst stage embryos. The cytotoxic immune cells generated for use in this study, cytotoxic T lymphocytes (CTLs), natural killer (NK) cells, and lymphokine activated killer (LAK) cells were shown to have phenotypic and cytolytic characteristics similar to those reported by other investigators. The lysis of the blastocysts in the MELIA was determined by measuring the inhibition of blastocoel retention and/or by the inhibition of incorporation of tritiated thymidine (/sup 3/H-TdR) into embryonic DNA. Blastocysts which possess ormore » lack their zonae pellucidae were tested to determine whether the zona pellucida plays an immunoprotective role in preimplantation development. The results indicated that CTLs only lysed embryonic cells when the zona pellucida was absent, but NK and LAK cells lysed embryonic cells whether the zona pellucida was present or absent. The results suggest that the zona pellucida may protect the preimplantation mouse embryo from lysis by CTLs but what protects the embryo from lysis by NK and LAK cells is unclear.« less

IL-12 and IL-15 induce the expression of CXCR6 and CD49a on peripheral natural killer cells.

PubMed

Hydes, Theresa; Noll, Angela; Salinas-Riester, Gabriela; Abuhilal, Mohammed; Armstrong, Thomas; Hamady, Zaed; Primrose, John; Takhar, Arjun; Walter, Lutz; Khakoo, Salim I

2018-03-01

Murine hepatic NK cells exhibit adaptive features, with liver-specific adhesion molecules CXCR6 and CD49a acting as surface markers. We investigated human liver-resident CXCR6+ and CD49a+ NK cells using RNA sequencing, flow cytometry, and functional analysis. We further assessed the role of cytokines in generating NK cells with these phenotypes from the peripheral blood. Hepatic CD49a+ NK cells could be induced using cytokines and produce high quantities of IFNγ and TNFα, in contrast to hepatic CXCR6+ NK cells. RNA sequencing of liver-resident CXCR6+ NK cells confirmed a tolerant immature phenotype with reduced expression of markers associated with maturity and cytotoxicity. Liver-resident double-positive CXCR6 + CD49a+ hepatic NK cells are immature but maintain high expression of Th1 cytokines as observed for single-positive CD49a+ NK cells. We show that stimulation with activating cytokines can readily induce upregulation of both CD49a and CXCR6 on NK cells in the peripheral blood. In particular, IL-12 and IL-15 can generate CXCR6 + CD49a+ NK cells in vitro from NK cells isolated from the peripheral blood, with comparable phenotypic and functional features to liver-resident CD49a+ NK cells, including enhanced IFNγ and NKG2C expression. IL-12 and IL-15 may be key for generating NK cells with a tissue-homing phenotype and strong Th1 cytokine profile in the blood, and links peripheral activation of NK cells with tissue-homing. These findings may have important therapeutic implications for immunotherapy of chronic liver disease. © 2017 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.

Low-dose ionizing radiation induces direct activation of natural killer cells and provides a novel approach for adoptive cellular immunotherapy.

PubMed

Yang, Guozi; Kong, Qingyu; Wang, Guanjun; Jin, Haofan; Zhou, Lei; Yu, Dehai; Niu, Chao; Han, Wei; Li, Wei; Cui, Jiuwei

2014-12-01

Recent evidence indicates that limited availability and cytotoxicity have restricted the development of natural killer (NK) cells in adoptive cellular immunotherapy (ACI). While it has been reported that low-dose ionizing radiation (LDIR) could enhance the immune response in animal studies, the influence of LDIR at the cellular level has been less well defined. In this study, the authors aim to investigate the direct effects of LDIR on NK cells and the potential mechanism, and explore the application of activation and expansion of NK cells by LDIR in ACI. The authors found that expansion and cytotoxicity of NK cells were markedly augmented by LDIR. The levels of IFN-γ and TNF-α in the supernatants of cultured NK cells were significantly increased after LDIR. Additionally, the effect of the P38 inhibitor (SB203580) significantly decreased the expanded NK cell cytotoxicity, cytokine levels, and expression levels of FasL and perforin. These findings indicate that LDIR induces a direct expansion and activation of NK cells through possibly the P38-MAPK pathway, which provides a potential mechanism for stimulation of NK cells by LDIR and a novel but simplified approach for ACI.

Differential effects of Denileukin Diftitox IL-2 immunotoxin on NK and regulatory T cells in non-human primates

PubMed Central

Yamada, Yohei; Aoyama, Akihiro; Tocco, Georges; Boskovic, Svjetlan; Nadazdin, Ognjenka; Alessandrini, Alessandro; Madsen, Joren C.; Cosimi, A. Benedict; Benichou, Gilles; Kawai, Tatsuo

2012-01-01

Denileukin Diftitox (DD), a fusion protein comprised of IL-2 and diphtheria toxin was initially expected to enhance anti-tumor immunity by selectively eliminating regulatory T cells (Tregs) displaying the high affinity IL-2R (α-β-γ trimers). While DD has been shown to deplete some Tregs in primates, its effects on NK cells (CD16+CD8+NKG2A+CD3−), which constitutively express the intermediate affinity IL-2R (β-γ dimers) and play a critical role in anti-tumor immunity, are still unknown. To address this question, cynomolgus monkeys were injected intravenously with two different doses of DD (8 or 18 μg/Kg). This treatment resulted in a rapid but short-term reduction in detectable peripheral blood resting Tregs (R-Tregs: CD4+CD45RA+Foxp3+) and a transient increase in the number of activated Tregs (A-Tregs: CD4+CD45RA−Foxp3high) followed by their partial depletion (50–60%). On the other hand, all NK cells were deleted immediately and durably after DD administration. This difference was not due to a higher binding or internalization of DD by NK cells as compared to Tregs. Co-administration of DD with IL-15, which binds to IL-2Rβ-γ, abrogated DD-induced NK cell deletion in vitro and in vivo while it did not affect Tregs elimination. Taken together, these results show that DD exerts a potent cytotoxic effect on NK cells, a phenomenon which might impair its anti-tumoral properties. However, co-administration of IL-15 with DD could alleviate this problem by selectively protecting potentially oncolytic NK cells while allowing the depletion of immunosuppressive regulatory T cells in cancer patients. PMID:22586034

Requirement for Innate Immunity and CD90+ NK1.1− Lymphocytes to Treat Established Melanoma with Chemo-Immunotherapy

PubMed Central

Moskalenko, Marina; Pan, Michael; Fu, Yichun; de Moll, Ellen H.; Hashimoto, Daigo; Mortha, Arthur; Leboeuf, Marylene; Jayaraman, Padmini; Bernardo, Sebastian; Sikora, Andrew G.; Wolchok, Jedd; Bhardwaj, Nina; Merad, Miriam; Saenger, Yvonne

2015-01-01

We sought to define cellular immune mechanisms of synergy between tumor-antigen–targeted monoclonal antibodies and chemotherapy. Established B16 melanoma in mice was treated with cytotoxic doses of cyclophosphamide in combination with an antibody targeting tyrosinase-related protein 1 (αTRP1), a native melanoma differentiation antigen. We find that Fcγ receptors are required for efficacy, showing that antitumor activity of combination therapy is immune mediated. Rag1−/− mice deficient in adaptive immunity are able to clear tumors, and thus innate immunity is sufficient for efficacy. Furthermore, previously treated wild-type mice are not significantly protected against tumor reinduction, as compared with mice inoculated with irradiated B16 alone, consistent with a primarily innate immune mechanism of action of chemo-immunotherapy. In contrast, mice deficient in both classical natural killer (NK) lymphocytes and nonclassical innate lymphocytes (ILC) due to deletion of the IL2 receptor common gamma chain IL2γc−/−) are refractory to chemo-immunotherapy. Classical NK lymphocytes are not critical for treatment, as depletion of NK1.1+ cells does not impair antitumor effect. Depletion of CD90+NK1.1− lymphocytes, however, both diminishes therapeutic benefit and decreases accumulation of macrophages within the tumor. Tumor clearance during combination chemo-immunotherapy with monoclonal antibodies against native antigen is mediated by the innate immune system. We highlight a novel potential role for CD90+NK1.1− ILCs in chemo-immunotherapy. PMID:25600438

The E3 ligase Cbl-b and TAM receptors regulate cancer metastasis via natural killer cells.

PubMed

Paolino, Magdalena; Choidas, Axel; Wallner, Stephanie; Pranjic, Blanka; Uribesalgo, Iris; Loeser, Stefanie; Jamieson, Amanda M; Langdon, Wallace Y; Ikeda, Fumiyo; Fededa, Juan Pablo; Cronin, Shane J; Nitsch, Roberto; Schultz-Fademrecht, Carsten; Eickhoff, Jan; Menninger, Sascha; Unger, Anke; Torka, Robert; Gruber, Thomas; Hinterleitner, Reinhard; Baier, Gottfried; Wolf, Dominik; Ullrich, Axel; Klebl, Bert M; Penninger, Josef M

2014-03-27

Tumour metastasis is the primary cause of mortality in cancer patients and remains the key challenge for cancer therapy. New therapeutic approaches to block inhibitory pathways of the immune system have renewed hopes for the utility of such therapies. Here we show that genetic deletion of the E3 ubiquitin ligase Cbl-b (casitas B-lineage lymphoma-b) or targeted inactivation of its E3 ligase activity licenses natural killer (NK) cells to spontaneously reject metastatic tumours. The TAM tyrosine kinase receptors Tyro3, Axl and Mer (also known as Mertk) were identified as ubiquitylation substrates for Cbl-b. Treatment of wild-type NK cells with a newly developed small molecule TAM kinase inhibitor conferred therapeutic potential, efficiently enhancing anti-metastatic NK cell activity in vivo. Oral or intraperitoneal administration using this TAM inhibitor markedly reduced murine mammary cancer and melanoma metastases dependent on NK cells. We further report that the anticoagulant warfarin exerts anti-metastatic activity in mice via Cbl-b/TAM receptors in NK cells, providing a molecular explanation for a 50-year-old puzzle in cancer biology. This novel TAM/Cbl-b inhibitory pathway shows that it might be possible to develop a 'pill' that awakens the innate immune system to kill cancer metastases.

The role of NK cells in HIV-1 protection: autologous, allogeneic or both?

PubMed

Hens, Jef; Jennes, Wim; Kestens, Luc

2016-01-01

Natural killer (NK) cells specialize in killing virally infected- or tumor cells and are part of the innate immune system. The activational state of NK cells is determined by the balance of incoming activating and inhibitory signals mediated by receptor-ligand binding with the target cell. These receptor-ligand bonds mainly consist of the killer immunoglobulin-like receptors (KIR), which are expressed at the cell surface of NK cells, and their ligands: the highly variable human leukocyte antigen -class I molecules (HLA). Absence of an inhibitory receptor-ligand bond lowers the NK cell activation threshold, whereas an activating receptor-ligand bond stimulates the cell, potentially overcoming this threshold and triggering NK cell activation. NK cells influence the course of infection as well as the acquisition of HIV-1. Several lines of evidence relate the activating NK cell receptor KIR3DS1, in the presence or absence of its putative ligand HLA-Bw4, with slower disease progression as well as resistance to HIV-1 infection. Overall, resistance to HIV-1 infection predominantly correlates with activating KIR/HLA profiles, consisting of e.g. activating KIRs, group B haplotypes, or inhibitory KIRs in absence of their ligands. Such a conclusion is less evident for studies of HIV-1 disease progression, with studies reporting beneficial as well as detrimental effects of activating KIR/HLA genotypes. It is likely that KIR/HLA association studies are complicated by the complexity of the KIR and HLA loci and their mutual interactions, as well as by additional factors like route of HIV exposure, immune activation, presence of co-infections, and the effect of anti-HIV-1 antibodies. One newly discovered NK cell activation pathway associated with resistance to HIV-1 infection involves the presence of an iKIR/HLA mismatch between partners. The absence of such an iKIR/HLA bond renders donor-derived allogeneic HIV-1 infected cells vulnerable to NK cell responses during HIV-1 transmission. Therefore, theoretically, HIV-1 would be eliminated before it has the chance to infect the autologous cells in the recipient. While this "alloreactive" NK cell mechanism is especially relevant to HIV transmission in monogamous couples, it would be interesting to investigate how it could influence resistance to HIV in other settings. The objective of this review is to summarize the knowledge about these autologous and alloreactive NK cell responses with regard to HIV-1 outcome.

Improving efficacy of cancer immunotherapy by genetic modification of natural killer cells.

PubMed

Burga, Rachel A; Nguyen, Tuongvan; Zulovich, Jane; Madonna, Sarah; Ylisastigui, Loyda; Fernandes, Rohan; Yvon, Eric

2016-11-01

Natural killer (NK) cells are members of the innate immune system that recognize target cells via activating and inhibitory signals received through cell receptors. Derived from the lymphoid lineage, NK cells are able to produce cytokines and exert a cytotoxic effect on viral infected and malignant cells. It is their unique ability to lyse target cells rapidly and without prior education that renders NK cells a promising effector cell for adoptive cell therapy. However, both viruses and tumors employ evasion strategies to avoid attack by NK cells, which represent biological challenges that need to be harnessed to fully exploit the cytolytic potential of NK cells. Using genetic modification, the function of NK cells can be enhanced to improve their homing, cytolytic activity, in vivo persistence and safety. Examples include gene modification to express chemokine, high-affinity Fc receptor and chimeric antigen receptors, suicide genes and the forced expression of cytokines such as interleukin (IL)-2 and IL-15. Preclinical studies have clearly demonstrated that such approaches are effective in improving NK-cell function, homing and safety. In this review, we summarize the recent advances in the genetic manipulations of NK cells and their application for cellular immunotherapeutic strategies. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Innate lymphoid cells and the MHC.

PubMed

Robinette, M L; Colonna, M

2016-01-01

Innate lymphoid cells (ILCs) are a new class of immune cells that include natural killer (NK) cells and appear to be the innate counterparts to CD4(+) helper T cells and CD8(+) cytotoxic T cells based on developmental and functional similarities. Like T cells, both NK cells and other ILCs also show connections to the major histocompatibility complex (MHC). In human and mouse, NK cells recognize and respond to classical and nonclassical MHC I molecules as well as structural homologues, whereas mouse ILCs have recently been shown to express MHC II. We describe the history of MHC I recognition by NK cells and discuss emerging roles for MHC II expression by ILC subsets, making comparisons between both mouse and human when possible. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Immunological abnormalities as potential biomarkers in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis.

PubMed

Brenu, Ekua W; van Driel, Mieke L; Staines, Don R; Ashton, Kevin J; Ramos, Sandra B; Keane, James; Klimas, Nancy G; Marshall-Gradisnik, Sonya M

2011-05-28

Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is characterised by severe prolonged fatigue, and decreases in cognition and other physiological functions, resulting in severe loss of quality of life, difficult clinical management and high costs to the health care system. To date there is no proven pathomechanism to satisfactorily explain this disorder. Studies have identified abnormalities in immune function but these data are inconsistent. We investigated the profile of markers of immune function (including novel markers) in CFS/ME patients. We included 95 CFS/ME patients and 50 healthy controls. All participants were assessed on natural killer (NK) and CD8(+) T cell cytotoxic activities, Th1 and Th2 cytokine profile of CD4(+) T cells, expression of vasoactive intestinal peptide receptor 2 (VPACR2), levels of NK phenotypes (CD56(bright) and CD56(dim)) and regulatory T cells expressing FoxP3 transcription factor. Compared to healthy individuals, CFS/ME patients displayed significant increases in IL-10, IFN-γ, TNF-α, CD4(+)CD25(+) T cells, FoxP3 and VPACR2 expression. Cytotoxic activity of NK and CD8(+) T cells and NK phenotypes, in particular the CD56(bright) NK cells were significantly decreased in CFS/ME patients. Additionally granzyme A and granzyme K expression were reduced while expression levels of perforin were significantly increased in the CFS/ME population relative to the control population. These data suggest significant dysregulation of the immune system in CFS/ME patients. Our study found immunological abnormalities which may serve as biomarkers in CFS/ME patients with potential for an application as a diagnostic tool.

Sphingosine kinase inhibitor suppresses IL-18-induced interferon-gamma production through inhibition of p38 MAPK activation in human NK cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheon, Soyoung; Song, Seok Bean; Jung, Minkyung

2008-09-12

Natural killer (NK) cells play an important role in the innate immune response. Interleukin-18 (IL-18) is a well-known interferon-gamma (IFN-{gamma} inducing factor, which stimulates immune response in NK and T cells. Sphingosine kinase (SPHK) catalyzes the formation of sphingosine 1-phosphate (S1P), which acts as a second messenger to function as an anti-apoptotic factor and proliferation stimulator of immune cells. In this study, to elucidate whether SPHK is involved in IL-18-induced IFN-{gamma} production, we measured IL-18-induced IFN-{gamma} production after pre-treatment with SPHK inhibitor (SKI) in NK-92MI cells. We found that IL-18-induced IFN-{gamma} expression was blocked by SKI pre-treatment in both mRNAmore » and protein levels. In addition, the increased IFN-{gamma} production by stimulation with IL-18 is mediated through both SPHK and p38 MAPK. To determine the upstream signals of SKI and p38 MAPK in IL-18-induced IFN-{gamma} production, phosphorylation levels of p38 MAPK was measured after SKI pre-treatment. As a result, inhibition of SPHK by SKI blocked phosphorylation of p38 MAPK, showing that SPHK activation by IL-18 is an upstream signal of p38 MAPK activation. Inhibition of SPHK by SKI also inhibited IL-18-induced IFN-{gamma} production in human primary NK cells. In conclusion, SPHK activation is an essential factor for IL-18-induced IFN-{gamma} production via p38 MAPK.« less

[Immune diagnostics of disorders in the IFN-alpha/NK-cell system in patients with frequently recurrent herpes simplex].

PubMed

Karsonova, A V; Shulzhenko, A E; Karaulov, A V

2014-01-01

Study of features of NK-cell response to the effect of recombinant IFN-alpha in complex with evaluation of the ability to synthesize inherent IFN-alpha in patients with frequently recurrent herpes simplex (FRHS). 48 patients with genital (n = 31), labial (n = 10) and mixed localization (n = 7) FRHS diagnosis were observed. 31 healthy donors composed the control group. MC were cultivated in the presence of a recombinant human IFN-alpha2b at the concentration of 10, 100 and 1000 U/ml for 24 hours. NK-cell response to the effect of IFN-alpha was evaluated after 24 hours using flow cytometry by degranulation reaction and in the NK-activity test. IFN-alpha synthesis was evaluated in HSV-1, HSV-2 and Newcastle disease virus stimulated cell supernatants by EIA method. Patients with FRHS were established to be a heterogeneous group by parameters in the IFN-alpha/NK-cell cytotoxicity system. 2 types of NK-cell response to the stimulation by recombinant IFN-alpha were identified. Type A is characterized by a decrease of NK-cell response to IFN-alpha in the remission phase and does not have this defect in the exacerbation phase. Synthesis of inherent IFN-alpha in response to viral inductors for type A was comparable with the response in healthy donors in both phases. On the contrary type B having normal sensitivity of NK-cells to IFN-alpha in the remission phase is characterized by a decrease of this parameter in the exacerbation phase for more than 3 times. Synthesis of inherent IFN-alpha in response to viral inductors during type B is increased in the remission phase and decreased in the exacerbation phase. During immune-correcting therapy of FRHS a personalized approach taking into account features of NK-cell response to IFN-alpha is necessary, because types A and B have principal differences by cytotoxicity parameters of NK-cells and their change under the effect of IFN-alpha, as well as by parameters of IFN-alpha synthesis in response to viral inductors at various phases of the clinical process.

RB mutation and RAS overexpression induce resistance to NK cell-mediated cytotoxicity in glioma cells.

PubMed

Orozco-Morales, Mario; Sánchez-García, Francisco Javier; Golán-Cancela, Irene; Hernández-Pedro, Norma; Costoya, Jose A; de la Cruz, Verónica Pérez; Moreno-Jiménez, Sergio; Sotelo, Julio; Pineda, Benjamín

2015-01-01

Several theories aim to explain the malignant transformation of cells, including the mutation of tumor suppressors and proto-oncogenes. Deletion of Rb (a tumor suppressor), overexpression of mutated Ras (a proto-oncogene), or both, are sufficient for in vitro gliomagenesis, and these genetic traits are associated with their proliferative capacity. An emerging hallmark of cancer is the ability of tumor cells to evade the immune system. Whether specific mutations are related with this, remains to be analyzed. To address this issue, three transformed glioma cell lines were obtained (Rb(-/-), Ras(V12), and Rb(-/-)/Ras(V12)) by in vitro retroviral transformation of astrocytes, as previously reported. In addition, Ras(V12) and Rb(-/-)/Ras(V12) transformed cells were injected into SCID mice and after tumor growth two stable glioma cell lines were derived. All these cells were characterized in terms of Rb and Ras gene expression, morphology, proliferative capacity, expression of MHC I, Rae1δ, and Rae1αβγδε, mult1, H60a, H60b, H60c, as ligands for NK cell receptors, and their susceptibility to NK cell-mediated cytotoxicity. Our results show that transformation of astrocytes (Rb loss, Ras overexpression, or both) induced phenotypical and functional changes associated with resistance to NK cell-mediated cytotoxicity. Moreover, the transfer of cell lines of transformed astrocytes into SCID mice increased resistance to NK cell-mediated cytotoxicity, thus suggesting that specific changes in a tumor suppressor (Rb) and a proto-oncogene (Ras) are enough to confer resistance to NK cell-mediated cytotoxicity in glioma cells and therefore provide some insight into the ability of tumor cells to evade immune responses.

NKp44 receptor mediates interaction of the envelope glycoproteins from the West-Nile and dengue viruses with Natural Killer cells

PubMed Central

Hershkovitz, Oren; Rosental, Benyamin; Rosenberg, Lior Ann; Navarro-Sanchez, Martha Erika; Jivov, Sergey; Zilka, Alon; Gershoni-Yahalom, Orly; Brient-Litzler, Elodie; Bedouelle, Hugues; Ho, Joanna W.; Campbell, Kerry S.; Rager-Zisman, Bracha; Despres, Philippe; Porgador, Angel

2009-01-01

Dengue virus (DV) and West Nile virus (WNV) have become a global concern due to their widespread distribution and their ability to cause a variety of human diseases. Antiviral immune defenses involve natural killer (NK) cells. In the present study, we investigated the interaction between NK cells and these two flaviviruses. We show that the NK-activating receptor NKp44 is involved in virally-mediated NK activation through direct interaction with the flavivirus envelope protein. Recombinant NKp44 directly binds to purified DV and WNV envelope proteins and specifically to domain III of WNV envelope protein (EIII); it also binds to WNV virus-like particles (VLPs). These WNV-VLPs and WNV-EIII directly bind NK cells expressing high levels of NKp44. Functionally, interaction of NK cells with infective and inactivated WNV results in NKp44-mediated NK de-granulation. Finally, WNV infection of cells results in increased binding of recombinant NKp44 that is specifically inhibited by anti-WNV serum. WNV-infected target cells induce IFNγ secretion and augmented lysis by NKp44-expressing primary NK cells that are blocked by anti-NKp44 antibodies. Our findings show that triggering of NK cells by flavivirus is mediated by interaction of NKp44 with the flavivirus envelope protein. PMID:19635919

Long-lasting memory of cellular immunity in a chronic myeloid leukemia patient maintains molecular response 5 after cessation of dasatinib

PubMed Central

Jo, Tatsuro; Noguchi, Kazuhiro; Hayashi, Shizuka; Irie, Sadaharu; Hayase, Risa; Shioya, Haruna; Kaneko, Youhei; Horio, Kensuke; Taguchi, Jun

2018-01-01

Tyrosine kinase inhibitors (TKIs), including imatinib, dasatinib and nilotinib are primarily used in the initial treatment of chronic phase (CP)-chronic myeloid leukemia (CML), as CMLs harbor the BCR-ABL fusion product. An increased number of lymphocytes and large granular lymphocytes (LGLs) have been observed in patients treated with dasatinib, but not other TKIs. The LGLs have been reported to be primarily natural killer (NK) cells and cytotoxic T lymphocytes (CTLs). In the present study, a CP-CML patient who has maintained molecular response 5 for >2.4 years after stopping dasatinib was reported. Memory and effector CTLs and NK cells, were observed after 2.4 years of treatment-free remission, despite the fact that lymphocyte counts are not elevated in the patient. These results suggest that dasatinib may induce cellular immunity, including NK cells and CTLs and this cellular immunity may be maintained for a long period following cessation of dasatinib. The results suggest that this cellular immunity may provide a long-term cure without the need for continued TKI treatment. PMID:29435021

Thy1+ Nk Cells from Vaccinia Virus-Primed Mice Confer Protection against Vaccinia Virus Challenge in the Absence of Adaptive Lymphocytes

PubMed Central

Gillard, Geoffrey O.; Bivas-Benita, Maytal; Hovav, Avi-Hai; Grandpre, Lauren E.; Panas, Michael W.; Seaman, Michael S.; Haynes, Barton F.; Letvin, Norman L.

2011-01-01

While immunological memory has long been considered the province of T- and B- lymphocytes, it has recently been reported that innate cell populations are capable of mediating memory responses. We now show that an innate memory immune response is generated in mice following infection with vaccinia virus, a poxvirus for which no cognate germline-encoded receptor has been identified. This immune response results in viral clearance in the absence of classical adaptive T and B lymphocyte populations, and is mediated by a Thy1+ subset of natural killer (NK) cells. We demonstrate that immune protection against infection from a lethal dose of virus can be adoptively transferred with memory hepatic Thy1+ NK cells that were primed with live virus. Our results also indicate that, like classical immunological memory, stronger innate memory responses form in response to priming with live virus than a highly attenuated vector. These results demonstrate that a defined innate memory cell population alone can provide host protection against a lethal systemic infection through viral clearance. PMID:21829360

The ectromelia virus SPI-2 protein causes lethal mousepox by preventing NK cell responses.

PubMed

Melo-Silva, Carolina R; Tscharke, David C; Lobigs, Mario; Koskinen, Aulikki; Wong, Yik Chun; Buller, R Mark; Müllbacher, Arno; Regner, Matthias

2011-11-01

Ectromelia virus (ECTV) is a natural pathogen of mice that causes mousepox, and many of its genes have been implicated in the modulation of host immune responses. Serine protease inhibitor 2 (SPI-2) is one of these putative ECTV host response modifier proteins. SPI-2 is conserved across orthopoxviruses, but results defining its mechanism of action and in vivo function are lacking or contradictory. We studied the role of SPI-2 in mousepox by deleting the SPI-2 gene or its serine protease inhibitor reactive site. We found that SPI-2 does not affect viral replication or cell-intrinsic apoptosis pathways, since mutant viruses replicate in vitro as efficiently as wild-type virus. However, in the absence of SPI-2 protein, ECTV is attenuated in mousepox-susceptible mice, resulting in lower viral loads in the liver, decreased spleen pathology, and substantially improved host survival. This attenuation correlates with more effective immune responses in the absence of SPI-2, including an earlier serum gamma interferon (IFN-γ) response, raised serum interleukin 18 (IL-18), increased numbers of granzyme B(+) CD8(+) T cells, and, most notably, increased numbers and activation of NK cells. Both virus attenuation and the improved immune responses associated with SPI-2 deletion from ECTV are lost when mice are depleted of NK cells. Consequently, SPI-2 renders mousepox lethal in susceptible strains by preventing protective NK cell defenses.

The biology of NK cells and their receptors affects clinical outcomes after hematopoietic cell transplantation (HCT).

PubMed

Foley, Bree; Felices, Martin; Cichocki, Frank; Cooley, Sarah; Verneris, Michael R; Miller, Jeffrey S

2014-03-01

Natural killer (NK) cells were first identified for their capacity to reject bone marrow allografts in lethally irradiated mice without prior sensitization. Subsequently, human NK cells were detected and defined by their non-major histocompatibility complex (MHC)-restricted cytotoxicity toward transformed or virally infected target cells. Karre et al. later proposed 'the missing self hypothesis' to explain the mechanism by which self-tolerant cells could kill targets that had lost self MHC class I. Subsequently, the receptors that recognize MHC class I to mediate tolerance in the host were identified on NK cells. These class I-recognizing receptors contribute to the acquisition of function by a dynamic process known as NK cell education or licensing. In the past, NK cells were assumed to be short lived, but more recently NK cells have been shown to mediate immunologic memory to secondary exposures to cytomegalovirus infection. Because of their ability to lyse tumors with aberrant MHC class I expression and to produce cytokines and chemokines upon activation, NK cells may be primed by many stimuli, including viruses and inflammation, to contribute to a graft-versus-tumor effect. In addition, interactions with other immune cells support the therapeutic potential of NK cells to eradicate tumor and to enhance outcomes after hematopoietic cell transplantation. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

The evolution of the natural killer complex; a comparison between mammals using new high-quality genome assemblies and targeted annotation

USDA-ARS?s Scientific Manuscript database

Natural killer (NK) cells are a diverse population of lymphocytes with a range of biological roles including essential immune functions. NK cell diversity is created by the differential expression of cell surface receptors which modulate activation and function, including multiple subfamilies of C-t...

[Immune regulation activity and mechanism of Tibetan Kefir exopolysaccharide fractions].

PubMed

Meng, Li; Zhang, Lanwei

2009-12-01

To investigate the effects and mechanism on immune regulation activity in mice of two Tibetan Kefir exoploysaccharides (EPS) with different molecular weight of 0.1 x 10(5) - 3 x 10(5) (fraction 1) and 1.8 x 10(3) (fraction 2). The immune regulation activity experiment was carried out in vitro based on the Functional Assessment Procedure and Test Methods of Health Food, which was issued by Ministry of Health of China. First, we treated mice subjects with EPS at doses of 40 mg/kg, 80 mg/kg, 120 mg/kg through ig. Then we detected the index of immune organs, the ability of antibody production (tested by HC50), activity of NK cell, delayed type hypersensitivity (DTH) and phagocytosis of macrophage in mice. Finally, we examined the expression of Erk protein in Macrophages by Western Blot assay. Fraction 1 could promote HC50, activity of NK cell and DTH in mice which low dose showed better. Fraction 2 could promote DTH, phagocytosis of macrophage which high dose showed better. The expression of Erk and COX-2 had the same trend with Phagocytic index. We verified the two fractions of Tibetan Kefir EPS could enhance immune functions in mice. Fraction 1 regulated immune function through NK cell and B cell while fraction 2 through macrophage cell and T cell. The effects to macrophage of Tibetan Kefir EPS in mice may realize through extra cellular signal-regulated kinase Erk pathway.

Interferon-γ production by tubulointerstitial human CD56bright natural killer cells contributes to renal fibrosis and chronic kidney disease progression.

PubMed

Law, Becker M P; Wilkinson, Ray; Wang, Xiangju; Kildey, Katrina; Lindner, Mae; Rist, Melissa J; Beagley, Kenneth; Healy, Helen; Kassianos, Andrew J

2017-07-01

Natural killer (NK) cells are a population of lymphoid cells that play a significant role in mediating innate immune responses. Studies in mice suggest a pathological role for NK cells in models of kidney disease. In this study, we characterized the NK cell subsets present in native kidneys of patients with tubulointerstitial fibrosis, the pathological hallmark of chronic kidney disease. Significantly higher numbers of total NK cells (CD3 - CD56 + ) were detected in renal biopsies with tubulointerstitial fibrosis compared with diseased biopsies without fibrosis and healthy kidney tissue using multi-color flow cytometry. At a subset level, both the CD56 dim NK cell subset and particularly the CD56 bright NK cell subset were elevated in fibrotic kidney tissue. However, only CD56 bright NK cells significantly correlated with the loss of kidney function. Expression of the tissue-retention and -activation molecule CD69 on CD56 bright NK cells was significantly increased in fibrotic biopsy specimens compared with non-fibrotic kidney tissue, indicative of a pathogenic phenotype. Further flow cytometric phenotyping revealed selective co-expression of activating receptor CD335 (NKp46) and differentiation marker CD117 (c-kit) on CD56 bright NK cells. Multi-color immunofluorescent staining of fibrotic kidney tissue localized the accumulation of NK cells within the tubulointerstitium, with CD56 bright NK cells (NKp46 + CD117 + ) identified as the source of pro-inflammatory cytokine interferon-γ within the NK cell compartment. Thus, activated interferon-γ-producing CD56 bright NK cells are positioned to play a key role in the fibrotic process and progression to chronic kidney disease. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

The type of ATG matters -- natural killer cells are influenced differentially by Thymoglobulin, Lymphoglobulin and ATG-Fresenius.

PubMed

Penack, Olaf; Fischer, Lars; Gentilini, Chiara; Nogai, Axel; Muessig, Arne; Rieger, Kathrin; Ganepola, Susanne; Thiel, Eckhard; Uharek, Lutz

2007-11-01

Although ATG is frequently used in hematopoietic stem cell transplantation and solid organ transplantation, little is known on its effects on NK cells, which mediate important functions in post-transplantation immunology. We incubated peripheral blood lymphocytes of healthy donors with Thymoglobulin, Lymphoglobulin or ATG-Fresenius. Cell death and apoptosis of NK cells and T cells were determined by flow cytometry using propidium iodide and Annexin V. As expected, there were no significant differences between the different ATGs regarding their T cell toxicity. Surprisingly, we found profound differences between the different ATGs regarding their impact on NK cells: In clinically relevant concentrations Lymphoglobulin had less toxic effects on NK cells as compared to Thymoglobulin or ATG-Fresenius: the median percentages of apoptotic or necrotic NK cells in response to 1 mug/ml Lymphoglobulin, ATG-Fresenius and Thymoglobulin were 2%, 35% and 38%, respectively (p<0.001). This is the first report of differential effects of different ATGs on NK cells. Lymphoglobulin appears to be superior to Thymoglobulin or ATG Fresenius regarding the preservation of NK cell mediated immunity. Randomized trials addressing the impact of different ATGs on lymphocyte subpopulations in the clinical setting are urgently warranted.

Chimeric antigen receptor (CAR)-modified natural killer cell-based immunotherapy and immunological synapse formation in cancer and HIV.

PubMed

Liu, Dongfang; Tian, Shuo; Zhang, Kai; Xiong, Wei; Lubaki, Ndongala Michel; Chen, Zhiying; Han, Weidong

2017-12-01

Cytotoxic T lymphocytes (CTLs) and natural killer (NK) cells contribute to the body's immune defenses. Current chimeric antigen receptor (CAR)-modified T cell immunotherapy shows strong promise for treating various cancers and infectious diseases. Although CAR-modified NK cell immunotherapy is rapidly gaining attention, its clinical applications are mainly focused on preclinical investigations using the NK92 cell line. Despite recent advances in CAR-modified T cell immunotherapy, cost and severe toxicity have hindered its widespread use. To alleviate these disadvantages of CAR-modified T cell immunotherapy, additional cytotoxic cell-mediated immunotherapies are urgently needed. The unique biology of NK cells allows them to serve as a safe, effective, alternative immunotherapeutic strategy to CAR-modified T cells in the clinic. While the fundamental mechanisms underlying the cytotoxicity and side effects of CAR-modified T and NK cell immunotherapies remain poorly understood, the formation of the immunological synapse (IS) between CAR-modified T or NK cells and their susceptible target cells is known to be essential. The role of the IS in CAR T and NK cell immunotherapies will allow scientists to harness the power of CAR-modified T and NK cells to treat cancer and infectious diseases. In this review, we highlight the potential applications of CAR-modified NK cells to treat cancer and human immunodeficiency virus (HIV), and discuss the challenges and possible future directions of CAR-modified NK cell immunotherapy, as well as the importance of understanding the molecular mechanisms of CAR-modified T cell- or NK cell-mediated cytotoxicity and side effects, with a focus on the CAR-modified NK cell IS.

Diurnal rhythms in peripheral blood immune cell numbers of domestic pigs.

