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Sample records for anti-apoptotic cell natural

  1. Anti-apoptotic signature in thymic squamous cell carcinomas - functional relevance of anti-apoptotic BIRC3 expression in the thymic carcinoma cell line 1889c

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    Bei eHuang

    2013-12-01

    Full Text Available The molecular pathogenesis of thymomas and thymic carcinomas (TCs is poorly understood and results of adjuvant therapy are unsatisfactory in case of metastatic disease and tumor recurrence. For these clinical settings, novel therapeutic strategies are urgently needed. Recently, limited sequencing efforts revealed that a broad spectrum of genes that play key roles in various common cancers are rarely affected in thymomas and thymic carcinomas, suggesting that other oncogenic principles might be important. This made us re-analyze historic expression data obtained in a spectrum of thymomas and thymic squamous cell carcinomas (TSCC with a custom made cDNA microarray. By cluster analysis, different anti-apoptotic signatures were detected in type B3 thymoma and TSCC, including overexpression of BIRC3 in TSCCs. This was confirmed by qRT-PCR in the original and an independent validation set of tumors. In contrast to several other cancer cell lines, the BIRC3-positive TSCC cell line, 1889c showed spontaneous apoptosis after BIRC3 knock-down. Targeting apoptosis genes is worth testing as therapeutic principle in TSCC.

  2. Anti-apoptotic peptides protect against radiation-induced cell death

    International Nuclear Information System (INIS)

    McConnell, Kevin W.; Muenzer, Jared T.; Chang, Kathy C.; Davis, Chris G.; McDunn, Jonathan E.; Coopersmith, Craig M.; Hilliard, Carolyn A.; Hotchkiss, Richard S.; Grigsby, Perry W.; Hunt, Clayton R.

    2007-01-01

    The risk of terrorist attacks utilizing either nuclear or radiological weapons has raised concerns about the current lack of effective radioprotectants. Here it is demonstrated that the BH4 peptide domain of the anti-apoptotic protein Bcl-xL can be delivered to cells by covalent attachment to the TAT peptide transduction domain (TAT-BH4) and provide protection in vitro and in vivo from radiation-induced apoptotic cell death. Isolated human lymphocytes treated with TAT-BH4 were protected against apoptosis following exposure to 15 Gy radiation. In mice exposed to 5 Gy radiation, TAT-BH4 treatment protected splenocytes and thymocytes from radiation-induced apoptotic cell death. Most importantly, in vivo radiation protection was observed in mice whether TAT-BH4 treatment was given prior to or after irradiation. Thus, by targeting steps within the apoptosis signaling pathway it is possible to develop post-exposure treatments to protect radio-sensitive tissues

  3. Anti-apoptotic effects of Z alpha1-antitrypsin in human bronchial epithelial cells.

    LENUS (Irish Health Repository)

    Greene, C M

    2010-05-01

    alpha(1)-antitrypsin (alpha(1)-AT) deficiency is a genetic disease which manifests as early-onset emphysema or liver disease. Although the majority of alpha(1)-AT is produced by the liver, it is also produced by bronchial epithelial cells, amongst others, in the lung. Herein, we investigate the effects of mutant Z alpha(1)-AT (ZAAT) expression on apoptosis in a human bronchial epithelial cell line (16HBE14o-) and delineate the mechanisms involved. Control, M variant alpha(1)-AT (MAAT)- or ZAAT-expressing cells were assessed for apoptosis, caspase-3 activity, cell viability, phosphorylation of Bad, nuclear factor (NF)-kappaB activation and induced expression of a selection of pro- and anti-apoptotic genes. Expression of ZAAT in 16HBE14o- cells, like MAAT, inhibited basal and agonist-induced apoptosis. ZAAT expression also inhibited caspase-3 activity by 57% compared with control cells (p = 0.05) and was a more potent inhibitor than MAAT. Whilst ZAAT had no effect on the activity of Bad, its expression activated NF-kappaB-dependent gene expression above control or MAAT-expressing cells. In 16HBE14o- cells but not HEK293 cells, ZAAT upregulated expression of cIAP-1, an upstream regulator of NF-kappaB. cIAP1 expression was increased in ZAAT versus MAAT bronchial biopsies. The data suggest a novel mechanism by which ZAAT may promote human bronchial epithelial cell survival.

  4. Anti-apoptotic potential of several antidiabetic medicinal plants of the eastern James Bay Cree pharmacopeia in cultured kidney cells.

    Science.gov (United States)

    Li, Shilin; Pasquin, Sarah; Eid, Hoda M; Gauchat, Jean-François; Saleem, Ammar; Haddad, Pierre S

    2018-01-30

    Our team has identified 17 Boreal forest species from the traditional pharmacopeia of the Eastern James Bay Cree that presented promising in vitro and in vivo biological activities in the context of type 2 diabetes (T2D). We now screened the 17 plants extracts for potential anti-apoptotic activity in cultured kidney cells and investigated the underlying mechanisms. MDCK (Madin-Darnby Canine Kidney) cell damage was induced by hypertonic medium (700 mOsm/L) in the presence or absence of maximal nontoxic concentrations of each of the 17 plant extracts. After 18 h' treatment, cells were stained with Annexin V (AnnV) and Propidium iodide (PI) and subjected to flow cytometry to assess the cytoprotective (AnnV - /PI - ) and anti-apoptotic (AnnV + /PI - ) potential of the 17 plant extracts. We then selected a representative subset of species (most cytoprotective, moderately so or neutral) to measure the activity of caspases 3, 8 and 9. Gaultheria hispidula and Abies balsamea are amongst the most powerful cytoprotective and anti-apoptotic plants and appear to exert their modulatory effect primarily by inhibiting caspase 9 in the mitochondrial apoptotic signaling pathway. We conclude that several Cree antidiabetic plants exert anti-apoptotic activity that may be relevant in the context of diabetic nephropathy (DN) that affects a significant proportion of Cree diabetics.

  5. Opium induces apoptosis in Jurkat cells via promotion of pro-apoptotic and inhibition of anti-apoptotic molecules.

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    Arababadi, Mohammad Kazemi; Asadikaram, Gholamreza

    2016-02-01

    The aim of this study was to determine the important molecules involved in apoptosis induction by opium in Jurkat cell line. Jurkat cells were incubated 48 hrs with 2.86×10(-5) g/ml concentration of opium and apoptosis as well as expression levels of related molecules were measured. Our results demonstrated that 50.3±0.2 percent of opium treated Jurkat cells were revealed apoptotic features. The levels of mRNA of several pro-apoptotic and anti-apoptotic molecules were increased and decreased, respectively, in the opium treated cells. The results also demonstrated that expression levels of BCL2, DFFA and NOL3 as anti-apoptotic molecules were increased in the opium treated cells. It seems that opium induces apoptosis in Jurkat cells via both intrinsic and extrinsic pathways. Although opium induces apoptosis in the cells but increased expression of some anti-apoptotic molecules may be a normal resistance of the cell for death.

  6. Evaluation of anti-apoptotic activity of different dietary antioxidants in renal cell carcinoma against hydrogen peroxide

    Science.gov (United States)

    Garg, Neeraj K; Mangal, Sharad; Sahu, Tejram; Mehta, Abhinav; Vyas, Suresh P; Tyagi, Rajeev K

    2011-01-01

    Objective To evaluate the anti-apoptotic and radical scavenging activities of dietary phenolics, namely ascorbic acid,α-tocopherol acetate, citric acid, salicylic acid, and estimate H2O2-induced apoptosis in renal cell carcinoma cells. Methods The intracellular antioxidant potency of antioxidants was investigated. H2O2-induced apoptosis in RCC-26 was assayed with the following parameters: cell viability (% apoptosis), nucleosomal damage and DNA fragmentation, bcl-2 levels and flow cytometery analysis (ROS production evaluation). Results The anticancer properties of antioxidants such as ascorbic acid, α-tocopherol acetate, citric acid, salicylic acid with perdurable responses were investigated. It was observed that these antioxidants had protective effect (anti-apoptotic activity) against hydrogen peroxide (H2O2) in renal cell carcinoma (RCC-26) cell line. Conclusions This study reveals and proves the anticancer properties. However, in cancer cell lines anti-apoptotic activity can indirectly reflect the cancer promoter activity through radicals scavenging, and significantly protect nucleus and bcl-2. PMID:23569726

  7. The anti-apoptotic effect of fluid mechanics preconditioning by cells membrane and mitochondria in rats brain microvascular endothelial cells.

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    Tian, Shan; Zhu, Fengping; Hu, Ruiping; Tian, Song; Chen, Xingxing; Lou, Dan; Cao, Bing; Chen, Qiulei; Li, Bai; Li, Fang; Bai, Yulong; Wu, Yi; Zhu, Yulian

    2018-01-01

    Exercise preconditioning is a simple and effective way to prevent ischemia. This paper further provided the mechanism in hemodynamic aspects at the cellular level. To study the anti-apoptotic effects of fluid mechanics preconditioning, Cultured rats brain microvascular endothelial cells were given fluid intervention in a parallel plate flow chamber before oxygen glucose deprivation. It showed that fluid mechanics preconditioning could inhibit the apoptosis of endothelial cells, and this process might be mediated by the shear stress activation of Tie-2 on cells membrane surface and Bcl-2 on the mitochondria surface. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. A BioDesign Approach to Obtain High Yields of Biosimilars by Anti-apoptotic Cell Engineering: a Case Study to Increase the Production Yield of Anti-TNF Alpha Producing Recombinant CHO Cells.

    Science.gov (United States)

    Gulce Iz, Sultan; Inevi, Muge Anil; Metiner, Pelin Saglam; Tamis, Duygu Ayyildiz; Kisbet, Nazli

    2018-01-01

    Recent developments in medical biotechnology have facilitated to enhance the production of monoclonal antibodies (mAbs) and recombinant proteins in mammalian cells. Human mAbs for clinical applications have focused on three areas, particularly cancer, immunological disorders, and infectious diseases. Tumor necrosis factor alpha (TNF-α), which has both proinflammatory and immunoregulatory functions, is an important target in biopharmaceutical industry. In this study, a humanized anti-TNF-α mAb producing stable CHO cell line which produces a biosimilar of Humira (adalimumab) was used. Adalimumab is a fully human anti-TNF mAb among the top-selling mAb products in recent years as a biosimilar. Products from mammalian cell bioprocesses are a derivative of cell viability and metabolism, which is mainly disrupted by cell death in bioreactors. Thus, different strategies are used to increase the product yield. Suppression of apoptosis, also called anti-apoptotic cell engineering, is the most remarkable strategy to enhance lifetime of cells for a longer production period. In fact, using anti-apoptotic cell engineering as a BioDesign approach was inspired by nature; nature gives prolonged life span to some cells like stem cells, tumor cells, and memory B and T cells, and researchers have been using this strategy for different purposes. In this study, as a biomimicry approach, anti-apoptotic cell engineering was used to increase the anti-TNF-α mAb production from the humanized anti-TNF-α mAb producing stable CHO cell line by Bcl-xL anti-apoptotic protein. It was shown that transient transfection of CHO cells by the Bcl-xL anti-apoptotic protein expressing plasmid prolonged the cell survival rate and protected cells from apoptosis. The transient expression of Bcl-xL using CHO cells enhanced the anti-TNF-α production. The production of anti-TNF-α in CHO cells was increased up to 215 mg/L with an increase of 160% after cells were transfected with Bcl-xL expressing plasmid

  9. Anti-apoptotic BFL-1 is the major effector in activation-induced human mast cell survival.

    Directory of Open Access Journals (Sweden)

    Maria Ekoff

    Full Text Available Mast cells are best known for their role in allergic reactions, where aggregation of FcεRI leads to the release of mast cell mediators causing allergic symptoms. The activation also induces a survival program in the cells, i.e., activation-induced mast cell survival. The aim of the present study was to investigate how the activation-induced survival is mediated. Cord blood-derived mast cells and the mast cell line LAD-2 were activated through FcεRI crosslinking, with or without addition of chemicals that inhibit the activity or expression of selected Bcl-2 family members (ABT-737; roscovitine. Cell viability was assessed using staining and flow cytometry. The expression and function of Bcl-2 family members BFL-1 and MCL-1 were investigated using real-time quantitative PCR and siRNA treatment. The mast cell expression of Bfl-1 was investigated in skin biopsies. FcεRI crosslinking promotes activation-induced survival of human mast cells and this is associated with an upregulation of the anti-apoptotic Bcl-2 family member Bfl-1. ABT-737 alone or in combination with roscovitine decreases viability of human mast cells although activation-induced survival is sustained, indicating a minor role for Bcl-X(L, Bcl-2, Bcl-w and Mcl-1. Reducing BFL-1 but not MCL-1 levels by siRNA inhibited activation-induced mast cell survival. We also demonstrate that mast cell expression of Bfl-1 is elevated in birch-pollen-provocated skin and in lesions of atopic dermatitis and psoriasis patients. Taken together, our results highlight Bfl-1 as a major effector in activation-induced human mast cell survival.

  10. Investigating The Anti-apoptotic Effects of Shigella Flexneri Infection In Epithelial Cells

    Science.gov (United States)

    2009-08-13

    Nakamura, Y . Nakamura, and H. Arakawa. 2002. p53AIP1 regulates the mitochondrial apoptotic pathway. Cancer Res. 62:2883-2889. 48. Micheau, O., S. Lens...hydrogen peroxide; protects from CD95 -induced apoptosis in breast cancer cells IER3 protection of cells from Fas- or TNF-alpha-induced apoptosis; involved...Glutathione peroxidase functions in the detoxification of hydrogen peroxide; protects from CD95 -induced apoptosis in breast cancer cells GSTA1

  11. Anti-oxidative and anti-apoptotic roles of spermatogonial stem cells in reversing cisplatin-induced testicular toxicity.

    Science.gov (United States)

    Hussein, Yousri M; Mohamed, Randa H; Shalaby, Sally M; Abd El-Haleem, Manal R; Abd El Motteleb, Dalia M

    2015-11-01

    Because of reproductive toxic effects of chemotherapy, researchers have taken some techniques to preserve fertility potential. The present study was designed to point out the potential role of spermatogonial stem cell (SSC) therapy in reversing cisplatin (CP)-induced testicular toxicity and restore the spermatogenesis. Sixty rats were randomly divided into three groups: group 1, control group; group 2, rats received CP in a dose of 7 mg/kg/day for 5 consecutive days; group 3, CP was injected at 7 mg/kg per day for 5 consecutive days, and, on the 6th day of the experiment, rats were treated with SSC. Forty days after receiving the last dose of CP, rats were euthanized under anesthesia; testes were collected, and gene expression using real-time polymerase chain reaction for P53, Bax, caspase 9 and cytochrome c, testicular histological findings and oxidative status were determined. Administration of cisplatin caused significant increases in malondialdehyde levels, Bax and caspase 9 genes expression levels concomitant with significant decreases in anti-oxidant enzyme activities, p53 and cytochrome c gene expression levels, along with some histopathological lesions in testicular tissue. SCC attenuated the disturbance in oxidant/anti-oxidant status and testicular apoptosis; this is associated with improvements in the histopathological view of the testicular tissue. The current study highlights evidence that the SCC has anti-oxidative and anti-apoptotic properties that could reverse CP-induced testicular toxicity, in addition to their role in spermatogenesis. Copyright © 2015 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  12. FLASH knockdown sensitizes cells to Fas-mediated apoptosis via down-regulation of the anti-apoptotic proteins, MCL-1 and Cflip short.

    Directory of Open Access Journals (Sweden)

    Song Chen

    Full Text Available FLASH (FLICE-associated huge protein or CASP8AP2 is a large multifunctional protein that is involved in many cellular processes associated with cell death and survival. It has been reported to promote apoptosis, but we show here that depletion of FLASH in HT1080 cells by siRNA interference can also accelerate the process. As shown previously, depletion of FLASH halts growth by down-regulating histone biosynthesis and arrests the cell cycle in S-phase. FLASH knockdown followed by stimulating the cells with Fas ligand or anti-Fas antibodies was found to be associated with a more rapid cleavage of PARP, accelerated activation of caspase-8 and the executioner caspase-3 and rapid progression to cellular disintegration. As is the case for most anti-apoptotic proteins, FLASH was degraded soon after the onset of apoptosis. Depletion of FLASH also resulted in the reduced intracellular levels of the anti-apoptotic proteins, MCL-1 and the short isoform of cFLIP. FLASH knockdown in HT1080 mutant cells defective in p53 did not significantly accelerate Fas mediated apoptosis indicating that the effect was dependent on functional p53. Collectively, these results suggest that under some circumstances, FLASH suppresses apoptosis.

  13. Anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), SOD or catalase on antimycin A-induced HeLa cell death.

    Science.gov (United States)

    Han, Yong Hwan; Kim, Suhn Hee; Kim, Sung Zoo; Park, Woo Hyun

    2009-01-01

    Antimycin A (AMA) is an inhibitor of the electron transport chain in mitochondria. In this study, we investigated the anti-apoptotic effects of pan-caspase inhibitor (Z-VAD), superoxide dismutase (SOD) or catalase on AMA-induced HeLa cell death in relation to the cell cycle. Treatment with Z-VAD, SOD or catalase rescued some HeLa cells from AMA-induced apoptosis, but did not prevent the growth inhibition of HeLa cells by AMA. DNA flow cytometric analysis indicated that treatment with AMA significantly induced an S-phase arrest of the cell cycle at 72 h. Interestingly, Z-VAD, SOD and catalase intensified S-phase arrest in AMA-treated cells. In conclusion, treatment with Z-VAD, SOD or catalase decreased apoptotic levels in AMA-treated cells, which was associated with the enhancement of the S-phase arrest of the cell cycle in these cells.

  14. Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

    Science.gov (United States)

    Lizarte, F.S.; Tirapelli, D.P.C.; Ambrosio, S.R.; Tirapelli, C.R.; Oliveira, F.M.; Novais, P.C.; Peria, F.M.; Oliveira, H.F.; Carlotti, C.G.; Tirapelli, L.F.

    2013-01-01

    Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors. PMID:23314342

  15. Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

    Energy Technology Data Exchange (ETDEWEB)

    Lizarte, F.S. Neto; Tirapelli, D.P.C. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Ambrosio, S.R. [Universidade de Franca, Núcleo de Pesquisa em Ciências e Tecnologia, Franca, SP (Brazil); Tirapelli, C.R. [Universidade de São Paulo, Laboratório de Farmacologia, Departamento de Enfermagem Psiquiátrica e Ciências Humanas, Escola de Enfermagem de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Oliveira, F.M. [Universidade de São Paulo, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Novais, P.C. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Peria, F.M.; Oliveira, H.F. [Universidade de São Paulo, Departamento de Clínica Médica, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil); Carlotti, C.G. Junior; Tirapelli, L.F. [Universidade de São Paulo, Departamento de Cirurgia e Anatomia, Faculdade de Medicina de Ribeirão Preto, Ribeirão Preto, SP (Brazil)

    2013-01-11

    Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors.

  16. Kaurene diterpene induces apoptosis in U87 human malignant glioblastoma cells by suppression of anti-apoptotic signals and activation of cysteine proteases

    International Nuclear Information System (INIS)

    Lizarte, F.S. Neto; Tirapelli, D.P.C.; Ambrosio, S.R.; Tirapelli, C.R.; Oliveira, F.M.; Novais, P.C.; Peria, F.M.; Oliveira, H.F.; Carlotti, C.G. Junior; Tirapelli, L.F.

    2013-01-01

    Gliomas are the most common and malignant primary brain tumors in humans. Studies have shown that classes of kaurene diterpene have anti-tumor activity related to their ability to induce apoptosis. We investigated the response of the human glioblastoma cell line U87 to treatment with ent-kaur-16-en-19-oic acid (kaurenoic acid, KA). We analyzed cell survival and the induction of apoptosis using flow cytometry and annexin V staining. Additionally, the expression of anti-apoptotic (c-FLIP and miR-21) and apoptotic (Fas, caspase-3 and caspase-8) genes was analyzed by relative quantification (real-time PCR) of mRNA levels in U87 cells that were either untreated or treated with KA (30, 50, or 70 µM) for 24, 48, and 72 h. U87 cells treated with KA demonstrated reduced viability, and an increase in annexin V- and annexin V/PI-positive cells was observed. The percentage of apoptotic cells was 9% for control cells, 26% for cells submitted to 48 h of treatment with 50 µM KA, and 31% for cells submitted to 48 h of treatment with 70 µM KA. Similarly, in U87 cells treated with KA for 48 h, we observed an increase in the expression of apoptotic genes (caspase-8, -3) and a decrease in the expression of anti-apoptotic genes (miR-21 and c-FLIP). KA possesses several interesting properties and induces apoptosis through a unique mechanism. Further experiments will be necessary to determine if KA may be used as a lead compound for the development of new chemotherapeutic drugs for the treatment of primary brain tumors

  17. Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2.

    Science.gov (United States)

    Yue, Wen; Zheng, Xi; Lin, Yong; Yang, Chung S; Xu, Qing; Carpizo, Darren; Huang, Huarong; DiPaola, Robert S; Tan, Xiang-Lin

    2015-08-28

    Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer.

  18. Metformin combined with aspirin significantly inhibit pancreatic cancer cell growth in vitro and in vivo by suppressing anti-apoptotic proteins Mcl-1 and Bcl-2

    Science.gov (United States)

    Yue, Wen; Zheng, Xi; Lin, Yong; Yang, Chung S.; Xu, Qing; Carpizo, Darren; Huang, Huarong; DiPaola, Robert S.; Tan, Xiang-Lin

    2015-01-01

    Metformin and aspirin have been studied extensively as cancer preventive or therapeutic agents. However, the effects of their combination on pancreatic cancer cells have not been investigated. Herein, we evaluated the effects of metformin and aspirin, alone or in combination, on cell viability, migration, and apoptosis as well as the molecular changes in mTOR, STAT3 and apoptotic signaling pathways in PANC-1 and BxPC3 cells. Metformin and aspirin, at relatively low concentrations, demonstrated synergistically inhibitory effects on cell viability. Compared to the untreated control or individual drug, the combination of metformin and aspirin significantly inhibited cell migration and colony formation of both PANC-1 and BxPC-3 cells. Metformin combined with aspirin significantly inhibited the phosphorylation of mTOR and STAT3, and induced apoptosis as measured by caspase-3 and PARP cleavage. Remarkably, metformin combined with aspirin significantly downregulated the anti-apoptotic proteins Mcl-1 and Bcl-2, and upregulated the pro-apoptotic proteins Bim and Puma, as well as interrupted their interactions. The downregulation of Mcl-1 and Bcl-2 was independent of AMPK or STAT3 pathway but partially through mTOR signaling and proteasome degradation. In a PANC-1 xenograft mouse model, we demonstrated that the combination of metformin and aspirin significantly inhibited tumor growth and downregulated the protein expression of Mcl-1 and Bcl-2 in tumors. Taken together, the combination of metformin and aspirin significantly inhibited pancreatic cancer cell growth in vitro and in vivo by regulating the pro- and anti-apoptotic Bcl-2 family members, supporting the continued investigation of this two drug combination as chemopreventive or chemotherapeutic agents for pancreatic cancer. PMID:26056043

  19. Tec kinase stimulates cell survival in transfected Hek293T cells and is regulated by the anti-apoptotic growth factor IGF-I in human neutrophils.

    Science.gov (United States)

    Himpe, E; Abdul Rahim, S A; Verdood, P; Mano, H; Kooijman, R

    2013-03-01

    Previously, we showed that the phosphatidylinositol-3 kinase (PI(3)K) pathway mediates the anti-apoptotic effects of IGF-I in human neutrophils independently of its down-stream target Akt. In this study, we investigated whether IGF-I regulates Tec kinase, an alternative down-stream target of PI(3)K, in neutrophils and whether this molecule is able to affect apoptosis. We investigated the translocation of Tec kinases in neutrophils after stimulation with IGF-I. Furthermore, we transiently and stably transfected Hek293T cells with constructs expressing different forms of Tec kinase and measured the level of cell survival and apoptosis/necrosis through trypan blue exclusion test and Annexin-V/propidium iodide labelling, respectively. We show that IGF-I stimulates the translocation of Tec kinase to the membrane in neutrophils in a PI(3)K dependent matter. Overexpression of Tec kinase augments cell survival by inhibition of necrosis. The pro-survival effect is attenuated by the deletion of the kinase domain but not by inactivation of this domain by a single amino acid substitution. Tec kinase can act as a prosurvival factor and is regulated by IGF-I in human neutrophils through PI(3)K activation. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Human Adipose-Derived Stem Cells Delay Retinal Degeneration in Royal College of Surgeons Rats Through Anti-Apoptotic and VEGF-Mediated Neuroprotective Effects.

    Science.gov (United States)

    Li, Z; Wang, J; Gao, F; Zhang, J; Tian, H; Shi, X; Lian, C; Sun, Y; Li, W; Xu, J-Y; Li, P; Zhang, J; Gao, Z; Xu, J; Wang, F; Lu, L; Xu, G-T

    2016-01-01

    Stem cell therapy is a promising therapeutic approach for retinal degeneration (RD). Our study investigated the effects of human adipose derived stem cell (hADSCs) on Royal College of Surgeons (RCS) rats. Green fluorescent protein (GFP)-labeled hADSCs were transplanted subretinally into RCS rats at postnatal (PN) 21 days to explore potential therapeutic effects, while adeno-associated viral vector (AAV2)-vascular endothelial growth factor (VEGF) and siVEGF-hADSCs were used to aid the mechanistic dissections. Visual function was evaluated by Electroretinogram (ERG) recording. Potential transdifferentiations were examined by Immunofluorescence (IF) and gene expressions were analyzed by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). Apoptotic retinal cells were detected by Terminal Deoxynucleotidyl Transferase dUTP Nick End Labeling (TUNEL) assay and the cytokines secreted by hADSCs were measured by Enzyme-linked Immunosorbent Assay (ELISA). The visual function of RCS rats began to decrease one week after their eyes opened at PN week 3 and almost lost in PN 5 weeks, accompanied by the loss of retinal outer nuclear layer (ONL). Subretinal transplantation of hADSCs significantly improved the visual function 2 weeks after the transplantation and such therapeutic effect persisted up to 8 weeks after the treatment (PN 11 weeks), with 3-4 rows of photoreceptors remained in the ONL and reduced apoptosis. Consistent with these phenotypic changes, the gene expression of rod photoreceptor markers Rhodopsin (Rho), Crx and Opsin (Opn1) in RCS rats showed obvious decreasing trends over time after PN 3 weeks, but were elevated with hADSC treatment. hADSC transplantation also repressed the expressions of Bax, Bak and Caspase 3, but not the expression of anti-apoptotic genes, including Bcl-2 and Bcl-XL. Finally, substantial VEGF, hepatocyte growth factor (HGF) and pigment epithelium-derived factor (PEDF) secretions from hADSCs were detected, while endogenous

  1. Suppression of osteoblastic phenotypes and modulation of pro- and anti-apoptotic features in normal human osteoblastic cells under a vector-averaged gravity condition.

    Science.gov (United States)

    Nakamura, Hiroshi; Kumei, Yasuhiro; Morita, Sadao; Shimokawa, Hitoyata; Ohya, Keiichi; Shinomiya, Kenichi

    2003-06-01

    Spaceflight and bed rest induce loss of bone mass. A number of in vivo and in vitro studies have been conducted to clarify the mechanisms, however, the results have been conflicting. The purpose of this study was to investigate the effects of gravity unloading on proliferation, phenotypes, and apoptosis of normal human osteoblastic cells in the presence of 1alpha,25-dihydroxyvitamin D3. We used a vector-averaged gravity condition generated by clinostat rotation to simulate gravity unloading. Clinostat rotation did not affect the cell proliferation. On the first day, the mRNA levels for osteocalcin, ALP, CBFA1, VDR, RANKL, and OPG were reduced by clinostat rotation to 21%, 65%, 62%, 52%, 43%, and 54% of control, respectively. ALP activity was decreased to 75% of control. On the second day, the mRNA levels for osteocalcin and RANKL were reduced to 77% and 61% of control, respectively. The decreased VDR mRNA level might be responsible for the reduction for mRNA levels for osteocalcin, RANKL, and OPG. Clinostat rotation increased the pro-apoptotic index (Bax/Bcl-2 ratio) but did not induce apoptosis due to the simultaneous upregulation of the anti-apoptotic XIAP. Reduction of osteoblast responsiveness to 1alpha,25-dihydroxyvitamin D3 might be involved in osteopenia that is induced by gravity unloading.

  2. Antagonism between apoptotic (Bax/Bcl-2) and anti-apoptotic (IAP) signals in human osteoblastic cells under vector-averaged gravity condition.

    Science.gov (United States)

    Nakamura, Hiroshi; Kumei, Yasuhiro; Morita, Sadao; Shimokawa, Hitoyata; Ohya, Keiichi; Shinomiya, Kenichi

    2003-12-01

    A functional disorder associated with weightlessness is well documented in osteoblasts. The apototic features of this disorder are poorly understood. Harmful stress induces apoptosis in cells via mitochondria and/or Fas. The Bax triggers cytochrome c release from mitochondria, which can be blocked by the Bcl-2. Released cytochrome c then activates the initiator caspase, caspase-9, which can be blocked by the anti-apototic (IAP) family of molecules. The effector caspase, caspase-3, finally exerts DNA fragmentation. We conducted this study to examine the apoptotic effects of vector-averaged gravity on normal human osteoblastic cells. Cell culture flasks were incubated on the clinostat, which generated vector-averaged gravity condition (simulated microgravity) for 12, 24, 48, and 96 hours. Upon termination of clinostat cultures, the cell number and cell viability were assessed. DNA fragmentation was analyzed on the agarose-gel electrophoresis. The mRNA levels for Bax, Bcl-2, XIAP, and caspase-3 genes were analyzed by semi-quantitative RT-PCR. Twenty-four hours after starting clinostat rotation, the ratios of Bax/Bcl-2 mRNA levels (indicator of apoptosis) were significantly increased to 136% of the 1G static controls. However, the XIAP mRNA levels (anti-apoptotic molecule) were increased concomitantly to 138% of the 1G static controls. Thus, cell proliferation or cell viability was not affected by vector-averaged gravity. DNA fragmentation was not observed in clinostat group as well as in control group. Finally, the caspase-3 mRNA levels were not affected by vector-averaged gravity. Simulated microgravity might modulate some apoptotic signals upstream the mitochondrial pathway.

