Impaired NK cell cytotoxicity by high level of interferon-γ in concanavalin A-induced hepatitis

2005 ◽  
Vol 83 (11) ◽  
pp. 1045-1053 ◽  
Author(s):  
Zhongjun Dong ◽  
Cai Zhang ◽  
Haiming Wei ◽  
Rui Sun ◽  
Zhigang Tian

Unlike T cells, the role of natural killer (NK) cells is not well documented in the concanavalin (ConA)- induced hepatitis model. This study aimed to investigate the regulatory effect of high levels of interferon-γ (IFN-γ) on NK cells in ConA-induced hepatitis. The cytotoxicities of NK cells from ConA-injected mice or NK cell lines (NK92 and NKL) were detected by the 4-h 51Cr release assay. Depletion of NK cells with AsGM1 antibody was used to assess the NK cell role in ConA-induced hepatitis. Expression of NK cell receptors and cytotoxic molecules was measured by reverse transcription – polymerase chain reaction. Twelve hours after ConA injection, serum IFN-γ was significantly increased in wild mice, but not in severe combined immunodeficiency mice, and hepatic NK cells exerted impaired cytotoxicity against YAC-l cells in wild mice. Eight hours after NK cells were incubated in serum from ConA-treated mice, NK cell cytotoxicity was down-modulated and the effect was abolished by pretreatment with neutralizing serum IFN-γ with specific antibody in vitro. A high concentration of IFN-γ (> 1000 U/mL) inhibited the cytotoxicities of 2 NK cell lines in vitro, accompanied with down-regulation of NKG2D transcripts and up-regulation of NKG2A/B and KIR2DL transcripts. The inhibitive role of IFN-γ was not seen in NKG2D ligand negative cells. These results suggest that NK cell cytotoxicity was inhibited by high levels of IFN-γ in ConA-induced hepatitis, which may relate to the dispensable role of NK cells.Key words: cytotoxicity, hepatoimmunology, interferon-γ, liver injury.

2019 ◽  
Author(s):  
Li-Juan Chen ◽  
Bin Hu ◽  
Zhi-Qiang Han ◽  
Jian Ni ◽  
Yong-Ming Zhou ◽  
...  

Abstract Background: Intriguingly, microRNA-20a (miR-20a) has been recently witnessed to be involved in the pathogenesis of endometriosis (EMS) but the molecular mechanism controlled by miR-20a is to be undefined. The present study is designed to probe into how miR-20a acts to regulate the cytotoxicity of natural killer (NK) cells. Methods: Most of all, consistent with the clinical determination in EMS patients, miR-20a was determined to be down-regulated in NK cells isolated from nude mice. miR-20a could specifically bind to ERG and negatively regulates its expression in NK cells. Additionally, shRNA-mediated silencing of ERG decreased the expression of HLX. HLX up-regulated STAT4 by inducing proteasome degradation and inhibited NK cell cytotoxicity. Results: Of great importance, forced expression of miR-20a consequently induced NK cell cytotoxicity in vitro by increasing perforin expression via enhancement of STAT4 that was caused by impairing the binding of ERG to HLX enhancer. The in vivo experiments further confirmed the promoting role of miR-20a in the cytotoxicity of NK cells isolated from EMS nude mice and subsequent protective role of miR-20a against EMS-induced endometrial injury. Conclusion: The aforementioned data suggest that miR-20a potentiates the cytotoxicity of NK via up-regulating perforin mediated by ERG/HLX/STAT4, highlighting potential novel mechanisms associated with EMS progression.