PubMed

Engert, Larissa C; Weiler, Ulrike; Pfaffinger, Birgit; Stefanski, Volker; Schmucker, Sonja S

2018-02-01

Diurnal rhythms within the immune system are considered important for immune competence. Until now, they were mostly studied in humans and rodents. However, as the domestic pig is regarded as suitable animal model and due to its importance in agriculture, this study aimed to characterize diurnal rhythmicity in porcine circulating leukocyte numbers. Eighteen pigs were studied over periods of up to 50 h. Cosinor analyses revealed diurnal rhythms in cell numbers of most investigated immune cell populations in blood. Whereas T cell, dendritic cell, and eosinophil counts peaked during nighttime, NK cell and neutrophil counts peaked during daytime. Relative amplitudes of cell numbers in blood differed in T helper cell subtypes with distinctive differentiation states. Mixed model analyses revealed that plasma cortisol concentration was negatively associated with cell numbers of most leukocyte types, except for NK cells and neutrophils. The observed rhythms mainly resemble those found in humans and rodents. Copyright © 2017 Elsevier Ltd. All rights reserved.

Herpes simplex virus antigens directly activate NK cells via TLR2, thus facilitating their presentation to CD4 T lymphocytes.

PubMed

Kim, Min; Osborne, Naomi R; Zeng, Weiguang; Donaghy, Heather; McKinnon, Kay; Jackson, David C; Cunningham, Anthony L

2012-05-01

NK cells infiltrate human herpetic lesions, but their role has been underexplored. HSV can stimulate innate immune responses via surface TLR2, which is expressed on monocyte-derived dendritic cells (DCs) and NK cells. In this study, UV-inactivated HSV1/2 and immunodominant HSV2 glycoprotein D peptides conjugated to the TLR2 agonist dipalmitoyl-S-glyceryl cysteine stimulated CD4 T lymphocyte IFN-γ responses within PBMCs or in coculture with monocyte-derived DCs. NK cells contributed markedly to the PBMC responses. Furthermore, NK cells alone were activated directly by both Ags, also upregulating HLA-DR and HLA-DQ and then they activated autologous CD4 T lymphocytes. Using Transwells, Ag-stimulated NK cells and CD4 T lymphocytes were shown to interact through both cell-to-cell contact and cytokines, differing in relative importance in different donors. A distinct immunological synapse between Ag-stimulated NK cells and CD4 T lymphocytes was observed, indicating the significance of their cell-to-cell contact. A large proportion (57%) of NK cells was also in contact with CD4 T lymphocytes in the dermal infiltrate of human recurrent herpetic lesions. Thus, NK cells stimulated by TLR2-activating HSV Ags can present Ag alone or augment the role of DCs in vitro and perhaps in herpetic lesions or draining lymph nodes. In addition to DCs, NK cells should be considered as targets for adjuvants during HSV vaccine development.

Ginseng (Panax ginseng Meyer) oligopeptides regulate innate and adaptive immune responses in mice via increased macrophage phagocytosis capacity, NK cell activity and Th cells secretion.

PubMed

He, Li-Xia; Ren, Jin-Wei; Liu, Rui; Chen, Qi-He; Zhao, Jian; Wu, Xin; Zhang, Zhao-Feng; Wang, Jun-Bo; Pettinato, Giuseppe; Li, Yong

2017-10-01

Traditionally used as a restorative medicine, ginseng (Panax ginseng Meyer) has been the most widely used and acclaimed herb in Chinese communities for thousands of years. To investigate the immune-modulating activity of ginseng oligopeptides (GOP), 420 healthy female BALB/c mice were intragastrically administered distilled water (control), whey protein (0.15 g per kg body weight (BW)), and GOP 0.0375, 0.075, 0.15, 0.3 and 0.6 g per kg BW for 30 days. Blood samples from mice were collected from the ophthalmic venous plexus and then sacrificed by cervical dislocation. Seven assays were conducted to determine the immunomodulatory effects of GOP on innate and adaptive immune responses, followed by flow cytometry to investigate spleen T lymphocyte sub-populations, multiplex sandwich immunoassays to investigate serum cytokine and immunoglobulin levels, and ELISA to investigate intestinally secreted immunoglobulin to study the mechanism of GOP affecting the immune system. Our results showed that GOP was able to enhance innate and adaptive immune responses in mice by improving cell-mediated and humoral immunity, macrophage phagocytosis capacity and NK cell activity. Notably, the use of GOP revealed a better immune-modulating activity compared to whey protein. We conclude that the immune-modulating activity might be due to the increased macrophage phagocytosis capacity and NK cell activity, and the enhancement of T and Th cells, as well as IL-2, IL-6 and IL-12 secretion and IgA, IgG1 and IgG2b production. These results indicate that GOP could be considered a good candidate that may improve immune functions if used as a dietary supplement, with a dosage that ranges from 0.3 to 0.6 g per kg BW.

Aged Garlic Extract Modifies Human Immunity.

PubMed

Percival, Susan S

2016-02-01

Garlic contains numerous compounds that have the potential to influence immunity. Immune cells, especially innate immune cells, are responsible for the inflammation necessary to kill pathogens. Two innate lymphocytes, γδ-T and natural killer (NK) cells, appear to be susceptible to diet modification. The purpose of this review was to summarize the influence of aged garlic extract (AGE) on the immune system. The author's laboratory is interested in AGE's effects on cell proliferation and activation and inflammation and to learn whether those changes might affect the occurrence and severity of colds and flu. Healthy human participants (n = 120), between 21 and 50 y of age, were recruited for a randomized, double-blind, placebo-controlled parallel-intervention study to consume 2.56 g AGE/d or placebo supplements for 90 d during the cold and flu season. Peripheral blood mononuclear cells were isolated before and after consumption, and γδ-T and NK cell function was assessed by flow cytometry. The effect on cold and flu symptoms was determined by using daily diary records of self-reported illnesses. After 45 d of AGE consumption, γδ-T and NK cells proliferated better and were more activated than cells from the placebo group. After 90 d, although the number of illnesses was not significantly different, the AGE group showed reduced cold and flu severity, with a reduction in the number of symptoms, the number of days participants functioned suboptimally, and the number of work/school days missed. These results suggest that AGE supplementation may enhance immune cell function and may be partly responsible for the reduced severity of colds and flu reported. The results also suggest that the immune system functions well with AGE supplementation, perhaps with less accompanying inflammation. This trial was registered at clinicaltrials.gov as NCT01390116. © 2016 American Society for Nutrition.

Tumor immune evasion arises through loss of TNF sensitivity.

PubMed

Kearney, Conor J; Vervoort, Stephin J; Hogg, Simon J; Ramsbottom, Kelly M; Freeman, Andrew J; Lalaoui, Najoua; Pijpers, Lizzy; Michie, Jessica; Brown, Kristin K; Knight, Deborah A; Sutton, Vivien; Beavis, Paul A; Voskoboinik, Ilia; Darcy, Phil K; Silke, John; Trapani, Joseph A; Johnstone, Ricky W; Oliaro, Jane

2018-05-18

Immunotherapy has revolutionized outcomes for cancer patients, but the mechanisms of resistance remain poorly defined. We used a series of whole-genome clustered regularly interspaced short palindromic repeat (CRISPR)-based screens performed in vitro and in vivo to identify mechanisms of tumor immune evasion from cytotoxic lymphocytes [CD8 + T cells and natural killer (NK) cells]. Deletion of key genes within the tumor necrosis factor (TNF) signaling, interferon-γ (IFN-γ) signaling, and antigen presentation pathways provided protection of tumor cells from CD8 + T cell-mediated killing and blunted antitumor immune responses in vivo. Deletion of a number of genes in the TNF pathway also emerged as the key mechanism of immune evasion from primary NK cells. Our screens also identified that the metabolic protein 2-aminoethanethiol dioxygenase (Ado) modulates sensitivity to TNF-mediated killing by cytotoxic lymphocytes and is required for optimal control of tumors in vivo. Remarkably, we found that tumors delete the same genes when exposed to perforin-deficient CD8 + T cells, demonstrating that the dominant immune evasion strategy used by tumor cells is acquired resistance to T cell-derived cytokine-mediated antitumor effects. We demonstrate that TNF-mediated bystander killing is a potent T cell effector mechanism capable of killing antigen-negative tumor cells. In addition to highlighting the importance of TNF in CD8 + T cell- and NK cell-mediated killing of tumor cells, our study also provides a comprehensive picture of the roles of the TNF, IFN, and antigen presentation pathways in immune-mediated tumor surveillance. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

Pegylated Interferon α-2a Triggers NK-Cell Functionality and Specific T-Cell Responses in Patients with Chronic HBV Infection without HBsAg Seroconversion

PubMed Central

Bruder Costa, Juliana; Dufeu-Duchesne, Tania; Leroy, Vincent; Bertucci, Inga; Bouvier-Alias, Magali; Pouget, Noelle; Brevot-Lutton, Ophelie; Bourliere, Marc; Zoulim, Fabien

2016-01-01

Pegylated interferon α-2a (Peg-IFN-α) represents a therapeutic alternative to the prolonged use of nucleos(t)ide analog (NA) in chronic hepatitis B (CHB) infection. The mechanisms leading to a positive clinical outcome remain unclear. As immune responses are critical for virus control, we investigated the effects of Peg-IFN-α on both innate and adaptive immunity, and related it to the clinical evolution. The phenotypic and functional features of the dendritic cells (DCs), natural killer (NK) cells and HBV-specific CD4/CD8 T cells were analyzed in HBeAg-negative CHB patients treated for 48-weeks with NA alone or together with Peg-IFN-α, before, during and up to 2-years after therapy. Peg-IFN-α induced an early activation of DCs, a potent expansion of the CD56bright NK subset, and enhanced the activation and functionality of the CD56dim NK subset. Peg-IFN-α triggered an increase in the frequencies of Th1- and Th17-oriented HBV-specific CD4/CD8 T cells. Peg-IFN-α reversed the unresponsiveness of patients to a specific stimulation. Most of the parameters returned to baseline after the stop of Peg-IFN-α therapy. Peg-IFN-α impacts both innate and adaptive immunity, overcoming dysfunctional immune responses in CHB patients. These modulations were not associated with seroconversion, which questioned the benefit of the add-on Peg-IFN-α treatment. PMID:27348813

An occupational health study of emergency physicians in Japan: health assessment by immune variables (CD4, CD8, CD56, and NK cell activity) at the beginning of work.

PubMed

Okamoto, Hiroteru; Tsunoda, Tooru; Teruya, Koji; Takeda, Nobuo; Uemura, Takamoto; Matsui, Tomoko; Fukazawa, Shinji; Ichikawa, Kaoru; Takemae, Rieko; Tsuchida, Kosuke; Takashima, Yutaka

2008-01-01

This study was conducted to evaluate the occupational health of Japanese physicians in emergency medicine. Subjects participating in this study were eighty-nine physicians working at 12 medical facilities (10 critical care emergency centers) in Japan. Participants were asked to complete a questionnaire of work conditions and to provide blood samples for immune variable measurements (CD4, CD8, CD56 and natural killer cell (NK cell) activity) before commencing their work. The data collected from seventy-four of 89 participating physicians were analyzed. The traditional work group comprised of 39 emergency physicians, who were significantly overworked compared to other two groups: the shift work group and the day work group. Among these three groups, no immune variable was significantly different except lymphocyte, number of CD4, and NK cell activity; and the NK cell activity of the shift work group was significantly lower than those of the traditional work group (p<0.01) and the day work group (p<0.01) in terms of Bonferroni's multiple comparison, probably due to circadian rhythm. It was indicated that NK cell activity was significantly lower in samples collected at night versus in the morning (OR=8.34, 95%CI: 1.95-35.6, p<0.01) through multiple logistic regression analyses. NK cell activity was significantly lower in individuals taking 0-3 days off per month, as compared to those taking 4 or more days off (OR=4.65, 95%CI: 1.27-17.0, p=0.02), according to multiple logistic regression analyses. Therefore, the low NK cell activity appears to have reflected the extent of fatigue arising from physicians' overwork. Overwork would have been a potential risk for the physicians' health, resulting in a lower quality of Japanese emergency medical services than that which could have been achieved otherwise. This study suggests that it would be better for the Japanese emergency physicians to take 4 or more days off per month for their health and the quality of their services.

Tributyltin (TBT) and Dibutyltin (DBT) Alter Secretion of Tumor Necrosis Factor Alpha (TNFα) from Human Natural Killer (NK) Cells and a Mixture of T cells and NK Cells

PubMed Central

Hurt, Kelsi; Hurd-Brown, Tasia; Whalen, Margaret

2012-01-01

Butyltins (BTs) have been in widespread use. Tributyltin (TBT) has been used as a biocide in a variety of applications and is found in human blood samples. Dibutyltin (DBT) has been used as a stabilizer in polyvinyl chloride plastics and as a de-worming agent in poultry. DBT, like TBT, is found in human blood. Human natural killer (NK) cells are the earliest defense against tumors and viral infections and secrete the cytokine tumor necrosis factor (TNF) alpha (α). TNFα is an important regulator of adaptive and innate immune responses. TNFα promotes inflammation and an association between malignant transformation and inflammation has been established. Previously, we have shown that TBT and DBT were able to interfere with the ability of NK cells to lyse tumor target cells. Here we show that BTs alter cytokine secretion by NK cells as well as a mixture of T and NK lymphocytes (T/NK cells). We examined 24 h, 48 h, and 6 day exposures to TBT (200- 2.5 nM) and DBT (5- 0.05 µM) on TNFα secretion by highly enriched human NK cells and T/NK cells. The results indicate that TBT (200 - 2.5 nM) decreased TNFα secretion from NK cells. In the T/NK cells 200 nM TBT decreased secretion while 100-5 nM TBT increased secretion of TNFα. NK cells or T/NK cells exposed to higher concentrations of DBT showed decreased TNFα secretion while lower concentrations showed increased secretion. The effects of BTs on TNFα secretion are seen at concentrations present in human blood. PMID:23047847

Genetic Manipulation of NK Cells for Cancer Immunotherapy: Techniques and Clinical Implications.

PubMed

Carlsten, Mattias; Childs, Richard W

2015-01-01

Given their rapid and efficient capacity to recognize and kill tumor cells, natural killer (NK) cells represent a unique immune cell to genetically reprogram in an effort to improve the outcome of cell-based cancer immunotherapy. However, technical and biological challenges associated with gene delivery into NK cells have significantly tempered this approach. Recent advances in viral transduction and electroporation have now allowed detailed characterization of genetically modified NK cells and provided a better understanding for how these cells can be utilized in the clinic to optimize their capacity to induce tumor regression in vivo. Improving NK cell persistence in vivo via autocrine IL-2 and IL-15 stimulation, enhancing tumor targeting by silencing inhibitory NK cell receptors such as NKG2A, and redirecting tumor killing via chimeric antigen receptors, all represent approaches that hold promise in preclinical studies. This review focuses on available methods for genetic reprograming of NK cells and the advantages and challenges associated with each method. It also gives an overview of strategies for genetic reprograming of NK cells that have been evaluated to date and an outlook on how these strategies may be best utilized in clinical protocols. With the recent advances in our understanding of the complex biological networks that regulate the ability of NK cells to target and kill tumors in vivo, we foresee genetic engineering as an obligatory pathway required to exploit the full potential of NK-cell based immunotherapy in the clinic.

CAR-Engineered NK Cells Targeting Wild-Type EGFR and EGFRvIII Enhance Killing of Glioblastoma and Patient-Derived Glioblastoma Stem Cells.

PubMed

Han, Jianfeng; Chu, Jianhong; Keung Chan, Wing; Zhang, Jianying; Wang, Youwei; Cohen, Justus B; Victor, Aaron; Meisen, Walter H; Kim, Sung-hak; Grandi, Paola; Wang, Qi-En; He, Xiaoming; Nakano, Ichiro; Chiocca, E Antonio; Glorioso, Joseph C; Kaur, Balveen; Caligiuri, Michael A; Yu, Jianhua

2015-07-09

Glioblastoma (GB) remains the most aggressive primary brain malignancy. Adoptive transfer of chimeric antigen receptor (CAR)-modified immune cells has emerged as a promising anti-cancer approach, yet the potential utility of CAR-engineered natural killer (NK) cells to treat GB has not been explored. Tumors from approximately 50% of GB patients express wild-type EGFR (wtEGFR) and in fewer cases express both wtEGFR and the mutant form EGFRvIII; however, previously reported CAR T cell studies only focus on targeting EGFRvIII. Here we explore whether both wtEGFR and EGFRvIII can be effectively targeted by CAR-redirected NK cells to treat GB. We transduced human NK cell lines NK-92 and NKL, and primary NK cells with a lentiviral construct harboring a second generation CAR targeting both wtEGFR and EGFRvIII and evaluated the anti-GB efficacy of EGFR-CAR-modified NK cells. EGFR-CAR-engineered NK cells displayed enhanced cytolytic capability and IFN-γ production when co-cultured with GB cells or patient-derived GB stem cells in an EGFR-dependent manner. In two orthotopic GB xenograft mouse models, intracranial administration of NK-92-EGFR-CAR cells resulted in efficient suppression of tumor growth and significantly prolonged the tumor-bearing mice survival. These findings support intracranial administration of NK-92-EGFR-CAR cells represents a promising clinical strategy to treat GB.

Dysfunctional Natural Killer Cells in the Aftermath of Cancer Surgery.

PubMed

Angka, Leonard; Khan, Sarwat T; Kilgour, Marisa K; Xu, Rebecca; Kennedy, Michael A; Auer, Rebecca C

2017-08-17

The physiological changes that occur immediately following cancer surgeries initiate a chain of events that ultimately result in a short pro-, followed by a prolonged anti-, inflammatory period. Natural Killer (NK) cells are severely affected during this period in the recovering cancer patient. NK cells play a crucial role in anti-tumour immunity because of their innate ability to differentiate between malignant versus normal cells. Therefore, an opportunity arises in the aftermath of cancer surgery for residual cancer cells, including distant metastases, to gain a foothold in the absence of NK cell surveillance. Here, we describe the post-operative environment and how the release of sympathetic stress-related factors (e.g., cortisol, prostaglandins, catecholamines), anti-inflammatory cytokines (e.g., IL-6, TGF-β), and myeloid derived suppressor cells, mediate NK cell dysfunction. A snapshot of current and recently completed clinical trials specifically addressing NK cell dysfunction post-surgery is also discussed. In collecting and summarizing results from these different aspects of the surgical stress response, a comprehensive view of the NK cell suppressive effects of surgery is presented. Peri-operative therapies to mitigate NK cell suppression in the post-operative period could improve curative outcomes following cancer surgery.

Reduced frequency of CD56 dim CD16 pos natural killer cells in pediatric systemic inflammatory response syndrome/sepsis patients.

PubMed

Halstead, E Scott; Carcillo, Joseph A; Schilling, Bastian; Greiner, Robert J; Whiteside, Theresa L

2013-10-01

Sepsis continues to be a leading cause of death in infants and children. Natural killer (NK) cells serve as a bridge between innate and adaptive immunity, yet their role in pediatric sepsis has not been well characterized. We tested the hypothesis that decreased NK cell cytotoxicity is a common feature of pediatric systemic inflammatory response syndrome (SIRS)/sepsis patients by measuring, using flow cytometry, NK cell cytotoxicity and cell surface phenotype in the peripheral blood of 38 pediatric intensive care patients who demonstrated signs and symptoms of SIRS and/or sepsis. NK cell cytotoxicity was significantly reduced in peripheral blood mononuclear cells (PBMCs) of pediatric SIRS/sepsis patients as compared with healthy controls, and the percentage of CD56(dim) CD16(+) cytotoxic NK cells in PBMCs was lower in patients with SIRS/sepsis than in normal donors. However, on a per cell basis, CD56(dim) CD16(+) NK cells in patients mediated cytotoxicity as well as those in normal donors. The NK cell dysfunction in pediatric SIRS/sepsis patients reflects a quantitative rather than a qualitative difference from healthy controls.

Dysfunctional Natural Killer Cells in the Aftermath of Cancer Surgery

PubMed Central

Khan, Sarwat T.; Kilgour, Marisa K.; Xu, Rebecca; Kennedy, Michael A.; Auer, Rebecca C.

2017-01-01

The physiological changes that occur immediately following cancer surgeries initiate a chain of events that ultimately result in a short pro-, followed by a prolonged anti-, inflammatory period. Natural Killer (NK) cells are severely affected during this period in the recovering cancer patient. NK cells play a crucial role in anti-tumour immunity because of their innate ability to differentiate between malignant versus normal cells. Therefore, an opportunity arises in the aftermath of cancer surgery for residual cancer cells, including distant metastases, to gain a foothold in the absence of NK cell surveillance. Here, we describe the post-operative environment and how the release of sympathetic stress-related factors (e.g., cortisol, prostaglandins, catecholamines), anti-inflammatory cytokines (e.g., IL-6, TGF-β), and myeloid derived suppressor cells, mediate NK cell dysfunction. A snapshot of current and recently completed clinical trials specifically addressing NK cell dysfunction post-surgery is also discussed. In collecting and summarizing results from these different aspects of the surgical stress response, a comprehensive view of the NK cell suppressive effects of surgery is presented. Peri-operative therapies to mitigate NK cell suppression in the post-operative period could improve curative outcomes following cancer surgery. PMID:28817109

PD-1 blocks lytic granule polarization with concomitant impairment of integrin outside-in signaling in the natural killer cell immunological synapse.

PubMed

Huang, Yu; Chen, Zhiying; Jang, Joon Hee; Baig, Mirza S; Bertolet, Grant; Schroeder, Casey; Huang, Shengjian; Hu, Qian; Zhao, Yong; Lewis, Dorothy E; Qin, Lidong; Zhu, Michael Xi; Liu, Dongfang

2018-04-18

The inhibitory receptor programmed cell death protein 1 (PD-1) is upregulated on a variety of immune cells, including natural killer (NK) cells, during chronic viral infection and tumorigenesis. Blockade of PD-1 or its ligands produces durable clinical responses with tolerable side effects in patients with a broad spectrum of cancers. However, the underlying molecular mechanisms of how PD-1 regulates NK cell function remain poorly characterized. We sought to determine the effect of PD-1 signaling on NK cells. PD-1 was overexpressed in CD16-KHYG-1 (a human NK cell line with both antibody-dependent cellular cytotoxicity through CD16 and natural cytotoxicity through NKG2D) cells and stimulated by exposing the cells to NK-sensitive target cells expressing programmed death ligand 1 (PD-L1). PD-1 engagement by PD-L1 specifically blocked NK cell-mediated cytotoxicity without interfering with the conjugation between NK cells and target cells. Further examination showed that PD-1 signaling blocked lytic granule polarization in NK cells, which was accompanied by failure of integrin-linked kinase, a key molecule in the integrin outside-in signaling pathway, to accumulate in the immunological synapse after NK-target cell conjugation. Our results suggest that NK cell cytotoxicity is inhibited by PD-1 engagement, which blocks lytic granule polarization to the NK cell immunological synapse with concomitant impairment of integrin outside-in signaling. This study provides novel mechanistic insights into how PD-1 inhibition disrupts NK cell function. Copyright © 2018 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Activated human primary NK cells efficiently kill colorectal cancer cells in 3D spheroid cultures irrespectively of the level of PD-L1 expression.

PubMed

Lanuza, Pilar M; Vigueras, Alan; Olivan, Sara; Prats, Anne C; Costas, Santiago; Llamazares, Guillermo; Sanchez-Martinez, Diego; Ayuso, José María; Fernandez, Luis; Ochoa, Ignacio; Pardo, Julián

2018-01-01

Haploidentical Natural Killer (NK) cells have been shown as an effective and safe alternative for the treatment of haematological malignancies with poor prognosis for which traditional therapies are ineffective. In contrast to haematological cancer cells, that mainly grow as single suspension cells, solid carcinomas are characterised by a tridimensional (3D) architecture that provide specific surviving advantages and resistance against chemo- and radiotherapy. However, little is known about the impact of 3D growth on solid cancer immunotherapy especially adoptive NK cell transfer. We have recently developed a protocol to activate ex vivo human primary NK cells using B lymphoblastic cell lines, which generates NK cells able to overcome chemoresistance in haematological cancer cells. Here we have analysed the activity of these allogeneic NK cells against colorectal (CRC) human cell lines growing in 3D spheroid culture and correlated with the expression of some of the main ligands regulating NK cell activity. Our results indicate that activated NK cells efficiently kill colorectal tumour cell spheroids in both 2D and 3D cultures. Notably, although 3D CRC cell cultures favoured the expression of the inhibitory immune checkpoint PD-L1, it did not correlate with increased resistance to NK cells. Finally, we have analysed in detail the infiltration of NK cells in 3D spheroids by microscopy and found that at low NK cell density, cell death is not observed although NK cells are able to infiltrate into the spheroid. In contrast, higher densities promote tumoural cell death before infiltration can be detected. These findings show that highly dense activated human primary NK cells efficiently kill colorectal carcinoma cells growing in 3D cultures independently of PD-L1 expression and suggest that the use of allogeneic activated NK cells could be beneficial for the treatment of colorectal carcinoma.

Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α -Galactosylceramide-Stimulated Natural Killer T Cells.

PubMed

Lee, Sung Won; Park, Hyun Jung; Kim, Nayoung; Hong, Seokmann

2013-01-01

Natural killer dendritic cells (NKDCs) possess potent anti-tumor activity, but the cellular effect of NKDC interactions with other innate immune cells is unclear. In this study, we demonstrate that the interaction of NKDCs and natural killer T (NKT) cells is required for the anti-tumor immune responses that are elicited by α -galactosylceramide ( α -GC) in mice. The rapid and strong expression of interferon- γ by NKDCs after α -GC stimulation was dependent on NKT cells. Various NK and DC molecular markers and cytotoxic molecules were up-regulated following α -GC administration. This up-regulation could improve NKDC presentation of tumor antigens and increase cytotoxicity against tumor cells. NKDCs were required for the stimulation of DCs, NK cells, and NKT cells. The strong anti-tumor immune responses elicited by α -GC may be due to the down-regulation of regulatory T cells. Furthermore, the depletion of NKDCs dampened the tumor clearance mediated by α -GC-stimulated NKT cells in vivo. Taken together, these results indicate that complex interactions of innate immune cells might be required to achieve optimal anti-tumor immune responses during the early stages of tumorigenesis.

Immune Regulatory Properties of CD117pos Amniotic Fluid Stem Cells Vary According to Gestational Age

PubMed Central

Di Trapani, Mariano; Bassi, Giulio; Fontana, Emanuela; Giacomello, Luca; Pozzobon, Michela; Guillot, Pascale V.; De Coppi, Paolo

2015-01-01

Amniotic Fluid Stem (AFS) cells are broadly multipotent fetal stem cells derived from the positive selection and ex vivo expansion of amniotic fluid CD117/c-kitpos cells. Considering the differentiation potential in vitro toward cell lineages belonging to the three germ layers, AFS cells have raised great interest as a new therapeutic tool, but their immune properties still need to be assessed. We analyzed the in vitro immunological properties of AFS cells from different gestational age in coculture with T, B, and natural killer (NK) cells. Nonactivated (resting) first trimester-AFS cells showed lower expression of HLA class-I molecules and NK-activating ligands than second and third trimester-AFS cells, whose features were associated with lower sensitivity to NK cell-mediated lysis. Nevertheless, inflammatory priming with interferon gamma (IFN-γ) and tumor necrosis factor alpha (TNF-α) enhanced resistance of all AFS cell types to NK cytotoxicity. AFS cells modulated lymphocyte proliferation in a different manner according to gestational age: first trimester-AFS cells significantly inhibited T and NK cell proliferation, while second and third trimester-AFS cells were less efficient. In addition, only inflammatory-primed second trimester-AFS cells could suppress B cell proliferation, which was not affected by the first and third trimester-AFS cells. Indolamine 2,3 dioxygenase pathway was significantly involved only in T cell suppression mediated by second and third trimester-AFS cells. Overall, this study shows a number of significant quantitative differences among AFS cells of different gestational age that have to be considered in view of their clinical application. PMID:25072397

A combinational therapy of EGFR-CAR NK cells and oncolytic herpes simplex virus 1 for breast cancer brain metastases.

PubMed

Chen, Xilin; Han, Jianfeng; Chu, Jianhong; Zhang, Lingling; Zhang, Jianying; Chen, Charlie; Chen, Luxi; Wang, Youwei; Wang, Hongwei; Yi, Long; Elder, J Bradley; Wang, Qi-En; He, Xiaoming; Kaur, Balveen; Chiocca, E Antonio; Yu, Jianhua

2016-05-10

Breast cancer brain metastases (BCBMs) are common in patients with metastatic breast cancer and indicate a poor prognosis. These tumors are especially resistant to currently available treatments due to multiple factors. However, the combination of chimeric antigen receptor (CAR)-modified immune cells and oncolytic herpes simplex virus (oHSV) has not yet been explored in this context. In this study, NK-92 cells and primary NK cells were engineered to express the second generation of EGFR-CAR. The efficacies of anti-BCBMs of EGFR-CAR NK cells, oHSV-1, and their combination were tested in vitro and in a breast cancer intracranial mouse model. In vitro, compared with mock-transduced NK-92 cells or primary NK cells, EGFR-CAR-engineered NK-92 cells and primary NK cells displayed enhanced cytotoxicity and IFN-γ production when co-cultured with breast cancer cell lines MDA-MB-231, MDA-MB-468, and MCF-7. oHSV-1 alone was also capable of lysing and destroying these cells. However, a higher cytolytic effect of EGFR-CAR NK-92 cells was observed when combined with oHSV-1 compared to the monotherapies. In the mice intracranially pre-inoculated with EGFR-expressing MDA-MB-231 cells, intratumoral administration of either EGFR-CAR-transduced NK-92 cells or oHSV-1 mitigated tumor growth. Notably, the combination of EGFR-CAR NK-92 cells with oHSV-1 resulted in more efficient killing of MDA-MB-231 tumor cells and significantly longer survival of tumor-bearing mice when compared to monotherapies. These results demonstrate that regional administration of EGFR-CAR NK-92 cells combined with oHSV-1 therapy is a potentially promising strategy to treat BCBMs.

Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1) virus infection during pregnancy

PubMed Central

Dembinski, Jennifer L.; Laake, Ida; Hungnes, Olav; Cox, Rebecca; Oftung, Fredrik; Trogstad, Lill; Mjaaland, Siri

2017-01-01

Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI) responses in pandemic influenza A(H1N1)pdm09 (pdm09) virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu). The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC). Infected cases (N = 75) were defined by having a serum hemagglutination inhibition (HI) titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75) were randomly selected among non-infected pregnant women (HI titer <10). In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7-) and naive (CD45RA+CCR7+) CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI) symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+) CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design. PMID:29145441

Distinct T and NK cell populations may serve as immune correlates of protection against symptomatic pandemic influenza A(H1N1) virus infection during pregnancy.

PubMed

Savic, Miloje; Dembinski, Jennifer L; Laake, Ida; Hungnes, Olav; Cox, Rebecca; Oftung, Fredrik; Trogstad, Lill; Mjaaland, Siri

2017-01-01

Maternal influenza infection during pregnancy is associated with increased risk of morbidity and mortality. However, the link between the anti-influenza immune responses and health-related risks during infection is not well understood. We have analyzed memory T and NK cell mediated immunity (CMI) responses in pandemic influenza A(H1N1)pdm09 (pdm09) virus infected non-vaccinated pregnant women participating in the Norwegian Influenza Pregnancy Cohort (NorFlu). The cohort includes information on immunization, self-reported health and disease status, and biological samples (plasma and PBMC). Infected cases (N = 75) were defined by having a serum hemagglutination inhibition (HI) titer > = 20 to influenza pdm09 virus at the time of delivery, while controls (N = 75) were randomly selected among non-infected pregnant women (HI titer <10). In ELISpot assays cases had higher frequencies of IFNγ+ CD8+ T cells responding to pdm09 virus or conserved CD8 T cell-restricted influenza A virus epitopes, compared to controls. Within this T cell population, frequencies of CD95+ late effector (CD45RA+CCR7-) and naive (CD45RA+CCR7+) CD8+ memory T cells correlated inversely with self-reported influenza illness (ILI) symptoms. ILI symptoms in infected women were also associated with lower numbers of poly-functional (IFNγ+TNFα+, IL2+IFNγ+, IL2+IFNγ+TNFα+) CD4+ T cells and increased frequencies of IFNγ+CD3-CD7+ NK cells compared to asymptomatic cases, or controls, after stimulation with the pdm09 virus. Taken together, virus specific and functionally distinct T and NK cell populations may serve as cellular immune correlates of clinical outcomes of pandemic influenza disease in pregnant women. Our results may provide information important for future universal influenza vaccine design.

Epithelial-to-mesenchymal transition (EMT) induced by inflammatory priming elicits mesenchymal stromal cell-like immune-modulatory properties in cancer cells.

PubMed

Ricciardi, M; Zanotto, M; Malpeli, G; Bassi, G; Perbellini, O; Chilosi, M; Bifari, F; Krampera, M

2015-03-17

Epithelial-to-mesenchymal transition (EMT) has a central role in cancer progression and metastatic dissemination and may be induced by local inflammation. We asked whether the inflammation-induced acquisition of mesenchymal phenotype by neoplastic epithelial cells is associated with the onset of mesenchymal stromal cell-like immune-regulatory properties that may enhance tumour immune escape. Cell lines of lung adenocarcinoma (A549), breast cancer (MCF7) and hepatocellular carcinoma (HepG2) were co-cultured with T, B and NK cells before and after EMT induction by either the supernatant of mixed-lymphocyte reactions or inflammatory cytokines. EMT occurrence following inflammatory priming elicited multiple immune-regulatory effects in cancer cells resulting in NK and T-cell apoptosis, inhibition of lymphocyte proliferation and stimulation of regulatory T and B cells. Indoleamine 2,3-dioxygenase, but not Fas ligand pathway, was involved at least in part in these effects, as shown by the use of specific inhibitors. EMT induced by inflammatory stimuli confers to cancer cells some mesenchymal stromal cell-like immune-modulatory properties, which could be a cue for cancer progression and metastatic dissemination by favouring immune escape.