  3. Mechanical stretch endows mesenchymal stem cells stronger angiogenic and anti-apoptotic capacities via NFκB activation

    International Nuclear Information System (INIS)

    Zhu, Zhuoli; Gan, Xueqi; Fan, Hongyi; Yu, Haiyang

    2015-01-01

    Mesenchymal stem cells (MSCs) have been broadly used for tissue regeneration and repair due to their broad differentiation potential and potent paracrine properties such as angiogenic capacity. Strategies to increase their survival rate after transplantation and the angiogenic ability are of priority for the utility of MSCs. In this study, we found that mechanical stretch (10% extension, 30 cycles/min cyclic stretch) preconditioning increase the angiogenic capacity via VEGFA induction. In addition, mechanical stretch also increases the survival rate of mesenchymal stem cells under nutrients deprivation. Consistent with the increase VEGFA expression and resistance to apoptosis, nuclear localization of NFκB activity p65 increased upon mechanical stretch. Inhibition of NFκB activity by BAY 11-708 blocks the pro-angiogenesis and anti-apoptosis function of mechanical stretch. Taken together, our findings here raise the possibility that mechanical stretch preconditioning might enhance the therapeutic efficacy of mesenchymal stem cells. - Highlights: • Mechanical stretch increases the angiogenic capacity via VEGFA induction in MSCs. • Mechanical stretch increases the survival rate of MSCs under nutrients deprivation. • Mechanical stretch manipulates MSCs via the activation of NFκB.

  4. Mechanical stretch endows mesenchymal stem cells stronger angiogenic and anti-apoptotic capacities via NFκB activation

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Zhuoli; Gan, Xueqi [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Fan, Hongyi [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China); Department of Applied Mechanics, College of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Yu, Haiyang, E-mail: yhyang6812@foxmail.com [State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu 610041 (China)

    2015-12-25

    Mesenchymal stem cells (MSCs) have been broadly used for tissue regeneration and repair due to their broad differentiation potential and potent paracrine properties such as angiogenic capacity. Strategies to increase their survival rate after transplantation and the angiogenic ability are of priority for the utility of MSCs. In this study, we found that mechanical stretch (10% extension, 30 cycles/min cyclic stretch) preconditioning increase the angiogenic capacity via VEGFA induction. In addition, mechanical stretch also increases the survival rate of mesenchymal stem cells under nutrients deprivation. Consistent with the increase VEGFA expression and resistance to apoptosis, nuclear localization of NFκB activity p65 increased upon mechanical stretch. Inhibition of NFκB activity by BAY 11-708 blocks the pro-angiogenesis and anti-apoptosis function of mechanical stretch. Taken together, our findings here raise the possibility that mechanical stretch preconditioning might enhance the therapeutic efficacy of mesenchymal stem cells. - Highlights: • Mechanical stretch increases the angiogenic capacity via VEGFA induction in MSCs. • Mechanical stretch increases the survival rate of MSCs under nutrients deprivation. • Mechanical stretch manipulates MSCs via the activation of NFκB.

  5. Anti-apoptotic effect of caspase inhibitors on H₂O₂-treated HeLa cells through early suppression of its oxidative stress.

    Science.gov (United States)

    Park, Woo Hyun

    2014-05-01

    Oxidative stress-induced cytotoxicity in cervical cancer cells may be of toxicological interest. In the present study, the effects of exogenous H2O2 on cell growth and death in HeLa cervical cancer cells were investigated, and the anti-apoptotic effects of various caspase (pan-caspase, caspase-3, -8 or -9) inhibitors on H2O2-treated HeLa cells were also evaluated with regard to reactive oxygen species (ROS) and glutathione (GSH) levels. Based on MTT assays, H2O2 inhibited the growth of HeLa cells with an IC50 value of ~75 µM at 24 h. H2O2 increased the number of dead cells and Annexin V-FITC-positive cells in the HeLa cells, which was accompanied by the activation of caspase-3 and the loss of mitochondrial membrane potential (MMP; ΔΨm). However, relatively higher doses of H2O2 induced necrosis in HeLa cells. Caspase inhibitors significantly prevented H2O2-induced HeLa cell death. H2O2 increased ROS including O2•- at 24 h and increased the activity of catalase in HeLa cells. H2O2 also increased the ROS level at 1 h, and several caspase inhibitors attenuated the increased level at 1 h but not at 6, 12 and 24 h. H2O2 decreased the GSH level in HeLa cells at 1 h, and several caspase inhibitors attenuated the decreased level of GSH at this time. H2O2 induced GSH depletion at 24 h. In conclusion, H2O2 inhibited the growth of HeLa cells via apoptosis and/or necrosis, which was accompanied by intracellular increases in ROS levels and GSH depletion. Caspase inhibitors are suggested to suppress H2O2-induced oxidative stress to rescue HeLa cells at the early time point of 1 h.

  6. Anti-apoptotic signaling as a cytoprotective mechanism in mammalian hibernation

    Directory of Open Access Journals (Sweden)

    Andrew N. Rouble

    2013-02-01

    Full Text Available In the context of normal cell turnover, apoptosis is a natural phenomenon involved in making essential life and death decisions. Apoptotic pathways balance signals which promote cell death (pro-apoptotic pathways or counteract these signals (anti-apoptotic pathways. We proposed that changes in anti-apoptotic proteins would occur during mammalian hibernation to aid cell preservation during prolonged torpor under cellular conditions that are highly injurious to most mammals (e.g. low body temperatures, ischemia. Immunoblotting was used to analyze the expression of proteins associated with pro-survival in six tissues of thirteen-lined ground squirrels, Ictidomys tridecemlineatus. The brain showed a concerted response to torpor with significant increases in the levels of all anti-apoptotic targets analyzed (Bcl-2, Bcl-xL, BI-1, Mcl-1, cIAP1/2, xIAP as well as enhanced phosphorylation of Bcl-2 at S70 and T56. Heart responded similarly with most anti-apoptotic proteins elevated significantly during torpor except for Bcl-xL and xIAP that decreased and Mcl-1 that was unaltered. In liver, BI-1 increased whereas cIAP1/2 decreased. In kidney, there was an increase in BI-1, cIAP and xIAP but decreases in Bcl-xL and p-Bcl-2(T56 content. In brown adipose tissue, protein levels of BI-1, cIAP1/2, and xIAP decreased significantly during torpor (compared with euthermia whereas Bcl-2, Bcl-xL, Mcl-1 were unaltered; however, Bcl-2 showed enhanced phosphorylation at Thr56 but not at Ser70. In skeletal muscle, only xIAP levels changed significantly during torpor (an increase. The data show that anti-apoptotic pathways have organ-specific responses in hibernators with a prominent potential role in heart and brain where coordinated enhancement of anti-apoptotic proteins occurred in response to torpor.

  7. The basic helix-loop-helix transcription factor Nex-1/Math-2 promotes neuronal survival of PC12 cells by modulating the dynamic expression of anti-apoptotic and cell cycle regulators.

    Science.gov (United States)

    Uittenbogaard, Martine; Chiaramello, Anne

    2005-02-01

    The basic helix-loop-helix transcription factor Nex1/Math-2 belongs to the NeuroD subfamily, which plays a critical role during neuronal differentiation and maintenance of the differentiated state. Previously, we demonstrated that Nex1 is a key regulatory component of the nerve growth factor (NGF) pathway. Further supporting this hypothesis, this study shows that Nex1 has survival-inducing properties similar to NGF, as Nex1-overexpressing PC12 cells survive in the absence of trophic factors. We dissected the molecular mechanism by which Nex1 confers neuroprotection upon serum removal and found that constitutive expression of Nex1 maintained the expression of specific G1 phase cyclin-dependent kinase inhibitors and concomitantly induced a dynamic expression profile of key anti-apoptotic regulators. This study provides the first evidence of the underlying mechanism by which a member of the NeuroD-subfamily promotes an active anti-apoptotic program essential to the survival of neurons. Our results suggest that the survival program may be viewed as an integral component of the intrinsic programming of the differentiated state.

  8. 4-Acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol from Isaria japonica mediates apoptosis of rat bladder carcinoma NBT-II cells by decreasing anti-apoptotic Bcl-2 expression and increasing pro-apoptotic Bax expression.

    Science.gov (United States)

    Kim, Hyung-Jin; Jang, Seon Il; Kim, Young-Jun; Pae, Hyun-Ock; Won, Hae-Young; Hong, Kyung-Hwan; Oh, Hyuncheol; Kwon, Tae-Oh; Chung, Hun-Taeg

    2004-01-01

    We studied the effect of 4-acetyl-12,13-epoxyl-9-trichothecene-3, 15-diol (AETD) isolated from Isaria japonica, one of the most popular Chinese fungal medicines, on the induction of apoptosis in rat bladder carcinoma NBT-II cells. AETD was cytotoxic to NBT-II cells, and this cytotoxic effect appears to be attributed to its induction of apoptotic cell death, as AETD induced nuclear morphological changes and internucleosomal DNA fragmentation, and increased the proportion of hypodiploid cells and activity of caspase-3. AETD treatment also decreased the expression of the anti-apoptotic protein Bcl-2 and increased the expression of the pro-apoptotic protein Bax. These results provide important information in understanding the mechanism(s) of AETD-induced apoptosis.

  9. Novel post-transcriptional and post-translational regulation of pro-apoptotic protein BOK and anti-apoptotic protein Mcl-1 determine the fate of breast cancer cells to survive or die

    Science.gov (United States)

    Onyeagucha, Benjamin; Subbarayalu, Panneerdoss; Abdelfattah, Nourhan; Rajamanickam, Subapriya; Timilsina, Santosh; Guzman, Rosa; Zeballos, Carla; Eedunuri, Vijay; Bansal, Sanjay; Mohammad, Tabrez; Chen, Yidong; Vadlamudi, Ratna K.; Rao, Manjeet K.

    2017-01-01

    Deregulation of apoptosis is central to cancer progression and a major obstacle to effective treatment. The Bcl-2 gene family members play important roles in the regulation of apoptosis and are frequently altered in cancers. One such member is pro-apoptotic protein Bcl-2-related Ovarian Killer (BOK). Despite its critical role in apoptosis, the regulation of BOK expression is poorly understood in cancers. Here, we discovered that miR-296-5p regulates BOK expression by binding to its 3’-UTR in breast cancers. Interestingly, miR-296-5p also regulates the expression of anti-apoptotic protein myeloid cell leukemia 1 (Mcl-1), which is highly expressed in breast cancers. Our results reveal that Mcl-1 and BOK constitute a regulatory feedback loop as ectopic BOK expression induces Mcl-1, whereas silencing of Mcl-1 results in reduced BOK levels in breast cancer cells. In addition, we show that silencing of Mcl-1 but not BOK reduced the long-term growth of breast cancer cells. Silencing of both Mcl-1 and BOK rescued the effect of Mcl-1 silencing on breast cancer cell growth, suggesting that BOK is important for attenuating cell growth in the absence of Mcl-1. Depletion of BOK suppressed caspase-3 activation in the presence of paclitaxel and in turn protected cells from paclitaxel-induced apoptosis. Furthermore, we demonstrate that glycogen synthase kinase (GSK3) α/β interacts with BOK and regulates its level post-translationally in breast cancer cells. Taken together, our results suggest that fine tuning of the levels of pro-apoptotic protein BOK and anti-apoptotic protein Mcl-1 may decide the fate of cancer cells to either undergo apoptosis or proliferation. PMID:29156771

  10. Characterization of anti-apoptotic action of TCDD as a defensive cellular stress response reaction against the cell damaging action of ultra-violet irradiation in an immortalized normal human mammary epithelial cell line, MCF10A.

    Science.gov (United States)

    Park, Sujin; Matsumura, Fumio

    2006-01-16

    It was originally shown by Woerner and Schrenk [Woerner, W., Schrenk, D., 1998. 2,3,7,8-Tetrachlorodibenzo-p-dioxin suppresses apoptosis and leads to hyperphosphorylation of p53 in rat hepatocytes. Environ. Toxicol. Pharmacol. 6, 239-247] that TCDD (2,3,7,8-tetrachlorodibenzo-p-dioxin) acts as an antagonist against the action of UV-irradiation to induce apoptosis in rat primary hepatocytes. Since prevention of apoptosis has been shown to promote carcinogenesis, we have decided to investigate this phenomenon in a human mammary gland epithelial cell line, MCF10A. We found that, in this cell line, TCDD can antagonize apoptosis that was induced by a variety of treatments, such as UV- and gamma-irradiation, growth factor starvation and trypsinization, or by the addition of H(2)O(2), TGFbeta, and staurosporine. Furthermore, other agents that are known to elicit defensive cellular responses, such as LPS, Fe(3+), nitric oxide and hypoxia could also antagonize UV induced apoptosis just as in the case of TCDD. In addition, we found that, in this cell line, such anti-apoptotic action of TCDD resembles that of exogenously added EGF or TGF alpha. To study the basic mechanism of such an action of TCDD, we tested a variety of diagnostic agents to reverse the effect of TCDD. Antagonists of TCDD which were found to be effective in this way were (a) inhibitors of c-Src kinase, such as PP-2 and CGP77675, (b) those known to block the action of TGF alpha, such as anti-TGF alpha antibody, and alpha(1)-antitrypsin, (c) PD98059, a specific inhibitor of ERK activation, but not SB202190 (an inhibitor of p38 MAPK activation) or SP600125 (a JNK inhibitor) and (d) Ah receptor antagonists, alpha-naphthoflavone and 1, 10-phenanthroline. These results support the notion that TCDD acts as an anti-apoptotic agent by mimicking the action of EGF through activation of the c-Src/ERK signaling pathway.

  11. High expression of PRPS1 induces an anti-apoptotic effect in B-ALL cell lines and predicts an adverse prognosis in Chinese children with B-ALL.

    Science.gov (United States)

    Ma, Yimei; An, Xizhou; Guan, Xianmin; Kong, Qinglin; Wang, Yanzhen; Li, Pengfei; Meng, Yan; Cui, Yinghui; Wen, Xianhao; Guo, Yuxia; Shen, Yali; Yu, Jie

    2018-04-01

    Phosphoribosyl pyrophosphate synthetase 1 (PRPS1) is closely associated with a number of diseases; however, its influence in B-cell acute lymphoblastic leukemia (B-ALL) and the potential molecular mechanisms involved remain unclear. The present study aimed to evaluate the expression of PRPS1 in Chinese children with B-ALL and to investigate the mechanism of action of PRPS1 in this disease. A Cell Counting Kit-8 (CCK-8) assay was performed to examine the proliferation of B-ALL Sup-B15 and Raji cells, and flow cytometric analysis was conducted to determine the cell cycle distribution and rate of apoptosis. The mRNA and protein expression levels of PRPS1, MYC proto-oncogene, bHLH transcription factor, cyclin E1, B-cell lymphoma-2 (Bcl-2), cyclin dependent kinase 2 and caspase-3 were detected by reverse transcription-quantitative polymerase chain reaction and western blot analysis, respectively. Elevated PRPS1 expression was associated with a high-risk stratification and poor prognosis in patients with B-ALL. Furthermore, overexpression of PRPS1 accelerated the growth of and inhibited apoptosis in Sup-B15 and Raji cells as well as increasing the expression of Bcl-2 to induce an anti-apoptotic effect in B-ALL cell lines. The results of the present study indicate that PRPS1 regulates multiple processes in B-ALL and may be an attractive therapeutic target.

  12. The anti-apoptotic members of the Bcl-2 family are attractive tumor-associated antigens

    DEFF Research Database (Denmark)

    Straten, Per thor; Andersen, Mads Hald; Andersen, Mads Hald

    2010-01-01

    Anti-apoptotic members of the Bcl-2 family (Bcl-2, Bcl-X(L) and Mcl-2) are pivotal regulators of apoptotic cell death. They are all highly overexpressed in cancers of different origin in which they enhance the survival of the cancer cells. Consequently, they represent prime candidates for anti......-cancer therapy and specific antisense oligonucleotides or small molecule inhibitors have shown broad anti-cancer activities in pre-clinical models and are currently tested in clinical trials. In addition, immune-mediated tumor destruction is emerging as an interesting modality to treat cancer patients. Notably......, spontaneous cellular immune responses against the Bcl-2 family proteins have been identified as frequent features in cancer patients underscoring that these proteins are natural targets for the immune system. Thus, Bcl-2 family may serve as an important and widely applicable target for anti...

  13. Modulation of Ca2+ Signaling by Anti-apoptotic B-Cell Lymphoma 2 Proteins at the Endoplasmic Reticulum–Mitochondrial Interface

    Directory of Open Access Journals (Sweden)

    Tim Vervliet

    2017-05-01

    Full Text Available Mitochondria are important regulators of cell death and cell survival. Mitochondrial Ca2+ levels are critically involved in both of these processes. On the one hand, excessive mitochondrial Ca2+ leads to Ca2+-induced mitochondrial outer membrane permeabilization and thus apoptosis. On the other hand, mitochondria need Ca2+ in order to efficiently fuel the tricarboxylic acid cycle and maintain adequate mitochondrial bioenergetics. For obtaining this Ca2+, the mitochondria are largely dependent on close contact sites with the endoplasmic reticulum (ER, the so-called mitochondria-associated ER membranes. There, the inositol 1,4,5-trisphosphate receptors are responsible for the Ca2+ release from the ER. It comes as no surprise that this Ca2+ release from the ER and the subsequent Ca2+ uptake at the mitochondria are finely regulated. Cancer cells often modulate ER-Ca2+ transfer to the mitochondria in order to promote cell survival and to inhibit cell death. Important regulators of these Ca2+ signals and the onset of cancer are the B-cell lymphoma 2 (Bcl-2 family of proteins. An increasing number of reports highlight the ability of these Bcl-2-protein family members to finely regulate Ca2+ transfer from ER to mitochondria both in healthy cells and in cancer. In this review, we focus on recent insights into the dynamic regulation of ER–mitochondrial Ca2+ fluxes by Bcl-2-family members and how this impacts cell survival, cell death and mitochondrial energy production.

  14. Permissive effect of EGFR-activated pathways on RVI and their anti-apoptotic effect in hypertonicity-exposed mIMCD3 cells.

    Science.gov (United States)

    Ruiz-Martínez, Alejandro; Vázquez-Juárez, Erika; Ramos-Mandujano, Gerardo; Pasantes-Morales, Herminia

    2011-12-01

    Hypertonicity is a stressful stimulus leading to cell shrinkage and apoptotic cell death. Apoptosis can be prevented if cells are able to activate the mechanism of RVI (regulatory volume increase). This study in mIMCD3 cells presents evidence of a permissive role of the EGFR (epidermal growth factor receptor) on RVI, achieved for the most part through the two main EGFR-triggered signalling chains, the MAPK (mitogen-activated protein kinase)/ERK (extracellular-signal-regulated kinase) and the PI3K (phosphoinositide 3-kinase)/Akt (also known as protein kinase B) pathways. Hyperosmotic solutions (450 mosM) made by addition of NaCl, increased EGFR phosphorylation, which is prevented by GM6001 and AG1478, blockers respectively, of MMPs (matrix metalloproteinases) and EGFR. Inhibition of EGFR, ERK (PD98059) or PI3K/Akt (wortmannin) phosphorylation reduced RVI by 60, 48 and 58% respectively. The NHE (Na(+)/H(+) exchanger) seems to be the essential mediator of this effect since (i) NHE is the main contributor to RVI, (ii) EGFR, ERK and PI3K/Akt blockers added together with the NHE blocker zoniporide reduce RVI by non-additive effects and (iii) All the blockers significantly lowered the NHE rate in cells challenged by an NH(4)Cl pulse. Besides reducing RVI, the inhibition of MMP, EGFR and PI3K/Akt had a strong pro-apoptotic effect increasing cell death by 2-3.7-fold. This effect was significantly lower when RVI inhibition did not involve the EGFR-PI3K/Akt pathway. These results provide evidence that Akt and its permissive effect on RVI have a predominant influence on cell survival under hypertonic conditions in IMCD3 cells. This role of Akt operates under the influence of EGFR activation, promoted by MMP. © The Authors Journal compilation © 2011 Biochemical Society

  15. Neuroprotective Effects of Vanillyl Alcohol in Gastrodia elata Blume Through Suppression of Oxidative Stress and Anti-Apoptotic Activity in Toxin-Induced Dopaminergic MN9D Cells

    Directory of Open Access Journals (Sweden)

    Hun Jong Jung

    2011-06-01

    Full Text Available Gastrodia elata Blume (GE has long been used in oriental countries as a traditional herbal medicine to relieve symptoms associated with neurological ailments such as vertigo, general paralysis and epilepsy. In this study, we have investigated the effects of GE extracts and its major bioactive components on 1-methyl-4-phenylpyridinium (MPP+-treated MN9D dopaminergic cells, a classic in vitro model for Parkinson’s disease (PD. We found that vanillyl alcohol effectively inhibited the cytotoxicity and improved cell viability in MPP+-induced MN9D dopaminergic cells. The underlying mechanisms of vanillyl alcohol action were also studied. Vanillyl alcohol attenuated the elevation of reactive oxygen species (ROS levels, decreased in the Bax/Bcl-2 ratio and poly (ADP-ribose polymerase proteolysis. These results indicate that vanillyl alcohol protected dopaminergic MN9D cells against MPP+-induced apoptosis by relieving oxidative stress and modulating the apoptotic process and is therefore a potential candidate for treatment of neurodegenerative diseases such as Parkinson’s disease.

  16. Pro- and anti-apoptotic effects of p53 in cisplatin-treated human testicular cancer are cell context-dependent

    NARCIS (Netherlands)

    di Pietro, Alessandra; Koster, Roelof; Boersma-van Eck, Wytske; Dam, Wendy A.; Mulder, Nanno H.; Gietema, Jourik A.; de Vries, Elisabeth G. E.; de Jong, Steven

    2012-01-01

    In murine testicular cancer (TC) cells wild-type p53 contributes to sensitivity to DNA-damaging drugs in a dose-dependent way. In human TC, however, the role of wild-type p53 functionality in chemotherapeutic response remains elusive. We analyzed functionality of wild-type p53 in cisplatin

  17. Molecular characterization of severin from Clonorchis sinensis excretory/secretory products and its potential anti-apoptotic role in hepatocarcinoma PLC cells.

    Directory of Open Access Journals (Sweden)

    Xueqing Chen

    Full Text Available BACKGROUND: Clonorchiasis, caused by the infection of Clonorchis sinensis (C. sinensis, is a kind of neglected tropical disease, but it is highly related to cholangiocarcinoma and hepatocellular carcinoma (HCC. It has been well known that the excretory/secretory products of C. sinensis (CsESPs play key roles in clonorchiasis associated carcinoma. From genome and transcriptome of C. sinensis, we identified one component of CsESPs, severin (Csseverin, which had three putative gelsolin domains. Its homologues are supposed to play a vital role in apoptosis resistance of tumour cell. METHODOLOGY/PRINCIPAL FINDINGS: There was significant similarity in tertiary structures between human gelsolin and Csseverin by bioinformatics analysis. We identified that Csseverin expressed at life stage of adult worm, metacercaria and egg by the method of quantitative real-time PCR and western blotting. Csseverin distributed in vitellarium and intrauterine eggs of adult worm and tegument of metacercaria by immunofluorence assay. We obtained recombinant Csseverin (rCsseverin and confirmed that rCsseverin could bind with calciumion in circular dichroism spectrum analysis. It was demonstrated that rCsseverin was of the capability of actin binding by gel overlay assay and immunocytochemistry. Both Annexin V/PI assay and mitochondrial membrane potential assay of human hepatocarcinoma cell line PLC showed apoptosis resistance after incubation with different concentrations of rCsseverin. Morphological analysis, apoptosis-associated changes of mitochondrial membrane potential and Annexin V/PI apoptosis assay showed that co-incubation of PLC cells with rCsseverin in vitro led to an inhibition of apoptosis induced by serum-starved for 24 h. CONCLUSIONS/SIGNIFICANCE: Collectively, the molecular properties of Csseverin, a molecule of CsESPs, were characterized in our study. rCsseverin could cause obvious apoptotic inhibition in human HCC cell line. Csseverin might exacerbate the

  18. Synthetic peptide, Ala-Arg-Glu-Gly-Glu-Met, abolishes pro-proliferative and anti-apoptotic effects of high glucose in vascular smooth muscle cells.

    Science.gov (United States)

    Cao, Xiaozhou; Lyu, Yi; Ning, Junyu; Tang, Xiaozhi; Shen, Xinchun

    2017-03-25

    Apoptosis plays a critical role in normal vascular development and atherosclerosis. However, high glucose has been reported to generate a certain level of ROS that can inhibit vascular smooth muscle cell (VSMC) apoptosis, with the underlying mechanism remaining unclear. In this study, a synthetic peptide AREGEM (Ala-Arg-Glu-Gly-Glu-Met) exhibited antioxidative effects and was used to investigate its function in VSMCs during hyperglycaemia. MTT assay results demonstrated that AREGEM significantly attenuated high glucose-induced VSMCs proliferation. Flow cytometry displayed that high glucose levels inhibited cell apoptosis, whereas this effect was attenuated by pre-incubation with AREGEM. In addition, the 2',7'-dichlorofluorescein diacetate (DCFH-DA) fluorescent probe assay further demonstrated that AREGEM reduced intracellular ROS accumulation in VSMCs. Furthermore, this peptide was able to prevent the decrease of caspase-3 activity and the increase of the ratio of Bcl-2/Bax protein in VSMCs exposed to high glucose. These findings demonstrated that AREGEM is able to abolish the effects of high glucose in VSMCs; therefore, this peptide can be a potential candidate to develop a novel strategy for curing diabetic related diseases. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Discovery of Aromatic Carbamates that Confer Neuroprotective Activity by Enhancing Autophagy and Inducing the Anti-Apoptotic Protein B-Cell Lymphoma 2 (Bcl-2).

    Science.gov (United States)

    Kinarivala, Nihar; Patel, Ronak; Boustany, Rose-Mary; Al-Ahmad, Abraham; Trippier, Paul C

    2017-12-14

    Neurodegenerative diseases share certain pathophysiological hallmarks that represent common targets for drug discovery. In particular, dysfunction of proteostasis and the resultant apoptotic death of neurons represent common pathways for pharmacological intervention. A library of aromatic carbamate derivatives based on the clinically available drug flupirtine was synthesized to determine a structure-activity relationship for neuroprotective activity. Several derivatives were identified that possess greater protective effect in human induced pluripotent stem cell-derived neurons, protecting up to 80% of neurons against etoposide-induced apoptosis at concentrations as low as 100 nM. The developed aromatic carbamates possess physicochemical properties desirable for CNS therapeutics. The primary known mechanisms of action of the parent scaffold are not responsible for the observed neuroprotective activity. Herein, we demonstrate that neuroprotective aromatic carbamates function to increase the Bcl-2/Bax ratio to an antiapoptotic state and activate autophagy through induction of beclin 1.

  20. Human T-cell leukemia virus type I tax protein induces the expression of anti-apoptotic gene Bcl-xL in human T-cells through nuclear factor-kappaB and c-AMP responsive element binding protein pathways.

    Science.gov (United States)

    Mori, N; Fujii, M; Cheng, G; Ikeda, S; Yamasaki, Y; Yamada, Y; Tomonaga, M; Yamamoto, N

    2001-06-01

    Human T-cell leukemia virus type I (HTLV-I) is the etiologic agent of adult T-cell leukemia (ATL), which is an aggressive form of human T-cell malignancy. The viral protein, Tax, immortalizes human T-cells and inhibits various types of apoptosis, and is thought to play crucial roles in the development of ATL. We have recently demonstrated that Tax induces the constitutive expression of the anti-apoptotic protein, Bcl-xL, in a mouse T-cell line. The mouse, however, is not a natural host of HTLV-I, and HTLV-I does not induce this malignancy in mice. We thus examined whether Tax also activates the expression of Bcl-xL in human T-cells. Expression of Tax in a human T-cell line, Jurkat, induced the expression of the Bcl-xL gene, but did not significantly affect the expression of the other apoptosis-related genes, Bcl-2 and Bax. Transient transfection assays showed that Tax stimulated human Bcl-xL promoter activity in Jurkat cells. Deletion of the two potential nuclear factor (NF)-kappaB binding sites in the human Bcl-xL promoter significantly decreased Tax-induced transactivation. In addition to NF-kappaB, Tax activates transcription through the c-AMP responsive element binding protein (CREB). Tax mutants segregating these two pathways showed that both the NF-kappaB and CREB pathways of Tax are required for maximum activation of a human Bcl-xL promoter, nevertheless, NF-kappaB alone was sufficient for that of a mouse Bcl-xL promoter. Northern blot analysis showed that all the human T-cell lines expressing Tax had higher levels of Bcl-xL mRNA than HTLV-I-uninfected ones. Furthermore, the sample from one patient with ATL expressed higher levels of Bcl-xL mRNA compared with levels from uninfected peripheral blood mononuclear cells. Our results suggest that Tax induces the expression of Bc-xL through the NF-kappaB and CREB pathways in HTLV-I-infected human T-cells, and then inhibits apoptosis, and such inhibition is necessary for the infected cells to advance to the

  1. Identification of a conserved anti-apoptotic protein that modulates the mitochondrial apoptosis pathway.

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    Full Text Available Here we identified an evolutionarily highly conserved and ubiquitously expressed protein (C9orf82 that shows structural similarities to the death effector domain of apoptosis-related proteins. RNAi knockdown of C9orf82 induced apoptosis in A-549 and MCF7/casp3-10b lung and breast carcinoma cells, respectively, but not in cells lacking caspase-3, caspase-10 or both. Apoptosis was associated with activated caspases-3, -8, -9 and -10, and inactivation of caspases 10 or 3 was sufficient to block apoptosis in this pathway. Apoptosis upon knockdown of C9orf82 was associated with increased caspase-10 expression and activation, which was required for the generation of an 11 kDa tBid fragment and activation of Caspase-9. These data suggest that C9orf82 functions as an anti-apoptotic protein that modulates a caspase-10 dependent mitochondrial caspase-3/9 feedback amplification loop. We designate this ubiquitously expressed and evolutionarily conserved anti-apoptotic protein Conserved Anti-Apoptotic Protein (CAAP. We also demonstrated that treatment of MCF7/casp3-10b cells with staurosporine and etoposides induced apoptosis and knockdown of CAAP expression. This implies that the CAAP protein could be a target for chemotherapeutic agents.

  2. Golgi anti-apoptotic protein: a tale of camels, calcium, channels and cancer.

    Science.gov (United States)

    Carrara, Guia; Parsons, Maddy; Saraiva, Nuno; Smith, Geoffrey L

    2017-05-01

    Golgi anti-apoptotic protein (GAAP), also known as transmembrane Bax inhibitor-1 motif-containing 4 (TMBIM4) or Lifeguard 4 (Lfg4), shares remarkable amino acid conservation with orthologues throughout eukaryotes, prokaryotes and some orthopoxviruses, suggesting a highly conserved function. GAAPs regulate Ca 2+ levels and fluxes from the Golgi and endoplasmic reticulum, confer resistance to a broad range of apoptotic stimuli, promote cell adhesion and migration via the activation of store-operated Ca 2+ entry, are essential for the viability of human cells, and affect orthopoxvirus virulence. GAAPs are oligomeric, multi-transmembrane proteins that are resident in Golgi membranes and form cation-selective ion channels that may explain the multiple functions of these proteins. Residues contributing to the ion-conducting pore have been defined and provide the first clues about the mechanistic link between these very different functions of GAAP. Although GAAPs are naturally oligomeric, they can also function as monomers, a feature that distinguishes them from other virus-encoded ion channels that must oligomerize for function. This review summarizes the known functions of GAAPs and discusses their potential importance in disease. © 2017 The Authors.