Blood ◽  
2008 ◽  
Vol 112 (11) ◽  
pp. 3200-3200
Author(s):  
Matthias Krusch ◽  
Julia Salih ◽  
Lothar Kanz ◽  
Helmut R Salih

Abstract CML is characterized by the BCR-ABL fusion protein, which mediates the oncogenic signaling. This led to the development of BCR-ABL inhibitors revolutionizing therapy of CML. However, as recently reported for Dasatinib (Schade et al., Blood 111:1366 (2008); Blake et al., Blood 111:4415 (2008)), these agents may impair the activity of immune effector cells like NK cells and T cells. After initiating oncogenic events, development and progression of clinically apparent malignancy is dependent on the evasion of the tumor cells from immunosurveillance. In light of the important role of NK cell reactivity against leukemia we compared the influence of Imatinib, Nilotinib and Dasatinib on the reactivity of both resting and IL-2 activated NK cells against CML cells to identify the compound with the least immuno-compromising side effects. First, the effects of the compounds on NK cell reactivity in concentrations corresponding to plasma peak levels were studied. Dasatinib (200nM) completely abolished NK cell granule mobilization, cytotoxicity and IFN-γ production, while no substantial inhibition was observed with Imatinib (5μM) and Nilotinib (3.6μM) mediated a minor but significant inhibition (p<0.05, Student’s T-test). Presence of the compounds in concentrations corresponding to IC50 levels (Imatinib 600nM, Nilotinib 30nM, Dasatinib 10nM) revealed no influence of Imatinib and Nilotinib, while Dasatinib still significantly reduced NK cell cytotoxicity and IFN-γ production up to 60%. Since Dasatinib, in addition to BCR-ABL, potently inhibits SRC kinases, which are involved in the activation of MAPK pathways and thus crucial for NK cell cytotoxicity, we determined the influence of the compounds on ERK phosphorylation. While no inhibitory effect was observed using Imatinib and Nilotinib, Dasatinib markedly reduced ERK phosphorylation in NK cells. Our data demonstrate that NK cell anti-tumor reactivity is not inhibited by clinically relevant concentrations of Imatinib. While Nilotinib may mediate a minor effect, Dasatinib substantially impairs NK cell reactivity by inhibition of signaling pathways crucial for NK cell effector functions. For a given patient, the choice and dosing of the most suitable BCR-ABL inhibitor may thus require careful consideration of its influence on the immune system, especially in view of the important role of NK cells in the immunesurveillance of residual leukemia.


2019 ◽  
Vol 25 (2) ◽  
pp. 99-109 ◽  
Author(s):  
Peipei Fang ◽  
Luxia Xiang ◽  
Weilai Chen ◽  
Shaoxun Li ◽  
Shanshan Huang ◽  
...  

This study aimed to explore the role of lncRNA GAS5 in the regulation of the killing effect of NK cells on liver cancer. Compared with a control group, lncRNA GAS5, RUNX3, and NCR1 were down-regulated in NK cells of patients with liver cancer, whereas miR-544 expression was up-regulated in NK cells of patients with liver cancer. Activated NK cells had higher IFN-γ level. Knockdown of GAS5 in activated NK cells decreased IFN-γ secretion, NK cell cytotoxicity, the percentage of CD107a+ NK cells, and the apoptosis rate of HepG2 and Huh7 cells. We also proved the interaction of GAS5 and miR-544, and the negative regulation role of GAS5 on miR-544. GAS5 overexpression in activated NK cells increased RUNX3 expression, IFN-γ secretion, the NK cell cytotoxicity, the percentage of CD107a+ NK cells, and the apoptosis rate of HepG2 cells, while miR-544 mimic abolished the promotion effect of GAS5 overexpression. Finally, in vivo experiments indicated an inhibition effect of GAS5 in tumor growth. LncRNA GAS5 overexpression enhances the killing effect of NK cell on liver cancer through regulating miR-544/RUNX3.


2007 ◽  
Vol 204 (4) ◽  
pp. 893-906 ◽  
Author(s):  
Ulrike Schleicher ◽  
Jan Liese ◽  
Ilka Knippertz ◽  
Claudia Kurzmann ◽  
Andrea Hesse ◽  
...  