The natural killer cell response and tumor debulking are associated with prolonged survival in recurrent glioblastoma patients receiving dendritic cells loaded with autologous tumor lysates

PubMed Central

Pellegatta, Serena; Eoli, Marica; Frigerio, Simona; Antozzi, Carlo; Bruzzone, Maria Grazia; Cantini, Gabriele; Nava, Sara; Anghileri, Elena; Cuppini, Lucia; Cuccarini, Valeria; Ciusani, Emilio; Dossena, Marta; Pollo, Bianca; Mantegazza, Renato; Parati, Eugenio A.; Finocchiaro, Gaetano

2013-01-01

Recurrent glioblastomas (GBs) are highly aggressive tumors associated with a 6–8 mo survival rate. In this study, we evaluated the possible benefits of an immunotherapeutic strategy based on mature dendritic cells (DCs) loaded with autologous tumor-cell lysates in 15 patients affected by recurrent GB. The median progression-free survival (PFS) of this patient cohort was 4.4 mo, and the median overall survival (OS) was 8.0 mo. Patients with small tumors at the time of the first vaccination (< 20 cm3; n = 8) had significantly longer PFS and OS than the other patients (6.0 vs. 3.0 mo, p = 0.01; and 16.5 vs. 7.0 mo, p = 0.003, respectively). CD8+ T cells, CD56+ natural killer (NK) cells and other immune parameters, such as the levels of transforming growth factor β, vascular endothelial growth factor, interleukin-12 and interferon γ (IFNγ), were measured in the peripheral blood and serum of patients before and after immunization, which enabled us to obtain a vaccination/baseline ratio (V/B ratio). An increased V/B ratio for NK cells, but not CD8+ T cells, was significantly associated with prolonged PFS and OS. Patients exhibiting NK-cell responses were characterized by high levels of circulating IFNγ and E4BP4, an NK-cell transcription factor. Furthermore, the NK cell V/B ratio was inversely correlated with the TGFβ2 and VEGF V/B ratios. These results suggest that tumor-loaded DCs may increase the survival rate of patients with recurrent GB after effective tumor debulking, and emphasize the role of the NK-cell response in this therapeutic setting. PMID:23802079

Intrinsic hyporesponsiveness of invariant natural killer T cells precedes the onset of lupus

PubMed Central

Yang, J-Q; Kim, P J; Halder, R C; Singh, R R

2013-01-01

Patients with systemic lupus erythematosus (SLE) display reduced numbers and functions of invariant natural killer T (iNK T) cells, which are restored upon treatment with corticosteroids and rituximab. It is unclear whether the iNK T cell insufficiency is a consequence of disease or is a primary abnormality that precedes the onset of disease. To address this, we analysed iNK T cell function at different stages of disease development using the genetically lupus-susceptible NZB × NZW F1 (BWF1) model. We found that iNK T cell in-vivo cytokine responses to an iNK T cell ligand α-galactosylceramide (α-GalCer) were lower in BWF1 mice than in non-autoimmune BALB/c and major histocompatibility complex (MHC)-matched NZB × N/B10.PL F1 mice, although iNK T cell numbers in the periphery were unchanged in BWF1 mice compared to control mice. Such iNK T cell hyporesponsiveness in BWF1 mice was detected at a young age long before the animals exhibited any sign of autoimmunity. In-vivo activation of iNK T cells is known to transactivate other immune cells. Such transactivated T and B cell activation markers and/or cytokine responses were also lower in BWF1 mice than in BALB/c controls. Finally, we show that iNK T cell responses were markedly deficient in the NZB parent but not in NZW parent of BWF1 mice, suggesting that BWF1 might inherit the iNK T cell defect from NZB mice. Thus, iNK T cells are functionally insufficient in lupus-prone BWF1 mice. Such iNK T cell insufficiency precedes the onset of disease and may play a pathogenic role during early stages of disease development in SLE. PMID:23607366

Sea buckthorn (Hippophae rhamnoides L.) oil protects against chronic stress-induced inhibitory function of natural killer cells in rats.

PubMed

Diandong, Hou; Feng, Gu; Zaifu, Liang; Helland, Timothy; Weixin, Fu; Liping, Cai

2016-03-01

Chronic stress can suppress natural killer (NK) cell activity; this may also be related to the effect of stress on the neuroendocrine-immune network. Sea buckthorn (SBT) (Hippophae rhamnoides L.) is a thorny nitrogen fixing deciduous shrub, native to both Europe and Asia. It has been used as a medicinal plant in Tibetan and Mongolian traditional medicines. SBT has multifarious medical properties, including anti-fatigue as well as immunoregulatory effects. This study reports the effects of SBT oil with regard to the cytotoxicity and quantity of NK cells in the blood of a chronic-stress rat model, in addition to its mechanisms on the neuroendocrine-immune network. These results show that SBT oil, given by gavage to rats with chronic stress, could increase the following: body weight, NK cell quantities, and cytotoxicity, as well as the expression of perforin and granzyme B. The results also show that SBT oil in rats with chronic stress could suppress cortisol, ACTH, IL-1β and TNF-α levels, in addition to increasing 5-HT and IFN-γ serum levels. This leads to suggest that SBT oil, in rats with chronic stress, can increase NK cell cytotoxicity by upregulating the expression of perforin and granzyme B, thus causing associated effects of SBT oil on the neuroendocrine-immune network. © The Author(s) 2015.

Sea buckthorn (Hippophae rhamnoides L.) oil protects against chronic stress-induced inhibitory function of natural killer cells in rats

PubMed Central

Diandong, Hou; Feng, Gu; Zaifu, Liang; Helland, Timothy; Weixin, Fu; Liping, Cai

2015-01-01

Chronic stress can suppress natural killer (NK) cell activity; this may also be related to the effect of stress on the neuroendocrine–immune network. Sea buckthorn (SBT) (Hippophae rhamnoides L.) is a thorny nitrogen fixing deciduous shrub, native to both Europe and Asia. It has been used as a medicinal plant in Tibetan and Mongolian traditional medicines. SBT has multifarious medical properties, including anti-fatigue as well as immunoregulatory effects. This study reports the effects of SBT oil with regard to the cytotoxicity and quantity of NK cells in the blood of a chronic-stress rat model, in addition to its mechanisms on the neuroendocrine–immune network. These results show that SBT oil, given by gavage to rats with chronic stress, could increase the following: body weight, NK cell quantities, and cytotoxicity, as well as the expression of perforin and granzyme B. The results also show that SBT oil in rats with chronic stress could suppress cortisol, ACTH, IL-1β and TNF-α levels, in addition to increasing 5-HT and IFN-γ serum levels. This leads to suggest that SBT oil, in rats with chronic stress, can increase NK cell cytotoxicity by upregulating the expression of perforin and granzyme B, thus causing associated effects of SBT oil on the neuroendocrine–immune network. PMID:26684638

Neurokinin 1 Receptor Mediates Membrane Blebbing and Sheer Stress-Induced Microparticle Formation in HEK293 Cells

PubMed Central

Chen, Panpan; Douglas, Steven D.; Meshki, John; Tuluc, Florin

2012-01-01

Cell-derived microparticles participate in intercellular communication similar to the classical messenger systems of small and macro-molecules that bind to specialized membrane receptors. Microparticles have been implicated in the regulation of a variety of complex physiopathologic processes, such as thrombosis, the control of innate and adaptive immunity, and cancer. The neurokinin 1 receptor (NK1R) is a Gq-coupled receptor present on the membrane of a variety of tissues, including neurons in the central and peripheral nervous system, immune cells, endocrine and exocrine glands, and smooth muscle. The endogenous agonist of NK1R is the undecapeptide substance P (SP). We have previously described intracellular signaling mechanisms that regulate NK1R-mediated rapid cell shape changes in HEK293 cells and U373MG cells. In the present study, we show that the activation of NK1R in HEK293 cells, but not in U373MG cells, leads to formation of sheer-stress induced microparticles that stain positive with the membrane-selective fluorescent dye FM 2–10. SP-induced microparticle formation is independent of elevated intracellular calcium concentrations and activation of NK1R present on HEK293-derived microparticles triggers detectable calcium increase in SP-induced microparticles. The ROCK inhibitor Y27632 and the dynamin inhibitor dynasore inhibited membrane blebbing and microparticle formation in HEK293 cells, strongly suggesting that microparticle formation in this cell type is dependent on membrane blebbing. PMID:23024816

Neurokinin 1 receptor mediates membrane blebbing and sheer stress-induced microparticle formation in HEK293 cells.

PubMed

Chen, Panpan; Douglas, Steven D; Meshki, John; Tuluc, Florin

2012-01-01

Cell-derived microparticles participate in intercellular communication similar to the classical messenger systems of small and macro-molecules that bind to specialized membrane receptors. Microparticles have been implicated in the regulation of a variety of complex physiopathologic processes, such as thrombosis, the control of innate and adaptive immunity, and cancer. The neurokinin 1 receptor (NK1R) is a Gq-coupled receptor present on the membrane of a variety of tissues, including neurons in the central and peripheral nervous system, immune cells, endocrine and exocrine glands, and smooth muscle. The endogenous agonist of NK1R is the undecapeptide substance P (SP). We have previously described intracellular signaling mechanisms that regulate NK1R-mediated rapid cell shape changes in HEK293 cells and U373MG cells. In the present study, we show that the activation of NK1R in HEK293 cells, but not in U373MG cells, leads to formation of sheer-stress induced microparticles that stain positive with the membrane-selective fluorescent dye FM 2-10. SP-induced microparticle formation is independent of elevated intracellular calcium concentrations and activation of NK1R present on HEK293-derived microparticles triggers detectable calcium increase in SP-induced microparticles. The ROCK inhibitor Y27632 and the dynamin inhibitor dynasore inhibited membrane blebbing and microparticle formation in HEK293 cells, strongly suggesting that microparticle formation in this cell type is dependent on membrane blebbing.

Bone marrow-resident NK cells prime monocytes for regulatory function during infection

PubMed Central

Askenase, Michael H.; Han, Seong-Ji; Byrd, Allyson L.; da Fonseca, Denise Morais; Bouladoux, Nicolas; Wilhelm, Christoph; Konkel, Joanne E.; Hand, Timothy W.; Lacerda-Queiroz, Norinne; Su, Xin-Zhuan; Trinchieri, Giorgio; Grainger, John R.; Belkaid, Yasmine

2015-01-01

SUMMARY Tissue-infiltrating Ly6Chi monocytes play diverse roles in immunity, ranging from pathogen killing to immune regulation. How and where this diversity of function is imposed remains poorly understood. Here we show that during acute gastrointestinal infection, priming of monocytes for regulatory function preceded systemic inflammation and was initiated prior to bone marrow egress. Notably, natural killer (NK) cell-derived IFN-γ promoted a regulatory program in monocyte progenitors during development. Early bone marrow NK cell activation was controlled by systemic interleukin-12 (IL-12) produced by Batf3-dependent dendritic cells (DC) in the mucosal-associated lymphoid tissue (MALT). This work challenges the paradigm that monocyte function is dominantly imposed by local signals following tissue recruitment, and instead proposes a sequential model of differentiation in which monocytes are pre-emptively educated during development in the bone marrow to promote their tissue-specific function. PMID:26070484

CTLA-4+ Regulatory T Cells Increased in Cetuximab Treated Head and Neck Cancer Patients Suppress NK Cell Cytotoxicity and Correlate with Poor Prognosis

PubMed Central

Jie, Hyun-Bae; Schuler, Patrick J.; Lee, Steve C.; Srivastava, Raghvendra M.; Argiris, Athanassios; Ferrone, Soldano; Whiteside, Theresa L.; Ferris, Robert L.

2015-01-01

The EGFR-targeted antibody cetuximab is effective against head and neck cancer (HNC), but in only 15 – 20% of patients, and the variability and extent of cetuximab-mediated cellular immunity is not fully understood. We hypothesized that regulatory T cells (Treg) may exert a functional and clinical impact on antitumor immunity in cetuximab-treated individuals. The frequency, immunosuppressive phenotype and activation status of Treg and NK cells were analyzed in the circulation and tumor microenvironment of cetuximab-treated HNC patients enrolled in a novel neoadjuvant, single-agent cetuximab clinical trial. Notably, cetuximab treatment increased the frequency of CD4+FOXP3+ intratumoral Treg expressing CTLA-4, CD39 and TGF-β. These Treg suppressed cetuximab-mediated ADCC and their presence correlated with poor clinical outcome in two prospective clinical trial cohorts. Cetuximab expanded CTLA-4+FOXP3+ Treg in vitro, in part by inducing DC maturation, in combination with TGF-β and TCR triggering. Importantly, cetuximab-activated NK cells selectively eliminated intratumoral Treg but preserved effector T cells. In ex vivo assays, ipilimumab targeted CTLA-4+ Treg and restored cytolytic functions of NK cells mediating ADCC. Taken together, our results argue that differences in Treg-mediated suppression contribute to the clinical response to cetuximab treatment, suggesting its improvement by adding ipilimumab or other strategies of Treg ablation to promote anti-tumor immunity. PMID:25832655

Decreased expression of CD69 in chronic fatigue syndrome in relation to inflammatory markers: evidence for a severe disorder in the early activation of T lymphocytes and natural killer cells.

PubMed

Mihaylova, Ivana; DeRuyter, Marcel; Rummens, Jean-Luc; Bosmans, Eugene; Maes, Michael

2007-08-01

There is some evidence that patients with chronic fatigue syndrome (CFS) suffer from immune abnormalities, such as immune activation and decreased immune cell responsivity upon polyclonal stimili. This study was designed to evaluate lymphocyte activation in CFS by using a CD69 expression assay. CD69 acts as a costimulatory molecule for T- and natural killer (NK) cell activation. We collected whole blood from CFS patients, who met CDC criteria, and healthy volunteers. The blood samples were stimulated with mitogens during 18 h and the levels of activated T and NK cells expressing CD69 were measured on a Coulter Epics flow cytometer using a three color immunofluorescence staining protocol. The expression of the CD69 activation marker on T cells (CD3+, CD3+CD4+, and CD3+CD8+) and on NK cells (CD45+CD56+) was significantly lower in CFS patients than in healthy subjects. These differences were significant to the extent that a significant diagnostic performance was obtained, i.e. the area under the ROC curve was around 89%. No differences either in the number of leukocytes or in the number or percentage of lymphocytes, i.e. CD3, CD4, CD8 and CD19, could be found between CFS patients and the controls. Patients with CFS show defects in T- and NK cell activation. Since induction of CD69 surface expression is dependent on the activation of the protein kinase C (PKC) activation pathway, it is suggested that in CFS there is a disorder in the early activation of the immune system involving PKC.

Consumption of Dairy Yogurt Containing Lactobacillus paracasei ssp. paracasei, Bifidobacterium animalis ssp. lactis and Heat-Treated Lactobacillus plantarum Improves Immune Function Including Natural Killer Cell Activity.

PubMed

Lee, Ayoung; Lee, Young Ju; Yoo, Hye Jin; Kim, Minkyung; Chang, Yeeun; Lee, Dong Seog; Lee, Jong Ho

2017-05-31

The aim of this study was to investigate the impact of consuming dairy yogurt containing Lactobacillus paracasei ssp. paracasei ( L. paracasei ), Bifidobacterium animalis ssp. lactis ( B. lactis ) and heat-treated Lactobacillus plantarum ( L. plantarum ) on immune function. A randomized, open-label, placebo-controlled study was conducted on 200 nondiabetic subjects. Over a twelve-week period, the test group consumed dairy yogurt containing probiotics each day, whereas the placebo group consumed milk. Natural killer (NK) cell activity, interleukin (IL)-12 and immunoglobulin (Ig) G1 levels were significantly increased in the test group at twelve weeks compared to baseline. Additionally, the test group had significantly greater increases in serum NK cell activity and interferon (IFN)-γ and IgG1 than placebo group. Daily consumption of dairy yogurt containing L. paracasei , B. lactis and heat-treated L. plantarum could be an effective option to improve immune function by enhancing NK cell function and IFN-γ concentration (ClinicalTrials.gov: NCT03051425).

Consumption of Dairy Yogurt Containing Lactobacillus paracasei ssp. paracasei, Bifidobacterium animalis ssp. lactis and Heat-Treated Lactobacillus plantarum Improves Immune Function Including Natural Killer Cell Activity

PubMed Central

Lee, Ayoung; Lee, Young Ju; Yoo, Hye Jin; Kim, Minkyung; Chang, Yeeun; Lee, Dong Seog; Lee, Jong Ho

2017-01-01

The aim of this study was to investigate the impact of consuming dairy yogurt containing Lactobacillus paracasei ssp. paracasei (L. paracasei), Bifidobacterium animalis ssp. lactis (B. lactis) and heat-treated Lactobacillus plantarum (L. plantarum) on immune function. A randomized, open-label, placebo-controlled study was conducted on 200 nondiabetic subjects. Over a twelve-week period, the test group consumed dairy yogurt containing probiotics each day, whereas the placebo group consumed milk. Natural killer (NK) cell activity, interleukin (IL)-12 and immunoglobulin (Ig) G1 levels were significantly increased in the test group at twelve weeks compared to baseline. Additionally, the test group had significantly greater increases in serum NK cell activity and interferon (IFN)-γ and IgG1 than placebo group. Daily consumption of dairy yogurt containing L. paracasei, B. lactis and heat-treated L. plantarum could be an effective option to improve immune function by enhancing NK cell function and IFN-γ concentration (ClinicalTrials.gov: NCT03051425). PMID:28561762

Desirable cytolytic immune effector cell recruitment by interleukin-15 dendritic cells.

PubMed

Van Acker, Heleen H; Beretta, Ottavio; Anguille, Sébastien; De Caluwé, Lien; Papagna, Angela; Van den Bergh, Johan M; Willemen, Yannick; Goossens, Herman; Berneman, Zwi N; Van Tendeloo, Viggo F; Smits, Evelien L; Foti, Maria; Lion, Eva

2017-02-21

Success of dendritic cell (DC) therapy in treating malignancies is depending on the DC capacity to attract immune effector cells, considering their reciprocal crosstalk is partially regulated by cell-contact-dependent mechanisms. Although critical for therapeutic efficacy, immune cell recruitment is a largely overlooked aspect regarding optimization of DC vaccination. In this paper we have made a head-to-head comparison of interleukin (IL)-15-cultured DCs and conventional IL-4-cultured DCs with regard to their proficiency in the recruitment of (innate) immune effector cells. Here, we demonstrate that IL-4 DCs are suboptimal in attracting effector lymphocytes, while IL15 DCs provide a favorable chemokine milieu for recruiting CD8+ T cells, natural killer (NK) cells and gamma delta (γδ) T cells. Gene expression analysis revealed that IL-15 DCs exhibit a high expression of chemokines involved in antitumor immune effector cell attraction, while IL-4 DCs display a more immunoregulatory profile characterized by the expression of Th2 and regulatory T cell-attracting chemokines. This is confirmed by functional data indicating an enhanced recruitment of granzyme B+ effector lymphocytes by IL-15 DCs, as compared to IL-4 DCs, and subsequent superior killing of tumor cells by the migrated lymphocytes. Elevated CCL4 gene expression in IL-15 DCs and lowered CCR5 expression on both migrated γδ T cells and NK cells, led to validation of increased CCL4 secretion by IL15 DCs. Moreover, neutralization of CCR5 prior to migration resulted in an important inhibition of γδ T cell and NK cell recruitment by IL-15 DCs. These findings further underscore the strong immunotherapeutic potential of IL-15 DCs.

Expression of natural killer cell activity with CD107a on ectopic endometrium in woman with endometriosis compared with non-endometriosis

NASA Astrophysics Data System (ADS)

Lubis, H. P.; Aldiansyah, D.; Siregar, H. S.; Rivany, R.; Hariadi, T. S.

2018-03-01

Some factors have an important role in endometriosis pathogenesis; there is an immune cell that plays an important role in endometrial cells that have reflux. Woman with endometriosis experienced the cellular immune disorder. It is suspected that decrease of NK cell in the peritoneal fluid caused by its qualitative defect with CD107a expression as the best marker. The aim of this study was to compare expression of NK Cell activity with CD107a between awoman with endometriosis and non-endometriosis. A case-control study from March until July 2015 in Haji Adam Malik General Hospital. The case group was ectopic endometrial tissue block paraffin and control group was normal endometrial tissue block paraffin. This study included 23 patients in endometriosis group and control group respectively. A majority proportion of CD107a expression in endometriosis group was +1 (16 patients (69.6%)), while the control group was +3 (9 patients (39.1%)). Expression of NK cell activity with CD107a in patients with endometriosis was lower than the control group (p<0.05). It suggested that cellular immune factors may play a role in the pathogenesis of endometriosis.

Induction of anti-glioma natural killer cell response following multiple low-dose intracerebral CpG therapy.

PubMed

Alizadeh, Darya; Zhang, Leying; Brown, Christine E; Farrukh, Omar; Jensen, Michael C; Badie, Behnam

2010-07-01

Stimulation of toll-like receptor-9 by CpG oligodeoxynucleotides (CpG-ODN) has been shown to counteract the immunosuppressive microenvironment and to inhibit tumor growth in glioma models. These studies, however, have used high doses of CpG-ODN, which can induce toxicity in a clinical setting. The goal of this study was to evaluate the antitumor efficacy of multiple low-dose intratumoral CpG-ODN in a glioma model. Mice bearing 4-day-old intracranial GL261 gliomas received a single or multiple (two or four) intratumoral injections of CpG-ODN (3 microg) every 4 days. Tumor growth was measured by bioluminescent imaging, brain histology, and animal survival. Flow cytometry and cytotoxicity assays were used to assess anti-glioma immune response. Two and four intracranial injections of low-dose CpG-ODN, but not a single injection, eradicated gliomas in 70% of mice. Moreover, surviving animals exhibited durable tumor-free remission (> 3 months) and were protected from intracranial rechallenge with GL261 gliomas, showing the capacity for long-term antitumor immunity. Although most inflammatory cells seemed to increase, activated natural killer (NK) cells (i.e., NK(+)CD107a(+)) were more frequent than CD8(+)CD107a(+) in the brains of rechallenged CpG-ODN-treated animals and showed a stronger in vitro cytotoxicity against GL261 target cells. Leukocyte depletion studies confirmed that NK cells played an important role in the initial CpG-ODN antitumor response, but both CD8 and NK cells were equally important in long-term immunity against gliomas. These findings suggest that multiple low-dose intratumoral injections of CpG-ODN can eradicate intracranial gliomas possibly through mechanisms involving NK-mediated effector function.

Immunological abnormalities as potential biomarkers in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis

PubMed Central

2011-01-01

Background Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) is characterised by severe prolonged fatigue, and decreases in cognition and other physiological functions, resulting in severe loss of quality of life, difficult clinical management and high costs to the health care system. To date there is no proven pathomechanism to satisfactorily explain this disorder. Studies have identified abnormalities in immune function but these data are inconsistent. We investigated the profile of markers of immune function (including novel markers) in CFS/ME patients. Methods We included 95 CFS/ME patients and 50 healthy controls. All participants were assessed on natural killer (NK) and CD8+T cell cytotoxic activities, Th1 and Th2 cytokine profile of CD4+T cells, expression of vasoactive intestinal peptide receptor 2 (VPACR2), levels of NK phenotypes (CD56bright and CD56dim) and regulatory T cells expressing FoxP3 transcription factor. Results Compared to healthy individuals, CFS/ME patients displayed significant increases in IL-10, IFN-γ, TNF-α, CD4+CD25+ T cells, FoxP3 and VPACR2 expression. Cytotoxic activity of NK and CD8+T cells and NK phenotypes, in particular the CD56bright NK cells were significantly decreased in CFS/ME patients. Additionally granzyme A and granzyme K expression were reduced while expression levels of perforin were significantly increased in the CFS/ME population relative to the control population. These data suggest significant dysregulation of the immune system in CFS/ME patients. Conclusions Our study found immunological abnormalities which may serve as biomarkers in CFS/ME patients with potential for an application as a diagnostic tool. PMID:21619669

Different features of Vδ2 T and NK cells in fatal and non-fatal human Ebola infections

PubMed Central

Cimini, Eleonora; Viola, Domenico; Cabeza-Cabrerizo, Mar; Romanelli, Antonella; Tumino, Nicola; Sacchi, Alessandra; Bordoni, Veronica; Casetti, Rita; Turchi, Federica; Martini, Federico; Bore, Joseph A.; Koundouno, Fara Raymond; Duraffour, Sophie; Michel, Janine; Holm, Tobias; Zekeng, Elsa Gayle; Cowley, Lauren; Garcia Dorival, Isabel; Doerrbecker, Juliane; Hetzelt, Nicole; Baum, Jonathan H. J.; Portmann, Jasmine; Wölfel, Roman; Gabriel, Martin; Miranda, Osvaldo; Díaz, Graciliano; Díaz, José E.; Fleites, Yoel A.; Piñeiro, Carlos A.; Castro, Carlos M.; Koivogui, Lamine; Magassouba, N’Faly; Diallo, Boubacar; Ruibal, Paula; Oestereich, Lisa; Wozniak, David M.; Lüdtke, Anja; Becker-Ziaja, Beate; Capobianchi, Maria R.; Ippolito, Giuseppe; Carroll, Miles W.; Günther, Stephan; Di Caro, Antonino; Muñoz-Fontela, César

2017-01-01

Background Human Ebola infection is characterized by a paralysis of the immune system. A signature of αβ T cells in fatal Ebola infection has been recently proposed, while the involvement of innate immune cells in the protection/pathogenesis of Ebola infection is unknown. Aim of this study was to analyze γδ T and NK cells in patients from the Ebola outbreak of 2014–2015 occurred in West Africa, and to assess their association with the clinical outcome. Methodology/Principal findings Nineteen Ebola-infected patients were enrolled at the time of admission to the Ebola Treatment Centre in Guinea. Patients were divided in two groups on the basis of the clinical outcome. The analysis was performed by using multiparametric flow cytometry established by the European Mobile Laboratory in the field. A low frequency of Vδ2 T-cells was observed during Ebola infection, independently from the clinical outcome. Moreover, Vδ2 T-cells from Ebola patients massively expressed CD95 apoptotic marker, suggesting the involvement of apoptotic mechanisms in Vδ2 T-cell loss. Interestingly, Vδ2 T-cells from survivors expressed an effector phenotype and presented a lower expression of the CTLA-4 exhaustion marker than fatalities, suggesting a role of effector Vδ2 T-cells in the protection. Furthermore, patients with fatal Ebola infection were characterized by a lower NK cell frequency than patients with non fatal infection. In particular, both CD56bright and CD56dim NK frequency were very low both in fatal and non fatal infections, while a higher frequency of CD56neg NK cells was associated to non-fatal infections. Finally, NK activation and expression of NKp46 and CD158a were independent from clinical outcome. Conclusions/Significances Altogether, the data suggest that both effector Vδ2 T-cells and NK cells may play a role in the complex network of protective response to EBOV infection. Further studies are required to characterize the protective effector functions of Vδ2 and NK cells. PMID:28558022

CXCR3/CXCL10 Axis Regulates Neutrophil-NK Cell Cross-Talk Determining the Severity of Experimental Osteoarthritis.

PubMed

Benigni, Giorgia; Dimitrova, Petya; Antonangeli, Fabrizio; Sanseviero, Emilio; Milanova, Viktoriya; Blom, Arjen; van Lent, Peter; Morrone, Stefania; Santoni, Angela; Bernardini, Giovanni

2017-03-01

Several immune cell populations are involved in cartilage damage, bone erosion, and resorption processes during osteoarthritis. The purpose of this study was to investigate the role of NK cells in the pathogenesis of experimental osteoarthritis and whether and how neutrophils can regulate their synovial localization in the disease. Experimental osteoarthritis was elicited by intra-articular injection of collagenase in wild type and Cxcr3 -/- 8-wk old mice. To follow osteoarthritis progression, cartilage damage, synovial thickening, and osteophyte formation were measured histologically. To characterize the inflammatory cells involved in osteoarthritis, synovial fluid was collected early after disease induction, and the cellular and cytokine content were quantified by flow cytometry and ELISA, respectively. We found that NK cells and neutrophils are among the first cells that accumulate in the synovium during osteoarthritis, both exerting a pathogenic role. Moreover, we uncovered a crucial role of the CXCL10/CXCR3 axis, with CXCL10 increasing in synovial fluids after injury and Cxcr3 -/- mice being protected from disease development. Finally, in vivo depletion experiments showed that neutrophils are involved in an NK cell increase in the synovium, possibly by expressing CXCL10 in inflamed joints. Thus, neutrophils and NK cells act as important disease-promoting immune cells in experimental osteoarthritis and their functional interaction is promoted by the CXCL10/CXCR3 axis. Copyright © 2017 by The American Association of Immunologists, Inc.

Prolonged tomato juice consumption has no effect on cell-mediated immunity of well-nourished elderly men and women.

PubMed

Watzl, B; Bub, A; Blockhaus, M; Herbert, B M; Lührmann, P M; Neuhäuser-Berthold, M; Rechkemmer, G

2000-07-01

The immunomodulatory potential of carotenoids has been investigated thoroughly only for beta-carotene. Data on the immunomodulatory activity of other carotenoids such as lycopene are scarce. The objective of this study was to investigate the effects of prolonged tomato juice consumption on cell-mediated immunity of well-nourished healthy elderly persons. In an intervention study, 33 female and 20 male subjects (aged 63-86 y) consumed 330 mL/d tomato juice (47.1 mg/d lycopene) or mineral water for 8 wk. Immune status was assessed by measuring number and lytic activity of natural killer (NK) cells, secretion of cytokines [interleukin (IL)-2, IL-4, tumor necrosis factor-alpha (TNF-alpha)] by activated peripheral blood mononuclear cells (PBMC), lymphocyte proliferation, and delayed-type hypersensitivity (DTH) skin responses. Tomato juice consumption resulted in significantly increased plasma lycopene and beta-carotene concentrations over time. In both treatment groups, TNF-alpha and IL-4 secretion were increased at the end of the intervention period, whereas IL-2 secretion was decreased. Tomato juice consumption had no effect on lymphocyte proliferation, DTH or the number of NK cells. Lytic activity of NK cells was increased in both groups at the end of the intervention period. In conclusion, these results show that prolonged tomato juice consumption increased plasma lycopene concentrations without significantly affecting cell-mediated immunity in well-nourished elderly subjects.

The up side of decidual natural killer cells: new developments in immunology of pregnancy.

PubMed

Jabrane-Ferrat, Nabila; Siewiera, Johan

2014-04-01

Early phases of human pregnancy are associated with the accumulation of a unique subset of natural killer (NK) cells in the maternal decidua. Decidual NK (dNK) cells that are devoid of cytotoxicity play a pivotal role in successful pregnancy. By secreting large amounts of cytokines/chemokines and angiogenic factors, dNK cells participate in all steps of placentation including trophoblast invasion into the maternal endometrium and vascular remodelling. In this review, we summarize some of dNK cell features and discuss more recent exciting data that challenge the conventional view of these cells. Our new data demonstrate that dNK cells undergo fine tuning or even subvert their classical inhibitory machinery and turn into a real defence force in order to prevent the spread of viruses to fetal tissue. Today it is not clear how these phenotypic and functional adaptations impact cellular cross-talk at the fetal-maternal interface and tissue homeostasis. Ultimately, precise understanding of the molecular mechanisms that govern dNK cell plasticity during congenital human cytomegalovirus infection should lead to the design of more robust strategies to reverse immune escape during viral infection and cancer. © 2013 John Wiley & Sons Ltd.

Enriching the Housing Environment for Mice Enhances Their NK Cell Antitumor Immunity via Sympathetic Nerve-Dependent Regulation of NKG2D and CCR5.

PubMed

Song, Yanfang; Gan, Yu; Wang, Qing; Meng, Zihong; Li, Guohua; Shen, Yuling; Wu, Yufeng; Li, Peiying; Yao, Ming; Gu, Jianren; Tu, Hong

2017-04-01

Mice housed in an enriched environment display a tumor-resistant phenotype due to eustress stimulation. However, the mechanisms underlying enriched environment-induced protection against cancers remain largely unexplained. In this study, we observed a significant antitumor effect induced by enriched environment in murine pancreatic cancer and lung cancer models. This effect remained intact in T/B lymphocyte-deficient Rag1 -/- mice, but was nearly eliminated in natural killer (NK) cell-deficient Beige mice or in antibody-mediated NK-cell-depleted mice, suggesting a predominant role of NK cells in enriched environment-induced tumor inhibition. Exposure to enriched environment enhanced NK-cell activity against tumors and promoted tumoral infiltration of NK cells. Enriched environment increased the expression levels of CCR5 and NKG2D (KLRK1) in NK cells; blocking their function effectively blunted the enriched environment-induced enhancement of tumoral infiltration and cytotoxic activity of NK cells. Moreover, blockade of β-adrenergic signaling or chemical sympathectomy abolished the effects of enriched environment on NK cells and attenuated the antitumor effect of enriched environment. Taken together, our results provide new insight into the mechanism by which eustress exerts a beneficial effect against cancer. Cancer Res; 77(7); 1611-22. ©2017 AACR . ©2017 American Association for Cancer Research.

Uterine NK Cells Are Critical in Shaping DC Immunogenic Functions Compatible with Pregnancy Progression

PubMed Central

Freitag, Nancy; Otto, Teresa; Thijssen, Victor L. J. L.; Moschansky, Petra; von Kwiatkowski, Petra; Klapp, Burghard F.; Winterhager, Elke; Bauersachs, Stefan; Blois, Sandra M.

2012-01-01

Dendritic cell (DC) and natural killer (NK) cell interactions are important for the regulation of innate and adaptive immunity, but their relevance during early pregnancy remains elusive. Using two different strategies to manipulate the frequency of NK cells and DC during gestation, we investigated their relative impact on the decidualization process and on angiogenic responses that characterize murine implantation. Manipulation of the frequency of NK cells, DC or both lead to a defective decidual response characterized by decreased proliferation and differentiation of stromal cells. Whereas no detrimental effects were evident upon expansion of DC, NK cell ablation in such expanded DC mice severely compromised decidual development and led to early pregnancy loss. Pregnancy failure in these mice was associated with an unbalanced production of anti-angiogenic signals and most notably, with increased expression of genes related to inflammation and immunogenic activation of DC. Thus, NK cells appear to play an important role counteracting potential anomalies raised by DC expansion and overactivity in the decidua, becoming critical for normal pregnancy progression. PMID:23056436

Uterine NK cells are critical in shaping DC immunogenic functions compatible with pregnancy progression.

PubMed

Tirado-González, Irene; González, Irene Tirado; Barrientos, Gabriela; Freitag, Nancy; Otto, Teresa; Thijssen, Victor L J L; Moschansky, Petra; von Kwiatkowski, Petra; Klapp, Burghard F; Winterhager, Elke; Bauersachs, Stefan; Blois, Sandra M

2012-01-01

Dendritic cell (DC) and natural killer (NK) cell interactions are important for the regulation of innate and adaptive immunity, but their relevance during early pregnancy remains elusive. Using two different strategies to manipulate the frequency of NK cells and DC during gestation, we investigated their relative impact on the decidualization process and on angiogenic responses that characterize murine implantation. Manipulation of the frequency of NK cells, DC or both lead to a defective decidual response characterized by decreased proliferation and differentiation of stromal cells. Whereas no detrimental effects were evident upon expansion of DC, NK cell ablation in such expanded DC mice severely compromised decidual development and led to early pregnancy loss. Pregnancy failure in these mice was associated with an unbalanced production of anti-angiogenic signals and most notably, with increased expression of genes related to inflammation and immunogenic activation of DC. Thus, NK cells appear to play an important role counteracting potential anomalies raised by DC expansion and overactivity in the decidua, becoming critical for normal pregnancy progression.

Psychosocial job stress and immunity: a systematic review.

PubMed

Nakata, Akinori

2012-01-01

The purpose of this review was to provide current knowledge about the possible association between psychosocial job stress and immune parameters in blood, saliva, and urine. Using bibliographic databases (PubMed, PsychINFO, Web of Science, Medline) and the snowball method, 56 studies were found. In general, exposure to psychosocial job stress (high job demands, low job control, high job strain, job dissatisfaction, high effort-reward imbalance, overcommitment, burnout, unemployment, organizational downsizing, economic recession) had a measurable impact on immune parameters (reduced NK cell activity, NK and T cell subsets, CD4+/CD8+ ratio, and increased inflammatory markers). The evidence supports that psychosocial job stresses are related to disrupted immune responses but further research is needed to demonstrate cause-effect relationships.

Heterodimeric bispecific single chain variable fragments (scFv) killer engagers (BiKEs) enhance NK-cell activity against CD133+ colorectal cancer cells

PubMed Central

JU, Schmohl; MK, Gleason; PR, Dougherty; JS, Miller; DA, Vallera

2015-01-01

Background Natural killer (NK) cells are potent cytotoxic lymphocytes that play a critical role in tumor immunosurveillance and control. Cancer stem cells (CSC) initiate and sustain tumor cell growth, mediate drug refractory cancer relapse and express the well-known surface marker CD133. Methods DNA fragments from two fully humanized single chain fragment variable (scFv) antibody recognizing CD16 on NK-cells and CD133 on CSC were genetically spliced forming a novel drug, 16 × 133 BiKE that simultaneously recognizes these antigen to facilitate an immunologic synapse. The anti-CD133 was created using a fusion protein prepared by fusing DNA fragments encoding the two extracellular domains of CD133. Immunization of mice with the resulting fusion protein generated an unique antibody that recognized the molecular framework and was species cross-reactive. Results In vitro 51chromium release cytotoxicity assays at both high and low effector:target ratios demonstrated the ability of the heterodimeric biological drug to greatly enhance NK-cell killing of human Caco-2 colorectal carcinoma cells known to overexpress CD133. The tumor associated antigen specificity of the drug for CD133 even enhanced NK-cell cytotoxicity against the NK-resistant human Burkitt's lymphoma Daudi cell line, which has less than 5% CD133 surface expression. Flow cytometry analysis revealed increases in NK-cell degranulation and Interferon-γ production upon co-culture with Caco-2 targets in the presence of the drug. Conclusion These studies demonstrate that the innate immune system can be effectively recruited to kill CSC using bispecific antibodies targeting CD133, and that this anti-CD133 scFv may be useful in this bispecific platform or, perhaps, in the design of more complex trispecific molecules for carcinoma therapy. PMID:26566946

Unusual Suspects in the Development of Obesity-Induced Inflammation and Insulin Resistance: NK cells, iNKT cells, and ILCs.