  3. Protective effects of melittin on transforming growth factor-β1 injury to hepatocytes via anti-apoptotic mechanism

    International Nuclear Information System (INIS)

    Lee, Woo-Ram; Park, Ji-Hyun; Kim, Kyung-Hyun; Park, Yoon-Yub; Han, Sang-Mi; Park, Kwan-kyu

    2011-01-01

    Melittin is a cationic, hemolytic peptide that is the main toxic component in the venom of the honey bee (Apis mellifera). Melittin has multiple effects, including anti-bacterial, anti-viral and anti-inflammatory, in various cell types. However, the anti-apoptotic mechanisms of melittin have not been fully elucidated in hepatocytes. Apoptosis contributes to liver inflammation and fibrosis. Knowledge of the apoptotic mechanisms is important to develop new and effective therapies for treatment of cirrhosis, portal hypertension, liver cancer, and other liver diseases. In the present study, we investigated the anti-apoptotic effect of melittin on transforming growth factor (TGF)-β1-induced apoptosis in hepatocytes. TGF-β1-treated hepatocytes were exposed to low doses (0.5 and 1 μg/mL) and high dose (2 μg/mL) of melittin. The low doses significantly protected these cells from DNA damage in TGF-β1-induced apoptosis compared to the high dose. Also, melittin suppressed TGF-β1-induced apoptotic activation of the Bcl-2 family and caspase family of proteins, which resulted in the inhibition of poly-ADP-ribose polymerase (PARP) cleavage. These results demonstrate that TGF-β1 induces hepatocyte apoptosis and that an optimal dose of melittin exerts anti-apoptotic effects against TGF-β1-induced injury to hepatocytes via the mitochondrial pathway. These results suggest that an optimal dose of melittin can serve to protect cells against TGF-β1-mediated injury. - Highlights: → We investigated the anti-apoptotic effect of melittin on TGF-β1-induced hepatocyte. → TGF-β1 induces hepatocyte apoptosis. → TGF-β1-treated hepatocytes were exposed to low doses and high dose of melittin. → Optimal dose of melittin exerts anti-apoptotic effects to hepatocytes.

  4. Anti-Apoptotic Effects of Dapsone After Spinal Cord Injury in Rats.

    Science.gov (United States)

    Ríos, Camilo; Orozco-Suarez, Sandra; Salgado-Ceballos, Hermelinda; Mendez-Armenta, Marisela; Nava-Ruiz, Concepción; Santander, Iván; Barón-Flores, Veronica; Caram-Salas, Nadia; Diaz-Ruiz, Araceli

    2015-06-01

    Spinal cord injury (SCI) is a condition producing irreversible damage to the neurological function. Among the leading mechanisms associated to cell death after SCI, excitotoxicity, oxidative stress, inflammatory response and apoptosis are considered potential targets to prevent tissue damage. We recently reported that dapsone an anti-inflammatory drug, decreases the activity of myeloperoxidase, lipid peroxidation, improve neurological function and increase the amount of spared tissue after SCI in rats. In this study, we characterized the anti-apoptotic effect of dapsone administered at 12.5 mg/kg/24 h dose, starting at 3 and 5 h after SCI. We monitored the activity of caspases-8, 9, and 3 and quantitated Annexin V and TUNEL positive cells in the core of the lesion. Results showed increased activities of caspase-8, 9 and 3 at 72 h by SCI to reach increments of 69, 143 and 293 %, respectively, as compared to sham group. Meanwhile, dapsone, administered at 3 and 5 after SCI, reduced caspase-8 activity by 36 and 44 % respectively, whereas the activity of caspase-9 was diminished by 37 %. Likewise, the activity of caspase-3 showed a decrease of 38 %. Finally, both Annexin V and TUNEL-positive cells were significantly reduced by DDS as compared to untreated SCI animals. Results showed that dapsone exerted anti-apoptotic effect after SCI.

  5. Effect of ionizing radiation on hematopoietic stem cells and progenitor cells: Role of apoptosis and potential therapeutic significance of anti-apoptotic treatments; Effet des rayonnements ionisants sur les cellules souches et progeniteurs hematopoietiques : place de l'apoptose et interet therapeutique potentiel des traitements antiapoptotiques

    Energy Technology Data Exchange (ETDEWEB)

    Drouet, M.; Mourcin, F.; Grenier, N.; Mayol, J.F.; Leroux, V. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France); Sotto, J.J. [Inst. Albert Bonniot, La Tronche (France); Herodin, F. [Unite de Radiohematologie experimentale, Centre de Recherches du Service de Sante des Armees, La Tronche CEDEX (France)

    2002-07-01

    Bone marrow aplasia observed following ionizing radiation exposure (Total Body Irradiation; gamma dose range: 2-10 Gy) is a result, in particular, of the radiation-induced (RI) apoptosis in hematopoietic stem and progenitor cells (HSPC). We have previously shown in a baboon model of mobilized peripheral blood CD34{sup +} cell irradiation in vitro that RI apoptosis in HSPC was an early event, mostly occurring within the first 24 hours, which involves the CD95 Fas pathway. Apoptosis may be significantly reduced with a combination of 4 cytokines (4F): Stem Cell Factor (SCF), FLT-3 Ligand (FL), thrombopoietin (TPO), and interleukin-3 (IL-3), each at 50 ng{center_dot}mL{sup -1} (15% survival versus <3% untreated cells, 24 h post-irradiation at 2.5 Gy). In this study we show that addition of TNF-{alpha}(800 IU/ml) induces an increase in 4F efficacy in terms of cell survival 24 h after incubation (26% survival after 24 h irradiation exposure at 2.5 Gy) and amplification (k) of CD34{sup +} cells after 6 days in a serum free culture medium (SFM) (k{sub CD34{sup +}} = 4.3 and 6.3 respectively for 4F and successive 4F + TNF-{alpha}/4F treatments). In addition, the 4F combination allows culture on pre-established allogenic irradiated stromal cells in vitro at 4 Gy (k{sub CD34{sup +}} = 4.5). Overall this study suggests (i) the potential therapeutic interest for an early administration of anti-apoptotic cytokines with or without hematopoiesis inhibitors (emergency cytokine therapy) and (ii) the feasibility in the accidentally irradiated individual, of autologous cell therapy based on ex vivo expansion in order to perform autograft of residual HSPC collected after the accident. (author)

  6. Anti-apoptotic signaling and failure of apoptosis in the ischemic rat hippocampus

    DEFF Research Database (Denmark)

    Müller, Georg Johannes; Lassmann, Hans; Johansen, Flemming Fryd

    2007-01-01

    Several anti-apoptotic proteins are induced in CA1 neurons after transient forebrain ischemia (TFI), but fail to protect the majority of these cells from demise. Correlating cell death morphologies (apoptosis-like and necrosis-like death) with immunohistochemistry (IHC), we investigated whether...... anti-apoptosis contributes to survival, compromises apoptosis effector functions and/or delays death in CA1 neurons 1-7 days after TFI. As surrogate markers for bioenergetic failure, the IHC of respiratory chain complex (RCC) subunits was investigated. Dentate granule cell (DGC) apoptosis following...... colchicine injection severed as a reference for classical apoptosis. Heat shock protein 70 (Hsp70), neuronal apoptosis inhibitory protein (NAIP) and manganese superoxide dismutase (MnSOD) were upregulated in the majority of intact CA1 neurons paralleling the occurrence of CA1 neuronal death (days 3...

  7. PACAP has anti-apoptotic effect in the salivary gland of an invertebrate species, Helix pomatia.

    Science.gov (United States)

    Pirger, Zsolt; Nemeth, Jozsef; Hiripi, Laszlo; Toth, Gabor; Kiss, Peter; Lubics, Andrea; Tamas, Andrea; Hernadi, Laszlo; Kiss, Tibor; Reglodi, Dora

    2008-11-01

    Pituitary adenylate cyclase activating polypeptide (PACAP) shows a remarkable sequence similarity among species and several studies provide evidence that the functions of PACAP have also been conserved among vertebrate species. Relatively little is known about its presence and functions in invertebrates. The aim of the present study was to investigate whether the well-known anti-apoptotic effect of PACAP can also be demonstrated in invertebrates. This effect was studied in the salivary gland of a molluscan species, Helix pomatia. In this work, we first showed the presence of PACAP-like immunoreactivity in the Helix salivary gland by means of immunohistochemistry. Radioimmunoassay measurements showed that PACAP38-like immunoreactivity dominated in the salivary gland of both active and inactive snails and its concentration was higher in active than in inactive animals in contrast to PACAP27-like immunoreactivity, which did not show activity-dependent changes. PACAP induced a significant elevation of cAMP level in salivary gland extracts. Application of apoptosis-inducing agents, dopamine and colchicine, led to a marked increase in the number of terminal uridine deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive apoptotic cells in the salivary gland, which was significantly attenuated by PACAP treatment. In a similar manner, the number of caspase-positive cells was reduced after co-application of dopamine and PACAP. Taken together, the data indicate that PACAP activates cAMP in a molluscan species and we show, for the first time, that PACAP is anti-apoptotic in the invertebrate Helix pomatia.

  8. Anti-apoptotic effects of Curcuma longa L. extract and its curcuminoids against blue light-induced cytotoxicity in A2E-laden human retinal pigment epithelial cells.

    Science.gov (United States)

    Park, Sang-Il; Lee, Eun Hye; Kim, So Ra; Jang, Young Pyo

    2017-03-01

    The purpose of the study was to investigate the protective effect of the Curcuma longa L. extract (CLE) and its curcuminoids against blue light-induced cytotoxicity in human retinal pigment epithelial (RPE) cells laded with A2E. A2E has been concerned in age-related macular degeneration (AMD). To perform this study, A2E-accumulated ARPE-19 cells were exposed to blue light to induce cytotoxicity. The cytotoxicity and apoptotic gene expression levels were evaluated using a lactate dehydrogenase (LDH) assay and real-time PCR analysis, respectively. Curcuma longa L. extract was found to exert a protective effect in a dose-dependent manner. At a concentration of 15 μm, curcumin, demethoxycurcumin and bisdemethoxycurcumin exerted significant protective effects against blue light-induced cytotoxicity. Treatment with CLE and curcuminoids meaningfully reduced the mRNA levels of c-Abl and p53, which was known to be augmented in apoptotic RPE cells. Demethoxycurcumin and bisdemethoxycurcumin were found to inhibit p38 expression, which is increased in blue light-irradiated A2E-accumulated RPE cells. Curcuma longa L. extract and its curcuminoids provided significant protection against photooxidative damage and apoptosis in the RPE cells. Our results suggest that curcuminoids may show potential in the treatment of AMD. © 2017 Royal Pharmaceutical Society.

  9. Ethyl acetate extract of germinated brown rice attenuates hydrogen peroxide-induced oxidative stress in human SH-SY5Y neuroblastoma cells: role of anti-apoptotic, pro-survival and antioxidant genes.

    Science.gov (United States)

    Azmi, Nur Hanisah; Ismail, Norsharina; Imam, Mustapha Umar; Ismail, Maznah

    2013-07-17

    There are reports of improved metabolic outcomes due to consumption of germinated brown rice (GBR). Many of the functional effects of GBR can be linked to its high amounts of antioxidants. Interestingly, dietary components with high antioxidants have shown promise in the prevention of neurodegenerative diseases like Alzheimer's disease (AD). This effect of dietary components is mostly based on their ability to prevent apoptosis, which is believed to link oxidative damage to pathological changes in AD. In view of the rich antioxidant content of GBR, we studied its potential to modulate processes leading up to AD. The total phenolic content and antioxidant capacity of the ethyl acetate extract of GBR were compared to that of brown rice (BR), and the cytotoxicity of both extracts were determined on human SH-SY5Y neuronal cells using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) Assay. Based on its higher antioxidant potentials, the effect of the GBR extract on morphological changes due to hydrogen peroxide (H₂O₂)-induced oxidative damage in human SH-SY5Y neuronal cells was examined using inverted light microscope and fluorescence microscope by means of acridine orange-propidium iodide (AO/PI) staining. Also, evaluation of the transcriptional regulation of antioxidant and apoptotic genes was carried out using Multiplex Gene Expression System. The ethyl acetate extract of GBR had higher total phenolic content and antioxidant capacity compared to BR. The cytotoxicity results showed that GBR extract did not cause any damage to the human SH-SY5Y neuronal cells at concentrations of up to 20 ppm, and the morphological analyses showed that the GBR extract (up to 10 ppm) prevented H₂O₂-induced apoptotic changes in the cells. Furthermore, multiplex gene expression analyses showed that the protection of the cells by the GBR extract was linked to its ability to induce transcriptional changes in antioxidant (SOD 1, SOD 2 and catalase) and apoptotic

  10. Anti-apoptotic role of the sonic hedgehog signaling pathway in the proliferation of ameloblastoma.

    Science.gov (United States)

    Kanda, Shiori; Mitsuyasu, Takeshi; Nakao, Yu; Kawano, Shintaro; Goto, Yuichi; Matsubara, Ryota; Nakamura, Seiji

    2013-09-01

    Sonic hedgehog (SHH) signaling pathway is crucial to growth and patterning during organogenesis. Aberrant activation of the SHH signaling pathway can result in tumor formation. We examined the expression of SHH signaling molecules and investigated the involvement of the SHH pathway in the proliferation of ameloblastoma, the most common benign tumor of the jaws. We used immunohistochemistry on ameloblastoma specimens and immunocytochemistry and reverse transcription-PCR on the ameloblastoma cell line AM-1. We also used the inhibitors of SHH signaling, SHH neutralizing antibody and cyclopamine, to assess the effects of SHH on the proliferation of AM-1 cells. We detected expression of SHH, patched, GLI1, GLI2 and GLI3 in the ameloblastoma specimens and AM-1 cells. The proliferation of these cells was significantly inhibited in the presence of SHH neutralizing antibody or cyclopamine; this was confirmed by BrdU incorporation assays. Furthermore, in the presence of SHH neutralizing antibody, nuclear translocation of GLI1 and GLI2 was abolished, apoptosis was induced, BCL-2 expression decreased and BAX expression increased. Our results suggest that the SHH signaling pathway is constitutively active in ameloblastoma and plays an anti-apoptotic role in the proliferation of ameloblastoma cells through autocrine loop stimulation.

  11. Antiviral Properties of Chemical Inhibitors of Cellular Anti-Apoptotic Bcl-2 Proteins.

    Science.gov (United States)

    Bulanova, Daria; Ianevski, Aleksandr; Bugai, Andrii; Akimov, Yevhen; Kuivanen, Suvi; Paavilainen, Henrik; Kakkola, Laura; Nandania, Jatin; Turunen, Laura; Ohman, Tiina; Ala-Hongisto, Hanna; Pesonen, Hanna M; Kuisma, Marika S; Honkimaa, Anni; Walton, Emma L; Oksenych, Valentyn; Lorey, Martina B; Guschin, Dmitry; Shim, Jungmin; Kim, Jinhee; Than, Thoa T; Chang, So Young; Hukkanen, Veijo; Kulesskiy, Evgeny; Marjomaki, Varpu S; Julkunen, Ilkka; Nyman, Tuula A; Matikainen, Sampsa; Saarela, Jani S; Sane, Famara; Hober, Didier; Gabriel, Gülsah; De Brabander, Jef K; Martikainen, Miika; Windisch, Marc P; Min, Ji-Young; Bruzzone, Roberto; Aittokallio, Tero; Vähä-Koskela, Markus; Vapalahti, Olli; Pulk, Arto; Velagapudi, Vidya; Kainov, Denis E

    2017-09-25

    Viral diseases remain serious threats to public health because of the shortage of effective means of control. To combat the surge of viral diseases, new treatments are urgently needed. Here we show that small-molecules, which inhibit cellular anti-apoptotic Bcl-2 proteins (Bcl-2i), induced the premature death of cells infected with different RNA or DNA viruses, whereas, at the same concentrations, no toxicity was observed in mock-infected cells. Moreover, these compounds limited viral replication and spread. Surprisingly, Bcl-2i also induced the premature apoptosis of cells transfected with viral RNA or plasmid DNA but not of mock-transfected cells. These results suggest that Bcl-2i sensitizes cells containing foreign RNA or DNA to apoptosis. A comparison of the toxicity, antiviral activity, and side effects of six Bcl-2i allowed us to select A-1155463 as an antiviral lead candidate. Thus, our results pave the way for the further development of Bcl-2i for the prevention and treatment of viral diseases.

  12. Curcumin Anti-Apoptotic Action in a Model of Intestinal Epithelial Inflammatory Damage.

    Science.gov (United States)

    Loganes, Claudia; Lega, Sara; Bramuzzo, Matteo; Vecchi Brumatti, Liza; Piscianz, Elisa; Valencic, Erica; Tommasini, Alberto; Marcuzzi, Annalisa

    2017-06-06

    The purpose of this study is to determine if a preventive treatment with curcumin can protect intestinal epithelial cells from inflammatory damage induced by IFNγ. To achieve this goal we have used a human intestinal epithelial cell line (HT29) treated with IFNγ to undergo apoptotic changes that can reproduce the damage of intestinal epithelia exposed to inflammatory cytokines. In this model, we measured the effect of curcumin (curcuminoid from Curcuma Longa ) added as a pre-treatment at different time intervals before stimulation with IFNγ. Curcumin administration to HT29 culture before the inflammatory stimulus IFNγ reduced the cell apoptosis rate. This effect gradually declined with the reduction of the curcumin pre-incubation time. This anti-apoptotic action by curcumin pre-treatment was paralleled by a reduction of secreted IL7 in the HT29 culture media, while there was no relevant change in the other cytokine levels. Even though curcumin pre-administration did not impact the activation of the NF-κB pathway, a slight effect on the phosphorylation of proteins in this inflammatory signaling pathway was observed. In conclusion, curcumin pre-treatment can protect intestinal cells from inflammatory damage. These results can be the basis for studying the preventive role of curcumin in inflammatory bowel diseases.

  13. Molecular interactions of prodiginines with the BH3 domain of anti-apoptotic Bcl-2 family members.

    Directory of Open Access Journals (Sweden)

    Ali Hosseini

    Full Text Available Prodigiosin and obatoclax, members of the prodiginines family, are small molecules with anti-cancer properties that are currently under preclinical and clinical trials. The molecular target(s of these agents, however, is an open question. Combining experimental and computational techniques we find that prodigiosin binds to the BH3 domain in some BCL-2 protein families, which play an important role in the apoptotic programmed cell death. In particular, our results indicate a large affinity of prodigiosin for MCL-1, an anti-apoptotic member of the BCL-2 family. In melanoma cells, we demonstrate that prodigiosin activates the mitochondrial apoptotic pathway by disrupting MCL-1/BAK complexes. Computer simulations with the PELE software allow the description of the induced fit process, obtaining a detailed atomic view of the molecular interactions. These results provide new data to understand the mechanism of action of these molecules, and assist in the development of more specific inhibitors of anti-apoptotic BCL-2 proteins.

  14. The Anti-Apoptotic Properties of APEX1 in the Endothelium Require the First 20 Amino Acids and Converge on Thioredoxin-1.

    Science.gov (United States)

    Dyballa-Rukes, Nadine; Jakobs, Philipp; Eckers, Anna; Ale-Agha, Niloofar; Serbulea, Vlad; Aufenvenne, Karin; Zschauer, Tim-Christian; Rabanter, Lothar L; Jakob, Sascha; von Ameln, Florian; Eckermann, Olaf; Leitinger, Norbert; Goy, Christine; Altschmied, Joachim; Haendeler, Judith

    2017-04-20

    The APEX nuclease (multifunctional DNA repair enzyme) 1 (APEX1) has a disordered N-terminus, a redox, and a DNA repair domain. APEX1 has anti-apoptotic properties, which have been linked to both domains depending on cell type and experimental conditions. As protection against apoptosis is a hallmark of vessel integrity, we wanted to elucidate whether APEX1 acts anti-apoptotic in primary human endothelial cells and, if so, what the underlying mechanisms are. APEX1 inhibits apoptosis in endothelial cells by reducing Cathepsin D (CatD) cleavage, potentially by binding to the unprocessed form. Diminished CatD activation results in increased Thioredoxin-1 protein levels leading to reduced Caspase 3 activation. Consequently, apoptosis rates are decreased. This depends on the first twenty amino acids in APEX1, because APEX1 (21-318) induces CatD activity, decreases Thioredoxin-1 protein levels, and, thus, increases Caspase 3 activity and apoptosis. Along the same lines, APEX1 (1-20) inhibits Caspase 3 cleavage and apoptosis. Furthermore, re-expression of Thioredoxin-1 via lentiviral transduction rescues endothelial cells from APEX1 (21-318)-induced apoptosis. In an in vivo model of restenosis, which is characterized by oxidative stress, endothelial activation, and smooth muscle cell proliferation, Thioredoxin-1 protein levels are reduced in the endothelium of the carotids. APEX1 acts anti-apoptotic in endothelial cells. This anti-apoptotic effect depends on the first 20 amino acids of APEX1. As proper function of the endothelium during life span is a hallmark for individual health span, a detailed characterization of the functions of the APEX1N-terminus is required to understand all its cellular properties. Antioxid. Redox Signal. 26, 616-629.

  15. A functional yeast survival screen of tumor-derived cDNA libraries designed to identify anti-apoptotic mammalian oncogenes.

    Science.gov (United States)

    Eißmann, Moritz; Schwamb, Bettina; Melzer, Inga Maria; Moser, Julia; Siele, Dagmar; Köhl, Ulrike; Rieker, Ralf Joachim; Wachter, David Lukas; Agaimy, Abbas; Herpel, Esther; Baumgarten, Peter; Mittelbronn, Michel; Rakel, Stefanie; Kögel, Donat; Böhm, Stefanie; Gutschner, Tony; Diederichs, Sven; Zörnig, Martin

    2013-01-01

    Yeast cells can be killed upon expression of pro-apoptotic mammalian proteins. We have established a functional yeast survival screen that was used to isolate novel human anti-apoptotic genes overexpressed in treatment-resistant tumors. The screening of three different cDNA libraries prepared from metastatic melanoma, glioblastomas and leukemic blasts allowed for the identification of many yeast cell death-repressing cDNAs, including 28% of genes that are already known to inhibit apoptosis, 35% of genes upregulated in at least one tumor entity and 16% of genes described as both anti-apoptotic in function and upregulated in tumors. These results confirm the great potential of this screening tool to identify novel anti-apoptotic and tumor-relevant molecules. Three of the isolated candidate genes were further analyzed regarding their anti-apoptotic function in cell culture and their potential as a therapeutic target for molecular therapy. PAICS, an enzyme required for de novo purine biosynthesis, the long non-coding RNA MALAT1 and the MAST2 kinase are overexpressed in certain tumor entities and capable of suppressing apoptosis in human cells. Using a subcutaneous xenograft mouse model, we also demonstrated that glioblastoma tumor growth requires MAST2 expression. An additional advantage of the yeast survival screen is its universal applicability. By using various inducible pro-apoptotic killer proteins and screening the appropriate cDNA library prepared from normal or pathologic tissue of interest, the survival screen can be used to identify apoptosis inhibitors in many different systems.

  16. Anti-apoptotic effects of phyllanthin against alcohol- induced liver ...

    African Journals Online (AJOL)

    HepG2 cells alone and in co-culture with human monocytic (THP-1) differentiated macrophage cells. Methods: Cell viability was ... Results: Alcohol exposure significantly increased intracellular ROS generation (p < 0.001), decreased. MMP changes (p .... both cell types were cultured at a density of 3 x. 104 cells/well. Before ...

  17. Geno protective and anti-apoptotic effect of green tea against ...

    African Journals Online (AJOL)

    Geno protective and anti-apoptotic effect of green tea against perinatal lipopolysaccharide-exposure induced liver toxicity in rat newborns. Ahmed A. Allam, Sami A. Gabr, Jamaan Ajarem, Ahmad H. Alghadir, Revathi Sekar, Billy K.C. Chow ...

  18. Hypoglycemic and anti apoptotic effect of garlic in streptozotocin ...

    African Journals Online (AJOL)

    Diabetes mellitus is caused by many factor include oxidative stress that leads to apoptosis of beta cells of the pancreas and so the antioxidant therapy strongly correlated with decrease risk of diabetes mellitus. The aim of the present study was to investigate the efficacy of an aqueous extract of raw garlic in controlling serum ...

  19. Targeting the Anti-Apoptotic Protein c-FLIP for Cancer Therapy

    International Nuclear Information System (INIS)

    Safa, Ahmad R.; Pollok, Karen E.

    2011-01-01

    Cellular FLICE (FADD-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor and critical anti-apoptotic regulator that inhibits tumor necrosis factor-alpha (TNF-alpha), Fas-L, and TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis as well as chemotherapy-triggered apoptosis in malignant cells. c-FLIP is expressed as long (c-FLIP L ), short (c-FLIP S ), and c-FLIP R splice variants in human cells. c-FLIP binds to FADD and/or caspase-8 or -10 in a ligand-dependent and-independent fashion, which in turn prevents death-inducing signaling complex (DISC) formation and subsequent activation of the caspase cascade. Moreover, c-FLIP L and c-FLIP S are known to have multifunctional roles in various signaling pathways, as well as activating and/or upregulating several cytoprotective signaling molecules. Upregulation of c-FLIP has been found in various tumor types, and its downregulation has been shown to restore apoptosis triggered by cytokines and various chemotherapeutic agents. Hence, c-FLIP is an important target for cancer therapy. For example, small interfering RNAs (siRNAs) that specifically knockdown the expression of c-FLIP L in diverse human cancer cell lines augmented TRAIL-induced DISC recruitment and increased the efficacy of chemotherapeutic agents, thereby enhancing effector caspase stimulation and apoptosis. Moreover, small molecules causing degradation of c-FLIP as well as decreasing mRNA and protein levels of c-FLIP L and c-FLIP S splice variants have been found, and efforts are underway to develop other c-FLIP-targeted cancer therapies. This review focuses on (1) the functional role of c-FLIP splice variants in preventing apoptosis and inducing cytokine and drug resistance; (2) the molecular mechanisms that regulate c-FLIP expression; and (3) strategies to inhibit c-FLIP expression and function

  20. Targeting the Anti-Apoptotic Protein c-FLIP for Cancer Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Safa, Ahmad R., E-mail: asafa@iupui.edu [Department of Pharmacology and Toxicology, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Indiana University Simon Cancer Center, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Pollok, Karen E. [Department of Pharmacology and Toxicology, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Indiana University Simon Cancer Center, Indiana University School of Medicine, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States); Herman B. Wells Center for Pediatric Research, 980 W. Walnut Street, R3-C524, Indianapolis, IN 46202 (United States)

    2011-03-29

    Cellular FLICE (FADD-like IL-1beta-converting enzyme)-inhibitory protein (c-FLIP) is a major resistance factor and critical anti-apoptotic regulator that inhibits tumor necrosis factor-alpha (TNF-alpha), Fas-L, and TNF-related apoptosis-inducing ligand (TRAIL)-induced apoptosis as well as chemotherapy-triggered apoptosis in malignant cells. c-FLIP is expressed as long (c-FLIP{sub L}), short (c-FLIP{sub S}), and c-FLIP{sub R} splice variants in human cells. c-FLIP binds to FADD and/or caspase-8 or -10 in a ligand-dependent and-independent fashion, which in turn prevents death-inducing signaling complex (DISC) formation and subsequent activation of the caspase cascade. Moreover, c-FLIP{sub L} and c-FLIP{sub S} are known to have multifunctional roles in various signaling pathways, as well as activating and/or upregulating several cytoprotective signaling molecules. Upregulation of c-FLIP has been found in various tumor types, and its downregulation has been shown to restore apoptosis triggered by cytokines and various chemotherapeutic agents. Hence, c-FLIP is an important target for cancer therapy. For example, small interfering RNAs (siRNAs) that specifically knockdown the expression of c-FLIP{sub L} in diverse human cancer cell lines augmented TRAIL-induced DISC recruitment and increased the efficacy of chemotherapeutic agents, thereby enhancing effector caspase stimulation and apoptosis. Moreover, small molecules causing degradation of c-FLIP as well as decreasing mRNA and protein levels of c-FLIP{sub L} and c-FLIP{sub S} splice variants have been found, and efforts are underway to develop other c-FLIP-targeted cancer therapies. This review focuses on (1) the functional role of c-FLIP splice variants in preventing apoptosis and inducing cytokine and drug resistance; (2) the molecular mechanisms that regulate c-FLIP expression; and (3) strategies to inhibit c-FLIP expression and function.

  1. Rasagiline and selegiline suppress calcium efflux from mitochondria by PK11195-induced opening of mitochondrial permeability transition pore: a novel anti-apoptotic function for neuroprotection.

    Science.gov (United States)

    Wu, Yuqiu; Kazumura, Kimiko; Maruyama, Wakako; Osawa, Toshihiko; Naoi, Makoto

    2015-10-01

    Rasagiline and selegiline, inhibitors of type B monoamine oxidase (MAO-B), protect neurons from cell death in cellular and animal models. Suppression of mitochondrial membrane permeabilization and subsequent activation of apoptosis cascade, and induction of anti-apoptotic, pro-survival genes are proposed to contribute the anti-apoptotic function. Rasagiline suppresses neurotoxin- and oxidative stress-induced membrane permeabilization in isolated mitochondria, but the mechanism has been not fully clarified. In this paper, regulation of the mitochondrial permeability transition pore by rasagiline and selegiline was examined in apoptosis induced by PK11195, a ligand of the outer membrane translocator protein 18 kDa (TSPO) in SH-SY5Y cells. The pore opening was quantitatively measured using a simultaneous monitoring system for calcium (Ca(2+)) and superoxide (O2(-)) (Ishibashi et al. in Biochem Biophys Res Commun 344:571-580, 2006). The association of the pore opening with Ca(2+) efflux and ROS increase was proved by the inhibition of Bcl-2 overexpression and cyclosporine A treatment. Potency to release Ca(2+) was correlated with the cytotoxicity of TSPO antagonists, PK11195, FGIN-1-27 and protoporphyrin IX, whereas a TSPO agonist, 4-chloro-diazepamine, did not significantly increase Ca(2+) or cause cell death. Rasagiline and selegiline inhibited mitochondrial Ca(2+) efflux through the mitochondrial permeability transition pore dose dependently. Ca(2+) efflux was confirmed as the initial signal in mitochondrial apoptotic cascade, and the suppression of Ca(2+) efflux may account for the neuroprotective function of rasagiline and selegiline. The quantitative measurement of Ca(2+) efflux can be applied to determine anti-apoptotic activity of neuroprotective compounds. The role of mitochondrial Ca(2+) release in neuronal death and also in neuroprotection by MAO-B inhibitors is discussed.