Natural killer (NK) cells are sentinel components of the innate response to pathogens, but the cell types, pathogen recognition receptors, and cytokines required for their activation in vivo are poorly defined. Here, we investigated the role of plasmacytoid dendritic cells (pDCs), myeloid DCs (mDCs), Toll-like receptors (TLRs), and of NK cell stimulatory cytokines for the induction of an NK cell response to the protozoan parasite Leishmania infantum. In vitro, pDCs did not endocytose Leishmania promastigotes but nevertheless released interferon (IFN)-α/β and interleukin (IL)-12 in a TLR9-dependent manner. mDCs rapidly internalized Leishmania and, in the presence of TLR9, produced IL-12, but not IFN-α/β. Depletion of pDCs did not impair the activation of NK cells in L. infantum–infected mice. In contrast, L. infantum–induced NK cell cytotoxicity and IFN-γ production were abolished in mDC-depleted mice. The same phenotype was observed in TLR9−/− mice, which lacked IL-12 expression by mDCs, and in IL-12−/− mice, whereas IFN-α/β receptor−/− mice showed only a minor reduction of NK cell IFN-γ expression. This study provides the first direct evidence that mDCs are essential for eliciting NK cell cytotoxicity and IFN-γ release in vivo and demonstrates that TLR9, mDCs, and IL-12 are functionally linked to the activation of NK cells in visceral leishmaniasis.


2021 ◽  
Vol 22 (2) ◽  
pp. 656
Author(s):  
Hantae Jo ◽  
Byungsun Cha ◽  
Haneul Kim ◽  
Sofia Brito ◽  
Byeong Mun Kwak ◽  
...  

Natural killer (NK) cells are lymphocytes that can directly destroy cancer cells. When NK cells are activated, CD56 and CD107a markers are able to recognize cancer cells and release perforin and granzyme B proteins that induce apoptosis in the targeted cells. In this study, we focused on the role of phytoncides in activating NK cells and promoting anticancer effects. We tested the effects of several phytoncide compounds on NK-92mi cells and demonstrated that α-pinene treatment exhibited higher anticancer effects, as observed by the increased levels of perforin, granzyme B, CD56 and CD107a. Furthermore, α-pinene treatment in NK-92mi cells increased NK cell cytotoxicity in two different cell lines, and immunoblot assays revealed that the ERK/AKT pathway is involved in NK cell cytotoxicity in response to phytoncides. Furthermore, CT-26 colon cancer cells were allografted subcutaneously into BALB/c mice, and α-pinene treatment then inhibited allografted tumor growth. Our findings demonstrate that α-pinene activates NK cells and increases NK cell cytotoxicity, suggesting it is a potential compound for cancer immunotherapy.


2020 ◽  
Vol 22 (9) ◽  
pp. 1302-1314 ◽  
Author(s):  
Cavan P Bailey ◽  
Mary Figueroa ◽  
Achintyan Gangadharan ◽  
Yanwen Yang ◽  
Megan M Romero ◽  
...  

Abstract Background Diffuse midline gliomas (DMG), including brainstem diffuse intrinsic pontine glioma (DIPG), are incurable pediatric high-grade gliomas (pHGG). Mutations in the H3 histone tail (H3.1/3.3-K27M) are a feature of DIPG, rendering them therapeutically sensitive to small-molecule inhibition of chromatin modifiers. Pharmacological inhibition of lysine-specific demethylase 1 (LSD1) is clinically relevant but has not been carefully investigated in pHGG or DIPG. Methods Patient-derived DIPG cell lines, orthotopic mouse models, and pHGG datasets were used to evaluate effects of LSD1 inhibitors on cytotoxicity and immune gene expression. Immune cell cytotoxicity was assessed in DIPG cells pretreated with LSD1 inhibitors, and informatics platforms were used to determine immune infiltration of pHGG. Results Selective cytotoxicity and an immunogenic gene signature were established in DIPG cell lines using clinically relevant LSD1 inhibitors. Pediatric HGG patient sequencing data demonstrated survival benefit of this LSD1-dependent gene signature. Pretreatment of DIPG with these inhibitors increased lysis by natural killer (NK) cells. Catalytic LSD1 inhibitors induced tumor regression and augmented NK cell infusion in vivo to reduce tumor burden. CIBERSORT analysis of patient data confirmed NK infiltration is beneficial to patient survival, while CD8 T cells are negatively prognostic. Catalytic LSD1 inhibitors are nonperturbing to NK cells, while scaffolding LSD1 inhibitors are toxic to NK cells and do not induce the gene signature in DIPG cells. Conclusions LSD1 inhibition using catalytic inhibitors is selectively cytotoxic and promotes an immune gene signature that increases NK cell killing in vitro and in vivo, representing a therapeutic opportunity for pHGG. Key Points 1. LSD1 inhibition using several clinically relevant compounds is selectively cytotoxic in DIPG and shows in vivo efficacy as a single agent. 2. An LSD1-controlled gene signature predicts survival in pHGG patients and is seen in neural tissue from LSD1 inhibitor–treated mice. 3. LSD1 inhibition enhances NK cell cytotoxicity against DIPG in vivo and in vitro with correlative genetic biomarkers.