PubMed

Bonamichi, Beatriz Dal Santo Francisco; Lee, Jongsoon

2017-08-01

The notion that obesity-induced inflammation mediates the development of insulin resistance in animal models and humans has been gaining strong support. It has also been shown that immune cells in local tissues, in particular in visceral adipose tissue, play a major role in the regulation of obesity-induced inflammation. Specifically, obesity increases the numbers and activation of proinflammatory immune cells, including M1 macrophages, neutrophils, Th1 CD4 T cells, and CD8 T cells, while simultaneously suppressing anti-inflammatory cells such as M2 macrophages, CD4 regulatory T cells, regulatory B cells, and eosinophils. Recently, however, new cell types have been shown to participate in the development of obesity-induced inflammation and insulin resistance. Some of these cell types also appear to regulate obesity. These cells are natural killer (NK) cells and innate lymphoid cells (ILCs), which are closely related, and invariant natural killer T (iNKT) cells. It should be noted that, although iNKT cells resemble NK cells in name, they are actually a completely different cell type in terms of their development and functions in immunity and metabolism. In this review, we will focus on the roles that these relatively new players in the metabolism field play in obesity-induced insulin resistance and the regulation of obesity. Copyright © 2017 Korean Diabetes Association.

Comparative analysis of the immunomodulatory capacities of human bone marrow- and adipose tissue-derived mesenchymal stromal cells from the same donor.

PubMed

Valencia, Jaris; Blanco, Belén; Yáñez, Rosa; Vázquez, Miriam; Herrero Sánchez, Carmen; Fernández-García, María; Rodríguez Serrano, Concepción; Pescador, David; Blanco, Juan F; Hernando-Rodríguez, Miriam; Sánchez-Guijo, Fermín; Lamana, María Luisa; Segovia, José Carlos; Vicente, Ángeles; Del Cañizo, Consuelo; Zapata, Agustín G

2016-10-01

The immunomodulatory properties of mesenchymal stromal cells (MSCs), together with their tissue regenerative potential, make them interesting candidates for clinical application. In the current study, we analyzed the in vitro immunomodulatory effects of MSCs derived from bone marrow (BM-MSCs) and from adipose tissue (AT-MSCs) obtained from the same donor on both innate and acquired immunity cells. BM-MSCs and AT-MSCs were expanded to fourth or fifth passage and co-cultured with T cells, monocytes or natural killer (NK) cells isolated from human peripheral blood and stimulated in vitro. The possible differing impact of MSCs obtained from distinct sources on phenotype, cell proliferation and differentiation, cytokine production and function of these immune cells was comparatively analyzed. BM-MSCs and AT-MSCs induced a similar decrease in NK-cell proliferation, cytokine secretion and expression of both activating receptors and cytotoxic molecules. However, only BM-MSCs significantly reduced NK-cell cytotoxic activity, although both MSC populations showed the same susceptibility to NK-cell-mediated lysis. AT-MSCs were more potent in inhibiting dendritic-cell (DC) differentiation than BM-MSC, but both MSC populations similarly reduced the ability of DCs to induce CD4(+) T-cell proliferation and cytokine production. BM-MSCs and AT-MSCs induced a similar decrease in T-cell proliferation and production of inflammatory cytokines after activation. AT-MSCs and BM-MSCs from the same donor had similar immunomodulatory capacity on both innate and acquired immunity cells. Thus, other variables, such as accessibility of samples or the frequency of MSCs in the tissue should be considered to select the source of MSC for cell therapy. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

Tumoral expression of IL-33 inhibits tumor growth and modifies the tumor microenvironment through CD8+ T and NK cells.

PubMed

Gao, Xin; Wang, Xuefeng; Yang, Qianting; Zhao, Xin; Wen, Wen; Li, Gang; Lu, Junfeng; Qin, Wenxin; Qi, Yuan; Xie, Fang; Jiang, Jingting; Wu, Changping; Zhang, Xueguang; Chen, Xinchun; Turnquist, Heth; Zhu, Yibei; Lu, Binfeng

2015-01-01

Cancer immunotherapy has shown great promise as a new standard cancer therapeutic modality. However, the response rates are limited for current approach that depends on enhancing spontaneous antitumor immune responses. Therefore, increasing tumor immunogenicity by expressing appropriate cytokines should further improve the current immunotherapy. IL-33 is a member of the IL-1 family of cytokines and is released by necrotic epithelial cells or activated innate immune cells and is thus considered a "danger" signal. The role of IL-33 in promoting type 2 immune responses and tissue inflammation has been well established. However, whether IL-33 drives antitumor immune responses is controversial. Our previous work established that IL-33 promoted the function of CD8(+) T cells. In this study, we showed that the expression of IL-33 in two types of cancer cells potently inhibited tumor growth and metastasis. Mechanistically, IL-33 increased numbers and IFN-γ production by CD8(+) T and NK cells in tumor tissues, thereby inducing a tumor microenvironment favoring tumor eradication. Importantly, IL-33 greatly increased tumor Ag-specific CD8(+) T cells. Furthermore, both NK and CD8(+) T cells were required for the antitumor effect of IL-33. Moreover, depletion of regulatory T cells worked synergistically with IL-33 expression for tumor elimination. Our studies established "alarmin" IL-33 as a promising new cytokine for tumor immunotherapy through promoting cancer-eradicating type 1 immune responses. Copyright © 2014 by The American Association of Immunologists, Inc.

Secretion of Interferon gamma (IFNγ) from Human Immune Cells is Altered by Exposure to Tributyltin (TBT) and Dibutyltin (DBT)

PubMed Central

Lawrence, Shanieek; Reid, Jacqueline; Whalen, Margaret

2013-01-01

Tributyltin (TBT) and dibutyltin (DBT) are widespread environmental contaminants found in food, beverages, and human blood samples. Both of these butyltins (BTs) interfere with the ability of human natural killer (NK) cells to lyse target cells and also alter secretion of the pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) from human immune cells in vitro. The capacity of BTs to interfere with secretion of other pro-inflammatory cytokines has not been examined. Interferon gamma (IFNγ) is a modulator of adaptive and innate immune responses, playing an important role in overall immune competence. This study shows that both TBT and DBT alter secretion of IFNγ from human immune cells. Peripheral blood cell preparations that were increasingly reconstituted were used to determine if exposures to either TBT or DBT affected IFNγ secretion and how the makeup of the cell preparation influenced that effect. IFNγ secretion was examined after 24 h, 48 h and 6 day exposures to TBT (200- 2.5 nM) and DBT (5- 0.05 μM) in highly enriched human NK cells, a monocyte-depleted preparation of PBMCs, and monocyte-containing PBMCs. Both BTs altered IFNγ secretion from NK cells at most of the conditions tested (either increasing or decreasing secretion). However, there was significant variability among donors as to the concentrations and time points that showed changes as well as the baseline secretion of IFNγ. The majority of donors showed an increase in IFNγ secretion in response to at least one concentration of TBT or DBT at a minimum of one length of exposure. PMID:24357260

IL-12-producing monocytes and HLA-E control HCMV-driven NKG2C+ NK cell expansion.

PubMed

Rölle, Alexander; Pollmann, Julia; Ewen, Eva-Maria; Le, Vu Thuy Khanh; Halenius, Anne; Hengel, Hartmut; Cerwenka, Adelheid

2014-12-01

Human cytomegalovirus (HCMV) infection is the most common cause of congenital viral infections and a major source of morbidity and mortality after organ transplantation. NK cells are pivotal effector cells in the innate defense against CMV. Recently, hallmarks of adaptive responses, such as memory-like features, have been recognized in NK cells. HCMV infection elicits the expansion of an NK cell subset carrying an activating receptor heterodimer, comprising CD94 and NKG2C (CD94/NKG2C), a response that resembles the clonal expansion of adaptive immune cells. Here, we determined that expansion of this NKG2C(+) subset and general NK cell recovery rely on signals derived from CD14(+) monocytes. In a coculture system, a subset of CD14(+) cells with inflammatory monocyte features produced IL-12 in response to HCMV-infected fibroblasts, and neutralization of IL-12 in this model substantially reduced CD25 upregulation and NKG2C(+) subset expansion. Finally, blockade of CD94/NKG2C on NK cells or silencing of the cognate ligand HLA-E in infected fibroblasts greatly impaired expansion of NKG2C(+) NK cells. Together, our results reveal that IL-12, CD14(+) cells, and the CD94/NKG2C/HLA-E axis are critical for the expansion of NKG2C(+) NK cells in response to HCMV infection. Moreover, strategies targeting the NKG2C(+) NK cell subset have the potential to be exploited in NK cell-based intervention strategies against viral infections and cancer.

IL-12–producing monocytes and HLA-E control HCMV-driven NKG2C+ NK cell expansion

PubMed Central

Rölle, Alexander; Pollmann, Julia; Ewen, Eva-Maria; Le, Vu Thuy Khanh; Halenius, Anne; Hengel, Hartmut; Cerwenka, Adelheid

2014-01-01

Human cytomegalovirus (HCMV) infection is the most common cause of congenital viral infections and a major source of morbidity and mortality after organ transplantation. NK cells are pivotal effector cells in the innate defense against CMV. Recently, hallmarks of adaptive responses, such as memory-like features, have been recognized in NK cells. HCMV infection elicits the expansion of an NK cell subset carrying an activating receptor heterodimer, comprising CD94 and NKG2C (CD94/NKG2C), a response that resembles the clonal expansion of adaptive immune cells. Here, we determined that expansion of this NKG2C+ subset and general NK cell recovery rely on signals derived from CD14+ monocytes. In a coculture system, a subset of CD14+ cells with inflammatory monocyte features produced IL-12 in response to HCMV-infected fibroblasts, and neutralization of IL-12 in this model substantially reduced CD25 upregulation and NKG2C+ subset expansion. Finally, blockade of CD94/NKG2C on NK cells or silencing of the cognate ligand HLA-E in infected fibroblasts greatly impaired expansion of NKG2C+ NK cells. Together, our results reveal that IL-12, CD14+ cells, and the CD94/NKG2C/HLA-E axis are critical for the expansion of NKG2C+ NK cells in response to HCMV infection. Moreover, strategies targeting the NKG2C+ NK cell subset have the potential to be exploited in NK cell–based intervention strategies against viral infections and cancer. PMID:25384219

ERAP1 regulates natural killer cell function by controlling the engagement of inhibitory receptors.

PubMed

Cifaldi, Loredana; Romania, Paolo; Falco, Michela; Lorenzi, Silvia; Meazza, Raffaella; Petrini, Stefania; Andreani, Marco; Pende, Daniela; Locatelli, Franco; Fruci, Doriana

2015-03-01

The endoplasmic reticulum aminopeptidase ERAP1 regulates innate and adaptive immune responses by trimming peptides for presentation by MHC class I (MHC-I) molecules. Herein, we demonstrate that genetic or pharmacological inhibition of ERAP1 on human tumor cell lines perturbs their ability to engage several classes of inhibitory receptors by their specific ligands, including killer cell Ig-like receptors (KIR) by classical MHC-I-peptide (pMHC-I) complexes and the lectin-like receptor CD94-NKG2A by nonclassical pMHC-I complexes, in each case leading to natural killer (NK) cell killing. The protective effect of pMHC-I complexes could be restored in ERAP1-deficient settings by the addition of known high-affinity peptides, suggesting that ERAP1 was needed to positively modify the affinity of natural ligands. Notably, ERAP1 inhibition enhanced the ability of NK cells to kill freshly established human lymphoblastoid cell lines from autologous or allogeneic sources, thereby promoting NK cytotoxic activity against target cells that would not be expected because of KIR-KIR ligand matching. Overall, our results identify ERAP1 as a modifier to leverage immune functions that may improve the efficacy of NK cell-based approaches for cancer immunotherapy. ©2015 American Association for Cancer Research.

Targeting CD147 for T to NK Lineage Reprogramming and Tumor Therapy.

PubMed

Geng, Jie-Jie; Tang, Juan; Yang, Xiang-Min; Chen, Ruo; Zhang, Yang; Zhang, Kui; Miao, Jin-Lin; Chen, Zhi-Nan; Zhu, Ping

2017-06-01

CD147 is highly expressed on the surface of numerous tumor cells to promote invasion and metastasis. Targeting these cells with CD147-specific antibodies has been validated as an effective approach for lung and liver cancer therapy. In the immune system, CD147 is recognized as a co-stimulatory receptor and impacts the outcome of thymic selection. Using T cell-specific deletion, we showed here that in thymus CD147 is indispensable for the stable αβ T cell lineage commitment: loss of CD147 biases both multipotent DN (double negative) and fully committed DP (double positive) cells into innate NK-like lineages. Mechanistically, CD147 deficiency results in impaired Wnt signaling and expression of BCL11b, a master transcription factor in determining T cell identity. In addition, functional blocking of CD147 by antibody phenocopies genetic deletion to enrich NK-like cells in the periphery. Furthermore, using a melanoma model and orthotopic liver cancer transplants, we showed that the augmentation of NK-like cells strongly associates with resistance against tumor growth upon CD147 suppression. Therefore, besides its original function in tumorigenesis, CD147 is also an effective surface target for immune modulation in tumor therapy. Copyright © 2017. Published by Elsevier B.V.

Isotype Diversification of IgG Antibodies to HIV Gag Proteins as a Therapeutic Vaccination Strategy for HIV Infection.

PubMed

French, Martyn A; Abudulai, Laila N; Fernandez, Sonia

2013-08-09

The development of vaccines to treat and prevent human immunodeficiency virus (HIV) infection has been hampered by an incomplete understanding of "protective" immune responses against HIV. Natural control of HIV-1 infection is associated with T-cell responses against HIV-1 Gag proteins, particularly CD8⁺ T-cell responses restricted by "protective" HLA-B alleles, but other immune responses also contribute to immune control. These immune responses appear to include IgG antibodies to HIV-1 Gag proteins, interferon-a-dependant natural killer (NK) cell responses and plasmacytoid dendritic cell (pDC) responses. Here, it is proposed that isotype diversification of IgG antibodies against HIV-1 Gag proteins, to include IgG2, as well as IgG3 and IgG1 antibodies, will broaden the function of the antibody response and facilitate accessory cell responses against HIV-1 by NK cells and pDCs. We suggest that this should be investigated as a vaccination strategy for HIV-1 infection.

Suppressor of Cytokine Signaling 2 Negatively Regulates NK Cell Differentiation by Inhibiting JAK2 Activity

PubMed Central

Kim, Won Sam; Kim, Mi Jeong; Kim, Dong Oh; Byun, Jae-Eun; Huy, Hangsak; Song, Hae Young; Park, Young-Jun; Kim, Tae-Don; Yoon, Suk Ran; Choi, Eun-Ji; Jung, Haiyoung; Choi, Inpyo

2017-01-01

Suppressor of cytokine signaling (SOCS) proteins are negative regulators of cytokine responses. Although recent reports have shown regulatory roles for SOCS proteins in innate and adaptive immunity, their roles in natural killer (NK) cell development are largely unknown. Here, we show that SOCS2 is involved in NK cell development. SOCS2−/− mice showed a high frequency of NK cells in the bone marrow and spleen. Knockdown of SOCS2 was associated with enhanced differentiation of NK cells in vitro, and the transplantation of hematopoietic stem cells (HSCs) into congenic mice resulted in enhanced differentiation in SOCS2−/− HSCs. We found that SOCS2 could inhibit Janus kinase 2 (JAK2) activity and JAK2-STAT5 signaling pathways via direct interaction with JAK2. Furthermore, SOCS2−/− mice showed a reduction in lung metastases and an increase in survival following melanoma challenge. Overall, our findings suggest that SOCS2 negatively regulates the development of NK cells by inhibiting JAK2 activity via direct interaction. PMID:28383049

Altered Natural Killer Cell Subsets in Seropositive Arthralgia and Early Rheumatoid Arthritis Are Associated with Autoantibody Status.

PubMed

Chalan, Paulina; Bijzet, Johan; Kroesen, Bart-Jan; Boots, Annemieke M H; Brouwer, Elisabeth

2016-06-01

The role of natural killer (NK) cells in the immunopathogenesis of rheumatoid arthritis (RA) is unclear. Therefore, numerical and functional alterations of CD56(dim) and CD56(bright) NK cells in the early stages of RA development were studied. Whole blood samples from newly diagnosed, treatment-naive, seropositive (SP) and seronegative (SN) patients with RA (SP RA, n = 45 and SN RA, n = 12), patients with SP arthralgia (n = 30), and healthy controls (HC, n = 41) were assessed for numbers and frequencies of T cells, B cells, and NK cells. SP status was defined as positive for anticyclic citrullinated peptide antibodies (anti-CCP) and/or rheumatoid factor (RF). Peripheral blood mononuclear cells were used for further analysis of NK cell phenotype and function. Total NK cell numbers were decreased in SP RA and SP arthralgia but not in SN RA. Also, NK cells from SP RA showed a decreased potency for interferon-γ (IFN-γ) production. A selective decrease of CD56(dim), but not CD56(bright), NK cells in SP RA and SP arthralgia was observed. This prompted investigation of CD16 (FcγRIIIa) triggering in NK cell apoptosis and cytokine expression. In vitro, CD16 triggering induced apoptosis of CD56(dim) but not CD56(bright) NK cells from HC. This apoptosis was augmented by adding interleukin 2 (IL-2). Also, CD16 triggering in the presence of IL-2 stimulated IFN-γ and tumor necrosis factor-α expression by CD56(dim) NK cells. The decline of CD56(dim) NK cells in SP arthralgia and SP RA and the in vitro apoptosis of CD56(dim) NK cells upon CD16 triggering suggest a functional role of immunoglobulin G-containing autoantibody (anti-CCP and/or RF)-immune complexes in this process. Moreover, CD16-triggered cytokine production by CD56(dim) NK cells may contribute to systemic inflammation as seen in SP arthralgia and SP RA.

NK Cells Restrain Spontaneous Antitumor CD8+ T Cell Priming through PD-1/PD-L1 Interactions with Dendritic Cells.

PubMed

Iraolagoitia, Ximena L Raffo; Spallanzani, Raul G; Torres, Nicolás I; Araya, Romina E; Ziblat, Andrea; Domaica, Carolina I; Sierra, Jessica M; Nuñez, Sol Y; Secchiari, Florencia; Gajewski, Thomas F; Zwirner, Norberto W; Fuertes, Mercedes B

2016-08-01

Despite the classical function of NK cells in the elimination of tumor and of virus-infected cells, evidence for a regulatory role for NK cells has been emerging in different models of autoimmunity, transplantation, and viral infections. However, this role has not been fully explored in the context of a growing tumor. In this article, we show that NK cells can limit spontaneous cross-priming of tumor Ag-specific CD8(+) T cells, leading to reduced memory responses. After challenge with MC57 cells transduced to express the model Ag SIY (MC57.SIY), NK cell-depleted mice exhibited a significantly higher frequency of SIY-specific CD8(+) T cells, with enhanced IFN-γ production and cytotoxic capability. Depletion of NK cells resulted in a CD8(+) T cell population skewed toward an effector memory T phenotype that was associated with enhanced recall responses and delayed tumor growth after a secondary tumor challenge with B16.SIY cells. Dendritic cells (DCs) from NK cell-depleted tumor-bearing mice exhibited a more mature phenotype. Interestingly, tumor-infiltrating and tumor-draining lymph node NK cells displayed an upregulated expression of the inhibitory molecule programmed death ligand 1 that, through interaction with programmed death-1 expressed on DCs, limited DC activation, explaining their reduced ability to induce tumor-specific CD8(+) T cell priming. Our results suggest that NK cells can, in certain contexts, have an inhibitory effect on antitumor immunity, a finding with implications for immunotherapy in the clinic. Copyright © 2016 by The American Association of Immunologists, Inc.

Transforming growth factor-beta controls T helper type 1 cell development through regulation of natural killer cell interferon-gamma.

PubMed

Laouar, Yasmina; Sutterwala, Fayyaz S; Gorelik, Leonid; Flavell, Richard A

2005-06-01

Interferon-gamma and interleukin 12 produced by the innate arm of the immune system are important regulators of T helper type 1 (T(H)1) cell development, but signals that negatively regulate their expression remain controversial. Here we show that transforming growth factor-beta (TGF-beta) controlled T(H)1 differentiation through the regulation of interferon-gamma produced by natural killer (NK) cells. Blockade of TGF-beta signaling in NK cells caused the accumulation of a large pool of NK cells secreting copious interferon-gamma, responsible for T(H)1 differentiation and protection from leishmania infection. In contrast, blockade of TGF-beta signaling in dendritic cells did not affect dendritic cell homeostasis or interleukin 12 production, thus indicating a previously undescribed demarcation of the function of TGF-beta in NK cells versus dendritic cells.

Immune Evasion and Recognition of the Syphilis Spirochete in Blood and Skin of Secondary Syphilis Patients: Two Immunologically Distinct Compartments

PubMed Central

Cruz, Adriana R.; Ramirez, Lady G.; Zuluaga, Ana V.; Pillay, Allan; Abreu, Christine; Valencia, Carlos A.; La Vake, Carson; Cervantes, Jorge L.; Dunham-Ems, Star; Cartun, Richard; Mavilio, Domenico; Radolf, Justin D.; Salazar, Juan C.

2012-01-01

Background The clinical syndrome associated with secondary syphilis (SS) reflects the propensity of Treponema pallidum (Tp) to escape immune recognition while simultaneously inducing inflammation. Methods To better understand the duality of immune evasion and immune recognition in human syphilis, herein we used a combination of flow cytometry, immunohistochemistry (IHC), and transcriptional profiling to study the immune response in the blood and skin of 27 HIV(-) SS patients in relation to spirochetal burdens. Ex vivo opsonophagocytosis assays using human syphilitic sera (HSS) were performed to model spirochete-monocyte/macrophage interactions in vivo. Results Despite the presence of low-level spirochetemia, as well as immunophenotypic changes suggestive of monocyte activation, we did not detect systemic cytokine production. SS subjects had substantial decreases in circulating DCs and in IFNγ-producing and cytotoxic NK-cells, along with an emergent CD56−/CD16+ NK-cell subset in blood. Skin lesions, which had visible Tp by IHC and substantial amounts of Tp-DNA, had large numbers of macrophages (CD68+), a relative increase in CD8+ T-cells over CD4+ T-cells and were enriched for CD56+ NK-cells. Skin lesions contained transcripts for cytokines (IFN-γ, TNF-α), chemokines (CCL2, CXCL10), macrophage and DC activation markers (CD40, CD86), Fc-mediated phagocytosis receptors (FcγRI, FcγR3), IFN-β and effector molecules associated with CD8 and NK-cell cytotoxic responses. While HSS promoted uptake of Tp in conjunction with monocyte activation, most spirochetes were not internalized. Conclusions Our findings support the importance of macrophage driven opsonophagocytosis and cell mediated immunity in treponemal clearance, while suggesting that the balance between phagocytic uptake and evasion is influenced by the relative burdens of bacteria in blood and skin and the presence of Tp subpopulations with differential capacities for binding opsonic antibodies. They also bring to light the extent of the systemic innate and adaptive immunologic abnormalities that define the secondary stage of the disease, which in the skin of patients trends towards a T-cell cytolytic response. PMID:22816000

Toll-like receptor-5 agonist, entolimod, suppresses metastasis and induces immunity by stimulating an NK-dendritic-CD8+ T-cell axis

PubMed Central

Brackett, Craig M.; Kojouharov, Bojidar; Veith, Jean; Greene, Kellee F.; Burdelya, Lyudmila G.; Gollnick, Sandra O.; Abrams, Scott I.; Gudkov, Andrei V.

2016-01-01

Activation of an anticancer innate immune response is highly desirable because of its inherent ability to generate an adaptive antitumor T-cell response. However, insufficient safety of innate immune modulators limits clinical use to topical applications. Toll-like receptor 5 (TLR5) agonists are favorably positioned as potential systemic immunotherapeutic agents because of unusual tissue specificity of expression, uniquely safe profile of induced cytokines, and antitumor efficacy demonstrated in a number of animal models. Here, we decipher the molecular and cellular events underlying the metastasis suppressive activity of entolimod, a clinical stage TLR5 agonist that activates NF-κB–, AP-1–, and STAT3–driven immunomodulatory signaling pathways specifically within the liver. Used as a single agent in murine colon and mammary metastatic cancer models, entolimod rapidly induces CXCL9 and -10 that support homing of blood-borne CXCR3-expressing NK cells to the liver predominantly through an IFN-γ signaling independent mechanism. NK cell-dependent activation of dendritic cells is followed by stimulation of a CD8+ T-cell response, which exert both antimetastatic effect of entolimod and establishment of tumor-specific and durable immune memory. These results define systemically administered TLR5 agonists as organ-specific immunoadjuvants, enabling efficient antitumor vaccination that does not depend on identification of tumor-specific antigens. PMID:26831100

Downregulation of Interleukin-18-Mediated Cell Signaling and Interferon Gamma Expression by the Hepatitis B Virus e Antigen

PubMed Central

Jegaskanda, S.; Ahn, S. H.; Skinner, N.; Thompson, A. J.; Ngyuen, T.; Holmes, J.; De Rose, R.; Navis, M.; Winnall, W. R.; Kramski, M.; Bernardi, G.; Bayliss, J.; Colledge, D.; Sozzi, V.; Visvanathan, K.; Locarnini, S. A.; Kent, S. J.

2014-01-01

ABSTRACT The mechanisms by which hepatitis B virus (HBV) establishes and maintains chronic hepatitis B infection (CHB) are poorly defined. Innate immune responses play an important role in reducing HBV replication and pathogenesis. HBV has developed numerous mechanisms to escape these responses, including the production of the secreted hepatitis B e antigen (HBeAg), which has been shown to regulate antiviral toll-like receptor (TLR) and interleukin-1 (IL-1) signaling. IL-18 is a related cytokine that inhibits HBV replication in hepatoma cell lines and in the liver through the induction of gamma interferon (IFN-γ) by NK cells and T cells. We hypothesized that HBV or HBV proteins inhibit IFN-γ expression by NK cells as an accessory immunomodulatory function. We show that HBeAg protein inhibits the NF-κB pathway and thereby downregulates NK cell IFN-γ expression. Additionally, IFN-γ expression was significantly inhibited by exposure to serum from individuals with HBeAg-positive but not HBeAg-negative chronic HBV infection. Further, we show that the HBeAg protein suppresses IL-18-mediated NF-κB signaling in NK and hepatoma cells via modulation of the NF-κB pathway. Together, these findings show that the HBeAg inhibits IL-18 signaling and IFN-γ expression, which may play an important role in the establishment and/or maintenance of persistent HBV infection. IMPORTANCE It is becoming increasingly apparent that NK cells play a role in the establishment and/or maintenance of chronic hepatitis B infection. The secreted HBeAg is an important regulator of innate and adaptive immune responses. We now show that the HBeAg downregulates NK cell-mediated IFN-γ production and IL-18 signaling, which may contribute to the establishment of infection and/or viral persistence. Our findings build on previous studies showing that the HBeAg also suppresses the TLR and IL-1 signaling pathways, suggesting that this viral protein is a key regulator of antiviral innate immune responses. PMID:24872585

NK T Cells Contribute to Expansion of CD8+ T Cells and Amplification of Antiviral Immune Responses to Respiratory Syncytial Virus

PubMed Central

Johnson, Teresa R.; Hong, Seokmann; Van Kaer, Luc; Koezuka, Yasuhiko; Graham, Barney S.

2002-01-01

CD1d-deficient mice have normal numbers of T lymphocytes and natural killer cells but lack Vα14+ natural killer T cells. Respiratory syncytial virus (RSV) immunopathogenesis was evaluated in 129×C57BL/6, C57BL/6, and BALB/c CD1d−/− mice. CD8+ T lymphocytes were reduced in CD1d−/− mice of all strains, as shown by cell surface staining and major histocompatibility complex class I tetramer analysis, and resulted in strain-specific alterations in illness, viral clearance, and gamma interferon (IFN-γ) production. Transient activation of NK T cells in CD1d+/+ mice by α-GalCer resulted in reduced illness and delayed viral clearance. These data suggest that early IFN-γ production and efficient induction of CD8+-T-cell responses during primary RSV infection require CD1d-dependent events. We also tested the ability of α-GalCer as an adjuvant to modulate the type 2 immune responses induced by RSV glycoprotein G or formalin-inactivated RSV immunization. However, immunized CD1-deficient or α-GalCer-treated wild-type mice did not exhibit diminished disease following RSV challenge. Rather, some disease parameters, including cytokine production, eosinophilia, and viral clearance, were increased. These findings indicate that CD1d-dependent NK T cells play a role in expansion of CD8+ T cells and amplification of antiviral responses to RSV. PMID:11932395

Tracking KLRC2 (NKG2C)+ memory-like NK cells in SIV+ and rhCMV+ rhesus macaques.

PubMed

Ram, Daniel R; Manickam, Cordelia; Hueber, Brady; Itell, Hannah L; Permar, Sallie R; Varner, Valerie; Reeves, R Keith

2018-05-01

Natural killer (NK) cells classically typify the nonspecific effector arm of the innate immune system, but have recently been shown to possess memory-like properties against multiple viral infections, most notably CMV. Expression of the activating receptor NKG2C is elevated on human NK cells in response to infection with CMV as well as HIV, and may delineate cells with memory and memory-like functions. A better understanding of how NKG2C+ NK cells specifically respond to these pathogens could be significantly advanced using nonhuman primate (NHP) models but, to date, it has not been possible to distinguish NKG2C from its inhibitory counterpart, NKG2A, in NHP because of unfaithful antibody cross-reactivity. Using novel RNA-based flow cytometry, we identify for the first time true memory NKG2C+ NK cells in NHP by gene expression (KLRC2), and show that these cells have elevated frequencies and diversify their functional repertoire specifically in response to rhCMV and SIV infections.

Overexpression of LLT1 (OCIL, CLEC2D) on prostate cancer cells inhibits NK cell-mediated killing through LLT1-NKRP1A (CD161) interaction.

PubMed

Mathew, Stephen O; Chaudhary, Pankaj; Powers, Sheila B; Vishwanatha, Jamboor K; Mathew, Porunelloor A

2016-10-18

Prostate cancer is the most common type of cancer diagnosed and the second leading cause of cancer-related death in American men. Natural Killer (NK) cells are the first line of defense against cancer and infections. NK cell function is regulated by a delicate balance between signals received through activating and inhibitory receptors. Previously, we identified Lectin-like transcript-1 (LLT1/OCIL/CLEC2D) as a counter-receptor for the NK cell inhibitory receptor NKRP1A (CD161). Interaction of LLT1 expressed on target cells with NKRP1A inhibits NK cell activation. In this study, we have found that LLT1 was overexpressed on prostate cancer cell lines (DU145, LNCaP, 22Rv1 and PC3) and in primary prostate cancer tissues both at the mRNA and protein level. We further showed that LLT1 is retained intracellularly in normal prostate cells with minimal cell surface expression. Blocking LLT1 interaction with NKRP1A by anti-LLT1 mAb on prostate cancer cells increased the NK-mediated cytotoxicity of prostate cancer cells. The results indicate that prostate cancer cells may evade immune attack by NK cells by expressing LLT1 to inhibit NK cell-mediated cytolytic activity through LLT1-NKRP1A interaction. Blocking LLT1-NKRP1A interaction will make prostate cancer cells susceptible to killing by NK cells and therefore may be a new therapeutic option for treatment of prostate cancer.

Substance P and the neurokinin-1 receptor expression in dog ileum with and without inflammation.

PubMed

Polidoro, Giulia; Giancola, Fiorella; Fracassi, Federico; Pietra, Marco; Bettini, Giuliano; Asti, Martina; Chiocchetti, Roberto

2017-10-01

In the gastrointestinal tract, the tachykinin Substance P (SP) is involved in motility, fluid and electrolyte secretion, and blood flow and regulation of immunoinflammatory response. SP exerts its biological activity on target cells by interacting mainly with the neurokinin-1 receptor (NK 1 R). The present study aims to quantify the percentage of SP-immunoreactive (SP-IR) enteric neurons and the density of SP-IR nerve fibers in the ileum of control dogs (CTRL-dogs; n=7) vs dogs with spontaneous ileal inflammation (INF-dogs; n=8). In addition, the percentage of enteric neurons bearing NK 1 R, and nitrergic neurons (nNOS-IR) expressing NK 1 R immunoreactivity were evaluated in both groups. The percentages of SP-IR neurons were similar in CTRL- and INF-dogs, in either the myenteric (MP) (15±8% vs. 16±7%, respectively) and submucosal plexus (SMP) (26±7% vs. 24±14%, respectively). In INF-dogs, the density of SP-IR mucosal nerve fibers showed a trend to decrease (P=0.07). Myenteric neurons of CTRL- and INF-dogs expressed similar percentages of NK 1 R-immunoreactivity (39±5% vs. 38±20%, respectively). Submucosal NK 1 R-IR neurons were occasionally observed in a CTRL-dog. MP nitrergic neurons bearing NK 1 R showed a trend to decrease in INF-dogs vs. CTRL- dogs (41±22% vs. 65±10%, respectively; P=0.11). In INF-dogs, muscle cells and immune cells overexpressed NK 1 R immunoreactivity. These findings should be taken as a warning for possible intestinal motility disorders, which might occur during administration of NK 1 R-antagonist drugs. Conversely, the strong expression of NK 1 R immunoreactivity observed in muscle and mucosal immune cells of inflamed tissues may provide a rationale for the use of NK 1 R antagonist drugs in the treatment of intestinal inflammation. Copyright © 2017 Elsevier Ltd. All rights reserved.

CD94/NKG2A inhibits NK cell activation by disrupting the actin network at the immunological synapse.

PubMed

Masilamani, Madhan; Nguyen, Connie; Kabat, Juraj; Borrego, Francisco; Coligan, John E

2006-09-15

An adequate immune response is the result of the fine balance between activation and inhibitory signals. The exact means by which inhibitory signals obviate activation signals in immune cells are not totally elucidated. Human CD94/NKG2A is an ITIM-containing inhibitory receptor expressed by NK cells and some CD8+ T cells that recognize HLA-E. We show that the engagement of this receptor prevents NK cell activation by disruption of the actin network and exclusion of lipid rafts at the point of contact with its ligand (inhibitory NK cell immunological synapse, iNKIS). CD94/NKG2A engagement leads to recruitment and activation of src homology 2 domain-bearing tyrosine phosphatase 1. This likely explains the observed dephosphorylation of guanine nucleotide exchange factor and regulator of actin, Vav1, as well as ezrin-radixin-moesin proteins that connect actin filaments to membrane structures. In contrast, NK cell activation by NKG2D induced Vav1 and ezrin-radixin-moesin phosphorylation. Thus, CD94/NKG2A prevents actin-dependent recruitment of raft-associated activation receptors complexes to the activating synapse. This was further substantiated by showing that inhibition of actin polymerization abolished lipid rafts exclusion at the iNKIS, whereas cholesterol depletion had no effect on actin disruption at the iNKIS. These data indicate that the lipid rafts exclusion at the iNKIS is an active process which requires an intact cytoskeleton to maintain lipid rafts outside the inhibitory synapse. The net effect is to maintain an inhibitory state in the proximity of the iNKIS, while allowing the formation of activation synapse at distal points within the same NK cell.