  2. Epistatic mutations in PUMA BH3 drive an alternate binding mode to potently and selectively inhibit anti-apoptotic Bfl-1

    Energy Technology Data Exchange (ETDEWEB)

    Jenson, Justin M.; Ryan, Jeremy A.; Grant, Robert A.; Letai, Anthony; Keating, Amy E. (DFCI); (MIT)

    2017-06-08

    Overexpression of anti-apoptotic Bcl-2 family proteins contributes to cancer progression and confers resistance to chemotherapy. Small molecules that target Bcl-2 are used in the clinic to treat leukemia, but tight and selective inhibitors are not available for Bcl-2 paralog Bfl-1. Guided by computational analysis, we designed variants of the native BH3 motif PUMA that are > 150-fold selective for Bfl-1 binding. The designed peptides potently trigger disruption of the mitochondrial outer membrane in cells dependent on Bfl-1, but not in cells dependent on other anti-apoptotic homologs. High-resolution crystal structures show that designed peptide FS2 binds Bfl-1 in a shifted geometry, relative to PUMA and other binding partners, due to a set of epistatic mutations. FS2 modified with an electrophile reacts with a cysteine near the peptide-binding groove to augment specificity. Designed Bfl-1 binders provide reagents for cellular profiling and leads for developing enhanced and cell-permeable peptide or small-molecule inhibitors.

  3. Anti-apoptotic effects of tamarind leaves against ethanol-induced rat liver injury.

    Science.gov (United States)

    Ghoneim, Asser I; Eldahshan, Omayma A

    2012-03-01

    The leaf decoctions of Tamarindus indica (TI) have long been traditionally used in liver ailments. The aim of this study was to investigate the anti-apoptotic activity of TI leaf extract against acute ethanol (EtOH)-induced liver injury. The major constituents of the extract were also examined for standardization purposes. Rats (n = 5-7) were orally pretreated with TI leaf extract (25, 50 and 100 mg/kg) for seven days. Silymarin was used as a positive control. Liver tissue biochemical assays included key markers of apoptosis and its redox signalling. Serum enzyme levels were also determined. All graded doses of TI leaf extract mitigated the EtOH-induced liver caspase-3 activation (42, 57 and 64%) as well as DNA fragmentation (32, 47 and 50%), respectively. The highest dose of the extract demonstrated membrane-stabilizing (38%) in addition to glutathione-replenishing (88%) effects. Also, the leaves improved the liver histopathological alterations. Moreover, major plant bioactive polyphenolics, that might be responsible for the extract's observed effects, were isolated and identified. TI leaf extract demonstrated promising anti-apoptotic hepatoprotective effects in rats. The use of TI leaves in different liver diseases, having apoptosis as the underlying pathology, hence warrants further clinical investigation. © 2011 The Authors. JPP © 2011 Royal Pharmaceutical Society.

  4. Anti-Apoptotic and Pro-Survival Effect of Alpinate Oxyphyllae Fructus (AOF) in a d-Galactose-Induced Aging Heart.

    Science.gov (United States)

    Chang, Yung-Ming; Chang, Hen-Hong; Kuo, Wei-Wen; Lin, Hung-Jen; Yeh, Yu-Lan; Padma Viswanadha, Vijaya; Tsai, Chin-Chuan; Chen, Ray-Jade; Chang, Hsin-Nung; Huang, Chih-Yang

    2016-03-29

    Aging, a natural biological/physiological phenomenon, is accelerated by reactive oxygen species (ROS) accumulation and identified by a progressive decrease in physiological function. Several studies have shown a positive relationship between aging and chronic heart failure (HF). Cardiac apoptosis was found in age-related diseases. We used a traditional Chinese medicine, Alpinate Oxyphyllae Fructus (AOF), to evaluate its effect on cardiac anti-apoptosis and pro-survival. Male eight-week-old Sprague-Dawley (SD) rats were segregated into five groups: normal control group (NC), d-Galactose-Induced aging group (Aging), and AOF of 50 (AL (AOF low)), 100 (AM (AOF medium)), 150 (AH (AOF high)) mg/kg/day. After eight weeks, hearts were measured by an Hematoxylin-Eosin (H&E) stain, Terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-assays and Western blotting. The experimental results show that the cardiomyocyte apoptotic pathway protein expression increased in the d-Galactose-Induced aging groups, with dose-dependent inhibition in the AOF treatment group (AL, AM, and AH). Moreover, the expression of the pro-survival p-Akt (protein kinase B (Akt)), Bcl-2 (B-cell lymphoma 2), anti-apoptotic protein (Bcl-xL) protein decreased significantly in the d-Galactose-induced aging group, with increased performance in the AOF treatment group with levels of p-IGFIR and p-PI3K (Phosphatidylinositol-3' kinase (PI3K)) to increase by dosage and compensatory performance. On the other hand, the protein of the Sirtuin 1 (SIRT1) pathway expression decreased in the aging groups and showed improvement in the AOF treatment group. Our results suggest that AOF strongly works against ROS-induced aging heart problems.

  5. Anti-apoptotic effect of Shudipingchan granule in the substantia nigra of rat models of Parkinson′s disease

    Directory of Open Access Journals (Sweden)

    Qing Ye

    2016-01-01

    Full Text Available Levodopa is the gold-standard treatment for Parkinson′s disease. However, although it alleviates the clinical symptoms, it cannot delay the progressive apoptosis of dopaminergic neurons or prevent motor complications in the long term. In the present study, we investigated the effect of Shudipingchan granule on neuronal apoptosis in a rat model of Parkinson′s disease, established by injecting 6-hydroxydopamine into the substantia nigra pars compacta and ventral tegmental area. We then administered levodopa (20 mg/kg intraperitoneally, twice daily with or without Shudipingchan granule (7.5 mL/kg intragastrically, twice daily, for 4 weeks. The long-term use of levodopa accelerated apoptosis of nigral cells and worsened behavioral symptoms by activating the extracellular signal-regulated kinase pathway and downstream apoptotic factors. However, administration of Shudipingchan granule with levodopa reduced expression of phosphorylated extracellular signal-regulated kinase 1/2 and Bax, increased tyrosine hydroxylase and Bcl-2, reduced apoptosis in the substantia nigra, and markedly improved dyskinesia. These findings suggest that Shudipingchan granule suppresses neuronal apoptosis by inhibiting the hyperphosphorylation of extracellular signal-regulated kinase and downregulating expression of anti-apoptotic genes. Shudipingchan granule, used in combination with levodopa, can effectively reduce the symptoms of Parkinson′s disease.

  6. Piperphentonamine (PPTA) attenuated cerebral ischemia-induced memory deficits via neuroprotection associated with anti-apoptotic activity.

    Science.gov (United States)

    Bin, Juan; Wang, Qian; Zhuo, Ye-Ye; Xu, Jiang-Ping; Zhang, Han-Ting

    2012-12-01

    The calcium sensitizers levosimendan and piperphentonamine hydrochloride (PPTA) are used as cardiovascular drugs for treatment of heart failure. Given that levosimendan has been reported to exhibit a neuroprotective profile in a model of traumatic brain injury, it was interesting to know whether PPTA, a new calcium sensitizer recently developed in China, exerts a similar effect. The objective of this study was to determine whether PPTA exhibited neuroprotective effects and whether these properties were associated with memory. Four-vessel occlusion (4-VO) was used to induce global cerebral ischemia/reperfusion injury in rats treated with or without PPTA (5, 10 mg/kg, i.p., 2 h after the onset of reperfusion and then once a day for 15 consecutive days). Memory was measured using the step-through passive avoidance test. Neurochemical changes were examined in rat PC12 cells treated with oxygen-glucose deprivation (OGD) for 4 h followed by reoxygenation (OGD-R) for 24 h, in the absence or presence of PPTA. In vehicle-treated animals, 4-VO for 10 min produced memory deficits, as demonstrated by decreased retention in step-through passive avoidance, and massive neuron loss in the hippocampal CA1 subregion. These effects were attenuated by PPTA. The results were consistent with those observed in PC12 cells. PPTA treatment increased cell viability, as indicated by MTT assay, inhibited apoptosis, and decreased extracellular lactate dehydrogenase levels in Na(2)S(2)O(4)-treated PC12 cells. These results provide novel demonstration for the ability of PPTA to attenuate cerebral ischemia-induced memory deficits via neuroprotection in the hippocampus. The neuroprotective effect of PPTA appears to be associated with its anti-apoptotic activity. PPTA has the therapeutic potential for ischemic stroke.

  7. Targeting anti-apoptotic Bcl-2 by AT-101 to increase radiation efficacy: data from in vitro and clinical pharmacokinetic studies in head and neck cancer

    International Nuclear Information System (INIS)

    Zerp, Shuraila F.; Stoter, T. Rianne; Hoebers, Frank J. P.; Brekel, Michiel W. M. van den; Dubbelman, Ria; Kuipers, Gitta K.; Lafleur, M. Vincent M.; Slotman, Ben J.; Verheij, Marcel

    2015-01-01

    Pro-survival Bcl-2 family members can promote cancer development and contribute to treatment resistance. Head and neck squamous cell carcinoma (HNSCC) is frequently characterized by overexpression of anti-apoptotic Bcl-2 family members. Increased levels of these anti-apoptotic proteins have been associated with radio- and chemoresistance and poor clinical outcome. Inhibition of anti-apoptotic Bcl-2 family members therefore represents an appealing strategy to overcome resistance to anti-cancer therapies. The aim of this study was to evaluate combined effects of radiation and the pan-Bcl-2 inhibitor AT-101 in HNSCC in vitro. In addition, we determined human plasma levels of AT-101 obtained from a phase I/II trial, and compared these with the effective in vitro concentrations to substantiate therapeutic opportunities. We examined the effect of AT-101, radiation and the combination on apoptosis induction and clonogenic survival in two HNSCC cell lines that express the target proteins. Apoptosis was assessed by bis-benzimide staining to detect morphological nuclear changes and/or by propidium iodide staining and flow-cytometry analysis to quantify sub-diploid apoptotic nuclei. The type of interaction between AT-101 and radiation was evaluated by calculating the Combination Index (CI) and by performing isobolographic analysis. For the pharmacokinetic analysis, plasma AT-101 levels were measured by HPLC in blood samples collected from patients enrolled in our clinical phase I/II study. These patients with locally advanced HNSCC were treated with standard cisplatin-based chemoradiotherapy and received dose-escalating oral AT-101 in a 2-weeks daily schedule every 3 weeks. In vitro results showed that AT-101 enhances radiation-induced apoptosis with CI’s below 1.0, indicating synergy. This effect was sequence-dependent. Clonogenic survival assays demonstrated a radiosensitizing effect with a DEF 37 of 1.3 at sub-apoptotic concentrations of AT-101. Pharmacokinetic analysis

  8. Saponins from Panax japonicus attenuate D-galactose-induced cognitive impairment through its anti-oxidative and anti-apoptotic effects in rats.

    Science.gov (United States)

    Wang, Ting; Di, Guojie; Yang, Li; Dun, Yaoyan; Sun, Zhiwei; Wan, Jingzhi; Peng, Ben; Liu, Chaoqi; Xiong, Guangrun; Zhang, Changcheng; Yuan, Ding

    2015-09-01

    To investigate the neuroprotective effects of saponins from Panax japonicus (SPJ) on D-galactose (D-gal)-induced brain ageing, and further explore the underlying mechanisms. SPJ were analysed using high-pressure liquid chromatography. Male Wistar rats weighing 200 ± 20 g were randomly divided into four groups: control group (saline), D-gal-treated group (400 mg/kg, subcutaneously), D-gal + SPJ groups (50, 100 and 200 mg/kg, orally) and vitamin E group (100 mg/kg). Rats were injected corresponding drugs once daily for 8 weeks. Neuroprotective effects of SPJ were evaluated by Morris water maze, histopathological observations, biochemical assays, western blot analysis and quantitative real-time polymerase chain reaction (PCR) analysis in vivo as well as reactive oxygen species (ROS) measurement and apoptosis assay in vitro. Our present study showed that D-gal had a neurotoxic effect in rats and in SH-SY5Y cells due to oxidative stress induction, including decreased total anti-oxidant capacity, superoxide dismutase (SOD) and glutathione peroxidase activity, ultimately leading to spatial learning and memory impairment in rats and ROS accumulation in SH-SY5Y cells. SPJ improved spatial learning and memory deficits, attenuated hippocampus histopathological injury and restored impaired anti-oxidative as well as anti-apoptotic capacities in D-gal-induced ageing rats. In addition, SPJ remarkably decreased lipofuscin levels, increased hippocampus nuclear factor erythroid 2-related factor 2 (Nrf2) and silent mating type information regulation 2 homologue (SIRT1) protein levels and anti-oxidant genes expression such as manganese superoxide dismutase (Mn-SOD), heme oxygenase (HO-1), NAD(P)H quinone oxidoreductase 1 (NQO1) and cysteine ligase catalytic (GCLC) in D-gal-induced brain ageing. Our data suggested that D-gal induced multiple molecular and functional changes in brain similar to natural ageing process. SPJ protected brain from D-gal-induced neuronal

  9. The Putative Role of the Non-Gastric H+/K+-ATPase ATP12A (ATP1AL1 as Anti-Apoptotic Ion Transporter: Effect of the H+/K+ ATPase Inhibitor SCH28080 on Butyrate-Stimulated Myelomonocytic HL-60 Cells

    Directory of Open Access Journals (Sweden)

    Martin Jakab

    2014-10-01

    Full Text Available Background/Aims: The ATP12A gene codes for a non-gastric H+/K+ ATPase, which is expressed in a wide variety of tissues. The aim of this study was to test for the molecular and functional expression of the non-gastric H+/K+ ATPase ATP12A/ATP1AL1 in unstimulated and butyrate-stimulated (1 and 10 mM human myelomonocytic HL-60 cells, to unravel its potential role as putative apoptosis-counteracting ion transporter as well as to test for the effect of the H+/K+ ATPase inhibitor SCH28080 in apoptosis. Methods: Real-time reverse-transcription PCR (qRT-PCR was used for amplification and cloning of ATP12A transcripts and to assess transcriptional regulation. BCECF microfluorimetry was used to assess changes of intracellular pH (pHi after acute intracellular acid load (NH4Cl prepulsing. Mean cell volumes (MCV and MCV-recovery after osmotic cell shrinkage (Regulatory Volume Increase, RVI were assessed by Coulter counting. Flow-cytometry was used to measure MCV (Coulter principle, to assess apoptosis (phosphatidylserine exposure to the outer leaflet of the cell membrane, caspase activity, 7AAD staining and differentiation (CD86 expression. Results: We found by RT-PCR, intracellular pH measurements, MCV measurements and flow cytometry that ATP12A is expressed in human myelomonocytic HL-60 cells. Treatment of HL-60 cells with 1 mM butyrate leads to monocyte-directed differentiation whereas higher concentrations (10 mM induce apoptosis as assessed by flow-cytometric determination of CD86 expression, caspase activity, phosphatidylserine exposure on the outer leaflet of the cell membrane and MCV measurements. Transcriptional up-regulation of ATP12A and CD86 is evident in 1 mM butyrate-treated HL-60 cells. The H+/K+ ATPase inhibitor SCH28080 (100 µM diminishes K+-dependent pHi recovery after intracellular acid load and blocks RVI after osmotic cell shrinkage. After seeding, HL-60 cells increase their MCV within the first 24 h in culture, and subsequently

  10. Arctigenin Treatment Protects against Brain Damage through an Anti-Inflammatory and Anti-Apoptotic Mechanism after Needle Insertion

    Science.gov (United States)

    Song, Jie; Li, Na; Xia, Yang; Gao, Zhong; Zou, Sa-feng; Kong, Liang; Yao, Ying-Jia; Jiao, Ya-Nan; Yan, Yu-Hui; Li, Shao-Heng; Tao, Zhen-Yu; Lian, Guan; Yang, Jing-Xian; Kang, Ting-Guo

    2016-01-01

    neuroprotection of brain tissue through anti-inflammatory and anti-apoptotic effects in a mouse model of SWI. These results suggest a new strategy for promoting neuronal survival and function after CED to improve long-term patient outcome. PMID:27445818

  11. MicroRNA-197 Mediates the Overgrowth and Anti-Apoptotic Effects by Downregulating Insulin-Like Growth Factor-Binding Protein-3 During Nephroblastoma Tumorigenesis.

    Science.gov (United States)

    Hu, Jinhua; Liu, Guochang; Zhao, Zhang; Jia, Wei; Xia, Huimin

    2016-01-01

    MiR-197 is frequently upregulated to induce a series of oncogenic effects, which is closely associated with poor survival and prognosis of multiple malignancies. However, the roles of miR-197 in tumorigenesis and the detailed molecular mechanism in Wilms tumor (WT) have rarely been reported. This study aimed to evaluate the expression of miR-197 in WT in vivo and the potential effects of miR-197 on the proliferation and apoptosis in SK-NEP-1 cells. A total of 15 patients with a pathologically confirmed diagnosis of WT and 15 paraneoplastic controls were enrolled. Real-time quantitative PCR (RT-qPCR) identified the upregulation of miR-197 and downregulation of insulin-like growth factors binding protein 3 (IGFBP3) in WT tissues in comparison with adjacent normal tissue (p 197 caused a significantly reduced proliferation along with a dramatically enhanced apoptosis of SK-NEP-1 cells (p 197 mimics SK-NEP-1 cells and increased IGFBP3 expression with miR-197 inhibitor SK-NEP-1 cells compared with mock (p 197 and 3'-UTR site of IGFBP3. Overall, the above results indicated that miR-197 targeted IGFBP3 to induce the overgrowth and anti-apoptotic effects of WT cells, which could promote nephroblastoma tumorigenesis. Therefore, miR-197 may be further assessed as a potential target for the treatment of WT.

  12. Ginkgo biloba and Angelica archangelica bring back an impartial hepatic apoptotic to anti-apoptotic protein ratio after exposure to technetium 99mTc.

    Science.gov (United States)

    Raafat, Bassem M; Saleh, Ahmed; Shafaa, Medhat W; Khedr, Mahmoud; Ghafaar, Amany A

    2013-02-01

    The aim of this study was to study the effect of ionizing radiation on apoptosis-related protein concentrations as well as the radio-protective role of Ginkgo biloba and Angelica archangelica. The experiments were performed on 68 adult Wistar rats weighing 175 g (±10 g). Animals were subdivided into control group in which the animals received neither the protector nor the isotopes. The second group represents the animals that received 1 mCi of (99m)Tc only. The third group represents the animals that received A. archangelica for 7 days. The fourth group represents the animals that received G. biloba for 7 days. The fifth group represents the animals that received 1 mCi of (99m)Tc once after receiving A. archangelica for 7 days. The sixth group represents the animals that received mCi of (99m)Tc once after receiving G. biloba for 7 days. Radiation was administered as intravenous injection by 1 mCi of (99m)Tc with the legend methoxyisobutylisonitrile for 24 h. The concentration of p53, Bcl2 and malondialdehyde in liver as well as histopathological examination of liver cells were carried out. Results showed that apoptotic to anti-apoptotic protein ratio significantly (p archangelica and G. biloba in a dose based on the animal body weight. Electron microscope photographing supported this finding. It was concluded that both antioxidants can be used as radio-protective agents in cases of ionizing radiation exposure.

  13. Melatonin Promotes the In Vitro Development of Microinjected Pronuclear Mouse Embryos via Its Anti-Oxidative and Anti-Apoptotic Effects.

    Science.gov (United States)

    Tian, Xiuzhi; Wang, Feng; Zhang, Lu; Ji, Pengyun; Wang, Jing; Lv, Dongying; Li, Guangdong; Chai, Menglong; Lian, Zhengxing; Liu, Guoshi

    2017-05-05

    CRISPR/Cas9 (Clustered regularly interspaced short palindromic repeats) combined with pronuclear microinjection has become the most effective method for producing transgenic animals. However, the relatively low embryo developmental rate limits its application. In the current study, it was observed that 10 -7 M melatonin is considered an optimum concentration and significantly promoted the in vitro development of murine microinjected pronuclear embryos, as indicated by the increased blastocyst rate, hatching blastocyst rate and blastocyst cell number. When these blastocysts were implanted into recipient mice, the pregnancy rate and birth rate were significantly higher than those of the microinjected control, respectively. Mechanistic studies revealed that melatonin treatment reduced reactive oxygen species (ROS) production and cellular apoptosis during in vitro embryo development and improved the quality of the blastocysts. The implantation of quality-improved blastocysts led to elevated pregnancy and birth rates. In conclusion, the results revealed that the anti-oxidative and anti-apoptotic activities of melatonin improved the quality of microinjected pronuclear embryos and subsequently increased both the efficiency of embryo implantation and the birth rate of the pups. Therefore, the melatonin supplementation may provide a novel alternative method for generating large numbers of transgenic mice and this method can probably be used in human-assisted reproduction and genome editing.

  14. Candida albicans induces pro-inflammatory and anti-apoptotic signals in macrophages as revealed by quantitative proteomics and phosphoproteomics

    DEFF Research Database (Denmark)

    Reales-Calderón, Jose Antonio; Sylvester, Marc; Strijbis, Karin

    2013-01-01

    Macrophages play a pivotal role in the prevention of Candida albicans infections. Yeast recognition and phagocytosis by macrophages is mediated by Pattern Recognition Receptors (PRRs) that initiate downstream signal transduction cascades by protein phosphorylation and dephosphorylation. We exposed...... RAW 264.7 macrophages to C. albicans for 3h and used SILAC to quantify macrophage proteins and phosphoproteins by mass spectrometry to study the effects of infection. We identified 53 macrophage up-regulated proteins and 15 less abundant in the presence of C. albicans out of a total of 2071 identified...... of apoptotic markers revealed that anti-apoptotic signals prevailed during the interaction of the yeast. Our proteomics study suggests that besides inflammation, apoptosis is a central pathway in the immune defense against C. albicans infection....

  15. Anti-apoptotic and anti-oxidant effects of grape seed proanthocyanidin extract in preventing cyclosporine A-induced nephropathy.

    Science.gov (United States)

    Ulusoy, Sukru; Ozkan, Gulsum; Yucesan, Fulya Balaban; Ersöz, Şafak; Orem, Asim; Alkanat, Mehmet; Yuluğ, Esin; Kaynar, Kubra; Al, Sait

    2012-05-01

    Although the pathogenesis of cyclosporine (CsA) nephropathy is not completely understood, it is attributed to oxidative damage and apoptosis. Grape seed proanthocyanidin extract (GSPE) is a molecule with anti-oxidant and anti-apoptotic properties. Our aim was to demonstrate the effects of GSPE in preventing CsA nephropathy. Twenty-four Sprague-Dawley rats were divided into four groups. The control, GSPE, CsA and CsA+GSPE groups were given 1 mL olive oil, 100 mg/kg GSPE, 25 mg/kg CsA and 100 mg/kg GSPE+25 mg/kg CsA, respectively. On day 21, blood samples were taken for blood urea nitrogen (BUN), creatinine and CsA levels, and renal tissue was used for total oxidant system (TOS), total anti-oxidant system (TAS), oxidative stress index (OSI) and malondialdehyde (MDA) measurements. In addition to renal histopathology, apoptosis staining was performed on renal tissue. The BUN, creatinine, TOS, OSI, MDA, histopathological score, and apoptotic index exhibited increases in the CsA group. In the CsA+GSPE group, however, BUN, creatinine, OSI, MDA, renal histopathological score and apoptotic index (AI) decreased and TAS levels increased. In addition, there was no difference between the CsA and CsA+GSPE groups with regard to CsA levels. We demonstrated that GSPE prevents CsA nephropathy and that this effect is achieved by anti-apoptotic and anti-oxidant activity. We also achieved a significant recovery in kidney functions without affecting CsA plasma levels. © 2012 The Authors. Nephrology © 2012 Asian Pacific Society of Nephrology.

  16. Subcellular localization of CrmA : identification of a novel leucine-rich nuclear export signal conserved in anti-apoptotic serpins

    NARCIS (Netherlands)

    Rodriguez, JA; Span, SW; Kruyt, FAE; Giaccone, G

    2003-01-01

    The cowpox virus-encoded anti-apoptotic protein cytokine response modifier A (CrmA) is a member of the serpin family that specifically inhibits the cellular proteins caspase 1, caspase 8 and granzyme B. In this study, we have used Flag- and yellow fluorescent protein (YFP)-tagged versions of CrmA to

  17. Reconstitution of the anti-apoptotic Bcl-2 protein into lipid membranes and biophysical evidence for its detergent-driven association with the pro-apoptotic Bax protein.

    Directory of Open Access Journals (Sweden)

    Marcus Wallgren

    Full Text Available The anti-apoptotic B-cell CLL/lymphoma-2 (Bcl-2 protein and its counterpart, the pro-apoptotic Bcl-2-associated X protein (Bax, are key players in the regulation of the mitochondrial pathway of apoptosis. However, how they interact at the mitochondrial outer membrane (MOM and there determine whether the cell will live or be sentenced to death remains unknown. Competing models have been presented that describe how Bcl-2 inhibits the cell-killing activity of Bax, which is common in treatment-resistant tumors where Bcl-2 is overexpressed. Some studies suggest that Bcl-2 binds directly to and sequesters Bax, while others suggest an indirect process whereby Bcl-2 blocks BH3-only proteins and prevents them from activating Bax. Here we present the results of a biophysical study in which we investigated the putative interaction of solubilized full-length human Bcl-2 with Bax and the scope for incorporating the former into a native-like lipid environment. Far-UV circular dichroism (CD spectroscopy was used to detect direct Bcl-2-Bax-interactions in the presence of polyoxyethylene-(23-lauryl-ether (Brij-35 detergent at a level below its critical micelle concentration (CMC. Additional surface plasmon resonance (SPR measurements confirmed this observation and revealed a high affinity between the Bax and Bcl-2 proteins. Upon formation of this protein-protein complex, Bax also prevented the binding of antimycin A2 (a known inhibitory ligand of Bcl-2 to the Bcl-2 protein, as fluorescence spectroscopy experiments showed. In addition, Bcl-2 was able to form mixed micelles with Triton X-100 solubilized neutral phospholipids in the presence of high concentrations of Brij-35 (above its CMC. Following detergent removal, the integral membrane protein was found to have been fully reconstituted into a native-like membrane environment, as confirmed by ultracentrifugation and subsequent SDS-PAGE experiments.

  18. Wheatgrass-Derived Polysaccharide Has Antiinflammatory, Anti-Oxidative and Anti-Apoptotic Effects on LPS-Induced Hepatic Injury in Mice.

    Science.gov (United States)

    Nepali, Sarmila; Ki, Hyeon-Hui; Lee, Ji-Hyun; Lee, Hoon-Yeon; Kim, Dae-Ki; Lee, Young-Mi

    2017-07-01

    Hepatic injury occurs frequently during sepsis, and polysaccharides isolated from plants have been reported to have antiinflammatory and antioxidant effects in various models. However, the effect of wheatgrass-derived polysaccharide (WGP) has not been previously studied. In the present study, we investigated the effect of WGP on lipopolysaccharide (LPS)-induced hepatic injury in mice. Mice were pre-treated with WGP (100 or 200 mg/kg daily for 2 days) and then challenged with LPS (1 mg/kg, intraperitoneal), and sacrificed after 12 h. Wheatgrass-derived polysaccharide decreased serum aminotransferase levels and histological changes as compared with LPS-challenged mice. Wheatgrass-derived polysaccharide also significantly inhibited LPS-induced pro-inflammatory cytokine up-regulation and improved the oxidative status of liver tissues. Furthermore, these effects were found to be mediated by the suppression of the transcriptional activity of nuclear factor-kappa B (NF-κB), due to inhibitions of transforming growth factor beta (TGF-β)-activated kinase (TAK)-1 phosphorylation and inhibition of kappa B (IκB)-α degradation. In addition, WGP inhibited the activations of mitogen-activated protein kinases (MAPKs). Wheatgrass-derived polysaccharide also attenuated hepatic cell death by modulating caspase-3 and apoptosis associated mitochondrial proteins, such as, B-cell lymphoma 2 (Bcl-2) and Bcl-2-associated X (Bax). Taken together, WGP possesses antiinflammatory, anti-oxidant and anti-apoptotic activity and ameliorates LPS-induced liver injury in mice. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  19. Withaferin A Suppresses Anti-apoptotic BCL2, Bcl-xL, XIAP and ...

    African Journals Online (AJOL)

    The cells after WFA treatment were lysed in ice cold lysis buffer supplemented with protease inhibitors. The cell lysate was subjected to SDS-. PAGE separation. Proteins were transferred to polyvinyl idenedi fluoride (PVDF) membrane (GE. Healthcare, Freiburg, Germany) and then incubated with the primary antibodies. The.

  20. Withaferin A Suppresses Anti-apoptotic BCL2, Bcl-xL, XIAP and ...

    African Journals Online (AJOL)

    apoptotic genes, BCL2, Bcl-xL, XIAP and Survivin), in cervical carcinoma cells. Methods: Annexin V-FITC/propidium iodide (PI) staining was used for the investigation of cell apoptosis. RNA RNeasy Kits was used to isolate RNA and Omniscript ...

  1. Homologous recombination control by the anti-apoptotic onco-protein Bcl-2

    International Nuclear Information System (INIS)

    Dumay, A.

    2003-12-01

    This research thesis deals with the different biological mechanisms, notably the repair and apoptosis mechanisms induced by irradiation in cells. After a presentation of the genotoxic stress and DNA repair mechanisms, the author discusses the cellular response to a DNA double-strand break, and the regulation of these response mechanisms (how a cellular response emerges: life or death). The next part deals with the apoptosis (cell death by necrosis or apoptosis), and presents the BCL-2 protein family. Results are then reported on laboratory studies of the effect of this protein family

  2. Chemical Genetic Screens Identify Kinase Inhibitor Combinations that Target Anti-Apoptotic Proteins for Cancer Therapy.