2017 ◽  
Vol 7 (1) ◽  
Author(s):  
Li Yang ◽  
MingJing Shen ◽  
Li Jun Xu ◽  
Xiaodong Yang ◽  
Ying Tsai ◽  
...  

Abstract Major progress has been made clinically in inhibiting the programmed death receptor 1 (PD-1)/PD-L1 interaction to enhance T cell-mediated immune function, yet the effectiveness of anti-PD-L1/PD-1 agents in enhancing natural killer (NK) cell’s function remains largely unknown. Susceptibilities of cisplatin-resistant A549CisR and H157CisR cells vs. parental cells to the cytotoxic action of NK cells were examined. We found cisplatin-resistant cells more resistant to NK cell cytotoxicity than parental cells. There were constitutively higher expressions of PD-L1 in A549CisR and H157CisR cells than in parental cells in vitro, as well as in H157CisR cell-derived tumors than H157P cell-derived tumors. In contrast, we observed that the expression of PD-1 in NK cells was induced after co-culture with cisplatin-resistant cells. We also observed increased susceptibility of cisplatin-resistant cells to NK cell cytotoxicity when neutralizing antibody of PD-1 or PD-L1 was added. Further, we found that the NK group 2, member D (NKG2D) ligand levels were lower in A549CisR and H157CisR cells than in parental cells. Meanwhile, we discovered that the MEK/Erk signaling pathway played a significant role in this regulation, and the addition of a MEK/Erk pathway inhibitor significantly enhanced the PD-L1 Ab effect in enhancing NK cell cytotoxicity to cisplatin-resistant cells.


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 925-925 ◽  
Author(s):  
Andreas Lundqvist ◽  
Kristy Greeneltch ◽  
Maria Berg ◽  
Shivani Srivastava ◽  
Nanae Harashima ◽  
...  

Abstract Killer IgG like receptor (KIR) inactivation of NK cells by self HLA molecules has been proposed as a mechanism through which malignant cells evade host NK cell-mediated immunity. To overcome this limitation, we sought to develop a method to sensitize the patient’s tumor to autologous NK cell cytotoxicity. The proteasome inhibitor bortezomib has recently been shown to enhance the activity of tumor death receptors. We found that exposure of a variety of different leukemia, lymphoma and solid tumor cancer cell lines to sub-apoptotic doses of bortezomib sensitized tumor cells in vitro to lysis by allogeneic NK cells. Importantly, this sensitizing effect also occurs with autologous NK cells normally rendered inactive via tumor KIR ligands; NK cells expanded from patients with metastatic renal cell carcinoma were significantly more cytotoxic against the patient’s own autologous tumor cells when pretreated with bortezomib compared to untreated tumors. This sensitization to autologous NK cell killing was also observed in vivo in two different murine tumor models. A significant delay in tumor growth in C57BL/6 mice bearing LLC1 tumors (figure) and a delay in tumor growth and a significant prolongation (p<0.01) in survival were observed in RENCA tumor bearing Balb/c mice treated with bortezomib and syngeneic NK cell infusions compared to untreated mice or animals treated with bortezomib alone or NK cells alone. An investigation into the mechanism through which NK cell cytotoxicity was potentiated revealed bortezomib enhanced the activity of tumor death receptor-dependent and -independent apoptotic pathways. More specifically, bortezomib sensitized human and murine tumor cells to TRAIL and perforin/granzyme mediated NK cell cytotoxicity respectively. These observations suggest that pretreatment of malignant cells with bortezomib could be used as a strategy to override NK cell inhibition via tumor KIR ligands, thus potentiating the activity of adoptively infused autologous NK cells. A clinical trial evaluating the safety and anti-tumor efficacy of adoptively infused autologous NK cells in patients with advanced malignancies with and without tumor sensitization using bortezomib is currently being explored. Figure: Tumor growth in LLC1 bearing C57BL/6 mice. Fourteen days following s.c. injection of 3x105 LLC1 tumor cells, mice received 15μg (i.p) bortezomib and/or an adoptive infusion of 1x106 NK cells from C57BL/6 mice (i.v) given on day 15. Each dot represents the tumor volume of individual mice measured on day 28 post tumor injection. Tumors were significantly smaller in mice treated with bortezomib followed by NK cells compared to controls or mice that received either NK cells alone or bortezomib alone (p<0.04 for all groups). Figure:. Tumor growth in LLC1 bearing C57BL/6 mice. . / Fourteen days following s.c. injection of 3x105 LLC1 tumor cells, mice received 15μg (i.p) bortezomib and/or an adoptive infusion of 1x106 NK cells from C57BL/6 mice (i.v) given on day 15. Each dot represents the tumor volume of individual mice measured on day 28 post tumor injection. Tumors were significantly smaller in mice treated with bortezomib followed by NK cells compared to controls or mice that received either NK cells alone or bortezomib alone (p<0.04 for all groups).


Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 3714-3714 ◽  
Author(s):  
Lei Wu ◽  
Peter Schafer ◽  
George Muller ◽  
David Stirling ◽  
J. Blake Bartlett

Abstract Lenalidomide (Revlimid® is approved for the treatment of transfusion-dependent patients with anemia due to low- or intermediate-1-risk MDS associated with a del 5q cytogenetic abnormality with or without additional cytogenetic abnormalities, and in combination with dexamethasone is for the treatment of multiple myeloma patients who have received at least one prior therapy. Encouraging early results suggest a potential for clinical efficacy in B cell non-Hodgkin’s lymphoma (NHL). Potential mechanisms of action include anti-angiogenic, anti-proliferative and immunomodulatory activities. Lenalidomide has been shown to enhance Th1-type cytokines and T cell and NK cell activation markers in patients with advanced cancers. Furthermore, lenalidomide has been shown to enhance rituximab-mediated protection in a SCID mouse lymphoma model in vivo. We have utilized an in vitro ADCC system to assess the ability of lenalidomide to directly enhance human NK cell function in response to therapeutic antibodies, such as rituximab (chimeric anti-CD20 mAb). Isolated NK cells produced little or no IFN-γ in response to IgG and/or IL-2 or IL-12. However, pre-treatment of NK cells with lenalidomide greatly enhanced IFN-γ production by NK cells in a dose-dependent manner. In a functional ADCC assay, NHL cell lines (Namalwa, Farage & Raji) were pre-coated with rituximab and exposed to NK cells pre-treated with lenalidomide in the presence of either exogenous IL-2 or IL-12. After 4 hours in culture the viability of the tumor cells was assessed. Lenalidomide consistently and synergistically increased the killing of tumor cells in a dose-dependent manner and up to >4-fold compared to rituximab alone. Rituximab alone had only a small effect in this model and there was no killing of cells in the absence of rituximab. The presence of either exogenous IL-2 or IL-12 was required to see enhanced killing by lenalidomide. In cancer patients lenalidomide has been shown to increase serum IL-12 levels and is also known to induce IL-2 production by T cells in vitro. Potential mechanisms for enhanced ADCC include increased signaling through NK FCγ receptors and/or IL-2 or IL-12 receptors. However, we found that these receptors are unaffected by lenalidomide, although downstream effects on NK signaling pathways are likely and are being actively investigated. In conclusion, we have shown that lenalidomide strongly enhances the ability of rituximab to induce ADCC mediated killing of NHL cells in vitro. This provides a strong rationale for combination of these drugs in patients with NHL and CLL.


Sign in / Sign up

Export Citation Format

Share Document