Anticancer drugs cause release of exosomes with heat shock proteins from human hepatocellular carcinoma cells that elicit effective natural killer cell antitumor responses in vitro.

PubMed

Lv, Li-Hong; Wan, Yun-Le; Lin, Yan; Zhang, Wei; Yang, Mei; Li, Guo-Lin; Lin, Hao-Ming; Shang, Chang-Zhen; Chen, Ya-Jin; Min, Jun

2012-05-04

Failure of immune surveillance related to inadequate host antitumor immune responses has been suggested as a possible cause of the high incidence of recurrence and poor overall survival outcome of hepatocellular carcinoma. The stress-induced heat shock proteins (HSPs) are known to act as endogenous "danger signals" that can improve tumor immunogenicity and induce natural killer (NK) cell responses. Exosome is a novel secretory pathway for HSPs. In our experiments, the immune regulatory effect of the HSP-bearing exosomes secreted by human hepatocellular carcinoma cells under stress conditions on NK cells was studied. ELISA results showed that the production of HSP60, HSP70, and HSP90 was up-regulated in both cell lines in a stress-specific manner. After exposure to hepatocellular carcinoma cell-resistant or sensitive anticancer drugs (hereafter referred to as "resistant" or "sensitive" anticancer drug), the membrane microvesicles were actively released by hepatocellular carcinoma cells, differing in their ability to present HSPs on the cell surface, which were characterized as exosomes. Acting as a decoy, the HSP-bearing exosomes efficiently stimulated NK cell cytotoxicity and granzyme B production, up-regulated the expression of inhibitory receptor CD94, and down-regulated the expression of activating receptors CD69, NKG2D, and NKp44. Notably, resistant anticancer drugs enhanced exosome release and generated more exosome-carried HSPs, which augmented the activation of the cytotoxic response. In summary, our findings demonstrated that exosomes derived from resistant anticancer drug-treated HepG2 cells conferred superior immunogenicity in inducing HSP-specific NK cell responses, which provided a clue for finding an efficient vaccine for hepatocellular carcinoma immunotherapy.

Tumor-Targeting Anti-CD20 Antibodies Mediate In Vitro Expansion of Memory Natural Killer Cells: Impact of CD16 Affinity Ligation Conditions and In Vivo Priming.

PubMed

Capuano, Cristina; Battella, Simone; Pighi, Chiara; Franchitti, Lavinia; Turriziani, Ombretta; Morrone, Stefania; Santoni, Angela; Galandrini, Ricciarda; Palmieri, Gabriella

2018-01-01

Natural killer (NK) cells represent a pivotal player of innate anti-tumor immune responses. The impact of environmental factors in shaping the representativity of different NK cell subsets is increasingly appreciated. Human cytomegalovirus (HCMV) infection profoundly affects NK cell compartment, as documented by the presence of a CD94/NKG2C + FcεRIγ - long-lived "memory" NK cell subset, endowed with enhanced CD16-dependent functional capabilities, in a fraction of HCMV-seropositive subjects. However, the requirements for memory NK cell pool establishment/maintenance and activation have not been fully characterized yet. Here, we describe the capability of anti-CD20 tumor-targeting therapeutic monoclonal antibodies (mAbs) to drive the selective in vitro expansion of memory NK cells and we show the impact of donor' HCMV serostatus and CD16 affinity ligation conditions on this event. In vitro expanded memory NK cells maintain the phenotypic and functional signature of their freshly isolated counterpart; furthermore, our data demonstrate that CD16 affinity ligation conditions differently affect memory NK cell proliferation and functional activation, as rituximab-mediated low-affinity ligation represents a superior proliferative stimulus, while high-affinity aggregation mediated by glycoengineered obinutuzumab results in improved multifunctional responses. Our work also expands the molecular and functional characterization of memory NK cells, and investigates the possible impact of CD16 functional allelic variants on their in vivo and in vitro expansions. These results reveal new insights in Ab-driven memory NK cell responses in a therapeutic setting and may ultimately inspire new NK cell-based intervention strategies against cancer, in which the enhanced responsiveness to mAb-bound target could significantly impact therapeutic efficacy.

Astrocyte-derived interleukin-15 exacerbates ischemic brain injury via propagation of cellular immunity.

PubMed

Li, Minshu; Li, Zhiguo; Yao, Yang; Jin, Wei-Na; Wood, Kristofer; Liu, Qiang; Shi, Fu-Dong; Hao, Junwei

2017-01-17

Astrocytes are believed to bridge interactions between infiltrating lymphocytes and neurons during brain ischemia, but the mechanisms for this action are poorly understood. Here we found that interleukin-15 (IL-15) is dramatically up-regulated in astrocytes of postmortem brain tissues from patients with ischemic stroke and in a mouse model of transient focal brain ischemia. We generated a glial fibrillary acidic protein (GFAP) promoter-controlled IL-15-expressing transgenic mouse (GFAP-IL-15 tg ) line and found enlarged brain infarcts, exacerbated neurodeficits after the induction of brain ischemia. In addition, knockdown of IL-15 in astrocytes attenuated ischemic brain injury. Interestingly, the accumulation of CD8 + T and natural killer (NK) cells was augmented in these GFAP-IL-15 tg mice after brain ischemia. Of note, depletion of CD8 + T or NK cells attenuated ischemic brain injury in GFAP-IL-15 tg mice. Furthermore, knockdown of the IL-15 receptor α or blockade of cell-to-cell contact diminished the activation and effector function of CD8 + T and NK cells in GFAP-IL-15 tg mice, suggesting that astrocytic IL-15 is delivered in trans to target cells. Collectively, these findings indicate that astrocytic IL-15 could aggravate postischemic brain damage via propagation of CD8 + T and NK cell-mediated immunity.

Developmental changes in intraepithelial T lymphocytes and NK cells in the small intestine of neonatal rats.

PubMed

Pérez-Cano, Francisco J; Castellote, Cristina; González-Castro, Ana M; Pelegrí, Carme; Castell, Margarida; Franch, Angels

2005-11-01

The main objective of this study was to characterize developmental changes in small intestinal intraepithelial lymphocyte (IEL) subpopulations during the suckling period, thus contributing to the understanding of the development of diffuse gut-associated lymphoid tissue (GALT) and to the identification of early mechanisms that protect the neonate from the first contact with diet and gut microbial antigens. The study was performed by double labeling and flow cytometry in IEL isolated from the proximal and distal small intestine of 1- to 21-d-old Lewis rats. During the suckling period, intraepithelial natural killer (NK) cells changed from a typical systemic phenotype, CD8+, to a specific intestinal phenotype, CD8-. Analysis of CD8+ IEL revealed a progressive increase in the relative number of CD8+ IEL co-expressing TCRalphabeta, cells associated with acquired immunity, whereas the percentage of CD8+ cells expressing the NK receptor, i.e. cells committed to innate immunity, decreased. At weaning, IEL maturity was still not achieved, as revealed by a phenotypic pattern that differed from that of adult rats. Thus, late after weaning, the regulatory CD8+CD4+ T IEL population appeared and the NK population declined. In summary, the intestinal intraepithelial compartment undergoes changes in its lymphocyte composition associated with the first ingestion of food. These changes are focused on a relatively high proportion of NK cells during the suckling period, and after weaning, an expansion of the regulatory CD8+CD4+ T cells.

Effects of selective type I and II adrenal steroid agonists on immune cell distribution.

PubMed

Miller, A H; Spencer, R L; hassett, J; Kim, C; Rhee, R; Ciurea, D; Dhabhar, F; McEwen, B; Stein, M

1994-11-01

Adrenal steroids exert their effects through two distinct adrenal steroid receptor subtypes; the high affinity type I, or mineralocorticoid, receptor and the lower affinity type II, or glucocorticoid, receptor. Adrenal steroids have well known effects on immune cell distribution, and although both type I and II receptors are expressed in immune cells and tissues, few data exist on the relative effects mediated through these two receptor subtypes. Accordingly, we administered selective type I and II adrenal steroid receptor agonists to young adult male Sprague-Dawley rats for 7 days and then measured immune cell distribution in the peripheral blood and spleen. Results were compared with those of similar studies using the naturally occurring glucocorticoid of the rat, corticosterone, which binds both type I and II receptors. The majority of the well characterized effects of adrenal steroids on peripheral blood immune cells (increased neutrophils and decreased lymphocytes and monocytes) were reproduced by the type II receptor agonist, RU28362. RU28362 decreased the numbers of all lymphocyte subsets [T-cells, B-cells, and natural killer (NK) cells] to very low absolute levels. The largest relative decrease (i.e. in percentage) was seen in B-cells, whereas NK cells exhibited the least relative decrease and actually showed a 2-fold increase in relative percentage during RU28362 treatment. Similar to RU28362, the type I receptor agonist, aldosterone, significantly reduced the number of lymphocytes and monocytes. In contrast to RU28362, however, aldosterone significantly decreased the number of neutrophils. Moreover, aldosterone decreased the number of T-helper cells and NK cells, while having no effect on the number of B-cells or T-suppressor/cytotoxic cells. Corticosterone at physiologically relevant concentrations had potent effects on immune cell distribution, which were indistinguishable from those of the type II receptor agonist, RU28362. Taken together, these results indicate that effects of adrenal steroids on immune cell distribution are dependent on the receptor subtype involved as well as the specific cell type targeted. These factors allow for varied and complex effects of adrenal steroids on the immune system under physiological conditions.

Activation of natural killer cells by hepatitis C virus particles in vitro

PubMed Central

Farag, M M S; Weigand, K; Encke, J; Momburg, F

2011-01-01

Little is known about the ability of hepatitis C virus (HCV) to alter early innate immune responses in infected patients. Previous studies have shown that natural killer (NK) cells are functionally impaired after interaction of recombinant HCV glycoprotein E2 with the co-stimulatory CD81 molecule in vitro; however, the functional consequences of a prolonged contact of NK cells with HCV particles have remained unclear. We have examined the phenotypes of purified, interleukin-2-activated NK cells from healthy donors and HCV genotype 1b patients after culture for 5 days with HCV pseudoparticles (HCVpp) and serum samples containing HCV genotype 1b. NK cells from healthy donors and chronic HCV patients were found to up-regulate receptors associated with activation (NKp46, NKp44, NKp30, NKG2D), while NK receptors from the killer cell immunoglobulin-like receptor family (KIR/CD158), predominantly having an inhibitory function, were significantly down-modulated after culture in the presence of HCV particles compared with control cultures of NK cells. HCV-infected sera and HCVpp elicited significantly higher secretion of the NK effector lymphokines interferon-γ and tumour necrosis factor-α. Furthermore, HCV stimulated the cytotoxic potential of NK cells from normal donors and patients. The enhanced activation of NK cells after prolonged culture with HCVpp or HCV-containing sera for 5 days suggests that these innate effector cells may play an important role in viral control during early phases of HCV infection. PMID:21682720

NK Cell Activation in Human Hantavirus Infection Explained by Virus-Induced IL-15/IL15Rα Expression

PubMed Central

Braun, Monika; Björkström, Niklas K.; Gupta, Shawon; Sundström, Karin; Ahlm, Clas; Klingström, Jonas; Ljunggren, Hans-Gustaf

2014-01-01

Clinical infection with hantaviruses cause two severe acute diseases, hemorrhagic fever with renal syndrome (HFRS) and hantavirus pulmonary syndrome (HPS). These diseases are characterized by strong immune activation, increased vascular permeability, and up to 50% case-fatality rates. One prominent feature observed in clinical hantavirus infection is rapid expansion of natural killer (NK) cells in peripheral blood of affected individuals. We here describe an unusually high state of activation of such expanding NK cells in the acute phase of clinical Puumala hantavirus infection. Expanding NK cells expressed markedly increased levels of activating NK cell receptors and cytotoxic effector molecules. In search for possible mechanisms behind this NK cell activation, we observed virus-induced IL-15 and IL-15Rα on infected endothelial and epithelial cells. Hantavirus-infected cells were shown to strongly activate NK cells in a cell-cell contact-dependent way, and this response was blocked with anti-IL-15 antibodies. Surprisingly, the strength of the IL-15-dependent NK cell response was such that it led to killing of uninfected endothelial cells despite expression of normal levels of HLA class I. In contrast, hantavirus-infected cells were resistant to NK cell lysis, due to a combination of virus-induced increase in HLA class I expression levels and hantavirus-mediated inhibition of apoptosis induction. In summary, we here describe a possible mechanism explaining the massive NK cell activation and proliferation observed in HFRS patients caused by Puumala hantavirus infection. The results add further insights into mechanisms behind the immunopathogenesis of hantavirus infections in humans and identify new possible targets for intervention. PMID:25412359

Immune-mediated neuropathy with Epstein-Barr virus-positive T-cell lymphoproliferative disease.

PubMed

Hattori, Takaaki; Arai, Ayako; Yokota, Takanori; Imadome, Ken-Ichi; Tomimitsu, Hiroyuki; Miura, Osamu; Mizusawa, Hidehiro

2015-01-01

A 47-year-old man with Epstein-Barr virus (EBV)-positive T/NK- cell lymphoproliferative disease (EBV-T/NK-LPD) developed acute-onset weakness. A nerve conduction study showed a conduction block in both the proximal and most distal segments. Although the patient's neuropathy transiently responded to intravenous immunoglobulin, it was progressive for at least 25 days until the start of prednisolone (PSL) administration, after which it remarkably improved. The neuropathy further improved after allogeneic bone marrow transplantation (BMT). The present patient's clinical course is not consistent with that of typical Guillain-Barré syndrome. This case suggests that EBV-T/NK-LPD can cause progressive immune-mediated neuropathy as a result of chronic EBV antigen presentation and can be treated with PSL and BMT.

Evaluation of innate and adaptive immunity contributing to the antitumor effects of PD1 blockade in an orthotopic murine model of pancreatic cancer

PubMed Central

D'Alincourt Salazar, Marcela; Manuel, Edwin R.; Tsai, Weimin; D'Apuzzo, Massimo; Goldstein, Leanne; Blazar, Bruce R.; Diamond, Don J.

2016-01-01

ABSTRACT Despite the clinical success of anti-PD1 antibody (α-PD1) therapy, the immune mechanisms contributing to the antineoplastic response remain unclear. Here, we describe novel aspects of the immune response involved in α-PD1-induced antitumor effects using an orthotopic KrasG12D/p53R172H/Pdx1-Cre (KPC) model of pancreatic ductal adenocarcinoma (PDA). We found that positive therapeutic outcome involved both the innate and adaptive arms of the immune system. Adoptive transfer of total splenocytes after short-term (3 d) but not long-term (28 d) PD1 blockade significantly extended survival of non-treated tumor-bearing recipient mice. This protective effect appeared to be mostly mediated by T cells, as adoptive transfer of purified natural killer (NK) cells and/or granulocyte receptor 1 (Gr1)+ cells or splenocytes depleted of Gr1+ cells and NK cells did not exhibit transferrable antitumor activity following short-term PD1 blockade. Nevertheless, splenic and tumor-derived CD11b+Gr1+ cells and NK cells showed significant persistence of α-PD1 bound to these cells in the treated primary recipient mice. We observed that short-term inhibition of PD1 signaling modulated the profiles of multifunctional cytokines in the tumor immune-infiltrate, including downregulation of vascular endothelial growth factor A (VEGF-A). Altogether, the data suggest that systemic blockade of PD1 results in rapid modulation of antitumor immunity that differs in the tumor microenvironment (TME) when compared to the spleen. These results demonstrate a key role for early immune-mediated events in controlling tumor progression in response to α-PD1 treatment and warrant further investigation into the mechanisms governing responses to the therapy at the innate-adaptive immune interface. PMID:27471630

Expression of cellular protective proteins SIRT1, HSP70 and SOD2 correlates with age and is significantly higher in NK cells of the oldest seniors.

PubMed

Kaszubowska, Lucyna; Foerster, Jerzy; Kaczor, Jan Jacek; Schetz, Daria; Ślebioda, Tomasz Jerzy; Kmieć, Zbigniew

2017-01-01

NK cells are key effector lymphocytes of innate immunity provided with constitutive cytolytic activity, however, their role in human ageing is not entirely understood. The study aimed to analyze the expression of proteins involved in cellular stress response sirtuin 1 (SIRT1), heat shock protein 70 (HSP70) and manganese superoxide dismutase (SOD2) in non-stimulated NK cells of the oldest seniors ( n  = 25; aged over 85; mean age 88 years) and compare with NK cells of the old ( n  = 30; aged under 85; mean age 76 years) and the young ( n  = 32; mean age 21 years) to find potential relationships between the level of expression of these proteins in NK cells and longevity. The concentration of carbonyl groups and 8-isoprostanes in NK cell lysates reflecting the level of oxidative stress was also measured. The group of the oldest seniors differed from the other age groups by significantly higher percentage of NK cells expressing SIRT1, HSP70 and SOD2. The concentration of both carbonyl groups and 8-isoprostanes in NK cell extracts remained within the normal range in all age groups. The percentage of NK cells with the expression of, respectively, SIRT1, HSP70 and SOD2 correlated positively with age. Some correlations between expression levels of particular protective proteins SIRT1, HSP70 and SOD2 were observed in the study population. The increased expression of cellular protective proteins SIRT1, HSP70 and SOD2 in NK cells of the oldest seniors seems to correspond to longevity and the observed correlations may suggest the involvement of these proteins in establishing NK cell homeostasis specific for healthy ageing process.

[Correlations between cellular immunity and invasiveness in differentiated thyroid cancer].

PubMed

Han, Ting; Liang, Jun; Meng, Chao; Yang, Ke; Li, Xiao-yi; Lin, Yan-song

2014-02-01

To investigate the relationship between the immunity and invasiveness in differentiated thyroid cancer (DTC). Totally 74 DTC who were treated in Peking Union Medical College Hospital from September 2012 to December 2012 were enrolled in this study. These 74 patients were divided into membrane invasion group (n=36) and without membrane invasion group (n=38); also, they were divided into distant metastasis group (n=18) and without distant metastasis group (n=56). Natural killer (NK) cells and T-cell subsets were chosen as indicators for cellular immunity to investigate the correlation between cellular immunity and invasiveness in DTC. Univariate analysis showed that the membrane invasion (Χ(2)=12.175, P=0.000) and distant metastasis (Χ(2)=8.139, P=0.006) correlated with cell immunity, whereas distant metastasis correlated with lymphocytic thyroiditis (Χ(2)=7.094, P=0.008). Further investigation shows that distant metastasis was associated with the percentage of CD8+T cell subgroup (Χ(2)=5.429, P=0.020), and membrane invasion was significantly associated with NK cells (Χ(2)=2.445, P=0.018) and CD4/CD8 disorder subgroup (Χ(2)=8.079, P=0.002). Multivariate analysis showed that cell immunity disorder was a risk factor for membrane invasion [OR=5.701,95%CI(2.075~15.666), P=0.001] and distant metastasis [OR=5.063,95%CI (1.571~16.320), P=0.008]. Further analysis showed that CD8+T cell was a risk factor for metastasis [OR=2.236,95%CI( 1.084~4.613), P=0.029], and CD4/CD8 disorders were the risk factors for membrane invasion [OR=2.802,95%CI(1.257~6.244), P=0.012]. Cell immunity in thyroid cancer has close relationship with membrane invasion and distant metastasis, especially when the percentage of CD8+T cells decreases and when the NK cells and CD4/CD8 are abnormal, which may lead to membrane invasion and distant metastasis.

Escherichia coli Nissle 1917 protects gnotobiotic pigs against human rotavirus by modulating pDC and NK-cell responses.

PubMed

Vlasova, Anastasia N; Shao, Lulu; Kandasamy, Sukumar; Fischer, David D; Rauf, Abdul; Langel, Stephanie N; Chattha, Kuldeep S; Kumar, Anand; Huang, Huang-Chi; Rajashekara, Gireesh; Saif, Linda J

2016-10-01

Lactobacillus rhamnosus GG (LGG), a gram-positive lactic acid bacterium, is one of the most widely used probiotics; while fewer gram-negative probiotics including Escherichia coli Nissle 1917 (EcN) are characterized. A mechanistic understanding of their individual and interactive effects on human rotavirus (HRV) and immunity is lacking. In this study, noncolonized, EcN-, LGG-, and EcN + LGG-colonized neonatal gnotobiotic (Gn) pigs were challenged with HRV. EcN colonization is associated with a greater protection against HRV, and induces the highest frequencies of plasmacytoid dendritic cells (pDCs), significantly increased NK-cell function and decreased frequencies of apoptotic and TLR4 + mononuclear cells (MNCs). Consistent with the highest NK-cell activity, splenic CD172 + MNCs (DC enriched fraction) of EcN-colonized pigs produced the highest levels of IL-12 in vitro. LGG colonization has little effect on the above parameters, which are intermediate in EcN + LGG-colonized pigs, suggesting that probiotics modulate each other's effects. Additionally, in vitro EcN-treated splenic or intestinal MNCs produce higher levels of innate, immunoregulatory and immunostimulatory cytokines, IFN-α, IL-12, and IL-10, compared to MNCs of pigs treated with LGG. These results indicate that the EcN-mediated greater protection against HRV is associated with potent stimulation of the innate immune system and activation of the DC-IL-12-NK immune axis. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Aberrant apoptotic machinery confers melanoma dual resistance to BRAFV600E inhibitor and immune effector cells: immunosensitization by a histone deacetylase inhibitor

PubMed Central

Jazirehi, Ali R; Nazarian, Ramin; Torres-Collado, Antoni Xavier; Economou, James S

2014-01-01

BRAFV600E-inhibitors (BRAFi; e.g., vemurafenib) and modern immune-based therapies such as PD-1/PD-L1 and CTLA-4 checkpoints blockade and adoptive cell transfer (ACT) have significantly improved the care of melanoma patients. Having these two effective (BRAFi and immunotherapy) therapies raises the question whether there is a rational biological basis for using them in combination. We developed an in vitro model to determine whether tumor resistance mechanisms to a small molecule inhibitor of a driver oncogene, and to cytotoxic T lymphocyte (CTL)- and natural killer (NK) cell-delivered apoptotic death signals were exclusive or intersecting. We generated melanoma sublines resistant to BRAFi vemurafenib and to CTL recognizing the MART-1 melanoma antigen. Vemurafenib-resistant (VemR) sublines were cross-resistant to MART CTL and NK cells indicating that a common apoptotic pathway governing tumor response to both modalities was disrupted. Pretreatment of VemR melanomas with a histone deacetylase inhibitor (HDACi) restored sensitivity to MART CTL and NK apoptosis by skewing the apoptotic gene programs towards a proapoptotic phenotype. Our in vitro findings suggest that during the course of acquisition of BRAFi resistance, melanomas develop cross-resistance to CTL- and NK-killing. Further, aberrant apoptotic pathways, amenable by an FDA-approved chromatin remodeling drug, regulate tumor resistance mechanisms to immune effector cells. These results may provide rational molecular basis for further investigations to combine these therapies clinically. PMID:24660121

CD56bright NK cells exhibit potent antitumor responses following IL-15 priming

PubMed Central

Wagner, Julia A.; Berrien-Elliott, Melissa M.; Schneider, Stephanie E.; Leong, Jeffrey W.; Sullivan, Ryan P.; Jewell, Brea A.; Becker-Hapak, Michelle; Abdel-Latif, Sara; Ireland, Aaron R.; Jaishankar, Devika; King, Justin A.; Vij, Ravi; Clement, Dennis; Goodridge, Jodie; Malmberg, Karl-Johan; Wong, Hing C.; Fehniger, Todd A.

2017-01-01

NK cells, lymphocytes of the innate immune system, are important for defense against infectious pathogens and cancer. Classically, the CD56dim NK cell subset is thought to mediate antitumor responses, whereas the CD56bright subset is involved in immunomodulation. Here, we challenge this paradigm by demonstrating that brief priming with IL-15 markedly enhanced the antitumor response of CD56bright NK cells. Priming improved multiple CD56bright cell functions: degranulation, cytotoxicity, and cytokine production. Primed CD56bright cells from leukemia patients demonstrated enhanced responses to autologous blasts in vitro, and primed CD56bright cells controlled leukemia cells in vivo in a murine xenograft model. Primed CD56bright cells from multiple myeloma (MM) patients displayed superior responses to autologous myeloma targets, and furthermore, CD56bright NK cells from MM patients primed with the IL-15 receptor agonist ALT-803 in vivo displayed enhanced ex vivo functional responses to MM targets. Effector mechanisms contributing to IL-15–based priming included improved cytotoxic protein expression, target cell conjugation, and LFA-1–, CD2-, and NKG2D-dependent activation of NK cells. Finally, IL-15 robustly stimulated the PI3K/Akt/mTOR and MEK/ERK pathways in CD56bright compared with CD56dim NK cells, and blockade of these pathways attenuated antitumor responses. These findings identify CD56bright NK cells as potent antitumor effectors that warrant further investigation as a cancer immunotherapy. PMID:28972539

Determining immune components necessary for progression of pigment dispersing disease to glaucoma in DBA/2J mice

PubMed Central

2014-01-01

Background The molecular mechanisms causing pigment dispersion syndrome (PDS) and the pathway(s) by which it progresses to pigmentary glaucoma are not known. Mutations in two melanosomal protein genes (Tyrp1 b and Gpnmb R150X ) are responsible for pigment dispersing iris disease, which progresses to intraocular pressure (IOP) elevation and subsequent glaucoma in DBA/2J mice. Melanosomal defects along with ocular immune abnormalities play a role in the propagation of pigment dispersion and progression to IOP elevation. Here, we tested the role of specific immune components in the progression of the iris disease and high IOP. Results We tested the role of NK cells in disease etiology by genetically modifying the B6.D2-Gpnmb R150X Tyrp1 b strain, which develops the same iris disease as DBA/2J mice. Our findings demonstrate that neither diminishing NK mediated cytotoxic activity (Prf1 mutation) nor NK cell depletion (Il2rg mutation) has any influence on the severity or timing of Gpnmb R150X Tyrp1 b mediated iris disease. Since DBA/2J mice are deficient in CD94, an important immune modulator that often acts as an immune suppressor, we generated DBA/2J mice sufficient in CD94. Sufficiency of CD94 failed to alter either the iris disease or the subsequent IOP elevation. Additionally CD94 status had no detected effect on glaucomatous optic nerve damage. Conclusion Our previous data implicate immune components in the manifestation of pigment dispersion and/or IOP elevation in DBA/2J mice. The current study eliminates important immune components, specifically NK cells and CD94 deficiency, as critical in the progression of iris disease and glaucoma. This narrows the field of possible immune components responsible for disease progression. PMID:24678736

Lipoic acid stimulates cAMP production via the EP2 and EP4 prostanoid receptors and inhibits IFN gamma synthesis and cellular cytotoxicity in NK cells

PubMed Central

Salinthone, Sonemany; Schillace, Robynn V.; Marracci, Gail H.; Bourdette, Dennis N.; Carr, Daniel W.

2008-01-01

The antioxidant lipoic acid (LA) treats and prevents the animal model of multiple sclerosis (MS), experimental autoimmune encephalomyelitis (EAE). In an effort to understand the therapeutic potential of LA in MS, we sought to define the cellular mechanisms that mediate the effects of LA on human natural killer (NK) cells, which are important in innate immunity as the first line of defense against invading pathogens and tumor cells. We discovered that LA stimulates cAMP production in NK cells in a dose-dependent manner. Studies using pharmacological inhibitors and receptor transfection experiments indicate that LA stimulates cAMP production via activation of the EP2 and EP4 prostanoid receptors and adenylyl cyclase. In addition, LA suppressed interleukin (IL)-12/IL-18 induced IFNγ secretion and cytotoxicity in NK cells. These novel findings suggest that LA may inhibit NK cell function via the cAMP signaling pathway. PMID:18562016

Inflammatory Ly6Chigh Monocytes Protect against Candidiasis through IL-15-Driven NK Cell/Neutrophil Activation.

PubMed

Domínguez-Andrés, Jorge; Feo-Lucas, Lidia; Minguito de la Escalera, María; González, Leticia; López-Bravo, María; Ardavín, Carlos

2017-06-20

Neutrophils play a crucial role in defense against systemic candidiasis, a disease associated with a high mortality rate in patients receiving immunosuppressive therapy, although the early immune mechanisms that boost the candidacidal activity of neutrophils remain to be defined in depth. Here, we used a murine model of systemic candidiasis to explore the role of inflammatory Ly6C high monocytes in NK cell-mediated neutrophil activation during the innate immune response against C. albicans. We found that efficient anti-Candida immunity required a collaborative response between the spleen and kidney, which relied on type I interferon-dependent IL-15 production by spleen inflammatory Ly6C high monocytes to drive efficient activation and GM-CSF release by spleen NK cells; this in turn was necessary to boost the Candida killing potential of kidney neutrophils. Our findings unveil a role for IL-15 as a critical mediator in defense against systemic candidiasis and hold promise for the design of IL-15-based antifungal immunotherapies. Copyright © 2017 Elsevier Inc. All rights reserved.

Circulating innate lymphoid cells are unchanged in response to DAC HYP therapy.

PubMed

Gillard, Geoffrey O; Saenz, Steven A; Huss, David J; Fontenot, Jason D

2016-05-15

Innate lymphoid cells (ILCs) play an important role in immunity, inflammation, and tissue remodeling and their dysregulation is implicated in autoimmune and inflammatory disorders. We analyzed the impact of daclizumab, a humanized monoclonal anti-CD25 antibody, on circulating natural killer (NK) cells and ILCs in a cohort of multiple sclerosis patients. An increase in CD56(bright) NK cells and CD56(hi)CD16(intermediate) transitional NK cells was observed. No significant change in total ILCs or major ILC subpopulations was observed. These results refine our understanding of the impact of daclizumab on innate lymphoid cell populations. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

Attacking Postoperative Metastases using Perioperative Oncolytic Viruses and Viral Vaccines

PubMed Central

Tai, Lee-Hwa; Auer, Rebecca

2014-01-01

Surgical resection of solid primary malignancies is a mainstay of therapy for cancer patients. Despite being the most effective treatment for these tumors, cancer surgery has been associated with impaired metastatic clearance due to immunosuppression. In preclinical surgery models and human cancer patients, we and others have demonstrated a profound suppression of both natural killer (NK) and T cell function in the postoperative period and this plays a major role in the enhanced development of metastases following surgery. Oncolytic viruses (OV) were originally designed to selectively infect and replicate in tumors, with the primary objective of directly lysing cancer cells. It is becoming increasingly clear, however, that OV infection results in a profound inflammatory reaction within the tumor, initiating innate and adaptive immune responses against it that is critical for its therapeutic benefit. This anti-tumor immunity appears to be mediated predominantly by NK and cytotoxic T cells. In preclinical models, we found that preoperative OV prevents postoperative NK cell dysfunction and attenuates tumor dissemination. Due to theoretical safety concerns of administering live virus prior to surgery in cancer patients, we characterized safe, attenuated versions of OV, and viral vaccines that could stimulate NK cells and reduce metastases when administered in the perioperative period. In cancer patients, we observed that in vivo infusion with oncolytic vaccinia virus and ex vivo stimulation with viral vaccines promote NK cell activation. These preclinical studies provide a novel and clinically relevant setting for OV therapy. Our challenge is to identify safe and promising OV therapies that will activate NK and T cells in the perioperative period preventing the establishment of micrometastatic disease in cancer patients. PMID:25161958

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection

PubMed Central

Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M.; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S.; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

2014-01-01

SUMMARY Primary infection with the human oncogenic Epstein Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion, which predisposes for the development of distinct EBV-associated lymphomas. It remains unclear why some individuals experience this symptomatic primary EBV infection, while the majority acquires the virus asymptomatically. Using a mouse model with reconstituted human immune system components, we show here that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis, mainly due to loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. PMID:24360958

Early detection of tumor cells by innate immune cells leads to T(reg) recruitment through CCL22 production by tumor cells.

PubMed

Faget, Julien; Biota, Cathy; Bachelot, Thomas; Gobert, Michael; Treilleux, Isabelle; Goutagny, Nadège; Durand, Isabelle; Léon-Goddard, Sophie; Blay, Jean Yves; Caux, Christophe; Ménétrier-Caux, Christine

2011-10-01

In breast carcinomas, patient survival seems to be negatively affected by the recruitment of regulatory T cells (T(reg)) within lymphoid aggregates by CCL22. However, the mechanisms underpinning this process, which may be of broader significance in solid tumors, have yet to be described. In this study, we determined how CCL22 production is controlled in tumor cells. In human breast carcinoma cell lines, CCL22 was secreted at low basal levels that were strongly increased in response to inflammatory signals [TNF-α, IFN-γ, and interleukin (IL)-1β], contrasting with CCL17. Primary breast tumors and CD45(+) infiltrating immune cells appeared to cooperate in driving CCL22 secretion, as shown clearly in cocultures of breast tumor cell lines and peripheral blood mononuclear cells (PBMC) or their supernatants. We determined that monocyte-derived IL-1β and TNF-α are key players as monocyte depletion or neutralization of these cytokines attenuated secretion of CCL22. However, when purified monocytes were used, exogenous human IFN-γ was also required to generate this response suggesting a role for IFN-γ-producing cells within PBMCs. In this setting, we found that human IFN-γ could be replaced by the addition of (i) IL-2 or K562-activated natural killer (NK) cells or (ii) resting NK cells in the presence of anti-MHC class I antibody. Taken together, our results show a dialogue between NK and tumor cells leading to IFN-γ secretion, which in turn associates with monocyte-derived IL-1β and TNF-α to drive production of CCL22 by tumor cells and subsequent recruitment of T(reg). As one validation of this conclusion in primary breast tumors, we showed that NK cells and macrophages tend to colocalize within tumors. In summary, our findings suggest that at early times during tumorigenesis, the detection of tumor cells by innate effectors (monocytes and NK cells) imposes a selection for CCL22 secretion that recruits T(reg) to evade this early antitumor immune response.

Influence of breast milk polyamines on suckling rat immune system maturation.

PubMed

Pérez-Cano, Francisco J; González-Castro, Ana; Castellote, Cristina; Franch, Angels; Castell, Margarida

2010-02-01

The aim of this study was to ascertain whether the supplementation of polyamines present in breast milk, i.e. spermine (SPM) and spermidine (SPD), influenced the post-natal maturation of the systemic and intestinal immune system in rats. From birth, pups daily received SPM or SPD. At 5, 11 and 18 days old, small intestine intraepithelial lymphocytes (IEL), lamina propria lymphocytes (LPL) and splenocytes were phenotypically characterized. SPM and, less evidently, SPD accelerated the maturation of CD8+ IEL, and enhanced the presence of intraepithelial NK cells and IEL related with specific immune responses on the proximal and distal small intestine, respectively. Polyamines increased the percentage of more mature CD4+ LPL and enhanced the early presence of splenic B cells and, later, that of NK cells. However, no effect on Ig-secretory function was detected. These results suggest that breast milk polyamines improve the maturation of the rat intestinal and systemic immune system.

The role of natural killer cells in autoimmune blistering diseases.