    Science.gov (United States)

    Contreras, Jacob I; Robb, Caroline M; King, Hannah M; Baxter, Jared; Crawford, Ayrianne J; Kour, Smit; Kizhake, Smitha; Sonawane, Yogesh A; Rana, Sandeep; Hollingsworth, Michael A; Luo, Xu; Natarajan, Amarnath

    2018-04-05

    The study presented here provides a framework for the discovery of unique inhibitor combinations that target the apoptosis network for cancer therapy. A pair of doxycycline (Dox)-inducible cell lines that specifically report on the ability of an inhibitor to induce apoptosis by targeting either the Mcl-1 arm or the Bcl-2/Bcl-xL/Bcl-w arm were used. Cell-based assays were optimized for high throughput screening (HTS) with caspase 3/7 as a read out. HTS with a 355-member kinase inhibitor library and the panel of Dox-inducible cell lines revealed that cyclin dependent kinase (CDK) inhibitors induced apoptosis by targeting the Mcl-1 arm, whereas PI3K inhibitors induced apoptosis by targeting the Bcl-2/Bcl-xL/Bcl-w arm. Validation studies identified unique combinations that synergistically inhibited growth and induced apoptosis in a panel of cancer cell lines. Since these inhibitors have been or are currently in clinical trials as single agents, the combinations can be rapidly translated to the clinics.

  3. Peptide vaccination against multiple myeloma using peptides derived from anti-apoptotic proteins

    DEFF Research Database (Denmark)

    Jørgensen, Nicolai Grønne; Ahmad, Shamaila Munir; Abildgaard, Niels

    2016-01-01

    The B-cell lymphoma-2 (Bcl-2) family of proteins play a crucial role in multiple myeloma (MM), contributing to lacking apoptosis which is a hallmark of the disease. This makes the Bcl-2 proteins interesting targets for therapeutic peptide vaccination. We report a phase I trial of therapeutic...... vaccination with peptides from the proteins Bcl-2, Bcl-XL and Mcl-1 in patients with relapsed MM. Vaccines were given concomitant with bortezomib. Out of 7 enrolled patients, 4 received the full course of 8 vaccinations. The remaining 3 patients received fewer vaccinations due to progression, clinical...... decision of lacking effect and development of hypercalcemia, respectively. There were no signs of toxicity other than what was to be expected from bortezomib. Immune responses to the peptides were seen in all 6 patients receiving more than 2 vaccinations. Three patients had increased immune responses after...

  4. Nature's Solar Cell

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 2. Nature's Solar Cell. Stephen Suresh Gautham Nadig. Research News Volume 1 Issue 2 February 1996 pp 102-104. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/02/0102-0104 ...

  5. CCR9 interactions support ovarian cancer cell survival and resistance to cisplatin-induced apoptosis in a PI3K-dependent and FAK-independent fashion

    Directory of Open Access Journals (Sweden)

    Johnson Erica L

    2010-06-01

    Full Text Available Abstract Background Cisplatin is more often used to treat ovarian cancer (OvCa, which provides modest survival advantage primarily due to chemo-resistance and up regulated anti-apoptotic machineries in OvCa cells. Therefore, targeting the mechanisms responsible for cisplatin resistance in OvCa cell may improve therapeutic outcomes. We have shown that ovarian cancer cells express CC chemokine receptor-9 (CCR9. Others have also shown that CCL25, the only natural ligand for CCR9, up regulates anti-apoptotic proteins in immature T lymphocytes. Hence, it is plausible that CCR9-mediated cell signals might be involved in OvCa cell survival and inhibition of cisplatin-induced apoptosis. In this study, we investigated the potential role and molecular mechanisms of CCR9-mediated inhibition of cisplatin-induced apoptosis in OvCa cells. Methods Cell proliferation, vibrant apoptosis, and TUNEL assays were performed with or without cisplatin treatment in presence or absence of CCL25 to determine the role of the CCR9-CCL25 axis in cisplatin resistance. In situ Fast Activated cell-based ELISA (FACE assays were performed to determine anti-apoptotic signaling molecules responsible for CCL25-CCR9 mediated survival. Results Our results show interactions between CCR9 and CCL25 increased anti-apoptotic signaling cascades in OvCa cells, which rescued cells from cisplatin-induced cell death. Specifically, CCL25-CCR9 interactions mediated Akt, activation as well as GSK-3β and FKHR phosphorylation in a PI3K-dependent and FAK-independent fashion. Conclusions Our results suggest the CCR9-CCL25 axis plays an important role in reducing cisplatin-induced apoptosis of OvCa cells.

  6. The Protective Properties of the Strawberry (Fragaria ananassa) against Carbon Tetrachloride-Induced Hepatotoxicity in Rats Mediated by Anti-Apoptotic and Upregulation of Antioxidant Genes Expression Effects.

    Science.gov (United States)

    Hamed, Sherifa S; Al-Yhya, Nouf A; El-Khadragy, Manal F; Al-Olayan, Ebtesam M; Alajmi, Reem A; Hassan, Zeinab K; Hassan, Salwa B; Abdel Moneim, Ahmed E

    2016-01-01

    The strawberry (Fragaria ananassa) has been extensively used to treat a wide range of ailments in many cultures. The present study was aimed at evaluating the hepatoprotective effect of strawberry juice on experimentally induced liver injury in rats. To this end, rats were introperitoneally injected with carbon tetrachloride (CCl4) with or without strawberry juice supplementation for 12 weeks and the hepatoprotective effect of strawberry was assessed by measuring serum liver enzyme markers, hepatic tissue redox status and apoptotic markers with various techniques including biochemistry, ELISA, quantitative PCR assays and histochemistry. The hepatoprotective effect of the strawberry was evident by preventing CCl4-induced increase in liver enzymes levels. Determination of oxidative balance showed that strawberry treatment significantly blunted CCl4-induced increase in oxidative stress markers and decrease in enzymatic and non-enzymatic molecules in hepatic tissue. Furthermore, strawberry supplementation enhanced the anti-apoptotic protein, Bcl-2, and restrained the pro-apoptotic proteins Bax and caspase-3 with a marked reduction in collagen areas in hepatic tissue. These findings demonstrated that strawberry (F. ananassa) juice possessed antioxidant, anti-apoptotic and anti-fibrotic properties, probably mediated by the presence of polyphenols and flavonoids compounds.

  7. T-type Ca2+channels elicit pro-proliferative and anti-apoptotic responses through impaired PP2A/Akt1 signaling in PASMCs from patients with pulmonary arterial hypertension.

    Science.gov (United States)

    Sankhe, Safietou; Manousakidi, Sevasti; Antigny, Fabrice; Arthur Ataam, Jennifer; Bentebbal, Sana; Ruchon, Yann; Lecerf, Florence; Sabourin, Jessica; Price, Laura; Fadel, Elie; Dorfmüller, Peter; Eddahibi, Saadia; Humbert, Marc; Perros, Frédéric; Capuano, Véronique

    2017-10-01

    Idiopathic pulmonary arterial hypertension (iPAH) is characterized by obstructive hyperproliferation and apoptosis resistance of distal pulmonary artery smooth muscle cells (PASMCs). T-type Ca 2+ channel blockers have been shown to reduce experimental pulmonary hypertension, although the impact of T-type channel inhibition remains unexplored in PASMCs from iPAH patients. Here we show that T-type channels Cav3.1 and Cav3.2 are present in the lung and PASMCs from iPAH patients and control subjects. The blockade of T-type channels by the specific blocker, TTA-A2, prevents cell cycle progression and PASMCs growth. In iPAH cells, T-type channel signaling fails to activate phosphatase PP2A, leading to an increase in ERK1/2, P38 activation. Moreover, T-type channel signaling is redirected towards the activation of the kinase Akt1, leading to increased expression of the anti-apoptotic protein survivin, and a decrease in the pro-apoptotic mediator FoxO3A. Finally, in iPAH cells, Akt1 is no longer able to regulate caspase 9 activation, whereas T-type channel overexpression reverses PP2A defect in iPAH cells but reinforces the deleterious effects of Akt1 activation. Altogether, these data highlight T-type channel signaling as a strong trigger of the pathological phenotype of PASMCs from iPAH patients (hyper-proliferation/cells survival and apoptosis resistance), suggesting that both T-type channels and PP2A may be promising therapeutic targets for pulmonary hypertension. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Melatonin Promotes Brain-Derived Neurotrophic Factor (BDNF) Expression and Anti-Apoptotic Effects in Neonatal Hemolytic Hyperbilirubinemia via a Phospholipase (PLC)-Mediated Mechanism.

    Science.gov (United States)

    Luo, Yong; Peng, Mei; Wei, Hong

    2017-12-16

    BACKGROUND Melatonin therapy shows positive effects on neuroprotective factor brain-derived neurotrophic factor (BDNF) expression and neuronal apoptosis in neonatal hemolytic hyperbilirubinemia. We hypothesized that melatonin promotes BDNF expression and anti-apoptotic effects in neonatal hemolytic hyperbilirubinemia through a phospholipase (PLC)-mediated mechanism. MATERIAL AND METHODS A phenylhydrazine hydrochloride (PHZ)-induced neonatal hemolytic hyperbilirubinemia model was constructed in neonatal rats. Four experimental groups - a control group (n=30), a PHZ group (n=30), a PHZ + melatonin group (n=30), and a PHZ + melatonin+U73122 (a PLC inhibitor) group (n=30) - were constructed. Trunk blood was assayed for serum hemoglobin, hematocrit, total and direct bilirubin, BDNF, S100B, and tau protein levels. Brain tissue levels of neuronal apoptosis, BDNF expression, PLC activity, IP3 content, phospho- and total Ca2+/calmodulin-dependent protein kinase type IV (CaMKIV) expression, and phospho- and total cAMP response element binding protein (CREB) expression were also assayed. RESULTS PHZ-induced hemolytic hyperbilirubinemia was validated by significantly decreased serum hemoglobin and hematocrit as well as significantly increased total and direct serum bilirubin (p<0.05). Neonatal bilirubin-induced neurotoxicity was validated by significantly decreased serum BDNF, brain BDNF, and serum S100B, along with significantly increased serum tau protein (p<0.05). PHZ-induced hemolytic hyperbilirubinemia significantly decreased serum BDNF, brain BDNF, and PLC/IP3/Ca2+ pathway activation while increasing neuronal apoptosis levels (p<0.05), all of which were partially rescued by melatonin therapy (p<0.05). Pre-treatment with the PLC inhibitor U73122 largely abolished the positive effects of melatonin on PLC/IP3/Ca2+ pathway activation, downstream BDNF levels, and neuronal apoptosis (p<0.05). CONCLUSIONS Promotion of BDNF expression and anti-apoptotic effects in neonatal

  9. Natural killer cells in psoriasis.

    LENUS (Irish Health Repository)

    Tobin, A M

    2012-02-01

    Psoriasis is one of the most common immune-mediated disorders. There is evidence that it is mediated by Th1 and, more recently, Th17 cells. The cytokine pattern, particularly the dominance of TNF-alpha, implicates the innate immune system in psoriasis pathogenesis. Of the many components of the innate immune system known to be involved in psoriatic lesions, natural killer and natural killer T cells appear to have a unique role. We review the evidence supporting a role for natural killer cells in psoriasis.

  10. [Natural killer cells complot with dendritic cells].

    Science.gov (United States)

    Bielawska-Pohl, Aleksandra; Pajtasz-Piasecka, Elżbieta; Duś, Danuta

    2013-03-18

    Dendritic cells (DC) were initially considered as antigen presenting cells participating in the polarization of the immune response. Further understanding of their biology allowed determining their additional functions such as immunoregulatory and cytotoxicity. Until recently natural killer (NK) cells were known as a homogeneous population of lymphocytes capable of non-specific recognizing and eliminating target cells. Now it is widely accepted that NK cells, as a heterogeneous population, may also possess immunomodulatory functions. Moreover, the most recent analysis of the interactions between DC and NK cells revealed the exceptional functions of these cells. As a result of these studies the existence of bitypic cell population was postulated. The distinguishing features of these hybrid cells are: the expression of surface receptors typical for NK cells and DC, the cytotoxic activity, the production of interferons as well as their ability to present antigen after prior stimulation. Despite the lack of strong direct evidence that the same cell can be both cytotoxic and effectively present the antigen at the same time, there are experimental findings suggesting that generated ex vivo bitypic cells may be used in antitumor therapy. 

  11. Structural changes in the BH3 domain of SOUL protein upon interaction with the anti-apoptotic protein Bcl-xL.

    Science.gov (United States)

    Ambrosi, Emmanuele; Capaldi, Stefano; Bovi, Michele; Saccomani, Gianmaria; Perduca, Massimiliano; Monaco, Hugo L

    2011-09-01

    The SOUL protein is known to induce apoptosis by provoking the mitochondrial permeability transition, and a sequence homologous with the BH3 (Bcl-2 homology 3) domains has recently been identified in the protein, thus making it a potential new member of the BH3-only protein family. In the present study, we provide NMR, SPR (surface plasmon resonance) and crystallographic evidence that a peptide spanning residues 147-172 in SOUL interacts with the anti-apoptotic protein Bcl-xL. We have crystallized SOUL alone and the complex of its BH3 domain peptide with Bcl-xL, and solved their three-dimensional structures. The SOUL monomer is a single domain organized as a distorted β-barrel with eight anti-parallel strands and two α-helices. The BH3 domain extends across 15 residues at the end of the second helix and eight amino acids in the chain following it. There are important structural differences in the BH3 domain in the intact SOUL molecule and the same sequence bound to Bcl-xL.

  12. Genetic overexpressing of GPx-1 attenuates cocaine-induced renal toxicity via induction of anti-apoptotic factors.

    Science.gov (United States)

    Mai, Huynh Nhu; Jeong, Ji Hoon; Kim, Dae-Joong; Chung, Yoon Hee; Shin, Eun-Joo; Nguyen, Lan Thuy Ty; Nam, Yunsung; Lee, Yu Jeung; Cho, Eun-Hee; Nah, Seung-Yeol; Jang, Choon-Gon; Lei, Xin Gen; Kim, Hyoung-Chun

    2016-04-01

    The present study investigates the role of the glutathione peroxidase (GPx)-1 gene in cocaine-induced renal damage in mice. Multiple doses of cocaine increased lipid peroxidation, protein oxidation, and glutathione oxidation in the kidney of the non-transgenic mice (non-TG mice). The enzymatic activities of GPx and glutathione reductase were significantly decreased in non-TG mice, whereas superoxide dismutase was increased in the early phase of cocaine exposure. Treatment with cocaine resulted in significant decreases in expression of Bcl-2 and Bcl-xl in the kidney of non-TG mice, which resulted in significant increases in Bax and cleaved-caspase 3. Consistently, cocaine-induced tubular epithelial vacuolization and focal tubular necrosis were mainly observed in the proximal tubules in the kidneys of non-TG mice. These renal pathologic changes were much less pronounced in GPx-1 TG than in non-TG mice. These results suggest that the GPx-1 gene is a protective factor against nephrotoxicity induced by cocaine via interactive modulations between antioxidant and cell survival signaling processes. © 2016 John Wiley & Sons Australia, Ltd.

  13. Oxidative stress triggered by naturally occurring flavone apigenin results in senescence and chemotherapeutic effect in human colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Kacoli Banerjee

    2015-08-01

    Full Text Available Recent studies involving phytochemical polyphenolic compounds have suggested flavones often exert pro-oxidative effect in vitro against wide array of cancer cell lines. The aim of this study was to evaluate the in-vitro pro-oxidative activity of apigenin, a plant based flavone against colorectal cancer cell lines and investigate cumulative effect on long term exposure. In the present study, treatment of colorectal cell lines HT-29 and HCT-15 with apigenin resulted in anti-proliferative and apoptotic effects characterized by biochemical and morphological changes, including loss of mitochondrial membrane potential which aided in reversing the impaired apoptotic machinery leading to negative implications in cancer pathogenesis. Apigenin induces rapid free radical species production and the level of oxidative damage was assessed by qualitative and quantitative estimation of biochemical markers of oxidative stress. Increased level of mitochondrial superoxide suggested dose dependent mitochondrial oxidative damage which was generated by disruption in anti-apoptotic and pro-apoptotic protein balance. Continuous and persistent oxidative stress induced by apigenin at growth suppressive doses over extended treatment time period was observed to induce senescence which is a natural cellular mechanism to attenuate tumor formation. Senescence phenotype inducted by apigenin was attributed to changes in key molecules involved in p16-Rb and p53 independent p21 signaling pathways. Phosphorylation of retinoblastoma was inhibited and significant up-regulation of p21 led to simultaneous suppression of cyclins D1 and E which indicated the onset of senescence. Pro-oxidative stress induced premature senescence mediated by apigenin makes this treatment regimen a potential chemopreventive strategy and an in vitro model for aging research.

  14. Oxidative stress triggered by naturally occurring flavone apigenin results in senescence and chemotherapeutic effect in human colorectal cancer cells.

    Science.gov (United States)

    Banerjee, Kacoli; Mandal, Mahitosh

    2015-08-01

    Recent studies involving phytochemical polyphenolic compounds have suggested flavones often exert pro-oxidative effect in vitro against wide array of cancer cell lines. The aim of this study was to evaluate the in-vitro pro-oxidative activity of apigenin, a plant based flavone against colorectal cancer cell lines and investigate cumulative effect on long term exposure. In the present study, treatment of colorectal cell lines HT-29 and HCT-15 with apigenin resulted in anti-proliferative and apoptotic effects characterized by biochemical and morphological changes, including loss of mitochondrial membrane potential which aided in reversing the impaired apoptotic machinery leading to negative implications in cancer pathogenesis. Apigenin induces rapid free radical species production and the level of oxidative damage was assessed by qualitative and quantitative estimation of biochemical markers of oxidative stress. Increased level of mitochondrial superoxide suggested dose dependent mitochondrial oxidative damage which was generated by disruption in anti-apoptotic and pro-apoptotic protein balance. Continuous and persistent oxidative stress induced by apigenin at growth suppressive doses over extended treatment time period was observed to induce senescence which is a natural cellular mechanism to attenuate tumor formation. Senescence phenotype inducted by apigenin was attributed to changes in key molecules involved in p16-Rb and p53 independent p21 signaling pathways. Phosphorylation of retinoblastoma was inhibited and significant up-regulation of p21 led to simultaneous suppression of cyclins D1 and E which indicated the onset of senescence. Pro-oxidative stress induced premature senescence mediated by apigenin makes this treatment regimen a potential chemopreventive strategy and an in vitro model for aging research. Copyright © 2015 The Authors. Published by Elsevier B.V. All rights reserved.

  15. Prolonged hypoxic culture and trypsinization increase the pro-angiogenic potential of human adipose tissue-derived stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe Grøndahl; Frøbert, Ole; Pilgaard, Linda

    2011-01-01

    Transplantation of mesenchymal stromal cells (MSC), including adipose tissue-derived stem cells (ASC), is a promising option in the treatment of vascular disease. Short-term hypoxic culture of MSC augments secretion of anti-apoptotic and angiogenic cytokines. We hypothesized that prolonged hypoxic...... (1% and 5% oxygen) culture and trypsinization would augment ASC expression of anti-apoptotic and angiogenic cytokines and increase the angiogenic potential of ASC-conditioned media....

  16. Constitutive Activation of NF-kappaB in Prostate Carcinoma Cells Through a Positive Feedback Loop: Implication of Inducible IKK-Related Kinase (IKKi)

    National Research Council Canada - National Science Library

    Budunova, Irina V

    2004-01-01

    The overall goal of this project is to understand the role of inducible IKK-related kinase IKKi in constitutive activation of anti-apoptotic transcription factor NF-kB prostate carcinoma (PC) cells...

  17. The anti-apoptotic and cardioprotective effects of salvianolic acid a on rat cardiomyocytes following ischemia/reperfusion by DUSP-mediated regulation of the ERK1/2/JNK pathway.

    Directory of Open Access Journals (Sweden)

    Tongda Xu

    +I/R group. SAA exerts an anti-apoptotic role against myocardial IRI by inhibiting DUSP2-mediated JNK dephosphorylation and activating DUSP4/16-mediated ERK1/2 phosphorylation.

  18. Cypripedin, a phenanthrenequinone from Dendrobium densiflorum, sensitizes non-small cell lung cancer H460 cells to cisplatin-mediated apoptosis.

    Science.gov (United States)

    Wattanathamsan, Onsurang; Treesuwan, Surassawadee; Sritularak, Boonchoo; Pongrakhananon, Varisa

    2018-03-01

    The life-threatening potential of lung cancer has increased over the years due to its acquisition of chemotherapeutic resistance, especially to cisplatin, a first-line therapy. In response to this development, researchers have turned their attention to several compounds derived from natural origins, including cypripedin (CYP), a phenanthrenequinone substance extracted from Dendrobium densiflorum. The aim of the present study was to investigate the ability of CYP to induce apoptosis and enhance cisplatin-mediated death of human lung cancer NCI-H460 cells using cell viability and apoptosis assays. The induction of apoptosis by CYP was observed at a concentration of > 50 μM with the appearance of morphological changes, including DNA condensation and chromatin fragmentation. Together with, CYP was able to activate caspase-3 and downregulate the anti-apoptotic proteins Bcl-2 and Bcl-xL. Also, a non-cytotoxic dose of CYP synergistically potentiated the effect of cisplatin in non-small cell lung cancer line H460 cells, which clearly exhibited the apoptotic phenotype. Western blot analysis revealed that the underlying mechanism involved the downregulation of anti-apoptotic Bcl-xL, whereas the levels of other apoptotic regulatory proteins were not altered. This study provides interesting information on the potent effect of CYP as a chemotherapeutic sensitizer that could be further developed to improve the clinical outcomes of lung cancer patients.

  19. Viral Evasion of Natural Killer Cell Activation.

    Science.gov (United States)

    Ma, Yi; Li, Xiaojuan; Kuang, Ersheng

    2016-04-12

    Natural killer (NK) cells play a key role in antiviral innate defenses because of their abilities to kill infected cells and secrete regulatory cytokines. Additionally, NK cells exhibit adaptive memory-like antigen-specific responses, which represent a novel antiviral NK cell defense mechanism. Viruses have evolved various strategies to evade the recognition and destruction by NK cells through the downregulation of the NK cell activating receptors. Here, we review the recent findings on viral evasion of NK cells via the impairment of NK cell-activating receptors and ligands, which provide new insights on the relationship between NK cells and viral actions during persistent viral infections.

  20. Deficient natural killer cell function in preeclampsia

    Energy Technology Data Exchange (ETDEWEB)

    Alanen, A.; Lassila, O.

    1982-11-01

    Natural killer cell activity of peripheral blood lymphocytes was measured against K-562 target cells with a 4-hour /sup 51/Cr release assay in 15 primigravid women with preeclamptic symptoms. Nineteen primigravid women with an uncomplicated pregnancy and 18 nonpregnant women served as controls. The natural killer cell activity of preeclamptic women was observed to be significantly lower than that of both control groups. Natural killer cells in preeclamptic women responded normally to augmentation caused by interferon. These findings give further evidence for the participation of the maternal immune system in this pregnancy disorder.

  1. Natural Killer T Cells in Cancer Immunotherapy

    Science.gov (United States)

    Nair, Shiny; Dhodapkar, Madhav V.

    2017-01-01

    Natural killer T (NKT) cells are specialized CD1d-restricted T cells that recognize lipid antigens. Following stimulation, NKT cells lead to downstream activation of both innate and adaptive immune cells in the tumor microenvironment. This has impelled the development of NKT cell-targeted immunotherapies for treating cancer. In this review, we provide a brief overview of the stimulatory and regulatory functions of NKT cells in tumor immunity as well as highlight preclinical and clinical studies based on NKT cells. Finally, we discuss future perspectives to better harness the potential of NKT cells for cancer therapy. PMID:29018445

  2. Natural killer cells in chronic hepatitis B

    NARCIS (Netherlands)

    E.T.T.L. Tjwa (Eric)

    2012-01-01

    markdownabstract__Abstract__ Natural killer (NK) cells play a major role in anti-viral immunity as first line defense and regulation of virus-specific T cell responses. OBJECTIVE: To investigate phenotype and function of NK cells in patients with chronic hepatitis B virus (HBV) infection and

  3. Cordycepin, a Natural Antineoplastic Agent, Induces Apoptosis of Breast Cancer Cells via Caspase-dependent Pathways.

    Science.gov (United States)

    Wang, Di; Zhang, Yongfeng; Lu, Jiahui; Wang, Yang; Wang, Junyue; Meng, Qingfan; Lee, Robert J; Wang, Di; Teng, Lesheng

    2016-01-01

    Cordycepin, a major compound separated from Cordyceps sinensis, is known as a potential novel candidate for cancer therapy. Breast cancer, the most typical cancer diagnosed among women, remains a global health problem. In this study, the anti-breast cancer property of cordycepin and its underlying mechanisms was investigated. The direct effects of cordycepin on breast cancer cells both in in vitro and in vivo experiments were evaluated. Cordycepin exerted cytotoxicity in MCF-7 and MDA-MB-231 cells confirmed by reduced cell viability, inhibition of cell proliferation, enhanced lactate dehydrogenase release and reactive oxygen species accumulation, induced mitochondrial dysfunction and nuclear apoptosis in human breast cancer cells. Cordycepin increased the activation of pro-apoptotic proteins, including caspase-8, caspase-9, caspase-3 and Bax, and suppressed the expression of the anti-apoptotic protein, B-cell lymphoma 2 (Bcl-2). The inhibition on MCF-7-xenografted tumor growth in nude mice further confirmed cordycepin's anti-breast cancer effect. These aforementioned results reveal that cordycepin induces apoptosis in human breast cancer cells via caspase-dependent pathways. The data shed light on the possibility of cordycepin being a safe agent for breast cancer treatment.

  4. A natural product-like JAK2/STAT3 inhibitor induces apoptosis of malignant melanoma cells.

    Directory of Open Access Journals (Sweden)

    Ke-Jia Wu

    Full Text Available The JAK2/STAT3 signaling pathway plays a critical role in tumorigenesis, and has been suggested as a potential molecular target for anti-melanoma therapeutics. However, few JAK2 inhibitors were being tested for melanoma therapy. In this study, eight amentoflavone analogues were evaluated for their activity against human malignant melanoma cells. The most potent analogue, compound 1, inhibited the phosphorylation of JAK2 and STAT3 in human melanoma cells, but had no discernible effect on total JAK2 and STAT3 levels. A cellular thermal shift assay was performed to identify that JAK2 is engaged by 1 in cell lysates. Moreover, compound 1 showed higher antiproliferative activity against human melanoma A375 cells compared to a panel of cancer and normal cell lines. Compound 1 also activated caspase-3 and cleaved PARP, which are markers of apoptosis, and suppressed the anti-apoptotic Bcl-2 level. Finally, compound 1 induced apoptosis in 80% of treated melanoma cells. To our knowledge, compound 1 is the first amentoflavone-based JAK2 inhibitor to be investigated for use as an anti-melanoma agent.

  5. Leveraging natural killer cells for cancer immunotherapy.

    Science.gov (United States)

    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.

  6. Characteristics of Yorkshire swine natural killer cells

    International Nuclear Information System (INIS)

    Ferguson, F.G.; Botticelli, G.; Confer, F.L.; Pinto, A.J.

    1986-01-01

    Since natural killer (NK) cells have a role in immune surveillance, they are important to consider in disease pathogenesis and resistance. We examined cell aspects responsible for NK cell mediated cytotoxicity in Yorkshire swine. Using cell separation procedures, peripheral blood lymphocytes were examined for reactivity to a panel of tumor targets, kinetics of lysis, morphology, surface receptor characteristics and response to immunoregulators. YAC-1 lymphoma and K-562 myeloid leukemia cells were sensitive to swine NK cells; whereas, several other tumor lines were not. In kinetic studies, swine NK cells were slower in initiation of the lytic process than cells responsible for NK activity in other species; small agranular lymphocytes are responsible for this activity in swine. These cells were examined for the presence of a surface marker, asialo GM1, which is common to NK cells in several other species. Swine NK cells respond to an interferon inducer, poly I:C, with enhanced NK activity. Cells in Yorkshire swine have characteristics which are unique but also have characteristics common to NK cells in other species

  7. Herceptin-Resistance and Overexpression of Anti-Apoptotic Molecule Bci-XL: A Potential Strategy for Overcoming Resistance to Herceptin

    National Research Council Canada - National Science Library

    Xu, Liang

    2005-01-01

    ...-(+) breast cancer cells to Herceptin. (-)-gossypol showed potent anti-tumor activity to human breast cancer cell lines with high levels of Bcl-xL but has only minimal effect on human normal breast epithelial cells with low Bcl-xL...

  8. Cytomegalovirus evasion of natural killer cell responses.

    Science.gov (United States)

    Farrell, H E; Degli-Esposti, M A; Davis-Poynter, N J

    1999-04-01

    Natural killer (NK) cells are an important component of the innate cellular immune system. They are particularly important during the early immune responses following virus infection, prior to the induction of cytotoxic T cells (CTL). Unlike CTL, which recognize specific peptides displayed on the surface of cells by class I MHC, NK cells respond to aberrant expression of cell surface molecules, in particular class I MHC, in a non-specific manner. Thus, cells expressing low levels of surface class I MHC are susceptible to recognition by NK cells, with concomitant triggering of cytolytic and cytokine-mediated responses. Many viruses, including the cytomegaloviruses, downregulate cell surface MHC class I: this is likely to provide protection against CTL-mediated clearance of infected cells, but may also render infected cells sensitive to NK-cell attack. This review focuses upon cytomegalovirus-encoded proteins that are believed to promote evasion of NK-cell-mediated immunity. The class I MHC homologues, encoded by all cytomegaloviruses characterised to date, have been implicated as molecular 'decoys', which may mimic the ability of cellular MHC class I to inhibit NK-cell functions. Results from studies in vitro are not uniform, but in general they support the proposal that the class I homologues engage inhibitory receptors from NK cells and other cell types that normally interact with cellular class I. Consistent with this, in vivo studies of murine cytomegalovirus indicate that the class I homologue is required for efficient evasion of NK-cell-mediated clearance. Recently a second murine cytomegalovirus protein, a C-C chemokine homologue, has been implicated as promoting evasion of NK and T-cell-mediated clearance in vivo.

  9. Anti-apoptotic ARC protein confers chemoresistance by controlling leukemia-microenvironment interactions through a NFκB/IL1β signaling network

    KAUST Repository

    Carter, Bing Z.