PubMed

Zakka, L R; Fradkov, E; Keskin, D B; Tabansky, I; Stern, J N H; Ahmed, A R

2012-02-01

The major focus of this paper is to describe and evaluate current information on the role of natural killer cells (NK cells) in the pathogenesis of blistering diseases. Until now, only pemphigus vulgaris (PV) has been studied. One co-culture study demonstrated that CD4+ T cells from the peripheral blood or perilesional skin of patients with active disease proliferate and secrete cytokines in the presence of major histocompatibility class II-expressing NK cells loaded with antigenic desmoglein self-peptides. Another study showed that NK cells can contribute to a T helper type 2-biased immune response through impaired interleukins (IL)-12 signaling and upregulation of IL, IL-10 and IL-5. Although significant data on other blistering diseases are unavailable at present, some studies implicate NK cells in disease progression. For instance, information on the role of NK cells in psoriasis and their production of tumor necrosis factor-α (TNF-α) will be provided since several TNF-α-inhibitors are used in its treatment. Studies on alopecia areata are also included in this paper because NK cells seem to play a key role in its pathogenesis. This review highlights the potential importance of NK cells and NKT cells as members of the large repertoire of cells and soluble mediators that play a critical role in pathogenesis of blistering diseases and other autoimmune diseases involving the skin. Therefore, the authors advocate a greater focus and interest on the study of the interaction of NK cells and the skin.

TLR4 plays a crucial role in MSC-induced inhibition of NK cell function

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lu, Ying; Liu, Jin; Liu, Yang

2015-08-21

Mesenchymal stem cells (MSC) are a kind of stromal cell within the tumor microenvironment. In our research, MSC derived from acute myeloid leukemia patients' bone marrow (AML-MSC) and lung cancer tissues (LC-MSC) as well as normal bone marrow-derived MSC (BM-MSC) cultured in conditioned medium of HeLa cells were found to have higher expressions of Toll-like receptor (TLR4) mRNA compared with BM-MSC. The sorted TLR4-positive MSC (TLR4+ MSC) differed in cytokine (interleukin-6, interleukin-8, and monocyte chemoattractant protein-1) secretion from those of unsorted MSC. MSC was reported to inhibit natural killer (NK) cell proliferation and function. In this research, we confirmed thatmore » TLR4+ MSC aggravate this suppression. Furthermore, when TLR4 in the sorted cells were stimulated by LPS or following blocked by antibody, the suppression on NK cell proliferation and cytotoxicity were more intensive or recovered respectively. Compared to unsorted MSC, NKG2D receptor expression on NK cells were also inhibited by TLR4+ MSC. These findings suggest that activation of TLR4 pathway is important for TLR4+ MSC and MSC to obstruct anti-tumor immunity by inhibiting NK cell function, which may provide a potential stroma-targeted tumor therapy. - Highlights: • TLR4+ MSC inhibit NK cell proliferation in vivo and in vitro. • TLR4+ MSC inhibit NKG2D expression on NK cells and NK cell cytotoxicity. • The distinguished cytokine expression of TLR4+ MSC may contribute to the inhibition on NK cell function.« less

A correlate of HIV-1 control consisting of both innate and adaptive immune parameters best predicts viral load by multivariable analysis in HIV-1 infected viremic controllers and chronically-infected non-controllers.

PubMed

Tomescu, Costin; Liu, Qin; Ross, Brian N; Yin, Xiangfan; Lynn, Kenneth; Mounzer, Karam C; Kostman, Jay R; Montaner, Luis J

2014-01-01

HIV-1 infected viremic controllers maintain durable viral suppression below 2000 copies viral RNA/ml without anti-retroviral therapy (ART), and the immunological factor(s) associated with host control in presence of low but detectable viral replication are of considerable interest. Here, we utilized a multivariable analysis to identify which innate and adaptive immune parameters best correlated with viral control utilizing a cohort of viremic controllers (median 704 viral RNA/ml) and non-controllers (median 21,932 viral RNA/ml) that were matched for similar CD4+ T cell counts in the absence of ART. We observed that HIV-1 Gag-specific CD8+ T cell responses were preferentially targeted over Pol-specific responses in viremic controllers (p = 0.0137), while Pol-specific responses were positively associated with viral load (rho = 0.7753, p = 0.0001, n = 23). Viremic controllers exhibited significantly higher NK and plasmacytoid dendritic cells (pDC) frequency as well as retained expression of the NK CD16 receptor and strong target cell-induced NK cell IFN-gamma production compared to non-controllers (p<0.05). Despite differences in innate and adaptive immune function however, both viremic controllers (p<0.05) and non-controller subjects (p<0.001) exhibited significantly increased CD8+ T cell activation and spontaneous NK cell degranulation compared to uninfected donors. Overall, we identified that a combination of innate (pDC frequency) and adaptive (Pol-specific CD8+ T cell responses) immune parameters best predicted viral load (R2 = 0.5864, p = 0.0021, n = 17) by a multivariable analysis. Together, this data indicates that preferential Gag-specific over Pol-specific CD8+ T cell responses along with a retention of functional innate subsets best predict host control over viral replication in HIV-1 infected viremic controllers compared to chronically-infected non-controllers.

Lower numbers of circulating natural killer T (NK T) cells in individuals with human T lymphotropic virus type 1 (HTLV-1) associated neurological disease

PubMed Central

Ndhlovu, L C; Snyder-Cappione, J E; Carvalho, K I; Leal, F E; Loo, C P; bruno, F R; Jha, A R; Devita, D; Hasenkrug, A M; Barbosa, H M R; Segurado, A C; Nixon, D F; Murphy, E L; Kallas, E G

2009-01-01

Human T lymphotropic virus type 1 (HTLV-1) infects 10–20 million people worldwide. The majority of infected individuals are asymptomatic; however, approximately 3% develop the debilitating neurological disease HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). There is also currently no cure, vaccine or effective therapy for HTLV-1 infection, and the mechanisms for progression to HAM/TSP remain unclear. NK T cells are an immunoregulatory T cell subset whose frequencies and effector functions are associated critically with immunity against infectious diseases. We hypothesized that NK T cells are associated with HAM/TSP progression. We measured NK T cell frequencies and absolute numbers in individuals with HAM/TSP infection from two cohorts on two continents: São Paulo, Brazil and San Francisco, CA, USA, and found significantly lower levels when compared with healthy subjects and/or asymptomatic carriers. Also, the circulating NK T cell compartment in HAM/TSP subjects is comprised of significantly more CD4+ and fewer CD8+ cells than healthy controls. These findings suggest that lower numbers of circulating NK T cells and enrichment of the CD4+ NK T subset are associated with HTLV-1 disease progression. PMID:19778295

A role for the substance P/NK-1 receptor complex in cell proliferation and apoptosis in oral lichen planus.

PubMed

González Moles, M A; Esteban, F; Ruiz-Avila, I; Gil Montoya, J A; Brener, S; Bascones-Martínez, A; Muñoz, M

2009-03-01

To determine whether substance P (SP) and NK-1 receptor (NK-1R) are expressed in oral lichen planus (OLP) and are related to cell proliferation and apoptosis in this disease. Tissue samples from 50 OLP patients and 26 healthy controls were studied. Immunohistochemistry was performed with anti-SP, anti-NK-1R, anti-ki-67 and anti-caspase-3 monoclonal antibodies and the clinical and pathological data of the OLP patients were evaluated. With the exception of NK-1R expression in epithelial cell membrane and cytoplasm, all markers were more frequently present in OLP patients than in controls (P < 0.05). Higher cytoplasmatic expression of NK-1R was associated with higher epithelial expression of caspase-3 (P < 0.05). Higher epithelial expression of NK-1R and SP was associated with higher suprabasal and basal epithelial expression of ki-67 (P < 0.05 and P < 0.005, respectively). Actions of the SP/NK-1R complex may contribute to the immune disorder underlying OLP and trigger stimuli to induce cell proliferation. These results indicate that this complex might play a role in the malignant transformation of OLP.

Simian immunodeficiency virus (SIV)/immunoglobulin G immune complexes in SIV-infected macaques block detection of CD16 but not cytolytic activity of natural killer cells.

PubMed

Wei, Qing; Stallworth, Jackie W; Vance, Patricia J; Hoxie, James A; Fultz, Patricia N

2006-07-01

Natural killer cells are components of the innate immune system that play an important role in eliminating viruses and malignant cells. Using simian immunodeficiency virus (SIV) infection of macaques as a model, flow cytometry revealed a gradual loss of CD16+ NK cell numbers that was associated with disease progression. Of note, the apparent loss of NK cells was detected in whole-blood samples but not in isolated peripheral blood mononuclear cells (PBMC), suggesting that an inhibitor(s) of the antibody used to detect CD16, the low-affinity immunoglobulin G (IgG) receptor, was present in blood but was removed during PBMC isolation. (Actual decreases in CD16+ cell numbers in PBMC generally were not detected until animals became lymphopenic.) The putative decrease in CD16+ cell numbers in whole blood correlated with increasing SIV-specific antibody titers and levels of plasma virion RNA. With the addition of increasing amounts of plasma from progressor, but not nonprogressor, macaques to PBMC from an uninfected animal, the apparent percentage of CD16+ cells and the mean fluorescence intensity of antibodies binding to CD16 declined proportionately. A similar decrease was observed with the addition of monomeric IgG (mIgG) and IgG immune complexes (IgG-ICs) purified from the inhibitory plasma samples; some of the ICs contained SIV p27(gag) antigen and/or virions. Of interest, addition of purified IgG/IgG-ICs to NK cell lytic assays did not inhibit killing of K562 cells. These results indicate that during progressive SIV and, by inference, human immunodeficiency virus disease, CD16+ NK cell numbers can be underestimated, or the cells not detected at all, when one is using a whole-blood fluorescence-activated cell sorter assay and a fluorochrome-labeled antibody that can be blocked by mIgG or IgG-ICs. Although this blocking had no apparent effect on NK cell activity in vitro, the in vivo effects are unknown.

Endocytosis as a mechanism of regulating natural killer cell function: unique endocytic and trafficking pathway for CD94/NKG2A.

PubMed

Peruzzi, Giovanna; Masilamani, Madhan; Borrego, Francisco; Coligan, John E

2009-01-01

Natural killer (NK) cells are lymphocytes generally recognized as sentinels of the innate immune system due to their inherent capacity to deal with diseased (stressed) cells, including malignant and infected. This ability to recognize many potentially pathogenic situations is due to the expression of a diverse panel of activation receptors. Because NK cell activation triggers an aggressive inflammatory response, it is important to have a means of throttling this response. Hence, NK cells also express a panel of inhibitory receptors that recognize ligands expressed by "normal" cells. Little or nothing is known about the endocytosis and trafficking of NK cell receptors, which are of great relevance to understanding how NK cells maintain the appropriate balance of activating and inhibitory receptors on their cell surface. In this review, we focus on the ITIM-containing inhibitory receptor CD94/NKG2A showing that it is endocytosed by a previously undescribed macropinocytic-like process that may be related to the maintenance of its surface expression.

Novel Therapeutic Strategies for Solid Tumor Based on Body's Intrinsic Antitumor Immune System.

PubMed

Duan, Haifeng

2018-05-22

The accumulation of mutated somatic cells due to the incompetency of body's immune system may lead to tumor onset. Therefore, enhancing the ability of the system to eliminate such cells should be the core of tumor therapy. The intrinsic antitumor immunity is triggered by tumor-specific antigens (TSA) or TSA-sensitized dendritic cells (DC). Once initiated, specific anti-tumor antibodies are produced and tumor-specific killer immune cells, including cytotoxic T lymphocytes (CTL), NK cells, and macrophages, are raised or induced. Several strategies may enhance antitumor action of immune system, such as supplying tumor-targeted antibody, activating T cells, enhancing the activity and tumor recognition of NK cells, promoting tumor-targeted phagocytosis of macrophages, and eliminating the immunosuppressive myeloid-derived suppressor cells (MDSCs) and Treg cells. Apart from the immune system, the removal of tumor burden still needs to be assisted by drugs, surgery or radiation. And the body's internal environment and tumor microenvironment should be improved to recover immune cell function and prevent tumor growth. Multiple microenvironment modulatory therapies may be applied, including addressing hypoxia and oxidative stress, correcting metabolic disorders, and controlling chronic inflammation. Finally, to cure tumor and prevent tumor recurrence, repairing or supporting therapy that consist of tissue repair and nutritional supplement should be applied properly. © 2018 The Author(s). Published by S. Karger AG, Basel.

Enriched environment reduces glioma growth through immune and non-immune mechanisms in mice

PubMed Central

Garofalo, Stefano; D’Alessandro, Giuseppina; Chece, Giuseppina; Brau, Frederic; Maggi, Laura; Rosa, Alessandro; Porzia, Alessandra; Mainiero, Fabrizio; Esposito, Vincenzo; Lauro, Clotilde; Benigni, Giorgia; Bernardini, Giovanni; Santoni, Angela; Limatola, Cristina

2015-01-01

Mice exposed to standard (SE) or enriched environment (EE) were transplanted with murine or human glioma cells and differences in tumour development were evaluated. We report that EE exposure affects: (i) tumour size, increasing mice survival; (ii) glioma establishment, proliferation and invasion; (iii) microglia/macrophage (M/Mφ) activation; (iv) natural killer (NK) cell infiltration and activation; and (v) cerebral levels of IL-15 and BDNF. Direct infusion of IL-15 or BDNF in the brain of mice transplanted with glioma significantly reduces tumour growth. We demonstrate that brain infusion of IL-15 increases the frequency of NK cell infiltrating the tumour and that NK cell depletion reduces the efficacy of EE and IL-15 on tumour size and of EE on mice survival. BDNF infusion reduces M/Mφ infiltration and CD68 immunoreactivity in tumour mass and reduces glioma migration inhibiting the small G protein RhoA through the truncated TrkB.T1 receptor. These results suggest alternative approaches for glioma treatment. PMID:25818172

Selective Blockade of Human Natural Killer Cells by a Monoclonal Antibody

NASA Astrophysics Data System (ADS)

Newman, Walter

1982-06-01

A murine monoclonal antibody, 13.1, which blocks human natural killer (NK) cell-mediated lysis, has been developed. Hybridoma 13.1 was derived by fusion of NS-1 cells with spleen cells from mice immunized with an enriched population of NK cells. Supernatants of growing hybridomas were screened for their ability to block NK cell-mediated lysis of K562 targets. Antibody 13.1 is an IgG1 with a single light chain type and it does not fix complement. The 13.1 antigen is expressed on all peripheral blood mononuclear cells, with an antigen density approximately 1/30th that of HLA antigen heavy chain. Pretreatment and washing experiments revealed that inhibition of cytotoxicity occurred at the effector cell level only. Significant blocking was achieved with nanogram quantities of antibody and was not due to toxic effects on NK cells. Likewise, controls with other antibodies of the same subclass demonstrated that blocking was not a consequence of mere binding to NK cells. When a panel of 17 NK cell-susceptible targets was tested, the lysis of only 5 of these was blocked, namely K562, HL-60, KG-1, Daudi, and HEL, a human erythroleukemic cell line. The lysis of 12 human B cell and T cell line targets was not inhibited. In addition to the demonstration that the 13.1 antigen is a crucial cell surface structure involved in NK lysis, a heterogeneity of target cell recognition has been revealed that argues for the proposition that individual NK cells have multiple recognitive capabilities.

Physical Inactivity and Unhealthy Metabolic Status Are Associated with Decreased Natural Killer Cell Activity.

PubMed

Jung, Yoon Suk; Park, Jung Ho; Park, Dong Il; Sohn, Chong Il; Lee, Jae Myun; Kim, Tae Il

2018-06-01

Several studies have reported relationships among physical activity, healthy metabolic status, and increased natural killer (NK) cell activity. However, large-scale data thereon are lacking. Thus, the present study aimed to assess NK cell activity according to physical activity and metabolic status. A cross-sectional study was performed on 12014 asymptomatic examinees. Using a patented stimulatory cytokine, NK cell activity was quantitated by the amount of interferon-γ secreted into the plasma by NK cells. Physical activity levels were assessed using the validated Korean version of the International Physical Activity Questionnaire Short Form. The physically inactive group showed lower NK cell activity than the minimally active group (median, 1461 vs. 1592 pg/mL, p<0.001) and health-enhancing physically active group (median, 1461 vs. 1712 pg/mL, p=0.001). Compared to women with a body mass index (BMI) of 18.5-27.5 kg/m², those with a BMI <18.5 kg/m² had significantly lower NK cell activity (1356 vs. 1024 g/mL, p<0.001), and those with a BMI ≥27.5 kg/m² tended to have lower NK cell activity (1356 vs. 1119 g/mL, p=0.070). Subjects with high hemoglobin A1c levels and low high-density lipoprotein cholesterol levels, as well as men with high blood pressure and women with high triglyceride levels, exhibited lower NK cell activity. Moreover, physical inactivity and metabolic abnormalities were independently associated with low NK cell activity, even after adjusting for confounders. Physical inactivity and metabolic abnormalities are associated with reduced NK cell activity. Immune systems may become altered depending on physical activity and metabolic status. © Copyright: Yonsei University College of Medicine 2018.

Mediating Effects of Patients' Stigma and Self-Efficacy on Relationships Between Doctors' Empathy Abilities and Patients' Cellular Immunity in Male Breast Cancer Patients.

PubMed

Yang, Ningxi; Cao, Yingnan; Li, Xiaoyan; Li, Shiyue; Yan, Hong; Geng, Qingshan

2018-06-12

BACKGROUND Doctors' empathy is closely related to patients' health. This study aimed to examine whether patients' stigma and self-efficacy play a mediating role in the relationship between doctors' empathy abilities and patients' cellular immunity in male patients with breast cancer. MATERIAL AND METHODS Doctors' empathy scores and patients' demographic data, disease condition, stigma, and self-efficacy were measured. Patient T cell subset was tested at admission and 3 months after the operation and was compared by paired t test. The multivariate linear regression model was applied to analyze the factors influencing the immune index. Pearson correlation analysis and structural equation modeling were applied to explore the relationships among patients' stigma, self-efficacy, and cellular immunity and doctors' empathy abilities. RESULTS At the 2 time points, only the change in NK subset was statistically significant, while the changes in percentage of CD3+, CD4+, CD8+, and B cells were not statistically significant. The doctors' empathy abilities were negatively correlated with patients' stigma and were positively related to patients' self-efficacy. Patients' stigma was negatively related to NK subset, while self-efficacy was positively associated with NK subset. Patients' stigma and self-efficacy played a mediating role in the relationship between doctors' empathy abilities and patients' NK subset, and stigma had a stronger effect than self-efficacy. CONCLUSIONS Doctors' empathy abilities affected breast cancer patients' NK subset through their stigma and self-efficacy. The mental health of male breast cancer patients need more attention and empathy education needs to be improved.

Viral Immunotherapy to Eradicate Subclinical Brain Metastases

DTIC Science & Technology

2014-05-01

host innate and adaptive immune cells in metastases and normal tissues i. Months 6-21 ii. Basse Brain tissue with D2F2/E2 tumors from animals...and viral antigens which could activate memory T- cells in the draining lymphoid organs. Time course studies showed that virus infection produced a 2.6... lymphoid tissues. III. ACTIVATED NK CELLS LOCALIZE EFFICIENTLY AT TUMOR SITES The densities of NK cells found in well-established tumors in most

Stress and Immunity Breast Cancer Project

DTIC Science & Technology

1999-09-01

activity, stimulating the T cells with a monoclonal marker being studied: total T cells (CD3. fluorescein These findings suggest that how a person...sets of outcome P .006 .002 .002 .006 .012 .066 measures: 1) NK cell lysis at five E:T ratios. 2) response of NK cells to rIFN -y and rIL-2 stimulation ...the CES-D is relatively unaffected by physical symptoms and is, therefore, commonly used in research with medical patients5 0. Internal consistency

Dose intensification of TRAIL-inducing ONC201 inhibits metastasis and promotes intratumoral NK cell recruitment.

PubMed

Wagner, Jessica; Kline, C Leah; Zhou, Lanlan; Campbell, Kerry S; MacFarlane, Alexander W; Olszanski, Anthony J; Cai, Kathy Q; Hensley, Harvey H; Ross, Eric A; Ralff, Marie D; Zloza, Andrew; Chesson, Charles B; Newman, Jenna H; Kaufman, Howard; Bertino, Joseph; Stein, Mark; El-Deiry, Wafik S

2018-06-01

ONC201 is a first-in-class, orally active antitumor agent that upregulates cytotoxic TRAIL pathway signaling in cancer cells. ONC201 has demonstrated safety and preliminary efficacy in a first-in-human trial in which patients were dosed every 3 weeks. We hypothesized that dose intensification of ONC201 may impact antitumor efficacy. We discovered that ONC201 exerts dose- and schedule-dependent effects on tumor progression and cell death signaling in vivo. With dose intensification, we note a potent anti-metastasis effect and inhibition of cancer cell migration and invasion. Our preclinical results prompted a change in ONC201 dosing in all open clinical trials. We observed accumulation of activated NK+ and CD3+ cells within ONC201-treated tumors and that NK cell depletion inhibits ONC201 efficacy in vivo, including against TRAIL/ONC201-resistant Bax-/- tumors. Immunocompetent NCR1-GFP mice, in which NK cells express GFP, demonstrated GFP+ NK cell infiltration of syngeneic MC38 colorectal tumors. Activation of primary human NK cells and increased degranulation occurred in response to ONC201. Coculture experiments identified a role for TRAIL in human NK-mediated antitumor cytotoxicity. Preclinical results indicate the potential utility for ONC201 plus anti-PD-1 therapy. We observed an increase in activated TRAIL-secreting NK cells in the peripheral blood of patients after ONC201 treatment. The results offer what we believe to be a unique pathway of immune stimulation for cancer therapy.

Imaging burst kinetics and spatial coordination during serial killing by single natural killer cells

PubMed Central

Choi, Paul J.; Mitchison, Timothy J.

2013-01-01

Cytotoxic lymphocytes eliminate virus-infected and cancerous cells by immune recognition and killing through the perforin-granzyme pathway. Traditional killing assays measure average target cell lysis at fixed times and high effector:target ratios. Such assays obscure kinetic details that might reveal novel physiology. We engineered target cells to report on granzyme activity, used very low effector:target ratios to observe potential serial killing, and performed low magnification time-lapse imaging to reveal time-dependent statistics of natural killer (NK) killing at the single-cell level. Most kills occurred during serial killing, and a single NK cell killed up to 10 targets over a 6-h assay. The first kill was slower than subsequent kills, especially on poor targets, or when NK signaling pathways were partially inhibited. Spatial analysis showed that sequential kills were usually adjacent. We propose that NK cells integrate signals from the previous and current target, possibly by simultaneous contact. The resulting burst kinetics and spatial coordination may control the activity of NK cells in tissues. PMID:23576740

Activation of natural killer cells by hepatitis C virus particles in vitro.

PubMed

Farag, M M S; Weigand, K; Encke, J; Momburg, F

2011-09-01

Little is known about the ability of hepatitis C virus (HCV) to alter early innate immune responses in infected patients. Previous studies have shown that natural killer (NK) cells are functionally impaired after interaction of recombinant HCV glycoprotein E2 with the co-stimulatory CD81 molecule in vitro; however, the functional consequences of a prolonged contact of NK cells with HCV particles have remained unclear. We have examined the phenotypes of purified, interleukin-2-activated NK cells from healthy donors and HCV genotype 1b patients after culture for 5 days with HCV pseudoparticles (HCVpp) and serum samples containing HCV genotype 1b. NK cells from healthy donors and chronic HCV patients were found to up-regulate receptors associated with activation (NKp46, NKp44, NKp30, NKG2D), while NK receptors from the killer cell immunoglobulin-like receptor family (KIR/CD158), predominantly having an inhibitory function, were significantly down-modulated after culture in the presence of HCV particles compared with control cultures of NK cells. HCV-infected sera and HCVpp elicited significantly higher secretion of the NK effector lymphokines interferon-γ and tumour necrosis factor-α. Furthermore, HCV stimulated the cytotoxic potential of NK cells from normal donors and patients. The enhanced activation of NK cells after prolonged culture with HCVpp or HCV-containing sera for 5 days suggests that these innate effector cells may play an important role in viral control during early phases of HCV infection. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.

Tetraspecific scFv construct provides NK cell mediated ADCC and self-sustaining stimuli via insertion of IL-15 as a cross-linker

PubMed Central

Schmohl, Joerg U.; Felices, Martin; Todhunter, Deborah; Taras, Elizabeth; Miller, Jeffrey S.; Vallera, Daniel A.

2016-01-01

Background The design of a highly effective anti-cancer immune-engager would include targeting of highly drug refractory cancer stem cells (CSC). The design would promote effective antibody-dependent cell-mediated cytotoxicity (ADCC) and simultaneously promote costimulation to expand and self-sustain the effector NK cell population. Based on our bispecific NK cell engager platform we constructed a tetraspecific killer engager (TetraKE) comprising single-chain variable fragments (scFvs) binding FcγRIII (CD16) on NK cells, EpCAM on carcinoma cells and CD133 on cancer stem cells in order to promote ADCC. Furthermore, an Interleukin (IL)-15-crosslinker enhanced NK cell related proliferation resulting in a highly active drug termed 1615EpCAM133. Results Proliferation assays showed TetraKE promoted proliferation and enhanced NK cell survival. Drug-target binding, NK cell related degranulation, and IFN-γ production was specific for both tumor related antigens in EpCAM and CD133 bearing cancer cell lines. The TetraKE showed higher killing activity and superior dose dependent degranulation. Cytokine profiling showed a moderately enhanced IFN-γ production, enhanced GM-CSF production, but no evidence of induction of excessive cytokine release. Methods Assembly and synthesis of hybrid genes encoding the TetraKE were performed using DNA shuffling and ligation. The TetraKE was tested for efficacy, specificity, proliferation, survival, and cytokine production using carcinoma cell lines and functional assays measuring NK cell activity. Conclusion 1615EpCAM133 combines improved induction of ADCC with enhanced proliferation, limited cytokine response, and prolonged survival and proliferation of NK cells. By linking scFv-related targeting of carcinoma and CSCs with a sustaining IL-15 signal, our new construct shows great promise to target cancer and CSCs. PMID:27650544

Induction of Cell Cycle and NK Cell Responses by Live-Attenuated Oral Vaccines against Typhoid Fever

PubMed Central

Blohmke, Christoph J.; Hill, Jennifer; Darton, Thomas C.; Carvalho-Burger, Matheus; Eustace, Andrew; Jones, Claire; Schreiber, Fernanda; Goodier, Martin R.; Dougan, Gordon; Nakaya, Helder I.; Pollard, Andrew J.

2017-01-01

The mechanisms by which oral, live-attenuated vaccines protect against typhoid fever are poorly understood. Here, we analyze transcriptional responses after vaccination with Ty21a or vaccine candidate, M01ZH09. Alterations in response profiles were related to vaccine-induced immune responses and subsequent outcome after wild-type Salmonella Typhi challenge. Despite broad genetic similarity, we detected differences in transcriptional responses to each vaccine. Seven days after M01ZH09 vaccination, marked cell cycle activation was identified and associated with humoral immunogenicity. By contrast, vaccination with Ty21a was associated with NK cell activity and validated in peripheral blood mononuclear cell stimulation assays confirming superior induction of an NK cell response. Moreover, transcriptional signatures of amino acid metabolism in Ty21a recipients were associated with protection against infection, including increased incubation time and decreased severity. Our data provide detailed insight into molecular immune responses to typhoid vaccines, which could aid the rational design of improved oral, live-attenuated vaccines against enteric pathogens. PMID:29075261

Immunolocalization of Substance P and NK-1 Receptor in ADIPOSE Stem Cells.

PubMed

Muñoz, Miguel; Muñoz, Mario F; Ayala, Antonio

2017-12-01

Substance P (SP) is a neuropeptide belonging to the thachykinin peptide family. SP, after binding to its receptor, the neurokinin 1 receptor (NK1R), controls several transcription factors such as NF-κB, hypoxia inducible factor (HIF-1α), c-myc, c-fos, c-jun, and AP-1. SP and NK1R have a widespread distribution in both the central and peripheral nervous systems. They are also present in cells not belonging to the nervous system (immune cells, placenta, etc.). SP is located in all body fluids, that is, blood, cerebrospinal fluid, etc., making it ubiquitous throughout the human body. SP and NK1R genes are expressed in the stem cell line TF-1 and in primary stem cells derived from human placental cord blood. However, to our knowledge, the presence of SP and the NK1R receptor in adipose stem cells (ADSC) is unknown. We demonstrated by immunofluorescence the localization of SP and NK1R in human and rat ADSC. SP and NK1R are located in both the cytoplasm and the nucleus of these cells. The NK1R is higher in the nucleus than in the cytoplasm of ADSCs. By Western blot we demonstrated the presence of different isoforms of NK1R that have different subcellular locations in the ADSC. SP induces proliferation and mitogenesis through NK1R in ADSCs. These findings reported here for the first time suggest an important role for a SP/NK1R system, either as genetic and/or epigenetic factor, in both the cytoplasm and nucleus functions of the ADSCs. J. Cell. Biochem. 118: 4686-4696, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

An Improved Flow Cytometry Method For Precise Quantitation Of Natural-Killer Cell Activity

NASA Technical Reports Server (NTRS)

Crucian, Brian; Nehlsen-Cannarella, Sandra; Sams, Clarence

2006-01-01

The ability to assess NK cell cytotoxicity using flow cytometry has been previously described and can serve as a powerful tool to evaluate effector immune function in the clinical setting. Previous methods used membrane permeable dyes to identify target cells. The use of these dyes requires great care to achieve optimal staining and results in a broad spectral emission that can make multicolor cytometry difficult. Previous methods have also used negative staining (the elimination of target cells) to identify effector cells. This makes a precise quantitation of effector NK cells impossible due to the interfering presence of T and B lymphocytes, and the data highly subjective to the variable levels of NK cells normally found in human peripheral blood. In this study an improved version of the standard flow cytometry assay for NK activity is described that has several advantages of previous methods. Fluorescent antibody staining (CD45FITC) is used to positively identify target cells in place of membranepermeable dyes. Fluorescent antibody staining of target cells is less labor intensive and more easily reproducible than membrane dyes. NK cells (true effector lymphocytes) are also positively identified by fluorescent antibody staining (CD56PE) allowing a simultaneous absolute count assessment of both NK cells and target cells. Dead cells are identified by membrane disruption using the DNA intercalating dye PI. Using this method, an exact NK:target ratio may be determined for each assessment, including quantitation of NK target complexes. Backimmunoscatter gating may be used to track live vs. dead Target cells via scatter properties. If desired, NK activity may then be normalized to standardized ratios for clinical comparisons between patients, making the determination of PBMC counts or NK cell percentages prior to testing unnecessary. This method provides an exact cytometric determination of NK activity that highly reproducible and may be suitable for routine use in the clinical setting.

Natural Killer Cell Activity and Interleukin-12 in Metabolically Healthy versus Metabolically Unhealthy Overweight Individuals

PubMed Central

Kim, Minjoo; Kim, Minkyung; Yoo, Hye Jin; Lee, Jong Ho

2017-01-01

The purpose of this study was to determine whether the immune system is involved in the different metabolic circumstances in healthy and unhealthy overweight individuals. We examined the metabolic and immune characteristics of 117 overweight individuals. Subjects were classified as metabolically healthy overweight (MHO, n = 72) or metabolically unhealthy overweight (MUO, n = 45). The immune response was measured by circulating levels of natural killer (NK) cell activity and cytokines. Both groups were comparable with regards to age, sex distribution, smoking and drinking status, and body mass index. When compared to the MHO group, the MUO group showed higher systolic and diastolic blood pressure, serum levels of triglyceride, glucose, glucose-related markers, and lower levels of HDL cholesterol. Compared to the MHO group, the MUO group showed 39% lower interferon-γ levels (not significant) and 41% lower interleukin (IL)-12 levels (significant). The MUO group also showed lower NK cell activity at E:T ratios of 10:1, 5:1, 2.5:1, and 1.25:1 (all Ps < 0.05) than the MHO group. This study indicates that individuals displaying the MUO phenotype present an unfavorable immune system with lower NK cell activities under all assay conditions and lower serum levels of IL-12 than the activities and levels in similarly overweight MHO individuals. This result suggests that the immune system may be altered in overweight individuals who are at risk for overweight/obesity-related comorbidities. PMID:29238351

Vaccinating for natural killer cell effector functions.

PubMed

Wagstaffe, Helen R; Mooney, Jason P; Riley, Eleanor M; Goodier, Martin R

2018-01-01

Vaccination has proved to be highly effective in reducing global mortality and eliminating infectious diseases. Building on this success will depend on the development of new and improved vaccines, new methods to determine efficacy and optimum dosing and new or refined adjuvant systems. NK cells are innate lymphoid cells that respond rapidly during primary infection but also have adaptive characteristics enabling them to integrate innate and acquired immune responses. NK cells are activated after vaccination against pathogens including influenza, yellow fever and tuberculosis, and their subsequent maturation, proliferation and effector function is dependent on myeloid accessory cell-derived cytokines such as IL-12, IL-18 and type I interferons. Activation of antigen-presenting cells by live attenuated or whole inactivated vaccines, or by the use of adjuvants, leads to enhanced and sustained NK cell activity, which in turn contributes to T cell recruitment and memory cell formation. This review explores the role of cytokine-activated NK cells as vaccine-induced effector cells and in recall responses and their potential contribution to vaccine and adjuvant development.

Red ginseng and vitamin C increase immune cell activity and decrease lung inflammation induced by influenza A virus/H1N1 infection.

PubMed

Kim, Hyemin; Jang, Mirim; Kim, Yejin; Choi, Jiyea; Jeon, Jane; Kim, Jihoon; Hwang, Young-Il; Kang, Jae Seung; Lee, Wang Jae

2016-03-01

Because red ginseng and vitamin C have immunomodulatory function and anti-viral effect, we investigated whether red ginseng and vitamin C synergistically regulate immune cell function and suppress viral infection. Red ginseng and vitamin C were treated to human peripheral blood mononuclear cells (PBMCs) or sarcoma-associated herpesvirus (KSHV)-infected BCBL-1, and administrated to Gulo(-/-) mice, which are incapable of synthesizing vitamin C, with or without influenza A virus/H1N1 infection. Red ginseng and vitamin C increased the expression of CD25 and CD69 of PBMCs and natural killer (NK) cells. Co-treatment of them decreased cell viability and lytic gene expression in BCBL-1. In Gulo(-/-) mice, red ginseng and vitamin C increased the expression of NKp46, a natural cytotoxic receptor of NK cells and interferon (IFN)-γ production. Influenza infection decreased the survival rate, and increased inflammation and viral plaque accumulation in the lungs of vitamin C-depleted Gulo(-/-) mice, which were remarkably reduced by red ginseng and vitamin C supplementation. Administration of red ginseng and vitamin C enhanced the activation of immune cells like T and NK cells, and repressed the progress of viral lytic cycle. It also reduced lung inflammation caused by viral infection, which consequently increased the survival rate. © 2016 Royal Pharmaceutical Society, Journal of Pharmacy and Pharmacology.

Prevention of psychological stress-induced immune suppression by aged garlic extract.

PubMed

Kyo, E; Uda, N; Ushijima, M; Kasuga, S; Itakura, Y

1999-11-01

We determined the effect of Aged Garlic Extract (AGE) on damage caused to immune function by a psychological stress using a communication box. After four days of a psychological stress, a decrease in spleen weight and spleen cells was observed in the psychological stress-exposed mice as compared normal mice (non-stress). AGE significantly prevented the decreases in spleen weight and cells. Additionally, AGE significantly prevented the reduction of hemolytic plaque-forming-cells in spleen cells and anti-SRBC antibody titer in serum caused by this psychological stress. Moreover, a reduction in NK activities was observed in the psychological stress-exposed mice as compared with normal mice (non-stress), whereas NK activities in the AGE administered mice were almost the same as normal mice (non-stress). These results indicate that psychological stress qualitatively and quantitatively impairs immune function, and that AGE is extremely useful for preventing psychologically-induced damage.

Effects of fatigue on immune function in nurses performing shift work.

PubMed

Nagai, Makie; Morikawa, Yuko; Kitaoka, Kazuyo; Nakamura, Koshi; Sakurai, Masaru; Nishijo, Muneko; Hamazaki, Yuko; Maruzeni, Shoko; Nakagawa, Hideaki

2011-01-01

We investigated the effects of fatigue on NK cell function and lymphocyte subpopulations in nurses performing shift work using a longitudinal design. Fifty-seven female nurses engaged in shift work at a hospital in Japan were selected for our study cohort. The hospital used a counterclockwise rotating three-shift system. Night shifts followed day shifts after a seven-hour interval. Immune parameters measured at the beginning of the day shift through to the end of the night shift were compared between two groups stratified by their level of fatigue. Statistical differences were evaluated after adjusting for baseline immune values and other demographic features. Subjective feelings of fatigue increased progressively from the beginning of day shifts to the end of night shifts. From the beginning of day shifts to the end of night shifts, NK cell activity and CD16(+)CD56(+) lymphocytes decreased, while CD3(+) and CD4(+) lymphocytes increased. The group with the greater increase in fatigue showed a larger decrease in NK cell activity and a larger increase in CD4(+)lymphocytes when compared with the group reporting less fatigue. These findings did not change after adjusting for demographic factors and sleep hours. Our data suggest that shift work has deleterious effects on NK cell function and that the effects depend on the degree of fatigue. Proper management of shift work may lessen fatigue in workers and also ameliorate many health problems experienced by shift workers.

Gene delivery of TIPE2 inhibits breast cancer development and metastasis via CD8+ T and NK cell-mediated antitumor responses.

PubMed

Zhang, Zhenhua; Liu, Li; Cao, Shousong; Zhu, Yizhun; Mei, Qibing

2017-05-01

Breast cancer is the second leading cause of cancer-related deaths in the female patients which was mainly caused by metastasis. Development of target gene therapy for breast cancer to suppress tumor progress and metastasis will improve the therapeutic options and be of great benefit to the patients. Tumor necrosis factor-alpha-induced protein 8-like 2 is a novel molecule for maintaining immune homeostasis and is involved in cancer development. In the present study, we overexpressed TIPE2 in breast cancer cells to investigate the role of TIPE2 in the development of breast cancer. Our results showed that overexpression of TIPE2 significantly inhibited the proliferation of 4T1 cells in vitro and in vivo. We constructed a non-viral targeted gene therapeutic system by using the minicircle plasmids expressing TIPE2. We found that the growth and metastasis of breast cancer was significantly inhibited by hydrodynamic gene delivery of TIPE2 plasmids in vivo. Mechanistically, TIPE2 increased T and NK cells, and decreased MDSCs. Gene delivery of TIPE2 up-regulated the production of IFN-γ and TNF-α by CD8 + T and NK cells in spleens and tumor microenvironment, and enhanced the cytotoxic activity of CD8 + T and NK cells. Taken together, TIPE2 inhibited breast cancer development and metastasis possibly via promoting CD8 + T and NK cell-mediated antitumor immune responses. Thus, the results indicate that TIPE2 may be a potential therapeutic target for breast cancer therapy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Host protective ASP-based vaccine against the parasitic nematode Ostertagia ostertagi triggers NK cell activation and mixed IgG1-IgG2 response.

PubMed

González-Hernández, Ana; Van Coppernolle, Stefanie; Borloo, Jimmy; Van Meulder, Frederik; Paerewijck, Oonagh; Peelaers, Iris; Leclercq, Georges; Claerebout, Edwin; Geldhof, Peter

2016-07-11

The mucus-dwelling parasite Ostertagia ostertagi is one of the most important gastrointestinal nematodes in cattle. Our group has previously demonstrated the protective capacity of a vaccine against this parasite based on a native activation-associated secreted protein ASP1 (nASP) in combination with the saponin adjuvant QuilA. The aim of the current study was to analyse the effect of both antigen and adjuvant on the cellular and humoral vaccine-induced immune responses by comparing the native ASP to a recombinant version expressed in Pichia pastoris (pASP) and replacing QuilA by Al(OH)3. Immunization of cattle with the protective nASP+QuilA vaccine was associated with antigen-induced proliferation of natural killer (NK) cells combined with IFN-γ secretion and the induction of a mixed IgG1/IgG2 antibody response. ASP-specific activation and proliferation of NK cells was also observed in mice following the same vaccination regime. Replacing QuilA by Al(OH)3 or nASP by pASP significantly decreased the capacity of the vaccines to trigger both NK cell activation and antibody responses and failed to induce protection against a challenge infection. Reduction of the structurally anchoring disulphide bonds of the nASP completely abolished its ability to induce NK cell activation and antibody responses, highlighting the importance of protein conformation for the immunostimulatory activity.

Increased CD56(bright) NK cells in HIV-HCV co-infection and HCV mono-infection are associated with distinctive alterations of their phenotype.

PubMed

Bhardwaj, Suvercha; Ahmad, Fareed; Wedemeyer, Heiner; Cornberg, Marcus; Schulze Zur Wiesch, Julian; van Lunzen, Jan; Sarin, Shiv K; Schmidt, Reinhold E; Meyer-Olson, Dirk

2016-04-18

HIV-HCV co-infection is associated with accelerated progression to hepatic fibrosis, cirrhosis and hepatocellular carcinoma than HCV mono-infection. The contribution of innate immunity during HIV-HCV co-infection has been a relatively under-investigated area. Natural killer (NK) cells are pivotal sentinels of innate immunity against viruses and tumour cells. In this study we evaluated the effect of HIV-HCV co-infection on peripheral blood NK cell subsets with emphasis on the phenotype of CD56(bright) NK cells. Sixty patients were included in the study; HIV mono-infected (n = 12), HCV mono-infected (n = 15), HCV-HIV co-infected (n = 21) and healthy controls (n = 16). PBMCs were isolated and immunophenotyping of NK cells was performed by flowcytometry. We observed an expansion of CD56(bright) NK cell subset in HIV-HCV co-infection as compared to healthy controls and HIV mono-infected group. All the infected groups had an upregulated expression of the activating receptor NKG2D on CD56(bright) NK cells in comparison to healthy controls while not differing amongst themselves. The expression of NKp46 in HIV-HCV co-infected group was significantly upregulated as compared to both HIV as well as HCV mono-infections while NKp30 expression in the HIV-HCV co-infected group significantly differed as compared to HIV mono-infection. The CD56(bright) NK cell subset was activated in HIV-HCV co-infection as assessed by the expression of CD69 as compared to healthy controls but was significantly downregulated in comparison to HIV mono-infection. CD95 expression on CD56(bright) NK cells followed the same pattern where there was an increased expression of CD95 in HIV mono-infection and HIV-HCV co-infection as compared to healthy controls. In contrast to CD69 expression, CD95 expression in HCV mono-infection was decreased when compared to HIV mono-infection and HIV-HCV co-infection. Finally, expression of CXCR3 on CD56(bright) NK cells was increased in HIV-HCV co-infection in comparison to HIV mono-infection while remaining similar to HCV mono-infection. Thus, HIV-HCV co-infection is able to modulate the phenotype of CD56(bright) NK cell subset in a unique way such that NKp46 and CXCR3 expressions are distinct for co-infection while both mono-infections have an additive effect on CD56(bright), CD69 with CD95 expressions. HCV mono-infection has a dominant effect on NKp30 expression while NKG2D and CD127 expressions remained same in all the groups.

Isotype Diversification of IgG Antibodies to HIV Gag Proteins as a Therapeutic Vaccination Strategy for HIV Infection

PubMed Central

French, Martyn A.; Abudulai, Laila N.; Fernandez, Sonia

2013-01-01

The development of vaccines to treat and prevent human immunodeficiency virus (HIV) infection has been hampered by an incomplete understanding of “protective” immune responses against HIV. Natural control of HIV-1 infection is associated with T-cell responses against HIV-1 Gag proteins, particularly CD8+ T-cell responses restricted by “protective” HLA-B alleles, but other immune responses also contribute to immune control. These immune responses appear to include IgG antibodies to HIV-1 Gag proteins, interferon-α-dependant natural killer (NK) cell responses and plasmacytoid dendritic cell (pDC) responses. Here, it is proposed that isotype diversification of IgG antibodies against HIV-1 Gag proteins, to include IgG2, as well as IgG3 and IgG1 antibodies, will broaden the function of the antibody response and facilitate accessory cell responses against HIV-1 by NK cells and pDCs. We suggest that this should be investigated as a vaccination strategy for HIV-1 infection. PMID:26344116

Generation of recombinant canine interleukin-15 and evaluation of its effects on the proliferation and function of canine NK cells.

PubMed

Lee, Soo-Hyeon; Shin, Dong-Jun; Kim, Sang-Ki

2015-05-15

Interleukin-15 (IL-15) is a pleiotropic cytokine that plays a pivotal role in both innate and adaptive immunity. IL-15 is also a promising cytokine for treating cancer. Despite the growing importance of the clinical use of IL-15 for immunotherapy, no attempts have been made to generate a recombinant canine IL-15 (rcIL-15) and to examine its effects on the antitumor activities of immune effector cells in dogs. Here, we generated an rcIL-15 protein consisting of Asn-49-Ser-162 with a C-terminal His tag and examined its functions ex vivo in terms of the proliferation and antitumor effects on canine non-B, non-T, large granular natural killer (NK) cells. Non-B, non-T, large granular NK cells rapidly expanded in response to stimulation with rcIL-15 in the presence of IL-2, and a majority of the cells that selectively expanded over 21 days exhibited a CD3(-)CD5(-)CD4(-)CD8(+/-)CD21(-) phenotype. Purified rcIL-15 significantly enhanced the expansion rate of canine NK cells derived from peripheral blood mononuclear cells compared to human IL-15, or culture in the absence of IL-15 for 21 days (p<0.05). Purified rcIL-15 was superior at enhancing the effector function of NK cells compared to human IL-15. The cytotoxic activity against canine thyroid adenocarcinoma (CTAC) cells, interferon-γ production, and the mRNA expression levels of perforin and granzyme B of expanded NK cells cultured with rcIL-15 were significantly elevated compared to those cultured with human IL-15 or without IL-15 (p<0.05). Intravenous administration of rcIL-15 significantly increased the numbers of lymphocytes in the peripheral blood of dogs on days 6, 8, and 11 after injection compared to numbers before administration (p<0.05). The results of this study suggest that the rcIL-15 protein, consisting of Asn-49-Ser-162, enhanced the proliferation and antitumor effects of canine NK cells and promoted the generation of lymphocytes in dogs. Copyright © 2015 Elsevier B.V. All rights reserved.

Human embryonic stem cell-derived NK cells acquire functional receptors and cytolytic activity.

PubMed

Woll, Petter S; Martin, Colin H; Miller, Jeffrey S; Kaufman, Dan S

2005-10-15

Human embryonic stem cells (hESCs) provide a unique resource to analyze early stages of human hematopoiesis. However, little is known about the ability to use hESCs to evaluate lymphocyte development. In the present study, we use a two-step culture method to demonstrate efficient generation of functional NK cells from hESCs. The CD56(+)CD45(+) hESC-derived lymphocytes express inhibitory and activating receptors typical of mature NK cells, including killer cell Ig-like receptors, natural cytotoxicity receptors, and CD16. Limiting dilution analysis suggests that these cells can be produced from hESC-derived hemopoietic progenitors at a clonal frequency similar to CD34(+) cells isolated from cord blood. The hESC-derived NK cells acquire the ability to lyse human tumor cells by both direct cell-mediated cytotoxicity and Ab-dependent cellular cytotoxicity. Additionally, activated hESC-derived NK cells up-regulate cytokine production. hESC-derived lymphoid progenitors provide a novel means to characterize specific cellular and molecular mechanisms that lead to development of specific human lymphocyte populations. These cells may also provide a source for innovative cellular immune therapies.

A decrease of regulatory T cells and altered expression of NK receptors are observed in subacute sclerosing panencephalitis.

PubMed

Yentur, Sibel P; Gurses, Candan; Demirbilek, Veysi; Adin-Cinar, Suzan; Kuru, Umit; Uysal, Serap; Yapici, Zuhal; Yilmaz, Gülden; Cokar, Ozlem; Onal, Emel; Gökyigit, Aysen; Saruhan-Direskeneli, Güher

2014-12-01

Subacute sclerosing panencephalitis (SSPE) is caused by a persistent measles virus infection. Regulatory mechanisms can be responsible for a failure of immunosurveillance in children with SSPE. In this study, peripheral blood cells of 71 patients with SSPE and 57 children with other diseases were compared phenotypically. The proportions of CD4(+), CD8(+) T, and NK cells were homogenous, whereas total CD3(+) T and Treg (CD4(+)CD25(+)CD152(+)) cells were decreased in patients with SSPE. The proportion of CD8(+) T cells expressing the inhibitory NKG2A(+) receptor was also decreased (1.7% ± 1.7% vs. 2.6% ± 1.9%, p = 0.007) in patients with SSPE, whereas the proportion of NK cells expressing activating NKG2C was increased compared with the control group (30.0% ± 17.3% vs. 22.2% ± 17.0%, p = 0.039). The decrease in the number of cells with regulatory phenotype, the lower presence of the inhibitory NK receptors on CD8(+) cells, and higher activating NK receptors on NK cells in SSPE indicate an upregulation of these cell types that favors their response. This state of active immune response may be caused by chronic stimulation of viral antigens leading to altered regulatory pathways.

Nasal Acai polysaccharides potentiate innate immunity to protect against pulmonary Francisella tularensis and Burkholderia pseudomallei Infections.

PubMed

Skyberg, Jerod A; Rollins, MaryClare F; Holderness, Jeff S; Marlenee, Nicole L; Schepetkin, Igor A; Goodyear, Andrew; Dow, Steven W; Jutila, Mark A; Pascual, David W

2012-01-01

Pulmonary Francisella tularensis and Burkholderia pseudomallei infections are highly lethal in untreated patients, and current antibiotic regimens are not always effective. Activating the innate immune system provides an alternative means of treating infection and can also complement antibiotic therapies. Several natural agonists were screened for their ability to enhance host resistance to infection, and polysaccharides derived from the Acai berry (Acai PS) were found to have potent abilities as an immunotherapeutic to treat F. tularensis and B. pseudomallei infections. In vitro, Acai PS impaired replication of Francisella in primary human macrophages co-cultured with autologous NK cells via augmentation of NK cell IFN-γ. Furthermore, Acai PS administered nasally before or after infection protected mice against type A F. tularensis aerosol challenge with survival rates up to 80%, and protection was still observed, albeit reduced, when mice were treated two days post-infection. Nasal Acai PS administration augmented intracellular expression of IFN-γ by NK cells in the lungs of F. tularensis-infected mice, and neutralization of IFN-γ ablated the protective effect of Acai PS. Likewise, nasal Acai PS treatment conferred protection against pulmonary infection with B. pseudomallei strain 1026b. Acai PS dramatically reduced the replication of B. pseudomallei in the lung and blocked bacterial dissemination to the spleen and liver. Nasal administration of Acai PS enhanced IFN-γ responses by NK and γδ T cells in the lungs, while neutralization of IFN-γ totally abrogated the protective effect of Acai PS against pulmonary B. pseudomallei infection. Collectively, these results demonstrate Acai PS is a potent innate immune agonist that can resolve F. tularensis and B. pseudomallei infections, suggesting this innate immune agonist has broad-spectrum activity against virulent intracellular pathogens.

Characterization of the myeloid-derived suppressor cell subset regulated by NK cells in malignant lymphoma.

PubMed

Sato, Yusuke; Shimizu, Kanako; Shinga, Jun; Hidaka, Michihiro; Kawano, Fumio; Kakimi, Kazuhiro; Yamasaki, Satoru; Asakura, Miki; Fujii, Shin-Ichiro

2015-03-01

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with the ability to suppress immune responses and are currently classified into three distinct MDSC subsets: monocytic, granulocytic and non-monocytic, and non-granulocytic MDSCs. Although NK cells provide an important first-line defense against newly transformed cancer cells, it is unknown whether NK cells can regulate MDSC populations in the context of cancer. In this study, we initially found that the frequency of MDSCs in non-Hodgkin lymphoma (NHL) patients was increased and inversely correlated with that of NK cells, but not that of T cells. To investigate the regulation of MDSC subsets by NK cells, we used an EL4 murine lymphoma model and found the non-monocytic and non-granulocytic MDSC subset, i.e., Gr1 + CD11b + Ly6G med Ly6C med MDSC, is increased after NK cell depletion. The MDSC population that expresses MHC class II, CD80, CD124, and CCR2 is regulated mainly by CD27 + CD11b + NK cells. In addition, this MDSC subset produces some immunosuppressive cytokines, including IL-10 but not nitric oxide (NO) or arginase. We also examined two subsets of MDSCs (CD14 + HLA-DR - and CD14 - HLA-DR - MDSC) in NHL patients and found that higher IL-10-producing CD14 + HLA-DR - MDSC subset can be seen in lymphoma patients with reduced NK cell frequency in peripheral blood. Our analyses of MDSCs in this study may enable a better understanding of how MDSCs manipulate the tumor microenvironment and are regulated by NK cells in patients with lymphoma.

Characterization of the myeloid-derived suppressor cell subset regulated by NK cells in malignant lymphoma

PubMed Central

Sato, Yusuke; Shimizu, Kanako; Shinga, Jun; Hidaka, Michihiro; Kawano, Fumio; Kakimi, Kazuhiro; Yamasaki, Satoru; Asakura, Miki; Fujii, Shin-ichiro

2015-01-01

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population with the ability to suppress immune responses and are currently classified into three distinct MDSC subsets: monocytic, granulocytic and non-monocytic, and non-granulocytic MDSCs. Although NK cells provide an important first-line defense against newly transformed cancer cells, it is unknown whether NK cells can regulate MDSC populations in the context of cancer. In this study, we initially found that the frequency of MDSCs in non-Hodgkin lymphoma (NHL) patients was increased and inversely correlated with that of NK cells, but not that of T cells. To investigate the regulation of MDSC subsets by NK cells, we used an EL4 murine lymphoma model and found the non-monocytic and non-granulocytic MDSC subset, i.e., Gr1+CD11b+Ly6GmedLy6Cmed MDSC, is increased after NK cell depletion. The MDSC population that expresses MHC class II, CD80, CD124, and CCR2 is regulated mainly by CD27+CD11b+NK cells. In addition, this MDSC subset produces some immunosuppressive cytokines, including IL-10 but not nitric oxide (NO) or arginase. We also examined two subsets of MDSCs (CD14+HLA-DR− and CD14− HLA-DR− MDSC) in NHL patients and found that higher IL-10-producing CD14+HLA-DR−MDSC subset can be seen in lymphoma patients with reduced NK cell frequency in peripheral blood. Our analyses of MDSCs in this study may enable a better understanding of how MDSCs manipulate the tumor microenvironment and are regulated by NK cells in patients with lymphoma. PMID:25949922

Human natural killer cells prevent infectious mononucleosis features by targeting lytic Epstein-Barr virus infection.

PubMed

Chijioke, Obinna; Müller, Anne; Feederle, Regina; Barros, Mario Henrique M; Krieg, Carsten; Emmel, Vanessa; Marcenaro, Emanuela; Leung, Carol S; Antsiferova, Olga; Landtwing, Vanessa; Bossart, Walter; Moretta, Alessandro; Hassan, Rocio; Boyman, Onur; Niedobitek, Gerald; Delecluse, Henri-Jacques; Capaul, Riccarda; Münz, Christian

2013-12-26

Primary infection with the human oncogenic Epstein-Barr virus (EBV) can result in infectious mononucleosis (IM), a self-limiting disease caused by massive lymphocyte expansion that predisposes for the development of distinct EBV-associated lymphomas. Why some individuals experience this symptomatic primary EBV infection, whereas the majority acquires the virus asymptomatically, remains unclear. Using a mouse model with reconstituted human immune system components, we show that depletion of human natural killer (NK) cells enhances IM symptoms and promotes EBV-associated tumorigenesis mainly because of a loss of immune control over lytic EBV infection. These data suggest that failure of innate immune control by human NK cells augments symptomatic lytic EBV infection, which drives lymphocyte expansion and predisposes for EBV-associated malignancies. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

Frontline Science: Defects in immune function in patients with sepsis are associated with PD-1 or PD-L1 expression and can be restored by antibodies targeting PD-1 or PD-L1

PubMed Central

Patera, Andriani C.; Drewry, Anne M.; Chang, Katherine; Beiter, Evan R.; Osborne, Dale; Hotchkiss, Richard S.

2016-01-01

Sepsis is a heterogeneous syndrome comprising a highly diverse and dynamic mixture of hyperinflammatory and compensatory anti-inflammatory immune responses. This immune phenotypic diversity highlights the importance of proper patient selection for treatment with the immunomodulatory drugs that are entering clinical trials. To better understand the serial changes in immunity of critically ill patients and to evaluate the potential efficacy of blocking key inhibitory pathways in sepsis, we undertook a broad phenotypic and functional analysis of innate and acquired immunity in the same aliquot of blood from septic, critically ill nonseptic, and healthy donors. We also tested the ability of blocking the checkpoint inhibitors programmed death receptor-1 (PD-1) and its ligand (PD-L1) to restore the function of innate and acquired immune cells. Neutrophil and monocyte function (phagocytosis, CD163, cytokine expression) were progressively diminished as sepsis persisted. An increasing frequency in PD-L1+-suppressor phenotype neutrophils [low-density neutrophils (LDNs)] was also noted. PD-L1+ LDNs and defective neutrophil function correlated with disease severity, consistent with the potential importance of suppressive neutrophil populations in sepsis. Reduced neutrophil and monocyte function correlated both with their own PD-L1 expression and with PD-1 expression on CD8+ T cells and NK cells. Conversely, reduced CD8+ T cell and NK cell functions (IFN-γ production, granzyme B, and CD107a expression) correlated with elevated PD-L1+ LDNs. Importantly, addition of antibodies against PD-1 or PD-L1 restored function in neutrophil, monocyte, T cells, and NK cells, underlining the impact of the PD-1:PD-L1 axis in sepsis-immune suppression and the ability to treat multiple deficits with a single immunomodulatory agent. PMID:27671246

Modulation of Immune Cell Functions by the E3 Ligase Cbl-b

PubMed Central

Lutz-Nicoladoni, Christina; Wolf, Dominik; Sopper, Sieghart

2015-01-01

Maintenance of immunological tolerance is a critical hallmark of the immune system. Several signaling checkpoints necessary to balance activating and inhibitory input to immune cells have been described so far, among which the E3 ligase Cbl-b appears to be a central player. Cbl-b is expressed in all leukocyte subsets and regulates several signaling pathways in T cells, NK cells, B cells, and different types of myeloid cells. In most cases, Cbl-b negatively regulates activation signals through antigen or pattern recognition receptors and co-stimulatory molecules. In line with this function, cblb-deficient immune cells display lower activation thresholds and cblb knockout mice spontaneously develop autoimmunity and are highly susceptible to experimental autoimmunity. Interestingly, genetic association studies link CBLB-polymorphisms with autoimmunity also in humans. Vice versa, the increased activation potential of cblb-deficient cells renders them more potent to fight against malignancies or infections. Accordingly, several reports have shown that cblb knockout mice reject tumors, which mainly depends on cytotoxic T and NK cells. Thus, targeting Cbl-b may be an interesting strategy to enhance anti-cancer immunity. In this review, we summarize the findings on the molecular function of Cbl-b in different cell types and illustrate the potential of Cbl-b as target for immunomodulatory therapies. PMID:25815272

The natural product chitosan enhances the anti-tumor activity of natural killer cells by activating dendritic cells.

PubMed

Li, Xinxin; Dong, Wenjuan; Nalin, Ansel P; Wang, Yufeng; Pan, Pan; Xu, Bo; Zhang, Yibo; Tun, Steven; Zhang, Jianying; Wang, Li-Shu; He, Xiaoming; Caligiuri, Michael A; Yu, Jianhua

2018-01-01

Natural products comprise an important class of biologically active molecules. Many of these compounds derived from natural sources exhibit specific physiologic or biochemical effects. An example of a natural product is chitosan, which is enriched in the shells of certain seafood that are frequently consumed worldwide. Like other natural products, chitosan has the potential for applications in clinical medicine and perhaps in cancer therapy. Toward this end, the immunomodulatory or anti-cancer properties of chitosan have yet to be reported. In this study, we discovered that chitosan enhanced the anti-tumor activity of natural killer (NK) cells by activating dendritic cells (DCs). In the presence of DCs, chitosan augmented IFN-γ production by human NK cells. Mechanistically, chitosan activated DCs to express pro-inflammatory cytokines such as interleukin (IL)-12 and IL-15, which in turn activated the STAT4 and NF-κB signaling pathways, respectively, in NK cells. Moreover, chitosan promoted NK cell survival, and also enhanced NK cell cytotoxicity against leukemia cells. Finally, a related in vivo study demonstrated that chitosan activated NK cells against B16F10 tumor cells in an immunocompetent syngeneic murine melanoma model. This effect was accompanied by in vivo upregulation of IL-12 and IL-15 in DCs, as well as increased IFN-γ production and cytolytic degranulation in NK cells. Collectively, our results demonstrate that chitosan activates DCs leading to enhanced capacity for immune surveillance by NK cells. We believe that our study has future clinical applications for chitosan in the prevention or treatment of cancer and infectious diseases.

Exposures to the environmental toxicants pentachlorophenol (PCP) and dichlorodiphenyltrichloroethane (DDT) modify secretion of interleukin 1-beta (IL-1β) from human immune cells.

PubMed

Martin, Tamara J; Whalen, Margaret M

2017-04-01

Pentachlorophenol (PCP) and Dichlorodiphenyltrichloroethane (DDT) are environmental contaminants found in human blood. Previous studies have shown that PCP and DDT inhibit the lytic function of highly purified human natural killer (NK) lymphocytes and decrease the expression of several surface proteins on NK cells. Interleukin-1 βeta (IL-1β) is a cytokine produced by lymphocytes and monocytes, and anything that elevates its levels inappropriately can lead to chronic inflammation, which among other consequences can increase tumor development and invasiveness. Here, PCP and DDT were examined for their ability to alter secretion of IL-1β from immune cell preparations of various complexity: NK cells; monocyte-depleted (MD) peripheral blood mononuclear cells (PBMCS); and PBMCs. Cells were exposed to concentrations of PCP ranging from 5 to 0.05 µM and DDT concentrations of 2.5-0.025 μM for 24, 48 h, and 6 days. Results showed that both PCP and DDT increased IL-1β secretion from all of the immune cell preparations. The specific concentrations of PCP and DDT that increased IL-1β secretion varied by donor. Immune cells from all donors showed compound-induced increases in IL-1β secretion at one or more concentration at one or more length of exposure. The mechanism of PCP stimulation of IL1-β secretion was also addressed, and it appears that the MAPKs, ERK1/2 and p38, may be utilized by PCP to stimulate secretion of IL-1β.

The aryl hydrocarbon receptor is required for the maintenance of liver-resident natural killer cells

PubMed Central

2016-01-01

A tissue-resident population of natural killer cells (NK cells) in the liver has recently been described to have the unique capacity to confer immunological memory in the form of hapten-specific contact hypersensitivity independent of T and B cells. Factors regulating the development and maintenance of these liver-resident NK cells are poorly understood. The aryl hydrocarbon receptor (AhR) is a transcription factor modulated by exogenous and endogenous ligands that is important in the homeostasis of immune cells at barrier sites, such as the skin and gut. In this study, we show that liver-resident NK (NK1.1+CD3−) cells, defined as CD49a+TRAIL+CXCR6+DX5− cells in the mouse liver, constitutively express AhR. In AhR−/− mice, there is a significant reduction in the proportion and absolute number of these cells, which results from a cell-intrinsic dependence on AhR. This deficiency in liver-resident NK cells appears to be the result of higher turnover and increased susceptibility to cytokine-induced cell death. Finally, we show that this deficiency has functional implications in vivo. Upon hapten exposure, AhR−/− mice are not able to mount an NK cell memory response to hapten rechallenge. Together, these data demonstrate the requirement of AhR for the maintenance of CD49a+TRAIL+CXCR6+DX5− liver-resident NK cells and their hapten memory function. PMID:27670593

Unconventional repertoire profile is imprinted during acute chikungunya infection for natural killer cells polarization toward cytotoxicity.

PubMed

Petitdemange, Caroline; Becquart, Pierre; Wauquier, Nadia; Béziat, Vivien; Debré, Patrice; Leroy, Eric M; Vieillard, Vincent

2011-09-01

Chikungunya virus (CHIKV) is a worldwide emerging pathogen. In humans it causes a syndrome characterized by high fever, polyarthritis, and in some cases lethal encephalitis. Growing evidence indicates that the innate immune response plays a role in controlling CHIKV infection. We show here that CHIKV induces major but transient modifications in NK-cell phenotype and function soon after the onset of acute infection. We report a transient clonal expansion of NK cells that coexpress CD94/NKG2C and inhibitory receptors for HLA-C1 alleles and are correlated with the viral load. Functional tests reveal cytolytic capacity driven by NK cells in the absence of exogenous signals and severely impaired IFN-γ production. Collectively these data provide insight into the role of this unique subset of NK cells in controlling CHIKV infection by subset-specific expansion in response to acute infection, followed by a contraction phase after viral clearance.

Activation of innate immunity by prostate specific antigen (PSA).

PubMed

Kodak, James A; Mann, Dean L; Klyushnenkova, Elena N; Alexander, Richard B

2006-11-01

Prostate specific antigen (PSA) is a serine protease secreted by the prostatic epithelium. The only known function of the protein is to cleave seminogelin. We wished to determine if PSA activated peripheral blood mononuclear cells (PBMC). PBMC and selected sub-populations were cultured with purified PSA. Secretion of IFNgamma was measured by cytokine capture flow cytometry and enzyme-linked immunosorbent assay. We observed secretion of IFNgamma and a proliferative response in PBMC cultured with PSA. We found that NK cells were the source of the IFNgamma but NK cells were not directly stimulated by PSA. Rather, a soluble factor secreted primarily by CD14 monocytes in response to PSA stimulated NK cells to secrete IFNgamma. PSA induces a pro-inflammatory response that results in the secretion of INFgamma by NK cells. The presence of large amounts of PSA could contribute to the common finding of inflammatory infiltrates in the prostate.

Increase of CD69, CD161 and CD94 on NK cells in women with recurrent spontaneous abortion and in vitro fertilization failure.

PubMed

Ghafourian, Mehri; Karami, Najmeh; Khodadadi, Ali; Nikbakht, Roshan

2014-06-01

Recurrent spontaneous abortion (RSA) and in vitro fertilization (IVF) failure with unknown causes are the controversial issues that are probably related to the immune system. To compare circulating NK cells expressing activation and inhibition surface markers between patients with RSA and IVF failure with those of healthy multiparous and successful IVF control women, respectively. In this case-control study peripheral blood samples were collected from 43 patients who included 23 women with RSA and 20 with IVF failure, plus 43 healthy control women comprising of 36 normal multiparous women and seven women with successful IVF. The expression of CD69, CD94 and CD161 surface markers on CD56+NK cells were assessed using specific monoclonal antibodies by flowcytometry. The percentage of NK cells increased significantly in patients with RSA and in women with IVF failure in comparison to healthy multiparous and successful IVF control groups (p<0.001). The overall expression of CD69, CD94, CD161 were also increased significantly on NK cells in both patient groups compared to control groups (p<0.001). Elevated expression of CD69 and CD161 on NK cells can be considered as immunological risk markers in RSA and IVF failure. However, it is not clear if high expression of CD94 on peripheral blood NK cells is related to abnormal activity of endometrial NK cells.

Cystatin F as a regulator of immune cell cytotoxicity.

PubMed

Kos, Janko; Nanut, Milica Perišić; Prunk, Mateja; Sabotič, Jerica; Dautović, Esmeralda; Jewett, Anahid

2018-05-10

Cysteine cathepsins are lysosomal peptidases involved in the regulation of innate and adaptive immune responses. Among the diverse processes, regulation of granule-dependent cytotoxicity of cytotoxic T-lymphocytes (CTLs) and natural killer (NK) cells during cancer progression has recently gained significant attention. The function of cysteine cathepsins is regulated by endogenous cysteine protease inhibitors-cystatins. Whereas other cystatins are generally cytosolic or extracellular proteins, cystatin F is present in endosomes and lysosomes and is thus able to regulate the activity of its target directly. It is delivered to endosomal/lysosomal vesicles as an inactive, disulphide-linked dimer. Proteolytic cleavage of its N-terminal part leads to the monomer, the only form that is a potent inhibitor of cathepsins C, H and L, involved in the activation of granzymes and perforin. In NK cells and CTLs the levels of active cathepsin C and of granzyme B are dependent on the concentration of monomeric, active cystatin F. In tumour microenvironment, inactive dimeric cystatin F can be secreted from tumour cells or immune cells and further taken up by the cytotoxic cells. Subsequent monomerization and inhibition of cysteine cathepsins within the endosomal/lysosomal vesicles impairs granzyme and perforin activation, and provokes cell anergy. Further, the glycosylation pattern has been shown to be important in controlling secretion of cystatin F from target cells, as well as internalization by cytotoxic cells and trafficking to endosomal/lysosomal vesicles. Cystatin F is therefore an important mediator used by bystander cells to reduce NK and T-cell cytotoxicity.

Functional role of human NK cell receptor 2B4 (CD244) isoforms.

PubMed

Mathew, Stephen O; Rao, Krithi K; Kim, Jong R; Bambard, Nowland D; Mathew, Porunelloor A

2009-06-01

2B4 (CD244), a member of the signaling lymphocyte-activation molecule (SLAM/CD150), is expressed on all NK cells, a subpopulation of T cells, monocytes and basophils. Human NK cells express two isoforms of 2B4, h2B4-A and h2B4-B that differ in a small portion of the extracellular domain. In the present investigation, we have studied the functions of h2B4-A and h2B4-B. Our study demonstrated that these two isoforms differ in their binding affinity for CD48, which results in differential cytotoxic activity as well as intracellular calcium release by NK cells upon target cell recognition. Analysis of the predicted 3-D structure of the two isoforms showed conformational differences that could account for their differences in binding affinity to CD48. h2B4-A was able to mediate natural cytotoxicity against CD48-expressing K562 target cells and induce intracellular calcium release, whereas h2B4-B showed no effects. NK-92MI, U937, THP-1, KU812, primary monocytes, basophils and NK cells showed expression of both h2B4-A and h2B4-B whereas YT and IL-2-activated NK cells did not show any h2B4-B expression. Stimulation of NK cells through 2B4 resulted in decreased mRNA levels of both h2B4-A and h2B4-B indicating that down-regulation of 2B4 isoforms may be an important factor in controlling NK cell activation during immune responses.

The Quantitative and Functional Changes of Postoperative Peripheral Blood Immune Cell Subsets Relate to Prognosis of Patients with Subarachnoid Hemorrhage: A Preliminary Study.