    2016-04-11

    To better understand how the apoptosis repressor with caspase recruitment domain (ARC) protein confers drug resistance in acute myeloid leukemia (AML), we investigated the role of ARC in regulating leukemia-mesenchymal stromal cell (MSC) interactions. In addition to the previously reported effect on AML apoptosis, we have demonstrated that ARC enhances migration and adhesion of leukemia cells to MSCs both in vitro and in a novel human extramedullary bone/bone marrow mouse model. Mechanistic studies revealed that ARC induces IL1β expression in AML cells and increases CCL2, CCL4, and CXCL12 expression in MSCs, both through ARC-mediated activation of NFκB. Expression of these chemokines in MSCs increased by AML cells in an ARC/IL1β-dependent manner; likewise, IL1β expression was elevated when leukemia cells were co-cultured with MSCs. Further, cells from AML patients expressed the receptors for and migrated toward CCL2, CCL4, and CXCL12. Inhibition of IL1β suppressed AML cell migration and sensitized the cells co-cultured with MSCs to chemotherapy. Our results suggest the existence of a complex ARC-regulated circuit that maintains intimate connection of AML with the tumor microenvironment through NFκB/IL1β-regulated chemokine receptor/ligand axes and reciprocal crosstalk resulting in cytoprotection. The data implicate ARC as a promising drug target to potentially sensitize AML cells to chemotherapy.

  10. Neutrophils Induced Licensing of Natural Killer Cells

    Directory of Open Access Journals (Sweden)

    Keishiro Amano

    2015-01-01

    Full Text Available Natural killer (NK cells acquire effector function through a licensing process and exert anti-leukemia/tumor effect. However, there is no means to promote a licensing effect of allogeneic NK cells other than cytomegalovirus reactivation-induced licensing in allogeneic hematopoietic stem cell transplantation in human. In mice, a licensing process is mediated by Ly49 receptors which recognize self-major histocompatibility complex class I. The distribution of four Ly49 receptors showed similar pattern in congenic mice, B10, B10.BR, and B10.D2, which have B10 background. Forty Gy-irradiated 2×106 B10.D2 cells including splenocytes, peripheral blood mononuclear cells in untreated mice, or granulocyte colony-stimulating factor treated mice were injected intraperitoneally into B10 mice. We found that murine NK cells were effectively licensed by intraperitoneal injection of donor neutrophils with its corresponding NK receptor ligand in B10 mice as a recipient and B10.D2 as a donor. Mechanistic studies revealed that NK cells showed the upregulation of intracellular interferon-γ and CD107a expression as markers of NK cell activation. Moreover, enriched neutrophils enhanced licensing effect of NK cells; meanwhile, licensing effect was diminished by depletion of neutrophils. Collectively, injection of neutrophils induced NK cell licensing (activation via NK receptor ligand interaction.

  11. Angelica sinensis Exerts Angiogenic and Anti-apoptotic Effects Against Cerebral Ischemia-Reperfusion Injury by Activating p38MAPK/HIF-1[Formula: see text]/VEGF-A Signaling in Rats.

    Science.gov (United States)

    Cheng, Chin-Yi; Ho, Tin-Yun; Hsiang, Chien-Yun; Tang, Nou-Ying; Hsieh, Ching-Liang; Kao, Shung-Te; Lee, Yu-Chen

    2017-01-01

    This study evaluated the effects of Angelica sinensis extract [Dang Gui (DG)] administered before 60[Formula: see text]min of middle cerebral artery occlusion followed by 3[Formula: see text]d of reperfusion and investigated the involvement of mitogen-activated protein kinase (MAPK)/hypoxia-inducible factor (HIF)-1[Formula: see text] signaling in the cortical ischemic penumbra. DG was intraperitoneally administered at a dose of 0.25[Formula: see text]g/kg (DG-0.25g), 0.5[Formula: see text]g/kg (DG-0.5g), or 1[Formula: see text]g/kg (DG-1g) 30[Formula: see text]min before the onset of cerebral ischemia. Our study results revealed that DG-0.5g and DG-1g pretreatment effectively attenuated cerebral infarct and improved neurological deficits. DG-0.5g and DG-1g pretreatment significantly downregulated glial fibrillary acidic protein (GFAP), cytochrome c, and cleaved caspase-3 expression and upregulated phospho-p38 MAPK (p-p38 MAPK)/p38 MAPK, phospho-cAMP response element-binding protein (p-CREB)/CREB, cytosolic and mitochondrial phospho-Bad (p-Bad)/Bad ratios, and HIF-1[Formula: see text], vascular endothelial growth factor-A (VEGF-A), phospho-90 kDa ribosomal S6 kinase (p-p90RSK), and von Willebrand factor (vWF) expression in the cortical ischemic penumbra. Pretreatment with SB203580, a p38 MAPK inhibitor, dramatically abrogated the upregulating effects of DG-1g on p-p38 MAPK/p38 MAPK, p-CREB/CREB, and p-Bad/Bad ratios and HIF-1[Formula: see text], VEGF-A, and vWF expression and the downregulating effects of DG-1g on GFAP, cytochrome c, cleaved caspase-3, and cerebral infarction. DG-0.5g and DG-1g pretreatment provided neuroprotective effects against astrocyte-mediated cerebral infarction by activating angiogenic and anti-apoptotic signaling. Moreover, the angiogenic and anti-apoptotic effects of DG pretreatment can be attributed to the activation of p38 MAPK/HIF-1[Formula: see text]/VEGF-A/vWF signaling and p38 MAPK/HIF-1[Formula: see text

  12. A functional microRNA library screen reveals miR-410 as a novel anti-apoptotic regulator of cholangiocarcinoma

    International Nuclear Information System (INIS)

    Palumbo, Tiziana; Poultsides, George A.; Kouraklis, Grigorios; Liakakos, Theodore; Drakaki, Alexandra; Peros, George; Hatziapostolou, Maria; Iliopoulos, Dimitrios

    2016-01-01

    Cholangiocarcinoma is characterized by late diagnosis and a poor survival rate. MicroRNAs have been involved in the pathogenesis of different cancer types, including cholangiocarcinoma. Our aim was to identify novel microRNAs regulating cholangiocarcinoma cell growth in vitro and in vivo. A functional microRNA library screen was performed in human cholangiocarcinoma cells to identify microRNAs that regulate cholangiocarcinoma cell growth. Real-time PCR analysis evaluated miR-9 and XIAP mRNA levels in cholangiocarcinoma cells and tumors. The screen identified 21 microRNAs that regulated >50 % cholangiocarcinoma cell growth. MiR-410 was identified as the top suppressor of growth, while its overexpression significantly inhibited the invasion and colony formation ability of cholangiocarcinoma cells. Bioinformatics analysis revealed that microRNA-410 exerts its effects through the direct regulation of the X-linked inhibitor of apoptosis protein (XIAP). Furthermore, overexpression of miR-410 significantly reduced cholangiocarcinoma tumor growth in a xenograft mouse model through induction of apoptosis. In addition, we identified an inverse relationship between miR-410 and XIAP mRNA levels in human cholangiocarcinomas. Taken together, our study revealed a novel microRNA signaling pathway involved in cholangiocarcinoma and suggests that manipulation of the miR-410/XIAP pathway could have a therapeutic potential for cholangiocarcinoma. The online version of this article (doi:10.1186/s12885-016-2384-0) contains supplementary material, which is available to authorized users

  13. Cytokine regulation of pro- and anti-apoptotic genes in rat hepatocytes: NF-kappaB-regulated inhibitor of apoptosis protein 2 (cIAP2) prevents apoptosis

    NARCIS (Netherlands)

    Schoemaker, Marieke H.; Ros, Jenny E.; Homan, Manon; Trautwein, Christian; Liston, Peter; Poelstra, Klaas; van Goor, Harry; Jansen, Peter L. M.; Moshage, Han

    2002-01-01

    BACKGROUND/AIMS: In acute liver failure, hepatocytes are exposed to various cytokines that activate both cell survival and apoptotic pathways. NF-kappaB is a central transcription factor in these responses. Recent studies indicate that blocking NF-kappaB causes apoptosis, indicating the existence of

  14. Unraveling Natural Killer T-Cells Development

    Directory of Open Access Journals (Sweden)

    Sabrina Bianca Bennstein

    2018-01-01

    Full Text Available Natural killer T-cells are a subset of innate-like T-cells with the ability to bridge innate and adaptive immunity. There is great interest in harnessing these cells to improve tumor therapy; however, greater understanding of invariant NKT (iNKT cell biology is needed. The first step is to learn more about NKT development within the thymus. Recent studies suggest lineage separation of murine iNKT cells into iNKT1, iNKT2, and iNKT17 cells instead of shared developmental stages. This review will focus on these new studies and will discuss the evidence for lineage separation in contrast to shared developmental stages. The author will also highlight the classifications of murine iNKT cells according to identified transcription factors and cytokine production, and will discuss transcriptional and posttranscriptional regulations, and the role of mammalian target of rapamycin. Finally, the importance of these findings for human cancer therapy will be briefly discussed.

  15. Natural killer cells complot with dendritic cells 

    Directory of Open Access Journals (Sweden)

    Aleksandra Bielawska-Pohl

    2013-03-01

    Full Text Available Dendritic cells (DC were initially considered as antigen presenting cells participating in the polarization of the immune response. Further understanding of their biology allowed determining their additional functions such as immunoregulatory and cytotoxicity. Until recently natural killer (NK cells were known as a homogeneous population of lymphocytes capable of non-specific recognizing and eliminating target cells. Now it is widely accepted that NK cells, as a heterogeneous population, may also possess immunomodulatory functions. Moreover, the most recent analysis of the interactions between DC and NK cells revealed the exceptional functions of these cells. As a result of these studies the existence of bitypic cell population was postulated. The distinguishing features of these hybrid cells are: the expression of surface receptors typical for NK cells and DC, the cytotoxic activity, the production of interferons as well as their ability to present antigen after prior stimulation. Despite the lack of strong direct evidence that the same cell can be both cytotoxic and effectively present the antigen at the same time, there are experimental findings suggesting that generated ex vivo bitypic cells may be used in antitumor therapy. 

  16. Antioxidant, anti-inflammatory, anti-apoptotic, and skin regenerative properties of an Aloe vera-based extract of Nerium oleander leaves (NAE-8®

    Directory of Open Access Journals (Sweden)

    Benson KF

    2015-05-01

    Full Text Available Kathleen F Benson,1 Robert A Newman,2,3 Gitte S Jensen1 1NIS Labs, Klamath Falls, Oregon, USA; 2University of Texas MD Anderson Cancer Center, Houston, TX, USA; 3Nerium Biotechnology, Inc, San Antonio, TX, USA Objective: The goal for this study was to evaluate the effects of an Aloe vera-based Nerium oleander extract (NAE-8®, compared to an extract of A. vera gel alone (ALOE, and to an aqueous extract of N. oleander (AQ-NOE in bioassays pertaining to dermatologic potential with respect to antioxidant protection, anti-inflammatory effects, and cytokine profiles in vitro. Methods: Cellular antioxidant protection was evaluated in three separate bioassays: The cellular antioxidant protection of erythrocytes (CAP-e assay, protection of cellular viability and prevention of apoptosis, and protection of intracellular reduced glutathione levels, where the last two assays were performed using human primary dermal fibroblasts. Reduction of intracellular formation of reactive oxygen species (ROS was tested using polymorphonuclear cells in the absence and presence of oxidative stress. Changes to cytokine and chemokine profiles when whole blood cells and human primary dermal fibroblasts were exposed to test products were determined using a 40-plex Luminex array as a method for exploring the potential cross-talk between circulating and skin-resident cells. Results: The NAE-8® provided significantly better antioxidant protection in the CAP-e bioassay than AQ-NOE. NAE-8® and AQ-NOE both protected cellular viability and intracellular reduced glutathione, and reduced the ROS formation significantly when compared to control cells, both under inflamed and neutral culture conditions. ALOE showed minimal effect in these bioassays. In contrast to the NAE-8®, the AQ-NOE showed induction of inflammation in the whole blood cultures, as evidenced by the high induction of CD69 expression and secretion of a number of inflammatory cytokines. The treatment of dermal

  17. Molecular Alliance of Lymantria dispar Multiple Nucleopolyhedrovirus and a Short Unmodified Antisense Oligonucleotide of Its Anti-Apoptotic IAP-3 Gene: A Novel Approach for Gypsy Moth Control.

    Science.gov (United States)

    Oberemok, Volodymyr V; Laikova, Kateryna V; Zaitsev, Aleksei S; Shumskykh, Maksym N; Kasich, Igor N; Gal'chinsky, Nikita V; Bekirova, Viktoriya V; Makarov, Valentin V; Agranovsky, Alexey A; Gushchin, Vladimir A; Zubarev, Ilya V; Kubyshkin, Anatoly V; Fomochkina, Iryna I; Gorlov, Mikhail V; Skorokhod, Oleksii A

    2017-11-17

    Baculovirus IAP (inhibitor-of-apoptosis) genes originated by capture of host genes. Unmodified short antisense DNA oligonucleotides (oligoDNAs) from baculovirus IAP genes can down-regulate specific gene expression profiles in both baculovirus-free and baculovirus-infected insects. In this study, gypsy moth ( Lymantria dispar ) larvae infected with multiple nucleopolyhedrovirus (LdMNPV), and LdMNPV-free larvae, were treated with oligoDNA antisense to the RING (really interesting new gene) domain of the LdMNPV IAP-3 gene. The results with respect to insect mortality, biomass accumulation, histological studies, RT-PCR, and analysis of DNA apoptotic fragmentation suggest that oligoRING induced increased apoptotic processes in both LdMNPV-free and LdMNPV-infected insect cells, but were more pronounced in the latter. These data open up possibilities for promising new routes of insect pest control using antisense phosphodiester DNA oligonucleotides.

  18. Molecular Alliance of Lymantria dispar Multiple Nucleopolyhedrovirus and a Short Unmodified Antisense Oligonucleotide of Its Anti-Apoptotic IAP-3 Gene: A Novel Approach for Gypsy Moth Control

    Directory of Open Access Journals (Sweden)

    Volodymyr V. Oberemok

    2017-11-01

    Full Text Available Baculovirus IAP (inhibitor-of-apoptosis genes originated by capture of host genes. Unmodified short antisense DNA oligonucleotides (oligoDNAs from baculovirus IAP genes can down-regulate specific gene expression profiles in both baculovirus-free and baculovirus-infected insects. In this study, gypsy moth (Lymantria dispar larvae infected with multiple nucleopolyhedrovirus (LdMNPV, and LdMNPV-free larvae, were treated with oligoDNA antisense to the RING (really interesting new gene domain of the LdMNPV IAP-3 gene. The results with respect to insect mortality, biomass accumulation, histological studies, RT-PCR, and analysis of DNA apoptotic fragmentation suggest that oligoRING induced increased apoptotic processes in both LdMNPV-free and LdMNPV-infected insect cells, but were more pronounced in the latter. These data open up possibilities for promising new routes of insect pest control using antisense phosphodiester DNA oligonucleotides.

  19. Polydatin attenuates d-galactose-induced liver and brain damage through its anti-oxidative, anti-inflammatory and anti-apoptotic effects in mice.

    Science.gov (United States)

    Xu, Lie-Qiang; Xie, You-Liang; Gui, Shu-Hua; Zhang, Xie; Mo, Zhi-Zhun; Sun, Chao-Yue; Li, Cai-Lan; Luo, Dan-Dan; Zhang, Zhen-Biao; Su, Zi-Ren; Xie, Jian-Hui

    2016-11-09

    Accumulating evidence has shown that chronic injection of d-galactose (d-gal) can mimic natural aging, with accompanying liver and brain injury. Oxidative stress and apoptosis play a vital role in the aging process. In this study, the antioxidant ability of polydatin (PD) was investigated using four established in vitro systems. An in vivo study was also conducted to investigate the possible protective effect of PD on d-gal-induced liver and brain damage. The results showed that PD had remarkable in vitro free radical scavenging activity on 2,2-diphenyl-1-picryl-hydrazyl (DPPH˙), 2,2'-azino-bis(3-ethylbenzo-thiazoline-6-sulfonic acid) (ABTS + ˙) radical ions, and hydroxyl and superoxide anions. Results in vivo indicated that, in a group treated with d-gal plus PD, PD remarkably decreased the depression of body weight and organ indexes, reduced the levels of the serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), and alleviated alterations in liver and brain histopathology. PD also significantly decreased the level of MDA and elevated SOD, GSH-Px, CAT activity and T-AOC levels in the liver and brain. In addition, the levels of inflammatory mediators, such as TNF-α, IL-1β and IL-6 in serum were markedly reduced after PD treatment. Western blotting results revealed that PD treatment noticeably attenuated the d-gal-induced elevation of Bcl-2/Bax ratio and caspase-3 protein expression in liver and brain. Overall, our findings indicate that PD treatment could effectively attenuate d-gal-induced liver and brain damage, and the mechanism might be associated with decreasing the oxidative stress, inflammation and apoptosis caused by d-gal. PD holds good potential for further development into a promising pharmaceutical candidate for the treatment of age-associated diseases.

  20. [Myeloid/natural killer cell precursor and myeloid/natural killer cell acute leukemia].

    Science.gov (United States)

    Ni, Ming; Chen, Bao-An

    2014-04-01

    With the popularity of flow cytometry, the classification of leukemia become more detailed. Myeloid/natural killer cell precursor acute leukemia and myeloid/natural killer cell acute leukemias are generally recognized as two kinds of rare leukemias and have poor prognosis. The cells expressed both myeloid and lymphatic antigens in these two leukemia and can not be diagnosed by morphology. The only basis to make a definite diagnosis is their unique Immunophenotyping. The role of CD7 and CD56 in these two leukemia are compelling, in the other hand, as the progress of cell differentiation research, there are many new awareness of NK cell differentiation. In this article, the biological origin, clinical manifestation, diagnosis, treatment and the role of CD7 and CD56 in these two leukemia are briefly summarized.

  1. Natural killer cells enhance the immune surveillance of cancer

    African Journals Online (AJOL)

    Faisal Nouroz

    2015-09-11

    Sep 11, 2015 ... is carried out to treat cancer [6]. 3. Role of Natural killer cells. Natural killer (NK) cells were first discovered in humans and mice in 1975 and are large granular population of leukocytes, that can directly kill the virus infected or tumor cells [4]. NK cells of the immune system specially lyse the tumor cells and.

  2. Natural killer T cells in lipoprotein metabolism and atherosclerosis

    OpenAIRE

    Getz, Godfrey S; VanderLaan, Paul A; Reardon, Catherine A

    2011-01-01

    Cells of both the innate and adaptive immune system participate in the development of atherosclerosis, a chronic inflammatory disorder of medium and large arteries. Natural killer T (NKT) cells express surface markers characteristic of natural killer cells and conventional T cells and bridge the innate and adaptive immune systems. The development and activation of NKT cells is dependent upon CD1d, a MHC-class I-type molecule that presents lipids, especially glycolipids to the TCR on NKT cells...

  3. Prolonged hypoxic culture and trypsinization increase the pro-angiogenic potential of human adipose tissue-derived stem cells

    DEFF Research Database (Denmark)

    Rasmussen, Jeppe Grøndahl; Frøbert, Ole; Pilgaard, Linda

    2011-01-01

    Transplantation of mesenchymal stromal cells (MSC), including adipose tissue-derived stem cells (ASC), is a promising option in the treatment of vascular disease. Short-term hypoxic culture of MSC augments secretion of anti-apoptotic and angiogenic cytokines. We hypothesized that prolonged hypoxic...

  4. The effects of insulin pre-administration in mice exposed to ethanol: alleviating hepatic oxidative injury through anti-oxidative, anti-apoptotic activities and deteriorating hepatic steatosis through SRBEP-1c activation.

    Science.gov (United States)

    Liu, Jiangzheng; Wang, Xin; Peng, Zhengwu; Zhang, Tao; Wu, Hao; Yu, Weihua; Kong, Deqing; Liu, Ying; Bai, Hua; Liu, Rui; Zhang, Xiaodi; Hai, Chunxu

    2015-01-01

    -administration deteriorated hepatic steatosis in mice exposed to ethanol might be through SRBEP-1c activation. In summary, these results indicated that insulin pre-administration effectively alleviated liver oxidative injury through anti-inflammatory, anti-oxidative and anti-apoptotic activities but also deteriorated hepatic steatosis through SRBEP-1c activation in mice exposed to ethanol. Our study provided novel insight about the effects and mechanisms of insulin on ethanol-induced liver injury.

  5. Review: Natural killer cells enhance the immune surveillance of ...

    African Journals Online (AJOL)

    All the cells of the immune system cooperatively work against infectious agents and cancerous cells but Natural killer (NK) cells are playing an important role to respond to tumor by enhancing the expression of complementary domain (CD86) on dendritic cells (DCs) and production of IL-12. NK cells demolished tumor ...

  6. CytotoxicEffect of Curcumin on Proliferation of HT_29 Cell Line

    Directory of Open Access Journals (Sweden)

    Mohamad Nabiuni

    2017-10-01

    Conclusion:According to molecular mechanisms of cell proliferation and curcumin ability in the induction of pro_apoptotic proteins and the inhibition of anti_apoptotic proteins as well as inhibition of as survival pathways,like NF_KB and AKT, this predisposition makes curcumin a good anticancer drug.

  7. Synthetic Biology: A Bridge between Artificial and Natural Cells

    Science.gov (United States)

    Ding, Yunfeng; Wu, Fan; Tan, Cheemeng

    2014-01-01

    Artificial cells are simple cell-like entities that possess certain properties of natural cells. In general, artificial cells are constructed using three parts: (1) biological membranes that serve as protective barriers, while allowing communication between the cells and the environment; (2) transcription and translation machinery that synthesize proteins based on genetic sequences; and (3) genetic modules that control the dynamics of the whole cell. Artificial cells are minimal and well-defined systems that can be more easily engineered and controlled when compared to natural cells. Artificial cells can be used as biomimetic systems to study and understand natural dynamics of cells with minimal interference from cellular complexity. However, there remain significant gaps between artificial and natural cells. How much information can we encode into artificial cells? What is the minimal number of factors that are necessary to achieve robust functioning of artificial cells? Can artificial cells communicate with their environments efficiently? Can artificial cells replicate, divide or even evolve? Here, we review synthetic biological methods that could shrink the gaps between artificial and natural cells. The closure of these gaps will lead to advancement in synthetic biology, cellular biology and biomedical applications. PMID:25532531

  8. Lactobacilli Differentially Activate Natural Killer Cells

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    bacteria on regulatory functions of NK-cells. Here, we have investigated how human gut flora-derived non-pathogenic lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human peripheral blood NK cells upon bacterial stimulation. CD3-CD56+ NK cells were isolated from...... having engulfed bacteria, stimulated the growth of the NK cells. In contrast, a Lactobacillus paracasei strain caused the NK cells to proliferate only in the presence of monocytes. These results demonstrate that various lactobacilli have the capacity to activate NK cells in vitro, in a monocyte dependent...

  9. A Natural Triterpene Derivative from Euphorbia kansui Inhibits Cell Proliferation and Induces Apoptosis against Rat Intestinal Epithelioid Cell Line in Vitro

    Directory of Open Access Journals (Sweden)

    Fangfang Cheng

    2015-08-01

    Full Text Available Kansenone is a triterpene from the root of the traditional Chinese medicine, Euphorbia kansui. However, kansenone exerts serious toxicity, but the exact mechanism was not clear. In this work, the effects of kansenone on cell proliferation, cell cycle, cell damage, and cell apoptosis were investigated. The suppression of cell proliferation was assessed via the colorimetric MTT assay, and cell morphology was visualized via inverted microscopy after IEC-6 cells were incubated with different concentrations of kansenone. Reactive oxygen species (ROS, superoxide dismutase (SOD and malondialdehyde (MDA content were detected for evaluating cell damage. RNase/propidium iodide (PI labeling for evaluation of cell cycle distribution was performed by flow cytometry analysis. Annexin V-fluorescein isothiocyanate (FITC/PI and Hoechst 33342/Annexin V-FITC/PI staining assay for cell apoptosis detection were performed using confocal laser scanning microscopy and high content screening. Moreover, apoptosis induction was further confirmed by transmission electron microscope (TEM and JC-1 mitochondrial membrane potential, western blot and RT-PCR analysis. The results demonstrated that kansenone exerted high cytotoxicity, induced cell arrest at G0/G1 phase, and caused mitochondria damage. In addition, kansenone could up-regulate the apoptotic proteins Bax, AIF, Apaf-1, cytochrome c, caspase-3, caspase-9, caspase-8, FasR, FasL, NF-κB, and TNFR1 mRNA expression levels, and down-regulate the anti-apoptotic Bcl-2 family proteins, revealing that kansenone induces apoptosis through both the death receptor and mitochondrial pathways.

  10. A natural compound from Hydnophytum formicarium induces apoptosis of MCF-7 cells via up-regulation of Bax

    Directory of Open Access Journals (Sweden)

    Hohmann Judit

    2010-05-01

    Full Text Available Abstract Background Hydnophytum formicarium Jack is an epyphytic shrub that belongs to the family of Rubiaceae and is native to the tropical rain forests of the Asean region, which includes Malaysia. A flavanoid derivative, 7, 3', 5'-trihydroxyflavanone (3HFD, isolated from H. formicarium has been reported to have cytotoxic effects on the human breast carcinoma cell line MCF-7. The aim of the current study was to investigate the mode of cell death in MCF-7 cells treated with 3HFD. A DNA fragmentation assay was conducted on isolated genomic DNA, a TUNEL assay was used to determine the mode of cell death and Western blotting was used to evaluate the expression levels of Bax and Bcl-2. Immunofluorescence staining of MCF-7 cells was also performed to confirm the up-regulation of the Bax protein. Results The ladder pattern resulting from the DNA fragmentation assay was a multimer of 180 kb. The morphological changes of cells undergoing apoptosis were visualised by a TUNEL assay over time. The percentage of apoptotic cells increased as early as 6 hours post treatment compared to untreated cells. Western blotting revealed up-regulation of the pro-apoptotic protein Bax. However, 3HFD did not affect expression of the anti-apoptotic protein Bcl-2. Conclusions Our results provide evidence that plant-derived 3HFD was able to induce the apoptotic cell death of MCF-7 cells by increasing Bax expression level and makes 3HFD a promising agent for chemotherapy, which merits further study.

  11. Regulation of Murine Natural Killer Cell Commitment

    Directory of Open Access Journals (Sweden)

    Nicholas D Huntington

    2013-01-01

    Full Text Available NK cells can derive from the same precursors as B and T cells, however to achieve lineage specificity, several transcription factors need to be activated or annulled. While a few important transcription factors have identified for NK genesis the mechanisms of how this is achieved is far from resolved. Adding to the complexity of this, NK cells are found and potentially develop in diverse locations in vivo and it remains to be addressed if a common NK cell precursor seeds diverse niches and how transcription factors may differentially regulate NK cell commitment in distinct microenvironments. Here we will summarise some recent findings in NK cell commitment and discuss how a NK cell transcriptional network might be organised, while addressing some misconceptions and anomalies along the way.

  12. Interaction of DNA-lesions induced by sodium fluoride and radiation and its influence in apoptotic induction in cancer cell lines

    Directory of Open Access Journals (Sweden)

    Santosh Podder

    2015-01-01

    Full Text Available Fluoride is an essential trace element but also an environmental contaminant with major sources of exposure being drinking water, food and pesticides. Previous studies showed that sodium fluoride (NaF at 5 mM or more is required to induce apoptosis and chromosome aberrations and proposed that DNA damage and apoptosis play an important role in toxicity of excessive fluoride. The aim of this study is directed to understand the nature of DNA-lesions induced by NaF by allowing its interaction with radiation induced DNA-lesions. NaF 5 mM was used after observing inability to induce DNA damages and apoptosis by single exposure with 50 μM or 1 mM NaF. Co-exposure to NaF and radiation significantly increased the frequency of aberrant metaphases and exchange aberrations in human lymphocytes and arrested the cells in G1 stage instead of apoptotic death. Flow cytometric analysis, DNA fragmentation and PARP-cleavage analysis clearly indicated that 5 mM NaF together with radiation (1 Gy induced apoptosis in both U87 and K562 cells due to down regulation of expression of anti-apoptotic proteins, like Bcl2 in U87 and inhibitors of apoptotic proteins like survivin and cIAP in K562 cells. This study herein suggested that single exposure with extremely low concentration of NaF unable to induce DNA lesions whereas higher concentration induced DNA lesions interact with the radiation-induced DNA lesions. Both are probably repaired rapidly thus showed increased interactive effect. Coexposure to NaF and radiation induces more apoptosis in cancer cell lines which could be due to increased exchange aberrations through lesions interaction and downregulating anti-apoptotic genes.

  13. The Natural History of Sickle Cell Disease

    Science.gov (United States)

    Serjeant, Graham R.

    2013-01-01

    The term sickle cell disease embraces a group of genetic conditions in which pathology results from the inheritance of the sickle cell gene either homozygously or as a double heterozygote with another interacting gene. The spectrum of resulting conditions is therefore influenced by the geography of individual hemoglobin genes, but in most populations, the commonest genotype at birth is homozygous sickle cell (SS) disease. Because this genotype generally manifests a greater mortality, the relative proportion of sickle cell genotypes is influenced by age as well as the geographical distribution of individual genes. PMID:23813607

  14. Transplantation and innate immunity: the lesson of natural killer cells

    Directory of Open Access Journals (Sweden)

    Moretta Lorenzo

    2009-12-01

    Full Text Available Abstract Natural killer cells have been demonstrated to play a major role in mediating an anti-leukemia effect in patients given a T-cell depleted allogeneic hematopoietic stem cell transplantation from an HLA-haploidentical family donor. In particular, donor-derived natural killer cells, which are alloreactive (i.e. KIR/HLA mismatched towards recipient cells, significantly contribute to the eradication of leukemia blasts escaping the preparative regimen to transplantation. A recent study on high-risk pediatric acute lymphoblastic leukemia refractory to chemotherapy further highlighted the importance of donors with alloreactive natural killer cells in haploidentical hematopoietic stem cell transplantation, as it demonstrated that these cells can emerge starting from the fourth-fifth month after the allograft and persist for many months. This study represents a major breakthrough in the cure of otherwise fatal leukemias, providing information on the best criteria for choosing the optimal donor.

  15. Andrographolide - A promising therapeutic agent, negatively regulates glial cell derived neurodegeneration of prefrontal cortex, hippocampus and working memory impairment.