PubMed

Zhou, Yu; Jiang, Yugang; Peng, Yong; Zhang, Mingming

2017-12-01

It has been suggested that the preoperative (PRE) and postoperative (POST) immune system alteration triggered by aneurysmal subarachnoid hemorrhage (SAH) and surgical treatment itself may affect patients' prognosis and contribute to POST complications. The mechanisms may be attributed to immune suppression-triggered infection or immune overreaction-triggered aseptic inflammation. In this study, we investigated the dynamic changes in peripheral immune cell subsets as well as the alterations of inflammatory cytokines in patients with aneurysmal SAH who received craniotomy and clipping surgery. In addition, we studied the association of those changes with POST complications and clinical prognosis. We investigated 27 patients who received craniotomy and clipping surgery for aneurysmal SAH. The operations were all performed within 24 hours after the occurrence of aneurysm rupture. Detailed immune monitoring (peripheral blood leukocytes and lymphocyte subsets and inflammatory cytokines) was performed on PRE (on admission), day 1, day 3, and day 6 after operation. Our data showed that the percentage of CD3+, CD8+, natural killer T (NKT), CD4+, and regulatory T (Treg) cells significantly decreased and the level of interleukin 4 (IL-4), interferon γ, and IL-2 significantly increased 1 day after surgery compared with the data in PRE. On the contrary, natural killer (NK), NK group 2 (NKG2D), and B cells increased and the level of IL-10 in plasma decreased. In study of the relationship between POST fever and the change in immune cell subgroups, the fever group had a lower percentage of CD3+, CD4+, NKT, Tregs, and B cells on day 1, day 3, and day 6 after surgery compared with the patients who did not have fever, whereas the CD8+, NK, and NKG2D subsets showed the opposite trend. Furthermore, we analyzed the association between immune profile changes and the prognosis of those patients. The patients were divided into those with an unfavorable prognosis (n = 6) and those with a favorable prognosis (n = 21) according to Glasgow Outcome Scale score and postoperation (POST) coma. Our results showed that except for B cells, patients with a favorable prognosis had a relatively higher percentage of CD3+, CD4+, CD8+, NK, NKT, NKG2D, and Treg cells compared with the unfavorable prognosis group from PRE to day 6 POST. Our results indicated that patients with aneurysmal SAH undergoing craniotomy and clipping surgery had a profound transient deterioration in immune function. In addition, the changes in immune cell subgroups had a strong association with POST fever. The changes in immune cell subgroups were also directly associated with clinical prognosis of the patients. These association findings might be attributable to a better biomarker to predict patient diagnosis. Copyright © 2017 Elsevier Inc. All rights reserved.

Type 1 Interferons and NK Cells Limit Murine Cytomegalovirus Escape from the Lymph Node Subcapsular Sinus

PubMed Central

Bruce, Kimberley; Lawler, Clara; Cardin, Rhonda D.

2016-01-01

Cytomegaloviruses (CMVs) establish chronic, systemic infections. Peripheral infection spreads via lymph nodes, which are also a focus of host defence. Thus, this is a point at which systemic infection spread might be restricted. Subcapsular sinus macrophages (SSM) captured murine CMV (MCMV) from the afferent lymph and poorly supported its replication. Blocking the type I interferon (IFN-I) receptor (IFNAR) increased MCMV infection of SSM and of the fibroblastic reticular cells (FRC) lining the subcapsular sinus, and accelerated viral spread to the spleen. Little splenic virus derived from SSM, arguing that they mainly induce an anti-viral state in the otherwise susceptible FRC. NK cells also limited infection, killing infected FRC and causing tissue damage. They acted independently of IFN-I, as IFNAR blockade increased NK cell recruitment, and NK cell depletion increased infection in IFNAR-blocked mice. Thus SSM restricted MCMV infection primarily though IFN-I, with NK cells providing a second line of defence. The capacity of innate immunity to restrict MCMV escape from the subcapsular sinus suggested that enhancing its recruitment might improve infection control. PMID:27926941

NK Depletion Results in Increased CCL22 Secretion and Treg Levels in Lewis Lung Carcinoma via the Accumulation of CCL22-secreting CD11b+CD11c+ Cells

PubMed Central

W., Mailloux, Adam; A., Clark, Anna-Maria; Rita, I. Young, M.

2010-01-01

Tumor induced immune suppression involves the accumulation of suppressive infiltrates in the tumor microenvironment such as regulatory T-cells (Tregs). Previous studies demonstrated that NK-dependant increases in CCL22 secretion selectively recruit Tregs toward murine lungs bearing Lewis Lung Carcinoma (LLC). In order to extend the in vitro studies, the present studies utilized in vivo depletion of NK cells to ascertain the contribution of NK-derived CCL22 toward total CCL22 and subsequent Treg levels in both normal and LLC-bearing lungs. However, NK depletion had the unexpected effect of increasing both CCL22 secretion and Treg levels in the lungs of NK-depleted LLC-bearing mice. This was concurrent with an increase in tumor burden. Flow cytometry and a series of both immunomagnetic and FACS isolations were used to identify the CCL22-producing cellular fractions in LLC-bearing lungs. A novel CD11b+CD11c+ cell population was identified that accumulates in large numbers in NK-depleted LLC-bearing lung tissue. These CD11b+CD11c+ cells secreted large amounts of CCL22 that may overcompensate for the loss of NK-derived CCL22 in the lungs of NK-depleted LLC-bearing mice. Taken together these data suggest that NK cells play both a positive and negative role in the regulation of CCL22 secretion and, in turn, the recruitment of Tregs toward LLC-bearing lungs. PMID:20198623

Immunomodulatory properties of medicinal mushrooms: differential effects of water and ethanol extracts on NK cell-mediated cytotoxicity.

PubMed

Lu, Chia-Chen; Hsu, Ya-Jing; Chang, Chih-Jung; Lin, Chuan-Sheng; Martel, Jan; Ojcius, David M; Ko, Yun-Fei; Lai, Hsin-Chih; Young, John D

2016-10-01

Medicinal mushrooms have been used for centuries in Asian countries owing to their beneficial effects on health and longevity. Previous studies have reported that a single medicinal mushroom may produce both stimulatory and inhibitory effects on immune cells, depending on conditions, but the factors responsible for this apparent dichotomy remain obscure. We show here that water and ethanol extracts of cultured mycelium from various species (Agaricus blazei Murrill, Antrodia cinnamomea, Ganoderma lucidum and Hirsutella sinensis) produce opposite effects on NK cells. Water extracts enhance NK cell cytotoxic activity against cancer cells, whereas ethanol extracts inhibit cytotoxicity. Water extracts stimulate the expression and production of cytolytic proteins (perforin and granulysin) and NKG2D/NCR cell surface receptors, and activate intracellular signaling kinases (ERK, JNK and p38). In contrast, ethanol extracts inhibit expression of cytolytic and cell surface receptors. Our results suggest that the mode of extraction of medicinal mushrooms may determine the nature of the immunomodulatory effects produced on immune cells, presumably owing to the differential solubility of stimulatory and inhibitory mediators. These findings have important implications for the preparation of medicinal mushrooms to prevent and treat human diseases. © The Author(s) 2016.

Curcumin and omega-3 fatty acids enhance NK cell-induced apoptosis of pancreatic cancer cells but curcumin inhibits interferon-γ production: benefits of omega-3 with curcumin against cancer.

PubMed

Fiala, Milan

2015-02-12

STAT-3 and STAT-1 signaling have opposite effects in oncogenesis with STAT-3 acting as an oncogene and STAT-1 exerting anti-oncogenic activities through interferon-γ and interferon-α. The cytokine IL-6 promotes oncogenesis by stimulation of NFκB and STAT-3 signaling. Curcuminoids have bi-functional effects by blocking NFκB anti-apoptotic signaling but also blocking anti-oncogenic STAT-1 signaling and interferon-γ production. In our recent study (unpublished work [1]) in pancreatic cancer cell cultures, curcuminoids enhanced cancer cell apoptosis both directly and by potentiating natural killer (NK) cell cytotoxic function. The cytotoxic effects of curcuminoids were increased by incubation of cancer cells and NK cells in an emulsion with omega-3 fatty acids and antioxidants (Smartfish), which enhanced cancer cell apoptosis and protected NK cells against degradation. However, as also shown by others, curcuminoids blocked interferon-γ production by NK cells. The combined use of curcuminoids and omega-3 in cancer immunotherapy will require deeper understanding of their in vivo interactions with the immune system.

An identical miRNA of the human JC and BK polyoma viruses targets the stress-induced ligand ULBP3 to escape immune elimination.

PubMed

Bauman, Yoav; Nachmani, Daphna; Vitenshtein, Alon; Tsukerman, Pinchas; Drayman, Nir; Stern-Ginossar, Noam; Lankry, Dikla; Gruda, Raizy; Mandelboim, Ofer

2011-02-17

The human polyoma viruses JCV and BKV establish asymptomatic persistent infection in 65%-90% of humans but can cause severe illness under immunosuppressive conditions. The mechanisms by which these viruses evade immune recognition are unknown. Here we show that a viral miRNA identical in sequence between JCV and BKV targets the stress-induced ligand ULBP3, which is a protein recognized by the killer receptor NKG2D. Consequently, viral miRNA-mediated ULBP3 downregulation results in reduced NKG2D-mediated killing of virus-infected cells by natural killer (NK) cells. Importantly, when the activity of the viral miRNA was inhibited during infection, NK cells killed the infected cells more efficiently. Because NKG2D is also expressed by various T cell subsets, we propose that JCV and BKV use an identical miRNA that targets ULBP3 to escape detection by both the innate and adaptive immune systems, explaining how these viruses remain latent without being eliminated by the immune system. Copyright © 2011 Elsevier Inc. All rights reserved.

Human natural killer cell development in secondary lymphoid tissues

PubMed Central

Freud, Aharon G.; Yu, Jianhua; Caligiuri, Michael A.

2014-01-01

For nearly a decade it has been appreciated that critical steps in human natural killer (NK) cell development likely occur outside of the bone marrow and potentially necessitate distinct microenvironments within extramedullary tissues. The latter include the liver and gravid uterus as well as secondary lymphoid tissues such as tonsils and lymph nodes. For as yet unknown reasons these tissues are naturally enriched with NK cell developmental intermediates (NKDI) that span a maturation continuum starting from an oligopotent CD34+CD45RA+ hematopoietic precursor cell to a cytolytic mature NK cell. Indeed despite the detection of NKDI within the aforementioned tissues, relatively little is known about how, why, and when these tissues may be most suited to support NK cell maturation and how this process fits in with other components of the human immune system. With the discovery of other innate lymphoid subsets whose immunophenotypes overlap with those of NKDI, there is also need to revisit and potentially re-characterize the basic immunophenotypes of the stages of the human NK cell developmental pathway in vivo. In this review, we provide an overview of human NK cell development in secondary lymphoid tissues and discuss the many questions that remain to be answered in this exciting field. PMID:24661538

NCR1 Expression Identifies Canine Natural Killer Cell Subsets with Phenotypic Similarity to Human Natural Killer Cells

PubMed Central

Foltz, Jennifer A.; Somanchi, Srinivas S.; Yang, Yanwen; Aquino-Lopez, Arianexys; Bishop, Erin E.; Lee, Dean A.

2016-01-01

Canines spontaneously develop many cancers similar to humans – including osteosarcoma, leukemia, and lymphoma – offering the opportunity to study immune therapies in a genetically heterogeneous and immunocompetent environment. However, a lack of antibodies recognizing canine NK cell markers has resulted in suboptimal characterization and unknown purity of NK cell products, hindering the development of canine models of NK cell adoptive immunotherapy. To this end, we generated a novel antibody to canine NCR1 (NKp46), the putative species-wide marker of NK cells, enabling purification of NK cells for further characterization. We demonstrate that CD3−/NKp46+ cells in healthy and osteosarcoma-bearing canines have phenotypic similarity to human CD3−/NKp46+ NK cells, expressing mRNA for CD16 and the natural cytotoxicity receptors NKp30, NKp44, and NKp80. Functionally, we demonstrate with the calcein release assay that canine CD3−/NKp46+ cells kill canine tumor cell lines without prior sensitization and secrete IFN-γ, TNF-α, IL-8, IL-10, and granulocyte-macrophage colony-stimulating factor as measured by Luminex. Similar to human NK cells, CD3−/NKp46+ cells expand rapidly on feeder cells expressing 4-1BBL and membrane-bound IL-21 (median = 20,283-fold in 21 days). Furthermore, we identify a minor Null population (CD3−/CD21−/CD14−/NKp46−) with reduced cytotoxicity against osteosarcoma cells, but similar cytokine secretion as CD3−/NKp46+ cells. Null cells in canines and humans have reduced expression of NKG2D, NKp44, and CD16 compared to NKp46+ NK cells and can be induced to express NKp46 with further expansion on feeder cells. In conclusion, we have identified and characterized canine NK cells, including an NKp46− subset of canine and human NK cells, using a novel anti-canine NKp46 antibody, and report robust ex vivo expansion of canine NK cells sufficient for adoptive immunotherapy. PMID:27933061

Inactivated Sendai virus particle upregulates cancer cell expression of intercellular adhesion molecule-1 and enhances natural killer cell sensitivity on cancer cells.

PubMed

Li, Simin; Nishikawa, Tomoyuki; Kaneda, Yasufumi

2017-12-01

We have already reported that the inactivated Sendai virus (hemagglutinating virus of Japan; HVJ) envelope (HVJ-E) has multiple anticancer effects, including induction of cancer-selective cell death and activation of anticancer immunity. The HVJ-E stimulates dendritic cells to produce cytokines and chemokines such as β-interferon, interleukin-6, chemokine (C-C motif) ligand 5, and chemokine (C-X-C motif) ligand 10, which activate both CD8 + T cells and natural killer (NK) cells and recruit them to the tumor microenvironment. However, the effect of HVJ-E on modulating the sensitivity of cancer cells to immune cell attack has yet to be investigated. In this study, we found that HVJ-E induced the production of intercellular adhesion molecule-1 (ICAM-1, CD54), a ligand of lymphocyte function-associated antigen 1, in several cancer cell lines through the activation of nuclear factor-κB downstream of retinoic acid-inducible gene I and the mitochondrial antiviral signaling pathway. The upregulation of ICAM-1 on the surface of cancer cells increased the sensitivity of cancer cells to NK cells. Knocking out expression of ICAM-1 in MDA-MB-231 cells using the CRISPR/Cas9 method significantly reduced the killing effect of NK cells on ICAM-1-depleted MDA-MB-231 cells. In addition, HVJ-E suppressed tumor growth in MDA-MB-231 tumor-bearing SCID mice, and the HVJ-E antitumor effect was impaired when NK cells were depleted by treatment with the anti-asialo GM1 antibody. Our findings suggest that HVJ-E enhances NK cell sensitivity against cancer cells by increasing ICAM-1 expression on the cancer cell surface. © 2017 The Authors. Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.

NK cells modulate the inflammatory response to corneal epithelial abrasion and thereby support wound healing

USDA-ARS?s Scientific Manuscript database

Natural killer cells are lymphocytes of the innate immune system that have crucial cytotoxic and regulatory roles in adaptive immunity and inflammation. Herein, we consider a role for these cells in corneal wound healing. After a 2-mm central epithelial abrasion of the mouse cornea, a subset of clas...

Immunotoxicity of a standardized citrus polymethoxylated flavone extract.

PubMed

Delaney, B; Phillips, K; Buswell, D; Mowry, B; Nickels, D; Cox, D; Wang, H B; Manthey, J

2001-11-01

Polymethoxylated flavones (PMFs) from citrus inhibit production of TNF-alpha and other pro-inflammatory cytokines. As TNF-alpha also modulates NK cell activity, the current studies were conducted to assess the potential for a standardized citrus PMF mixture to suppress humoral and innate immune functions. PMFs were isolated from orange peel oil using a procedure that obtained a consistent mixture of PMFs both in identity and proportion. The mixture consisted of nobiletin (30.7%), 3,3',4',5,6,7,8-heptamethoxyflavone (27.9%), trimethylscutellarein (14.5%), tangeretin (10.4%), sinensetin (5.8%), 5-demethyl-nobiletin (2.0%), hexa-O-methylquercetagetin (1.3%), 5-demethyl-tetramethylscutellarein (0.6%), and other flavonoids (2.7%). To assess the effect of the PMF mixture on humoral immune responses, female B(6)C(3)F(1) mice (n=8) were exposed to the PMF by gavage at 5, 50, 150 and 500 mg/kg/day for 28 days. On day 25, mice were sensitized to sRBC by tail vein injection and AFC response determined 4 days later. Humoral immunity was insensitive to suppression following exposure to all concentrations of the PMF mixture. Suppression of NK cell activity was observed only following 500 mg/kg/day for 28 days. Body weights were not affected by exposure to any concentration of the PMF mixture in sRBC immunized or non-immunized mice. However, in sRBC-immunized mice, higher concentrations of PMF were associated with a statistically insignificant increase in spleen weight (P>0.05). No change in spleen weight was observed in non-immunized mice. As anticipated, based on previously published in vitro observations, long-term, high-dose exposure to a standardized mixture of citrus PMFs caused a mild suppression of NK cell activity; however, humoral immunity was not sensitive to suppression at the same exposure levels.

Green Tea Catechin Metabolites Exert Immunoregulatory Effects on CD4(+) T Cell and Natural Killer Cell Activities.

PubMed

Kim, Yoon Hee; Won, Yeong-Seon; Yang, Xue; Kumazoe, Motofumi; Yamashita, Shuya; Hara, Aya; Takagaki, Akiko; Goto, Keiichi; Nanjo, Fumio; Tachibana, Hirofumi

2016-05-11

Tea catechins, such as (-)-epigallocatechin-3-O-gallate (EGCG), have been shown to effectively enhance immune activity and prevent cancer, although the underlying mechanism is unclear. Green tea catechins are instead converted to catechin metabolites in the intestine. Here, we show that these green tea catechin metabolites enhance CD4(+) T cell activity as well as natural killer (NK) cell activity. Our data suggest that the absence of a 4'-hydroxyl on this phenyl group (B ring) is important for the effect on immune activity. In particular, 5-(3',5'-dihydroxyphenyl)-γ-valerolactone (EGC-M5), a major metabolite of EGCG, not only increased the activity of CD4(+) T cells but also enhanced the cytotoxic activity of NK cells in vivo. These data suggest that EGC-M5 might show immunostimulatory activity.

Interaction between dendritic cells and natural killer cells during pregnancy in mice.

PubMed

Blois, Sandra M; Barrientos, Gabriela; Garcia, Mariana G; Orsal, Arif S; Tometten, Mareike; Cordo-Russo, Rosalia I; Klapp, Burghard F; Santoni, Angela; Fernández, Nelson; Terness, Peter; Arck, Petra C

2008-07-01

A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.

A Novel Three-Dimensional Immune Oncology Model for High-Throughput Testing of Tumoricidal Activity.

PubMed

Sherman, Hilary; Gitschier, Hannah J; Rossi, Ann E

2018-01-01

The latest advancements in oncology research are focused on autologous immune cell therapy. However, the effectiveness of this type of immunotherapy for cancer remediation is not equivalent for all patients or cancer types. This suggests the need for better preclinical screening models that more closely recapitulate in vivo tumor biology. The established method for investigating tumoricidal activity of immunotherapies has been study of two-dimensional (2D) monolayer cultures of immortalized cancer cell lines or primary tumor cells in standard tissue culture vessels. Indeed, a proven means to examine immune cell migration and invasion are 2D chemotaxis assays in permeabilized supports or Boyden chambers. Nevertheless, the more in vivo -like three-dimensional (3D) multicellular tumor spheroids are quickly becoming the favored model to examine immune cell invasion and tumor cell cytotoxicity. Accordingly, we have developed a 3D immune oncology model by combining 96-well permeable support systems and 96-well low-attachment microplates. The use of the permeable support system enables assessment of immune cell migration, which was tested in this study as chemotactic response of natural killer NK-92MI cells to human stromal-cell derived factor-1 (SDF-1α). Immune invasion was assessed by measuring NK-92MI infiltration into lung carcinoma A549 cell spheroids that were formed in low-attachment microplates. The novel pairing of the permeable support system with low-attachment microplates permitted simultaneous investigation of immune cell homing, immune invasion of tumor spheroids, and spheroid cytotoxicity. In effect, the system represents a more comprehensive and in vivo -like immune oncology model that can be utilized for high-throughput study of tumoricidal activity.

Back to the drawing board: Understanding the complexity of hepatic innate lymphoid cells.

PubMed

Marotel, Marie; Hasan, Uzma; Viel, Sébastien; Marçais, Antoine; Walzer, Thierry

2016-09-01

Recent studies of immune populations in nonlymphoid organs have highlighted the great diversity of the innate lymphoid system. It has also become apparent that mouse and human innate lymphoid cells (ILCs) have distinct phenotypes and properties. In this issue of the European Journal of Immunology, Harmon et al. [Eur. J. Immunol. 2016. 46: 2111-2120] characterized human hepatic NK-cell subsets. The authors report that hepatic CD56(bright) NK cells resemble mouse liver ILC1s in that they express CXCR6 and have an immature phenotype. However, unlike mouse ILC1s, they express high levels of Eomes and low levels of T-bet, and upon stimulation with tumor cells, secrete low amounts of cytokines. These unexpected findings further support the differences between human and mouse immune populations and prompt the study of the role of hepatic ILC subsets in immune responses. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

CD56 Is a Pathogen Recognition Receptor on Human Natural Killer Cells.

PubMed

Ziegler, Sabrina; Weiss, Esther; Schmitt, Anna-Lena; Schlegel, Jan; Burgert, Anne; Terpitz, Ulrich; Sauer, Markus; Moretta, Lorenzo; Sivori, Simona; Leonhardt, Ines; Kurzai, Oliver; Einsele, Hermann; Loeffler, Juergen

2017-07-21

Aspergillus (A.) fumigatus is an opportunistic fungal mold inducing invasive aspergillosis (IA) in immunocompromised patients. Although antifungal activity of human natural killer (NK) cells was shown in previous studies, the underlying cellular mechanisms and pathogen recognition receptors (PRRs) are still unknown. Using flow cytometry we were able to show that the fluorescence positivity of the surface receptor CD56 significantly decreased upon fungal contact. To visualize the interaction site of NK cells and A. fumigatus we used SEM, CLSM and dSTORM techniques, which clearly demonstrated that NK cells directly interact with A. fumigatus via CD56 and that CD56 is re-organized and accumulated at this interaction site time-dependently. The inhibition of the cytoskeleton showed that the receptor re-organization was an active process dependent on actin re-arrangements. Furthermore, we could show that CD56 plays a role in the fungus mediated NK cell activation, since blocking of CD56 surface receptor reduced fungal mediated NK cell activation and reduced cytokine secretion. These results confirmed the direct interaction of NK cells and A. fumigatus, leading to the conclusion that CD56 is a pathogen recognition receptor. These findings give new insights into the functional role of CD56 in the pathogen recognition during the innate immune response.

The Epstein-Barr Virus (EBV) in T Cell and NK Cell Lymphomas: Time for a Reassessment

PubMed Central

Gru, A. A.; Haverkos, B. H.; Freud, A. G.; Hastings, J.; Nowacki, N. B.; Barrionuevo, C.; Vigil, C. E.; Rochford, R.; Natkunam, Y.; Baiocchi, R. A.

2015-01-01

While Epstein-Barr virus (EBV) was initially discovered and characterized as an oncogenic virus in B cell neoplasms, it also plays a complex and multifaceted role in T/NK cell lymphomas. In B cell lymphomas, EBV-encoded proteins have been shown to directly promote immortalization and proliferation through stimulation of the NF-κB pathway and increased expression of anti-apoptotic genes. In the context of mature T/NK lymphomas (MTNKL), with the possible exception on extranodal NK/T cell lymphoma (ENKTL), the virus likely plays a more diverse and nuanced role. EBV has been shown to shape the tumor microenvironment by promoting Th2-skewed T cell responses and by increasing the expression of the immune checkpoint ligand PD-L1. The type of cell infected, the amount of plasma EBV DNA, and the degree of viral lytic replication have all been proposed to have prognostic value in T/NK cell lymphomas. Latency patterns of EBV infection have been defined using EBV-infected B cell models and have not been definitively established in T/NK cell lymphomas. Identifying the expression profile of EBV lytic proteins could allow for individualized therapy with the use of antiviral medications. More work needs to be done to determine whether EBV-associated MTNKL have distinct biological and clinical features, which can be leveraged for risk stratification, disease monitoring, and therapeutic purposes. PMID:26449716

The Activating NKG2C Receptor Is Significantly Reduced in NK Cells after Allogeneic Stem Cell Transplantation in Patients with Severe Graft-versus-Host Disease.

PubMed

Kordelas, Lambros; Steckel, Nina-Kristin; Horn, Peter A; Beelen, Dietrich W; Rebmann, Vera

2016-10-27

Natural killer (NK) cells play a central role in the innate immune system. In allogeneic stem cell transplantation (alloSCT), alloreactive NK cells derived by the graft are discussed to mediate the elimination of leukemic cells and dendritic cells in the patient and thereby to reduce the risk for leukemic relapses and graft-versus-host reactions. The alloreactivity of NK cells is determined by various receptors including the activating CD94/NKG2C and the inhibitory CD94/NKG2A receptors, which both recognize the non-classical human leukocyte antigen E (HLA-E). Here we analyze the contribution of these receptors to NK cell alloreactivity in 26 patients over the course of the first year after alloSCT due to acute myeloid leukemia, myelodysplastic syndrome and T cell Non-Hodgkin-Lymphoma. Our results show that NK cells expressing the activating CD94/NKG2C receptor are significantly reduced in patients after alloSCT with severe acute and chronic graft-versus-host disease (GvHD). Moreover, the ratio of CD94/NKG2C to CD94/NKG2A was reduced in patients with severe acute and chronic GvHD after receiving an HLA-mismatched graft. Collectively, these results provide evidence for the first time that CD94/NKG2C is involved in GvHD prevention.

The Activating NKG2C Receptor Is Significantly Reduced in NK Cells after Allogeneic Stem Cell Transplantation in Patients with Severe Graft-versus-Host Disease

PubMed Central

Kordelas, Lambros; Steckel, Nina-Kristin; Horn, Peter A.; Beelen, Dietrich W.; Rebmann, Vera

2016-01-01

Natural killer (NK) cells play a central role in the innate immune system. In allogeneic stem cell transplantation (alloSCT), alloreactive NK cells derived by the graft are discussed to mediate the elimination of leukemic cells and dendritic cells in the patient and thereby to reduce the risk for leukemic relapses and graft-versus-host reactions. The alloreactivity of NK cells is determined by various receptors including the activating CD94/NKG2C and the inhibitory CD94/NKG2A receptors, which both recognize the non-classical human leukocyte antigen E (HLA-E). Here we analyze the contribution of these receptors to NK cell alloreactivity in 26 patients over the course of the first year after alloSCT due to acute myeloid leukemia, myelodysplastic syndrome and T cell Non-Hodgkin-Lymphoma. Our results show that NK cells expressing the activating CD94/NKG2C receptor are significantly reduced in patients after alloSCT with severe acute and chronic graft-versus-host disease (GvHD). Moreover, the ratio of CD94/NKG2C to CD94/NKG2A was reduced in patients with severe acute and chronic GvHD after receiving an HLA-mismatched graft. Collectively, these results provide evidence for the first time that CD94/NKG2C is involved in GvHD prevention. PMID:27801784

Granulysin Produced by Uterine Natural Killer Cells Induces Apoptosis of Extravillous Trophoblasts in Spontaneous Abortion

PubMed Central

Nakashima, Akitoshi; Shiozaki, Arihiro; Myojo, Subaru; Ito, Mika; Tatematsu, Mikiko; Sakai, Masatoshi; Takamori, Yasushi; Ogawa, Kazuyuki; Nagata, Kinya; Saito, Shigeru

2008-01-01

Immune changes are known to occur in recurrent spontaneous abortion, but it is unclear whether either maternal natural killer (NK) cells or T cells attack fetus-derived trophoblasts. To clarify the immunological causes of spontaneous abortion, we examined the relationship between cytotoxic granule proteins in decidual lymphocytes, such as granulysin, granzyme B, and perforin, and the induction of apoptosis in extravillous trophoblasts (EVTs). The number of granulysin-positive CD56bright NK cells increased significantly in the decidua basalis during spontaneous abortion compared with normal pregnancy; however, granzyme B- and perforin-positive cells did not change. Interestingly, the expression of granulysin was also detected in the nuclei of EVTs in spontaneous abortion samples. When IL-2-stimulated CD56bright NK cells were cocultured with EVT cells (HTR-8/SV40neo), granulysin was found initially in the cytoplasm and then accumulated in the nuclei of the HTR-8/SV40neo cells. Furthermore, transfected cells expressing a GFP-granulysin fusion protein induced apoptosis in HTR-8/SV40neo cells independently of caspases. Our results suggest that granulysin-positive uterine NK cells attack EVTs; subsequently, the uNK-derived granulysin actively accumulates in the nuclei of EVTs, causing the death of EVTs due to apoptosis. These data support a new apoptosis pathway for trophoblasts via uNK-derived granulysin, suggesting that granulysin is involved in spontaneous abortion. PMID:18688023

A. cantoniensis inhibits the proliferation of murine leukemia WEHI-3 cells in vivo and promotes immunoresponses in vivo.

PubMed

Tan, Tzu-Wei; Lin, Yuh-Tzy; Yang, Jai-Sing; Lu, Chi-Cheng; Chiang, Jo-Hua; Wu, Chang-Lin; Lin, Jing-Pin; Tang, Nou-Ying; Yeh, Chin-Chung; Fan, Ming-Jen; Chung, Jing-Gung

2009-01-01

Ampelopsis cantoniensis (AC) has been used as a folk medicine for reducing pain in the Taiwanese population. Our previous studies have shown that the crude extract of AC induced apoptosis in human promyelocytic leukemia HL-60 cells. In this study, the in vivo effects of AC on leukemia WEHI-3 cells and immune responses such as phagocytosis and natural killer (NK) cell activity were investigated. The weights of the livers and spleens were decreased in the AC-treated groups compared to the control groups. The AC treatment increased the percentage of CD3 and CD19 marker cells in WEHI-3-injected mice, indicating that the precursors of T and B cells were inhibited. The AC treatment promoted the activity of macrophage phagocytosis in the peripheral blood mononuclear cells (PBMC) and peritoneal cells. It was found that the NK cells from mice after treatment with AC can kill the YAC-1 target cells. Therefore, the AC treatment increased NK cell activity. In conclusion, AC can affect WEHI-3 cells in vivo and promote macrophage and NK cell activities.

Allelic Variation of Ets1 Does Not Contribute to NK and NKT Cell Deficiencies in Type 1 Diabetes Susceptible NOD Mice

PubMed Central

Jordan, Margaret A.; Poulton, Lynn D.; Fletcher, Julie M.; Baxter, Alan G.

2009-01-01

The NOD mouse is a well characterized model of type 1 diabetes that shares several of the characteristics of Ets1-deficient targeted mutant mice, viz: defects in TCR allelic exclusion, susceptibility to a lupus like disease characterized by IgM and IgG autoantibodies and immune complex-mediated glomerulonephritis, and deficiencies of NK and NKT cells. Here, we sought evidence for allelic variation of Ets1 in mice contributing to the NK and NKT cell phenotypes of the NOD strain. ETS1 expression in NK and NKT cells was reduced in NOD mice, compared to C57BL/6 mice. Although NKT cells numbers were significantly correlated with ETS1 expression in both strains, NKT cell numbers were not linked to the Ets1 gene in a first backcross from NOD to C57BL/6 mice. These results indicate that allelic variation of Ets1 did not contribute to variation in NKT cell numbers in these mice. It remains possible that a third factor not linked to the Ets1 locus controls both ETS1 expression and subsequently NK and NKT cell phenotypes. PMID:19806240

Expression of NK cell receptors on decidual T cells in human pregnancy.

PubMed

Tilburgs, Tamara; van der Mast, Barbara J; Nagtzaam, Nicole M A; Roelen, Dave L; Scherjon, Sicco A; Claas, Frans H J

2009-06-01

Specific receptors enable NK cells to discriminate between cells with normal expression of MHC class I and cells that have low or absent expression of MHC class I molecules. In addition to NK cells, these receptors can be expressed on T cell subsets, mainly on CD8+ T cells but also on gammadeltaTCR+ T cells and CD4+ T cells. Although the function of NK cell receptor expression on T cells is not completely understood, various studies have shown that they are involved in down regulation of T cell receptor (TCR)-mediated activation and influence effector functions, like cytotoxicity and cytokine production. The aim of this study was to analyze expression of NK cell receptors on peripheral blood and decidual T cells during human pregnancy using flow cytometry. We demonstrate that a proportion of decidual T cells express HLA-C specific killer immunoglobulin-like receptors (KIRs). Furthermore, a small proportion of decidual T cells express the HLA-E specific CD94-NKG2A inhibitory and CD94-NKG2C activating receptors. Decidual KIR+ and CD94-NKG2+ T cells mainly display a CD3+CD4-CD8- phenotype. However, decidual tissue also contains higher percentages of KIR and CD94-NKG2 expressing CD4+ and CD8+ T cells compared to peripheral blood. So far, the functional capacities of decidual T cells expressing the NK cell receptors are unknown but NK cell receptor expression on decidual T cells may provide an alternative means by which decidual T cells distinguish self (maternal) cells from allogeneic fetal cells, and act to modulate the decidual immune response.

Neuroblastoma Cell Lines Are Refractory to Genotoxic Drug-Mediated Induction of Ligands for NK Cell-Activating Receptors

PubMed Central

Veneziani, Irene; Brandetti, Elisa; Ognibene, Marzia; Pezzolo, Annalisa; Pistoia, Vito

2018-01-01

Neuroblastoma (NB), the most common extracranial solid tumor of childhood, causes death in almost 15% of children affected by cancer. Treatment of neuroblastoma is based on the combination of chemotherapy with other therapeutic interventions such as surgery, radiotherapy, use of differentiating agents, and immunotherapy. In particular, adoptive NK cell transfer is a new immune-therapeutic approach whose efficacy may be boosted by several anticancer agents able to induce the expression of ligands for NK cell-activating receptors, thus rendering cancer cells more susceptible to NK cell-mediated lysis. Here, we show that chemotherapeutic drugs commonly used for the treatment of NB such as cisplatin, topotecan, irinotecan, and etoposide are unable to induce the expression of activating ligands in a panel of NB cell lines. Consistently, cisplatin-treated NB cell lines were not more susceptible to NK cells than untreated cells. The refractoriness of NB cell lines to these drugs has been partially associated with the abnormal status of genes for ATM, ATR, Chk1, and Chk2, the major transducers of the DNA damage response (DDR), triggered by several anticancer agents and promoting different antitumor mechanisms including the expression of ligands for NK cell-activating receptors. Moreover, both the impaired production of reactive oxygen species (ROS) in some NB cell lines and the transient p53 stabilization in response to our genotoxic drugs under our experimental conditions could contribute to inefficient induction of activating ligands. These data suggest that further investigations, exploiting molecular strategies aimed to potentiate the NK cell-mediated immunotherapy of NB, are warranted. PMID:29805983

Effect of Spaceflight on the Functions of NK and LAK Cells

NASA Technical Reports Server (NTRS)

Pierson, Duane L.; Grimm, Elizabeth A.; Pierson, Duane L.; Paloski, W. H. (Technical Monitor)

1999-01-01

Spaceflight-associated stress alters some aspects of the human immune response. In this study, we determined the effects of 10 days aboard the Space Shuttle on the cytotoxic activity of NK and LAK cells. The subjects of this study were crewmembers of two 10-day shuttle flights. Ten-ml blood specimens were obtained from ten astronauts 10 days before launch, immediately after landing, and 3 days after landing. PBMCs were separated from the blood specimens and stored at -800 C. All PBMCs were thawed simultaneously, and the cytotoxic activities of NK and LAK cells were measured by a 4-hour Cr-51 release assay. K562 cells were used to assess NK-cell cytotoxicity. After 4 days of IL-2 activation, the LAK cell cytotoxic activity was determined using K562 and Daudi cells as the target cells. NK-cell cytotoxicity was decreased at landing (p less than 0.0005) in 9/10 astronauts, and in most cases recovered to preflight levels by 3 days after landing; NK-cell cytotoxicity was increased in one astronaut at landing. LAK cytotoxic activity against K562 cells was decreased at landing in 6/10 astronauts (p=0.018), and activity against Daudi cells was decreased in 7/10 astronauts (p=0.01). Phenotyping of PBMCs and LAK cells showed alterations in some surface markers and adhesion molecules (CD1 1 b, CD1 1 c, CD1 1 a, CD1 6, L-Selectin and CD3). Thus spaceflight leads to a decrease in the functions of NK and LAK cells in most astronauts.