    Science.gov (United States)

    Das, Sudeshna; Mishra, K P; Ganju, Lilly; Singh, S B

    2017-12-15

    Over activation of glial cell derived innate immune factors induces neuro-inflammation that results in neurodegenerative disease, like working memory impairment. In this study, we have investigated the role of andrographolide, a major constituent of Andrographis paniculata plant, in reduction of reactive glial cell derived working memory impairment. Real time PCR, Western bloting, flow cytometric and immunofluorescence studies demonstrated that andrographolide inhibited lipopolysaccharide (LPS)-induced overexpression of HMGB1, TLR4, NFκB, COX-2, iNOS, and release of inflammatory mediators in primary mix glial culture, adult mice prefrontal cortex and hippocampus region. Active microglial and reactive astrocytic makers were also downregulated after andrographolide treatment. Andrographolide suppressed overexpression of microglial MIP-1α, P2X7 receptor and its downstream signaling mediators including-inflammasome NLRP3, caspase1 and mature IL-1β. Furthermore, in vivo maze studies suggested that andrographolide treatment reversed LPS-induced behavioural and working memory disturbances including regulation of expression of protein markers like PKC, p-CREB, amyloid beta, APP, p-tau, synapsin and PSD-95. Andrographolide, by lowering expression of pro apoptotic genes and enhancing the expression of anti-apoptotic gene showed its anti-apoptotic nature that in turn reduces neurodegeneration. Morphology studies using Nissl and FJB staining also showed the neuroprotective effect of andrographolide in the prefrontal cortex region. The above studies indicated that andrographolide prevented neuroinflammation-associated neurodegeneration and improved synaptic plasticity markers in cortical as well as hippocampal region which suggests that andrographolide could be a novel pharmacological countermeasure for the treatment of neuroinflammation and neurological disorders related to memory impairment. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. Natural killer cells and their receptors in multiple sclerosis.

    Science.gov (United States)

    Kaur, Gurman; Trowsdale, John; Fugger, Lars

    2013-09-01

    The immune system has crucial roles in the pathogenesis of multiple sclerosis. While the adaptive immune cell subsets, T and B cells, have been the main focus of immunological research in multiple sclerosis, it is now important to realize that the innate immune system also has a key involvement in regulating autoimmune responses in the central nervous system. Natural killer cells are innate lymphocytes that play vital roles in a diverse range of infections. There is evidence that they influence a number of autoimmune conditions. Recent studies in multiple sclerosis and its murine model, experimental autoimmune encephalomyelitis, are starting to provide some understanding of the role of natural killer cells in regulating inflammation in the central nervous system. Natural killer cells express a diverse range of polymorphic cell surface receptors, which interact with polymorphic ligands; this interaction controls the function and the activation status of the natural killer cell. In this review, we discuss evidence for the role of natural killer cells in multiple sclerosis and experimental autoimmune encephalomyelitis. We consider how a change in the balance of signals received by the natural killer cell influences its involvement in the ensuing immune response, in relation to multiple sclerosis.

  17. Regulatory natural killer cell expression in atopic childhood asthma ...

    African Journals Online (AJOL)

    Introduction: Different subsets of natural killer (NK) cells were found to play a role in pathogenesis of allergy. We sought to investigate the expression of regulatory NK cells (CD56+CD16+CD158+) in atopic children with bronchial asthma in order to outline the value of these cells as biomarkers of disease severity and/or ...

  18. Depressed natural killer cell activity in acute myocardial infarction

    DEFF Research Database (Denmark)

    Klarlund, K; Pedersen, B K; Theander, T G

    1987-01-01

    Natural killer (NK) cell activity against K562 target cells was measured in patients within 24 h of acute myocardial infarction (AMI) and regularly thereafter for 6 weeks. NK cell activity was suppressed on days 1, 3, and 7 (P less than 0.01), day 14 (P less than 0.05) and at 6 weeks (P = 0.05) w...

  19. Psoralen with ultraviolet A-induced apoptosis of cutaneous lymphoma cell lines is augmented by type I interferons via the JAK1-STAT1 pathway

    DEFF Research Database (Denmark)

    Liszewski, Walter; Naym, David Gram; Biskup, Edyta

    2017-01-01

    to a homozygous nonsense mutation. RESULTS: PUVA caused G2/M cell cycle block and apoptosis of MyLa and HuT-78 accompanied by increase in the expression of the mitochondrial pro-apoptotic genes Bax, BAK, and PUMA and a downregulation in anti-apoptotic Bcl-2. p53 was induced and c-Myc was repressed by PUVA...

  20. Natural killer cells for immunotherapy – Advantages of cell lines over blood NK cells

    Directory of Open Access Journals (Sweden)

    Hans eKlingemann

    2016-03-01

    Full Text Available Natural killer cells are potent cytotoxic effector cells for cancer therapy and potentially for severe viral infections. However, there are technical challenges to obtain sufficient numbers of functionally active NK cells form a patient’s blood since they represent only 10% of the lymphocytes. Especially, cancer patients are known to have dysfunctional NK cells. The alternative is to obtain cells from a healthy donor, which requires depletion of the allogeneic T-cells. Establishing cell lines from donor blood NK cells have not been successful, in contrast to blood NK cells obtained from patients with a clonal NK cell lymphoma. Those cells can be expanded in culture in the presence of IL-2. However, except for the NK-92 cell line none of the other six known cell lines has consistent and reproducibly high anti-tumor cytotoxicity, nor can they be easily genetically manipulated to recognize specific tumor antigens or to augment monoclonal antibody activity through ADCC. NK-92 is also the only cell line product that has been widely given to patients with advanced cancer with demonstrated efficiency and minimal side effects.

  1. Identification of Natural Killer Cells by Immunoelectron Microscopy

    Science.gov (United States)

    Chaney; Rafferty; Warhol

    1996-10-01

    We employed immunoelectron microscopic techniques to localize natural killer cells (NK cells) in human lymph node and tonsil. These tissues were embedded in Lowicryl K4M. Thin sections were first reacted with anti-Leu-7 followed by anti-UCHL. Colloidal gold particles of different sizes were used as a label. NK cells were localized primarily in paracortical T-cell regions. The cells typed with these antisera include both large granular and agranular lymphocytes. No other cell types expressed the NK phenotype. These results illustrate the versatility of immunoelectron microscopy to solve problems beyond the resolution of the light microscope.

  2. Natural killer cell activity during premedication, anaesthesia and surgery

    DEFF Research Database (Denmark)

    Tønnesen, E; Mickley, H; Grunnet, N

    1983-01-01

    Natural killer (NK) cell activity of peripheral blood mononuclear cells was measured against K-562 target cells in a 51Cr release assay in eight patients undergoing total hip replacement surgery. Eight consecutive blood samples were taken from each patient. A significant increase of NK cell...... activity was observed after premedication with diazepam per os. The activity increased further during a combined anaesthesia (thiopentone + N2O + O2 + buprenorphene + pancuronium) and remained increased during surgery. Postoperatively, NK cell activity fell and remained depressed for a period of at least 5...... days. The findings of this study indicate that premedication, anaesthesia and surgery cause a rapid and transient increase in NK cell activity, followed by a decline in activity postoperatively. The transient increase in activity may be explained by mobilization of natural killer cells from extravasal...

  3. Natural Killer T Cells: An Ecological Evolutionary Developmental Biology Perspective

    Directory of Open Access Journals (Sweden)

    Amrendra Kumar

    2017-12-01

    Full Text Available Type I natural killer T (NKT cells are innate-like T lymphocytes that recognize glycolipid antigens presented by the MHC class I-like protein CD1d. Agonistic activation of NKT cells leads to rapid pro-inflammatory and immune modulatory cytokine and chemokine responses. This property of NKT cells, in conjunction with their interactions with antigen-presenting cells, controls downstream innate and adaptive immune responses against cancers and infectious diseases, as well as in several inflammatory disorders. NKT cell properties are acquired during development in the thymus and by interactions with the host microbial consortium in the gut, the nature of which can be influenced by NKT cells. This latter property, together with the role of the host microbiota in cancer therapy, necessitates a new perspective. Hence, this review provides an initial approach to understanding NKT cells from an ecological evolutionary developmental biology (eco-evo-devo perspective.

  4. Natural Killer T Cells: An Ecological Evolutionary Developmental Biology Perspective

    Science.gov (United States)

    Kumar, Amrendra; Suryadevara, Naveenchandra; Hill, Timothy M.; Bezbradica, Jelena S.; Van Kaer, Luc; Joyce, Sebastian

    2017-01-01

    Type I natural killer T (NKT) cells are innate-like T lymphocytes that recognize glycolipid antigens presented by the MHC class I-like protein CD1d. Agonistic activation of NKT cells leads to rapid pro-inflammatory and immune modulatory cytokine and chemokine responses. This property of NKT cells, in conjunction with their interactions with antigen-presenting cells, controls downstream innate and adaptive immune responses against cancers and infectious diseases, as well as in several inflammatory disorders. NKT cell properties are acquired during development in the thymus and by interactions with the host microbial consortium in the gut, the nature of which can be influenced by NKT cells. This latter property, together with the role of the host microbiota in cancer therapy, necessitates a new perspective. Hence, this review provides an initial approach to understanding NKT cells from an ecological evolutionary developmental biology (eco-evo-devo) perspective. PMID:29312339

  5. Biochemical events in naturally occurring forms of cell death.

    Science.gov (United States)

    Fesus, L

    1993-08-09

    Several molecular elements of programmed cell death and apoptosis have recently been revealed. The function of gene products which deliver the lethal 'hit' is still not known. Well-characterized and newly discovered cell surface structures (e.g. antigen receptors, FAS/APO-1), as well as transcriptional factors (steroid receptor, c-myc, P53, retinoblastoma protein and others), have been implicated in the initiation of the death pathway. Negative regulators of the process (ced-9 gene product in programmed death of cells in Caenorhabditis elegans and bcl-2 protein in apoptosis) have been described. Biochemical mechanisms responsible for the silent nature of natural deaths of cells include their rapid engulfment (mainly through integrin receptors), transglutaminase-catalyzed cross-linking of cellular proteins, and fragmentation of DNA. Several lines of evidence suggest that distinct molecular mechanisms may operate in various forms of natural cell death.

  6. Melatonin promotes Bax sequestration to mitochondria reducing cell susceptibility to apoptosis via the lipoxygenase metabolite 5-hydroxyeicosatetraenoic acid

    KAUST Repository

    Radogna, Flavia

    2015-03-01

    Extra-neurological functions of melatonin include control of the immune system and modulation of apoptosis. We previously showed that melatonin inhibits the intrinsic apoptotic pathway in leukocytes via stimulation of high affinity MT1/MT2 receptors, thereby promoting re-localization of the anti-apoptotic Bcl-2 protein to mitochondria. Here we show that Bcl-2 sequesters pro-apoptotic Bax into mitochondria in an inactive form after melatonin treatment, thus reducing cell propensity to apoptosis. Bax translocation and the anti-apoptotic effect of melatonin are strictly dependent on the presence of Bcl-2, and on the 5-lipoxygenase (5-LOX) metabolite 5-hydroxyeicosatetraenoic acid (5-HETE), which we have previously shown to be produced as a consequence of melatonin binding to its low affinity target calmodulin. Therefore, the anti-apoptotic effect of melatonin requires the simultaneous, independent interaction with high (MT1/MT2) and low (calmodulin) affinity targets, eliciting two independent signal transduction pathways converging into Bax sequestration and inactivation. MT1/MT2 vs. lipoxygenase pathways are activated by 10-9 vs. 10-5M melatonin, respectively; the anti-apoptotic effect of melatonin is achieved at 10-5M, but drops to 10-9M upon addition of exogenous 5-HETE, revealing that lipoxygenase activation is the rate-limiting pathway. Therefore, in areas of inflammation with increased 5-HETE levels, physiological nanomolar concentrations of melatonin may suffice to maintain leukocyte viability.

  7. Athymic nude rat. III natural cell mediated cytotoxicity.

    NARCIS (Netherlands)

    W.H. de Jong; P.A. Steerenberg; P.S. Ursem; A.D.M.E. Osterhaus (Albert); J.G. Vos (Joseph); E.J. Ruitenberg (Joost)

    1980-01-01

    textabstractHomozygous rnu/rnu and heterozygous +/rnu rats were investigated and compared with each other for the existence of natural cell-mediated cytotoxicity. Investigated were total, adherent, and nonadherent cell populations from spleen, peritoneal cavity, and mesenteric lymph node. The

  8. Role of phosphoproteins involved in chemoresistance of colorectal cancer stem cells and immuno phenotypic comparative analysis

    International Nuclear Information System (INIS)

    Stassi, G.; Canzonieri, V.

    2009-01-01

    Recent studies demonstrated that colon cancers contain a cellular subpopulation, with stem cell-like proprieties, able to initiate and sustain tumour growth. These cells, so-called Cancer Initiating Cells (CICs), express the transmembrane antigen CD133. CD133 positive cells show slow proliferation rate, high expression of ABC (ATP-binding cassette) transporters and anti-apoptotic factors making them resistant to conventional therapies

  9. Natural killer cells enhance the immune surveillance of cancer

    Directory of Open Access Journals (Sweden)

    Faisal Nouroz

    2016-04-01

    Full Text Available Immune system (IS is comprised of molecules, cells, tissues and organs involved in host defense mechanism from infectious agents or tumor cells. On crossing the cell barriers by these infectious agents, the defense mechanism is alerted by the immune system to respond against these invading microbes. Innate immune response (IIR and acquired immune response (AIR are working in parallel to control these invading microbes. IIR is composed of various types of phagocytes and lymphocytes, while AIR is comprised of T and B lymphocytes. All the cells of the immune system cooperatively work against infectious agents and cancerous cells but Natural killer (NK cells are playing an important role to respond to tumor by enhancing the expression of complementary domain (CD86 on dendritic cells (DCs and production of IL-12. NK cells demolished tumor through perforin and granzyme, which are important for immune surveillance and death of tumor cells induced by cytokines such as tumor necrosis factor (TNF, Fas ligand (CD178, interferon-γ (IFN-γ and IL-10. These cytokines have inhibited proliferation of tumor by inducing anti-angiogenic factors and maintaining cross talk with other immune cells. Natural products like transfer factor plus, immune modulator mix, ascorbic acid, Ganoderma lucidum, Agaricus blazei teas, nitrogenated soy extract, Andrographis paniculata and several phytochemicals enhanced the efficiency of NK cells in controlling cancers. Further studies will unravel the impact of NK cells in cancer control and how NK efficiency can be further enhanced.

  10. Signaling for synergistic activation of natural killer cells.

    Science.gov (United States)

    Kwon, Hyung-Joon; Kim, Hun Sik

    2012-12-01

    Natural killer (NK) cells play a pivotal role in early surveillance against virus infection and cellular transformation, and are also implicated in the control of inflammatory response through their effector functions of direct lysis of target cells and cytokine secretion. NK cell activation toward target cell is determined by the net balance of signals transmitted from diverse activating and inhibitory receptors. A distinct feature of NK cell activation is that stimulation of resting NK cells with single activating receptor on its own cannot mount natural cytotoxicity. Instead, specific pairs of co-activation receptors are required to unleash NK cell activation via synergy-dependent mechanism. Because each co-activation receptor uses distinct signaling modules, NK cell synergy relies on the integration of such disparate signals. This explains why the study of the mechanism underlying NK cell synergy is important and necessary. Recent studies revealed that NK cell synergy depends on the integration of complementary signals converged at a critical checkpoint element but not on simple amplification of the individual signaling to overcome intrinsic activation threshold. This review focuses on the signaling events during NK cells activation and recent advances in the study of NK cell synergy.

  11. Defective Natural Killer cell antiviral capacity in paediatric HBV infection

    DEFF Research Database (Denmark)

    Heiberg, Ida Louise; Laura J., Pallett; Winther, Thilde Nordmann

    2015-01-01

    Natural Killer (NK) cells exhibit dysregulated effector function in adult chronic HBV infection (CHB), which may contribute to virus persistence. The role of NK cells in children infected perinatally with HBV is less studied. Access to a unique cohort enabled the cross-sectional evaluation of NK...... cell frequency, phenotype and function in HBV-infected children relative to uninfected children. We observed a selective defect in NK cell IFN-γ production, with conserved cytolytic function, mirroring the functional dichotomy observed in adult infection. Reduced expression of NKp30 on NK cells...

  12. Glutamate-mediated protection of crayfish glial cells from PDT-induced apoptosis

    Science.gov (United States)

    Rudkovskii, M. V.; Romanenko, N. P.; Berezhnaya, E. V.; Kovaleva, V. D.; Uzdensky, A. B.

    2011-03-01

    Photodynamic treatment that causes intense oxidative stress and kills cells is currently used in neurooncology. However, along with tumor it damages surrounding healthy neurons and glial cells. In order to study the possible role of glutamate-related signaling pathways in photodynamic injury of neurons and glia, we investigated photodynamic effect of alumophthalocyanine Photosens on isolated crayfish stretch receptor that consists of a single neuron surrounded by glial cells. The laser diode (670 nm, 0.4 W/cm2) was used for dye photoexcitation. Application of glutamate increased photodynamically induced necrosis of neurons and glial cells but significantly decreased glial apoptosis. The natural neuroglial mediator N-acetylaspartylglutamate, which releases glutamate after cleavage in the extracellular space by glutamate carboxypeptidase II, also inhibited photoinduced apoptosis. Inhibition of glutamate carboxypeptidase II, oppositely, enhanced apoptosis of glial cells. These data confirm the anti-apoptotic activity of glutamate. Application of NMDA or inhibition of NMDA receptors by MK801 did not influence photodynamic death of neurons and glial cells that indicated nonparticipation of NMDA receptors in these processes. Inhibition of metabotropic glutamate receptors by AP-3 decreased PDT-induced apoptosis. One can suggest that crayfish neurons naturally secrete NAAG, which being cleaved by GCOP produces glutamate. Glutamate prevents photoinduced apoptosis of glial cells possibly through metabotropic but not ionotropic glutamate receptors.

  13. Natural Killer Cells as Helper Cells in Dendritic Cell Cancer Vaccines

    OpenAIRE

    Pampena, María Betina; Levy, Estrella Mariel

    2015-01-01

    Vaccine-based cancer immunotherapy has generated highly variable clinical results due to differing methods of vaccine preparation and variation in patient populations among other lesser factors. Moreover, these clinical responses do not necessarily correspond with the induction of tumor-specific cytotoxic lymphocytes. Here, we review the participation of natural killer (NK) cells as alternative immune components that could cooperate in successful vaccination treatment. NK cells have been desc...

  14. Natural and induced T regulatory cells in cancer

    Directory of Open Access Journals (Sweden)

    Dennis O Adeegbe

    2013-07-01

    Full Text Available CD4+Foxp3+ T regulatory (Treg cells control many facets of immune responses ranging from autoimmune diseases, to inflammatory conditions, and cancer in an attempt to maintain immune homeostasis. Natural Treg (nTreg cells develop in the thymus and constitute a critical arm of active mechanisms of peripheral tolerance particularly to self-antigens. A growing body of knowledge now supports the existence of induced Treg (iTreg cells which may derive from a population of conventional CD4+ T cells. The fork-head transcription factor (Foxp3 typically is expressed by natural CD4+ Treg cells, and thus serves as a marker to definitively identify these cells. On the contrary, there is less consensus on what constitutes iTreg cells as their precise definition has been somewhat elusive. This is in part due to their distinct phenotypes which are shaped by exposure to certain inflammatory or assault signals stemming from the underlying immune disorder. The policing activity of Treg cells tends to be uni-directional in several pathological conditions. On one end of the spectrum, Treg-cell suppressive activity is beneficial by curtailing T cell response against self-antigens and allergens thus preventing autoimmune diseases and allergies. On the other end however, their inhibitory roles in limiting immune response against pseudo-self antigens as in tumors often culminates into negative outcomes. In this review, we focus on this latter aspect of Treg-cell immunobiology by highlighting the involvement of nTreg cells in various animal models and human tumors. We further discuss iTreg cells, relationship with their natural counterpart, and potential co-operation between the two in modulating immune response against tumors. Lastly, we discuss studies focusing on these cells as targets for improving anti-tumor immunity.

  15. Present and future of allogeneic natural killer cell therapy

    Directory of Open Access Journals (Sweden)

    Okjae eLim

    2015-06-01

    Full Text Available Natural killer (NK cells are innate lymphocytes that are capable of eliminating tumor cells and are therefore used for cancer therapy. Although many early investigators used autologous NK cells, including lymphokine-activated killer cells, the clinical efficacies were not satisfactory. Meanwhile, human leukocyte antigen (HLA-haploidentical hematopoietic stem cell transplantation revealed the anti-tumor effect of allogeneic NK cells, and HLA-haploidentical, killer cell immunoglobulin-like receptor (KIR ligand-mismatched allogeneic NK cells are currently used for many protocols requiring NK cells. Moreover, allogeneic NK cells from non-HLA-related healthy donors have been recently used in cancer therapy. The use of allogeneic NK cells from non-HLA-related healthy donors allows the selection of donor NK cells with higher flexibility and to prepare expanded, cryopreserved NK cells for instant administration without delay for ex vivo expansion. In cancer therapy with allogeneic NK cells, optimal matching of donors and recipients is important to maximize the efficacy of the therapy. In this review, we summarize the present state of allogeneic NK cell therapy and its future directions.

  16. Stimulation of Natural Killer T Cells by Glycolipids

    Directory of Open Access Journals (Sweden)

    Brian L. Anderson

    2013-12-01

    Full Text Available Natural killer T (NKT cells are a subset of T cells that recognize glycolipid antigens presented by the CD1d protein. The initial discovery of immunostimulatory glycolipids from a marine sponge and the T cells that respond to the compounds has led to extensive research by chemists and immunologists to understand how glycolipids are recognized, possible responses by NKT cells, and the structural features of glycolipids necessary for stimulatory activity. The presence of this cell type in humans and most mammals suggests that it plays critical roles in antigen recognition and the interface between innate and adaptive immunity. Both endogenous and exogenous natural antigens for NKT cells have been identified, and it is likely that glycolipid antigens remain to be discovered. Multiple series of structurally varied glycolipids have been synthesized and tested for stimulatory activity. The structural features of glycolipids necessary for NKT cell stimulation are moderately well understood, and designed compounds have proven to be much more potent antigens than their natural counterparts. Nevertheless, control over NKT cell responses by designed glycolipids has not been optimized, and further research will be required to fully reveal the therapeutic potential of this cell type.

  17. Chloride intracellular channel 1 identified using proteomic analysis plays an important role in the radiosensitivity of HEp-2 cells via reactive oxygen species production.

    Science.gov (United States)

    Kim, Jae-Sung; Chang, Jong Wook; Yun, Hong Shik; Yang, Kyung Mi; Hong, Eun-Hee; Kim, Dong Hyun; Um, Hong-Duck; Lee, Kee-Ho; Lee, Su-Jae; Hwang, Sang-Gu

    2010-07-01

    The nature of the molecules underlying the radioresistance phenotype of laryngeal cancer cells remains to be established. We initially generated radioresistant laryngeal cancer cell lines from human HEp-2 cells with fractionated radiation. These RR-HEp-2 cells and isolated clones displayed more radioresistant and anti-apoptotic phenotypes than parental HEp-2 cells after radiation. Characteristics of RR-Hep-2 cell lines were confirmed by upregulation of radioresistance-related genes, such as epidermal growth factor receptor, Hsp90, and Bcl-xl. Subsequently, we examined proteome changes between HEp-2 and RR-HEp-2 cells and identified 16 proteins showing significantly altered expression levels. Interestingly, protein expression of chloride intracellular channel 1 (CLIC1) was markedly suppressed in RR-HEp-2 cells, compared with non-irradiated control cells. Suppression of CLIC1 with an indanyloxyacetic acid-94 or small interfering RNA led to radioresistance in HEp-2 cells by suppressing the radiation-induced cellular ROS level. However, ectopic overexpression of CLIC1 induced radiosensitivity in RR-HEp-2 cells via induction of ROS level after radiation, suggesting that the protein acts as a positive regulator of ROS production. Our results collectively indicate that suppression of CLIC1 contributes to acquisition of the radioresistance phenotype of laryngeal cancer cells via inhibition of ROS production, implying that this protein is an important candidate molecule for radiotherapy in radioresistant laryngeal cancer cells.

  18. Advantages and Applications of CAR-Expressing Natural Killer Cells

    Directory of Open Access Journals (Sweden)

    Wolfgang eGlienke

    2015-02-01

    Full Text Available In contrast to donor T cells, natural killer (NK cells are known to mediate anti-cancer effects without the risk of inducing graft-versus-host disease (GvHD. In order to improve cytotoxicity against resistant cancer cells, auspicious efforts have been made with chimeric antigen receptor (CAR expressing T- and NK cells. These CAR-modified cells express antigen receptors against tumor-associated surface antigens, thus redirecting the effector cells and enhancing tumor-specific immunosurveillance. However, many cancer antigens are also expressed on healthy tissues, potentially leading to off tumor/ on target toxicity by CAR-engineered cells. In order to control such potentially severe side effects, the insertion of suicide genes into CAR-modified effectors can provide a means for efficient depletion of these cells. While CAR-expressing T cells have entered successfully clinical trials, experience with CAR-engineered NK cells is mainly restricted to pre-clinical investigations and predominantly to NK cell lines. In this review we summarize the data on CAR expressing NK cells focusing on the possible advantage using these short-lived effector cells and discuss the necessity of suicide switches. Furthermore, we address the compliance of such modified NK cells with regulatory requirements as a new field in cellular immunotherapy.

  19. Induction of ROS Overload by Alantolactone Prompts Oxidative DNA Damage and Apoptosis in Colorectal Cancer Cells

    Directory of Open Access Journals (Sweden)

    Yushuang Ding

    2016-04-01

    Full Text Available Cancer cells typically display higher than normal levels of reactive oxygen species (ROS, which may promote cancer development and progression but may also render the cancer cells more vulnerable to further ROS insult. Indeed, many of the current anticancer therapeutics kill cancer cells via induction of oxidative stress, though they target both cancer and normal cells. Recently, alantolactone (ATL, a natural sesquiterpene lactone, has been shown to induce apoptosis by increasing ROS levels specifically in cancer cells; however, the molecular mechanisms linking ROS overproduction to apoptosis remain unclear. Here we show that the ATL-induced ROS overload in human SW480 and SW1116 colorectal cancer cells was followed by a prominent accumulation of cellular oxidized guanine (8-oxoG and immediate increase in the number of DNA strand breaks, indicating that increased ROS resulted in extensive oxidative DNA damage. Consequently, the G1/S-CDK suppresser CDKN1B (p21 and pro-apoptotic proteins Bax and activated caspase-3 were upregulated, while anti-apoptotic Bcl-2 was downregulated, which were followed by cell cycle arrest at G1 and marked apoptosis in ATL-treated cancer but not non-cancer cells. These results suggest that the ATL-induced ROS overload triggers cell death through induction of massive oxidative DNA damage and subsequent activation of the intrinsic apoptosis pathway.

  20. Natural Killer cells as helper cells in Dendritic cell cancer vaccines

    Directory of Open Access Journals (Sweden)

    María Betina Pampena

    2015-01-01

    Full Text Available Vaccine-based cancer immunotherapy has generated highly variable clinical results due to differing methods of vaccine preparation and variation in patient populations, among other lesser factors. Moreover, these clinical responses do not necessarily correspond with the induction of tumor-specific cytotoxic lymphocytes. Here we review the participation of natural killer (NK cells as alternative immune components that could cooperate in successful vaccination treatment. NK cells have been described as helper cells in dendritic cell-based cancer vaccines, but the role in other kinds of vaccination strategies (whole cells, peptide or DNA- based vaccines is poorly understood. In this article we address the following issues regarding the role of NK cells in cancer vaccines: NK cell anti-tumor action sites, and the loci of NK cell interaction with other immune cells; descriptions of new data on the memory characteristics of NK cells described in infectious diseases; and finally phenotypical and functional changes after vaccination measured by immunomonitoring in preclinical and clinical settings.

  1. Natural killer T (NKT) cells in autoimmune hepatitis.

    Science.gov (United States)

    Mattner, Jochen

    2013-12-01

    Natural killer T (NKT) cells represent an innate-like lymphocyte population endowed with unique antigen recognition and tissue distribution features. Their abundance in the microvascular compartments of the liver allows NKT cells to immediately respond to lipid antigens and soluble factors circulating through the portal vein system by releasing tremendous amounts of different cytokines and chemokines. Subsequently, dependent on the nature of the lipid antigen encountered as well as the accessory signal(s) provided, NKT cells not only contribute to the maintenance of immune tolerance, but also direct adverse immune reactions locally and systemically. Focusing on their potent immunomodulatory features and their interactions with various innate and adaptive immune cells, the role of NKT cells in perpetuating the loss of liver-specific immune tolerance will be discussed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. Human CD1d-Restricted Natural Killer T (NKT) Cell Cytotoxicity Against Myeloid Cells

    National Research Council Canada - National Science Library

    Chen, Xiuxu; Gumperz, Jenny E

    2006-01-01

    CD1d-restricted natural killer T cells (NKT cells) are a unique subpopulation of T lymphocytes that have been shown to be able to promote potent anti-tumor responses in a number of different murine (mouse...

  3. Natural Killer Cells in the Orchestration of Chronic Inflammatory Diseases

    Directory of Open Access Journals (Sweden)

    Luca Parisi

    2017-01-01

    Full Text Available Inflammation, altered immune cell phenotype, and functions are key features shared by diverse chronic diseases, including cardiovascular, neurodegenerative diseases, diabetes, metabolic syndrome, and cancer. Natural killer cells are innate lymphoid cells primarily involved in the immune system response to non-self-components but their plasticity is largely influenced by the pathological microenvironment. Altered NK phenotype and function have been reported in several pathological conditions, basically related to impaired or enhanced toxicity. Here we reviewed and discussed the role of NKs in selected, different, and “distant” chronic diseases, cancer, diabetes, periodontitis, and atherosclerosis, placing NK cells as crucial orchestrator of these pathologic conditions.

  4. Uterine natural killer cells during pregnancy in rodents.

    Science.gov (United States)

    Head, J R

    Large mononuclear cells with abundant prominent granules were described decades ago by morphologists studying implantation sites in pregnant rodents. These striking cells accumulated by midgestation in large numbers in a structure unique to rodent pregnancy that develops in the mesometrial region of the uterine musculature and was given the unfortunate name of metrial gland. Thus, the cells were originally termed granulated metrial gland (GMG) cells. Evidence provided over the last few years, especially in situ phenotyping and studies in mutant and transgenic mice, has reliably identified these cells as members of the natural killer (NK) cell lineage, and they are referred to here as granulated uterine NK (uNK) cells. Much of the evidence is reviewed here, along with a description of the spatial and temporal aspects of the differentiation of these cells. Especially highlighted are their life history and their likely importance early in pregnancy before development of the metrial gland proper. Their relation to other NK cell populations, especially activated cells, as well as their possible functions during pregnancy, are discussed. Because these cells develop in the unique microenvironment of the pregnant uterus and appear to differentiate along a specific pathway, hypotheses are proposed regarding the regulation of granulated uNK cell differentiation in this site.

  5. Immunotherapeutic strategies targeting Natural killer T cell responses in cancer

    Science.gov (United States)

    Shissler, Susannah C.; Bollino, Dominique R.; Tiper, Irina V.; Bates, Joshua; Derakhshandeh, Roshanak; Webb, Tonya J.

    2017-01-01

    Natural killer T (NKT) cells are a unique subset of lymphocytes that bridge the innate and adaptive immune system. NKT cells possess a classic αβ T-cell receptor (TCR) that is able to recognize self and foreign glycolipid antigens presented by the nonclassical class I major histocompatibility complex (MHC) molecule, CD1d. Type I NKT cells (referred to as invariant NKT cells) express a semi-invariant Vα14Jα18 TCR in mice and Vα24Jα18 TCR in humans. Type II NKT cells are CD1d-restricted T cells that express a more diverse set of TCR α chains. The two types of NKT cells often exert opposing effects especially in tumor immunity, where Type II cells generally suppress tumor immunity while Type I NKT cells can enhance antitumor immune responses. In this review, we focus on the role of NKT cells in cancer. We discuss their effector and suppressive functions, as well as describe preclinical and clinical studies utilizing therapeutic strategies focused on harnessing their potent anti-tumor effector functions, and conclude with a discussion on potential next steps for the utilization of NKT cell targeted therapies for the treatment of cancer. PMID:27393665

  6. Biophotovoltaics: Natural pigments in dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Hug, Hubert; Bader, Michael; Mair, Peter; Glatzel, Thilo

    2014-01-01

    Highlights: • Natural pigments are photosensitizers in dye-sensitized solar cells (DSSCs). • Efficiency is still lower compared to synthetic pigments. • The use of natural pigments such as carotenoids and polyphenols is cheap. • General advantages of DSSCs are flexibility, color and transparency. • Usage under diffuse light and therefore, indoor applications are possible. - Abstract: Dye-sensitized solar cells (DSSCs) which are also called Graetzel cells are a novel type of solar cells. Their advantages are mainly low cost production, low energy payback time, flexibility, performance also at diffuse light and multicolor options. DSSCs become more and more interesting since a huge variety of dyes including also natural dyes can be used as light harvesting elements which provide the charge carriers. A wide band gap semiconductor like TiO 2 is used for charge separation and transport. Such a DSSC contains similarities to the photosynthetic apparatus. Therefore, we summarize current available knowledge on natural dyes that have been used in DSSCs which should provide reasonable light harvesting efficiency, sustainability, low cost and easy waste management. Promising natural compounds are carotenoids, polyphenols and chlorophylls

  7. Natural Killer Dendritic Cells Enhance Immune Responses Elicited by α-Galactosylceramide-Stimulated Natural Killer T Cells

    Directory of Open Access Journals (Sweden)

    Sung Won Lee

    2013-01-01

    Full Text Available 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.

  8. Activation of Natural Killer cells during microbial infections

    Directory of Open Access Journals (Sweden)

    Amir eHorowitz

    2012-01-01

    Full Text Available Natural killer (NK cells are large granular lymphocytes that express a diverse array of germline encoded inhibitory and activating receptors for MHC Class I and Class I-like molecules, classical co-stimulatory ligands and cytokines. The ability of NK cells to be very rapidly activated by inflammatory cytokines, to secrete effector cytokines and to kill infected or stressed host cells, suggests that they may be among the very early responders during infection. Recent studies have also identified a small number of pathogen-derived ligands that can bind to NK cell surface receptors and directly induce their activation. Here we review recent studies that have begun to elucidate the various pathways by which viral, bacterial and parasite pathogens activate NK cells. We also consider two emerging themes of NK cell-pathogen interactions, namely their contribution to adaptive immune responses and their potential to take on regulatory and immunomodulatory functions.

  9. Activation mechanisms of natural killer cells during influenza virus infection.

    Directory of Open Access Journals (Sweden)

    Ilwoong Hwang

    Full Text Available During early viral infection, activation of natural killer (NK cells elicits the effector functions of target cell lysis and cytokine production. However, the cellular and molecular mechanisms leading to NK cell activation during viral infections are incompletely understood. In this study, using a model of acute viral infection, we investigated the mechanisms controlling cytotoxic activity and cytokine production in response to influenza (flu virus. Analysis of cytokine receptor deficient mice demonstrated that type I interferons (IFNs, but not IL-12 or IL-18, were critical for the NK cell expression of both IFN-γ and granzyme B in response to flu infection. Further, adoptive transfer experiments revealed that NK cell activation was mediated by type I IFNs acting directly on NK cells. Analysis of signal transduction molecules showed that during flu infection, STAT1 activation in NK cells was completely dependent on direct type I IFN signaling, whereas STAT4 activation was only partially dependent. In addition, granzyme B induction in NK cells was mediated by signaling primarily through STAT1, but not STAT4, while IFN-γ production was mediated by signaling through STAT4, but not STAT1. Therefore, our findings demonstrate the importance of direct action of type I IFNs on NK cells to mount effective NK cell responses in the context of flu infection and delineate NK cell signaling pathways responsible for controlling cytotoxic activity and cytokine production.

  10. Natural killer cell distribution and trafficking in human tissues

    Directory of Open Access Journals (Sweden)

    Guido eFerlazzo

    2012-11-01

    Full Text Available Few data are available regarding the recirculation of natural killer (NK cells among human organs. Earlier studies have been often impaired by the use of markers then proved to be either not sufficiently specific for NK cells (e.g. CD57, CD56 or expressed only by subsets of NK cells (e.g. CD16. At the present, available data confirmed that human NK cells populate blood, lymphoid organs, lung, liver, uterus (during pregnancy and gut. Several studies showed that NK cell homing appears to be subset-specific, as secondary lymphoid organs and probably several solid tissues are preferentially inhabited by CD56brightCD16neg/dull non-cytotoxic NK cells. Similar studies performed in the mouse model showed that lymph node and bone marrow are preferentially populated by CD11bdull NK cells while blood, spleen and lung by CD27dull NK cells. Therefore, an important topic to be addressed in the human system is the contribution of factors that regulate NK cell tissue homing and egress, such as chemotactic receptors or homeostatic mechanisms. Here, we review the current knowledge on NK cell distribution in peripheral tissues and, based on recent acquisitions, we propose our view regarding the recirculation of NK cells in the human body.

  11. Characterization of circulating natural killer cells in neotropical primates.

    Directory of Open Access Journals (Sweden)

    Angela Carville

    Full Text Available Despite extensive use of nonhuman primates as models for infectious diseases and reproductive biology, imprecise phenotypic and functional definitions exist for natural killer (NK cells. This deficit is particularly significant in the burgeoning use of small, less expensive New World primate species. Using polychromatic flow cytometry, we identified peripheral blood NK cells as CD3-negative and expressing a cluster of cell surface molecules characteristic of NK cells (i.e., NKG2A, NKp46, NKp30 in three New World primate species - common marmosets, cotton-top tamarins, and squirrel monkeys. We then assessed subset distribution using the classical NK markers, CD56 and CD16. In all species, similar to Old World primates, only a minor subset of NK cells was CD56+, and the dominant subset was CD56-CD16+. Interestingly, CD56+ NK cells were primarily cytokine-secreting cells, whereas CD56-CD16+ NK cells expressed significantly greater levels of intracellular perforin, suggesting these cells might have greater potential for cytotoxicity. New World primate species, like Old World primates, also had a minor CD56-CD16- NK cell subset that has no obvious counterpart in humans. Herein we present phenotypic profiles of New World primate NK cell subpopulations that are generally analogous to those found in humans. This conservation among species should support the further use of these species for biomedical research.

  12. Immune evasion of natural killer cells by viruses.

    Science.gov (United States)

    Jonjić, Stipan; Babić, Marina; Polić, Bojan; Krmpotić, Astrid

    2008-02-01

    Natural killer (NK) cells are important in the host resistance to viral infections. They are among the first cells to sense the release of proinflammatory cytokines, as well as the downregulation of surface MHC class I molecules and molecules induced by viral invasion of cells. Various viral functions have evolved to counter NK cell responses illustrating the evolutionary struggles between viruses and NK cells. Ligands for NK cell receptors are primary targets for viral immunoevasion. In order to counteract NK cell activation via the 'missing self'-axis, viruses encode proteins which serve as ligands for inhibitory NK cell receptors. Viruses also downmodulate the ligands for the activating NK cell receptors and encode soluble ligands which block these receptors. In addition to viral immunoregulatory proteins, regulatory RNAs can also inhibit the expression of ligands for NK cell receptors. Improving our understanding of viral regulation of NK cell function could be essential for designing more efficient measures in the prophylaxis and treatment of virus-induced pathology.

  13. The effects of IL-17 upon human natural killer cells.

    Science.gov (United States)

    Al Omar, Suliman; Flanagan, Brian F; Almehmadi, Mazen; Christmas, Stephen E

    2013-04-01

    These experiments were designed to investigate the effects of IL-17 upon the phenotype and function of human Natural Killer (NK) cells. Peripheral blood mononuclear cells from healthy subjects were cultured in the presence or absence of different combinations of IL-17s and changes in relative numbers and cell surface phenotype of NK cells and CD56+CD3+ cells measured by flow cytometry. Real time PCR was used to measure changes in expression of the cytotoxicity-related genes perforin A and granzymes A and B and IL-17 receptors. A chromium release assay was used to measure cytotoxic function against K562 tumour cells. IL-17D, IL-17A, IL-17F or the combination of both of the latter had little effect upon NK cell surface expression of Killer Immunoglobulin-like Receptors, although IL-17A modestly increased NK cell numbers. Slight but not significant increases in expression of perforin and granzymes were induced by IL-17A and/or IL-17F. Both IL-17A and D significantly increased cytotoxic function of NK cells at some E:T ratios. Similarly, numbers of NK cells induced to express CD107a after interaction with K562 cells were increased, but not significantly, by all combinations of IL-17s tested. IL-17RC was not found at the NK cell surface but was expressed at the message level and the protein detected intracellularly. NK cells are known to produce IL-17 but here we report that there is little response to this cytokine although some isoforms may moderately enhance cytotoxic function. There may therefore be some enhancement of NK cell function resulting from Th17 cell activation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Natural killer T cells in adipose tissue prevent insulin resistance

    NARCIS (Netherlands)

    Schipper, H.S.; Rakhshandehroo, M.; Graaf, van de S.F.J.; Venken, K.; Koppen, A.; Stienstra, R.; Prop, S.; Meerding, J.; Hamers, N.; Besra, G.S.; Boon, den L.; Nieuwenhuis, E.E.S.; Elewaut, D.; Prakken, B.; Kersten, A.H.; Boes, M.; Kalkhoven, E.

    2012-01-01

    Lipid overload and adipocyte dysfunction are key to the development of insulin resistance and can be induced by a high-fat diet. CD1d-restricted invariant natural killer T (iNKT) cells have been proposed as mediators between lipid overload and insulin resistance, but recent studies found decreased

  15. Processing of natural temporal stimuli by macaque retinal ganglion cells

    NARCIS (Netherlands)

    Hateren, J.H. van; Rüttiger, L.; Lee, B.B.

    2002-01-01

    This study quantifies the performance of primate retinal ganglion cells in response to natural stimuli. Stimuli were confined to the temporal and chromatic domains and were derived from two contrasting environments, one typically northern European and the other a flower show. The performance of the

  16. Electrochemical cell studies on fluorinated natural graphite in ...

    Indian Academy of Sciences (India)

    Administrator

    Keywords. Lithium battery; low temperature; fluoroester additive; organic electrolyte; natural graphite. 1. Introduction. In recent years, the application of the carboneous materials are widely dispersed in all form of the energy storage devices such as lithium battery, fuel cell and capacitor applications due to their safety,.

  17. Antitumor Responses of Invariant Natural Killer T Cells

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    Jennie B. Altman

    2015-01-01

    Full Text Available Natural killer T (NKT cells are innate-like lymphocytes that were first described in the late 1980s. Since their initial description, numerous studies have collectively shed light on their development and effector function. These studies have highlighted the unique requirements for the activation of these lymphocytes and the functional responses that distinguish these cells from other effector lymphocyte populations such as conventional T cells and NK cells. This body of literature suggests that NKT cells play diverse nonredundant roles in a number of disease processes, including the initiation and propagation of airway hyperreactivity, protection against a variety of pathogens, development of autoimmunity, and mediation of allograft responses. In this review, however, we focus on the role of a specific lineage of NKT cells in antitumor immunity. Specifically, we describe the development of invariant NKT (iNKT cells and the factors that are critical for their acquisition of effector function. Next, we delineate the mechanisms by which iNKT cells influence and modulate the activity of other immune cells to directly or indirectly affect tumor growth. Finally, we review the successes and failures of clinical trials employing iNKT cell-based immunotherapies and explore the future prospects for the use of such strategies.

  18. Human natural killer cell development in secondary lymphoid tissues

    Science.gov (United States)

    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

  19. In vitro Natural Killer cell immunotherapy for medulloblastoma

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    Lucia eFernandez

    2013-04-01

    Full Text Available How the immune system attacks medulloblastoma (MB tumours effectively is unclear, although natural killer (NK cells play an important role in immune defence against tumour cells. Interactions between receptors on NK cells and ligands expressed by tumour cells are critical for tumour control by immunotherapy. In this study, we analysed tumour samples from 54 MB patients for expression of major histocompatibility complex class I-related chains A (MICA and UL16 binding protein (ULPB-2, which are ligands for the NK group 2 member D activatory receptor (NKG2D. The percentage of MICA and ULBP-2 positive cells was higher than 25% in 68% and 6% of MB patients, respectively. A moderate-high intensity of MICA cytoplasmic staining was observed in 46% MB patients and weak ULBP-2 staining was observed in 8% MB patients. No correlation between MICA/ULBP-2 expression and patient outcome was found. We observed that HTB-186, a medulloblastoma cell line, was moderately resistant to NK cell cytotoxicity in vitro. Blocking MICA/ULBP-2 on HTB-186, and NKG2D receptor on NK cells increased resistance to NK cell lysis in vitro. However, HLA class I blocking on HTB-186 and overnight incubation with IL-15 stimulated NK cells efficiently to kill tumour cells in vitro. We conclude that although NKG2D/MICA-ULBP-2 interactions have a role in NK cell cytotoxicity against MB, high expression of HLA class I can protect MB from NK cell cytotoxicity. Even so, our in vitro data indicate that if NK cells are appropriately stimulated, they may have the potential to target MB in vivo.

  20. Cell Therapy in Cardiovascular Disease

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    Hoda Madani

    2014-05-01

    Full Text Available   Recently, cell therapy has sparked a revolution in ischemic heart disease that will in the future help clinicians to cure patients. Earlier investigations in animal models and clinical trials have suggested that positive paracrine effects such as neoangiogenesis and anti-apoptotic can improve myocardial function. In this regard the Royan cell therapy center designed a few trials in collaboration with multi hospitals such as Baqiyatallah, Shahid Lavasani, Tehran Heart Center, Shahid rajaee, Masih daneshvari, Imam Reza, Razavi and Sasan from 2006. Their results were interesting. However, cardiac stem cell therapy still faces great challenges in optimizing the treatment of patients. Keyword: Cardiovascular disease, Cell therapy.  

  1. Leukemia-associated gene MLAA-34 reduces arsenic trioxide-induced apoptosis in HeLa cells via activation of the Wnt/β-catenin signaling pathway.

    Science.gov (United States)

    Zhang, Pengyu; Zhao, Xuan; Zhang, Wenjuan; He, Aili; Lei, Bo; Zhang, Wanggang; Chen, Yinxia

    2017-01-01

    Our laboratory previously used the SEREX method in U937 cells and identified a novel leukemia-associated gene MLAA-34, a novel splice variant of CAB39L associated with acute monocytic leukemia, that exhibited anti-apoptotic activities in U937 cells. Whether MLAA-34 has an anti-apoptotic role in other tumor cells has not yet been reported. We explored whether MLAA-34 exhibited anti-apoptotic effects in HeLa cervical cancer cells and the possible mechanism of action. We generated a HeLa cell line stably expressing MLAA-34 and found that MLAA-34 overexpression had no effect on the growth, apoptosis and cell cycle of HeLa cells. However, upon treatment with arsenic trioxide (ATO) to induce apoptosis, the cell viability and colony formation ability of ATO-treated MLAA-34 stable HeLa cells were significantly higher than that of ATO-treated controls, and the apoptosis rate and proportion of G2/M cells also decreased. We found that ATO treatment of HeLa cells resulted in significant decreases in the expression of β-catenin mRNA and protein and the downstream target factors c-Myc, cyclin B1, and cyclin D1 in the Wnt signaling pathway. Notably, ATO-treated MLAA-34 stable HeLa cells showed a significant reduction in the ATO-mediated downregulation of these factors. In addition, MLAA-34 overexpression significantly increased the expression of nuclear β-catenin protein in ATO-treated cells compared with HeLa cells treated only with ATO. Thus, here we have found that the Wnt/β-catenin signaling pathway is involved in ATO-induced apoptosis in HeLa cells. MLAA-34 reduces ATO-induced apoptosis and G2/M arrest, and the anti-apoptotic effect may be achieved by activating the Wnt/β-catenin signaling pathway in HeLa cells.

  2. Human Herpesviridae Methods of Natural Killer Cell Evasion

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    Carl I. Odom

    2012-01-01

    Full Text Available Human herpesviruses cause diseases of considerable morbidity and mortality, ranging from encephalitis to hematologic malignancies. As evidence emerges about the role of innate immunity and natural killer (NK cells in the control of herpesvirus infection, evidence of viral methods of innate immune evasion grows as well. These methods include interference with the ligands on infected cell surfaces that bind NK cell activating or inhibitory receptors. This paper summarizes the most extensively studied NK cell receptor/ligand pairs and then describes the methods of NK cell evasion used by all eight herpesviruses through these receptors and ligands. Although great strides have been made in elucidating their mechanisms, there is still a disparity between viruses in the amount of knowledge regarding innate immune evasion. Further research of herpesvirus innate immune evasion can provide insight for circumventing viral mechanisms in future therapies.

  3. Human herpesviridae methods of natural killer cell evasion.

    Science.gov (United States)

    Odom, Carl I; Gaston, David C; Markert, James M; Cassady, Kevin A

    2012-01-01

    Human herpesviruses cause diseases of considerable morbidity and mortality, ranging from encephalitis to hematologic malignancies. As evidence emerges about the role of innate immunity and natural killer (NK) cells in the control of herpesvirus infection, evidence of viral methods of innate immune evasion grows as well. These methods include interference with the ligands on infected cell surfaces that bind NK cell activating or inhibitory receptors. This paper summarizes the most extensively studied NK cell receptor/ligand pairs and then describes the methods of NK cell evasion used by all eight herpesviruses through these receptors and ligands. Although great strides have been made in elucidating their mechanisms, there is still a disparity between viruses in the amount of knowledge regarding innate immune evasion. Further research of herpesvirus innate immune evasion can provide insight for circumventing viral mechanisms in future therapies.

  4. 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

    Directory of Open Access Journals (Sweden)

    Milan Fiala

    2015-02-01

    Full Text Available 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.

  5. Natural Killer Cells in Viral HepatitisSummary

    Directory of Open Access Journals (Sweden)

    Barbara Rehermann

    2015-11-01

    Full Text Available Natural killer (NK cells are traditionally regarded as first-line effectors of the innate immune response, but they also have a distinct role in chronic infection. Here, we review the role of NK cells against hepatitis C virus (HCV and hepatitis B virus (HBV, two agents that cause acute and chronic hepatitis in humans. Interest in NK cells was initially sparked by genetic studies that demonstrated an association between NK cell–related genes and the outcome of HCV infection. Viral hepatitis also provides a model to study the NK cell response to both endogenous and exogenous type I interferon (IFN. Levels of IFN-stimulated genes increase in both acute and chronic HCV infection and pegylated IFNα has been the mainstay of HCV and HBV treatment for decades. In chronic viral hepatitis, NK cells display decreased production of antiviral cytokines. This phenotype is found in both HCV and HBV infection but is induced by different mechanisms. Potent antivirals now provide the opportunity to study the reversibility of the suppressed cytokine production of NK cells in comparison with the antigen-induced defect in IFNγ and tumor necrosis factor-α production of virus-specific T cells. This has implications for immune reconstitution in other conditions of chronic inflammation and immune exhaustion, such as human immunodeficiency virus infection and cancer. Keywords: HBV, HCV, Infection, Interferon, T Cell

  6. Inhibition of Oncogenic Transcription Factor REL by the Natural Product Derivative Calafianin Monomer 101 Induces Proliferation Arrest and Apoptosis in Human B-Lymphoma Cell Lines

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    Alan T. Yeo

    2015-04-01

    Full Text Available Increased activity of transcription factor NF-κB has been implicated in many B-cell lymphomas. We investigated effects of synthetic compound calafianin monomer (CM101 on biochemical and biological properties of NF-κB. In human 293 cells, CM101 selectively inhibited DNA binding by overexpressed NF-κB subunits REL (human c-Rel and p65 as compared to NF-κB p50, and inhibition of REL and p65 DNA binding by CM101 required a conserved cysteine residue. CM101 also inhibited DNA binding by REL in human B-lymphoma cell lines, and the sensitivity of several B-lymphoma cell lines to CM101-induced proliferation arrest and apoptosis correlated with levels of cellular and nuclear REL. CM101 treatment induced both phosphorylation and decreased expression of anti-apoptotic protein Bcl-XL, a REL target gene product, in sensitive B-lymphoma cell lines. Ectopic expression of Bcl-XL protected SUDHL-2 B-lymphoma cells against CM101-induced apoptosis, and overexpression of a transforming mutant of REL decreased the sensitivity of BJAB B-lymphoma cells to CM101-induced apoptosis. Lipopolysaccharide-induced activation of NF-κB signaling upstream components occurred in RAW264.7 macrophages at CM101 concentrations that blocked NF-κB DNA binding. Direct inhibitors of REL may be useful for treating B-cell lymphomas in which REL is active, and may inhibit B-lymphoma cell growth at doses that do not affect some immune-related responses in normal cells.

  7. Tissue detection of natural killer cells in colorectal adenocarcinoma

    Directory of Open Access Journals (Sweden)

    Patsouris Efstratios S

    2004-09-01

    Full Text Available Abstract Background Natural killer (NK cells represent a first line of defence against a developing cancer; however, their exact role in colorectal cancer remains undetermined. The aim of the present study was to evaluate the expression of CD16 and CD57 [immunohistochemical markers of natural NK cells] in colorectal adenocarcinoma. Methods Presence of NK cells was investigated in 82 colorectal adenocarcinomas. Immunohistochemical analysis was performed, using 2 monoclonal antibodies (anti-Fc Gamma Receptor II, CD16 and an equivalent to Leu-7, specific for CD-57. The number of immunopositive cells (% was evaluated by image analysis. The cases were characterized according to: patient gender and age, tumor location, size, grade, bowel wall invasion, lymph node metastases and Dukes' stage. Results NK cells were detected in 79/82 cases at the primary tumor site, 27/33 metastatic lymph nodes and 3/4 hepatic metastases; they were detected in levels similar to those reported in the literature, but their presence was not correlated to the clinical or pathological characteristics of the series, except for a negative association with the patients' age (p = 0.031. Conclusions Our data do not support an association of NK cell tissue presence with clinical or pathological variables of colorectal adenocarcinoma, except for a negative association with the patients' age; this might possibly be attributed to decreased adhesion molecule expression in older ages.

  8. Natural Escherichia coli strains undergo cell-to-cell plasmid transformation.

    Science.gov (United States)

    Matsumoto, Akiko; Sekoguchi, Ayuka; Imai, Junko; Kondo, Kumiko; Shibata, Yuka; Maeda, Sumio

    2016-12-02

    Horizontal gene transfer is a strong tool that allows bacteria to adapt to various environments. Although three conventional mechanisms of horizontal gene transfer (transformation, transduction, and conjugation) are well known, new variations of these mechanisms have also been observed. We recently reported that DNase-sensitive cell-to-cell transfer of nonconjugative plasmids occurs between laboratory strains of Escherichia coli in co-culture. We termed this phenomenon "cell-to-cell transformation." In this report, we found that several combinations of Escherichia coli collection of reference (ECOR) strains, which were co-cultured in liquid media, resulted in DNase-sensitive cell-to-cell transfer of antibiotic resistance genes. Plasmid isolation of these new transformants demonstrated cell-to-cell plasmid transfer between the ECOR strains. Natural transformation experiments, using a combination of purified plasmid DNA and the same ECOR strains, revealed that cell-to-cell transformation occurs much more frequently than natural transformation under the same culture conditions. Thus, cell-to-cell transformation is both unique and effective. In conclusion, this study is the first to demonstrate cell-to-cell plasmid transformation in natural E. coli strains. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Natural Compounds from Saffron and Bear Bile Prevent Vision Loss and Retinal Degeneration.

    Science.gov (United States)

    Fernández-Sánchez, Laura; Lax, Pedro; Noailles, Agustina; Angulo, Antonia; Maneu, Victoria; Cuenca, Nicolás

    2015-07-31

    All retinal disorders, regardless of their aetiology, involve the activation of oxidative stress and apoptosis pathways. The administration of neuroprotective factors is crucial in all phases of the pathology, even when vision has been completely lost. The retina is one of the most susceptible tissues to reactive oxygen species damage. On the other hand, proper development and functioning of the retina requires a precise balance between the processes of proliferation, differentiation and programmed cell death. The life-or-death decision seems to be the result of a complex balance between pro- and anti-apoptotic signals. It has been recently shown the efficacy of natural products to slow retinal degenerative process through different pathways. In this review, we assess the neuroprotective effect of two compounds used in the ancient pharmacopoeia. On one hand, it has been demonstrated that administration of the saffron constituent safranal to P23H rats, an animal model of retinitis pigmentosa, preserves photoreceptor morphology and number, the capillary network and the visual response. On the other hand, it has been shown that systemic administration of tauroursodeoxycholic acid (TUDCA), the major component of bear bile, to P23H rats preserves cone and rod structure and function, together with their contact with postsynaptic neurons. The neuroprotective effects of safranal and TUDCA make these compounds potentially useful for therapeutic applications in retinal degenerative diseases.

  10. Natural Compounds from Saffron and Bear Bile Prevent Vision Loss and Retinal Degeneration

    Directory of Open Access Journals (Sweden)

    Laura Fernández-Sánchez

    2015-07-01

    Full Text Available All retinal disorders, regardless of their aetiology, involve the activation of oxidative stress and apoptosis pathways. The administration of neuroprotective factors is crucial in all phases of the pathology, even when vision has been completely lost. The retina is one of the most susceptible tissues to reactive oxygen species damage. On the other hand, proper development and functioning of the retina requires a precise balance between the processes of proliferation, differentiation and programmed cell death. The life-or-death decision seems to be the result of a complex balance between pro- and anti-apoptotic signals. It has been recently shown the efficacy of natural products to slow retinal degenerative process through different pathways. In this review, we assess the neuroprotective effect of two compounds used in the ancient pharmacopoeia. On one hand, it has been demonstrated that administration of the saffron constituent safranal to P23H rats, an animal model of retinitis pigmentosa, preserves photoreceptor morphology and number, the capillary network and the visual response. On the other hand, it has been shown that systemic administration of tauroursodeoxycholic acid (TUDCA, the major component of bear bile, to P23H rats preserves cone and rod structure and function, together with their contact with postsynaptic neurons. The neuroprotective effects of safranal and TUDCA make these compounds potentially useful for therapeutic applications in retinal degenerative diseases.

  11. Overcoming Multidrug Resistance in Human Cancer Cells by Natural Compounds

    Directory of Open Access Journals (Sweden)

    Tomohiro Nabekura

    2010-05-01

    Full Text Available Multidrug resistance is a phenomenon whereby tumors become resistant to structurally unrelated anticancer drugs. P-glycoprotein belongs to the large ATP-binding cassette (ABC transporter superfamily of membrane transport proteins. P-glycoprotein mediates resistance to various classes of anticancer drugs including vinblastine, daunorubicin, and paclitaxel, by actively extruding the drugs from the cells. The quest for inhibitors of anticancer drug efflux transporters has uncovered natural compounds, including (--epigallocatechin gallate, curcumin, capsaicin, and guggulsterone, as promising candidates. In this review, studies on the effects of natural compounds on P-glycoprotein and anticancer drug efflux transporters are summarized.

  12. The catechin flavonoid reduces proliferation and induces apoptosis of murine lymphoma cells LB02 through modulation of antiapoptotic proteins

    Directory of Open Access Journals (Sweden)

    Daniela Laura Papademetrio

    2013-03-01

    Full Text Available Flavonoids are products of secondary metabolism of plants. They are present in herbs and trees and also act as natural chemopreventives and anticancer agents. Ligaria cuneifolia (Ruiz & Pav. Tiegh., Loranthaceae, is a hemiparasite species that belongs to Argentine flora. Phytochemical studies have disclosed the presence of quercetin, catechin-4β-ol and pro-anthocyanidine as polyphenolic compounds in the active extracts. We previously demonstrated that ethyl acetate extract was capable of reducing cell proliferation and inducing apoptotic death of lymphoid tumor cells. The aim of the current study is to determine whether or not catechin, isolated from L. cuneifolia extracts can induce leukemia cell death and to determine its effect on the cytoplasmatic proteins that modulate cell survival. Our results show that catechin can reduce proliferation of murine lymphoma cell line LB02. The effect is mediated by apoptosis at concentrations upper to 100 µg/mL. Cell death is related to the loss of mitochondrial membrane potential (ΔΨm and a down regulation of survivin and Bcl-2 together with the increase of pro-apoptotic protein Bax. In summary, the current study indicates that catechin present in the extract of L. cuneifolia is in part, responsible for the anti-proliferative activity of whole extracts by induction of ΔΨm disruption and modulation of the anti-apoptotic proteins over expressed in tumor cells. These results give new findings into the potential anticancer and chemopreventive activities of L. cuneifolia.

  13. The catechin flavonoid reduces proliferation and induces apoptosis of murine lymphoma cells LB02 through modulation of antiapoptotic proteins

    Directory of Open Access Journals (Sweden)

    Daniela Laura Papademetrio

    2013-06-01

    Full Text Available Flavonoids are products of secondary metabolism of plants. They are present in herbs and trees and also act as natural chemopreventives and anticancer agents. Ligaria cuneifolia (Ruiz & Pav. Tiegh., Loranthaceae, is a hemiparasite species that belongs to Argentine flora. Phytochemical studies have disclosed the presence of quercetin, catechin-4β-ol and pro-anthocyanidine as polyphenolic compounds in the active extracts. We previously demonstrated that ethyl acetate extract was capable of reducing cell proliferation and inducing apoptotic death of lymphoid tumor cells. The aim of the current study is to determine whether or not catechin, isolated from L. cuneifolia extracts can induce leukemia cell death and to determine its effect on the cytoplasmatic proteins that modulate cell survival. Our results show that catechin can reduce proliferation of murine lymphoma cell line LB02. The effect is mediated by apoptosis at concentrations upper to 100 µg/mL. Cell death is related to the loss of mitochondrial membrane potential (ΔΨm and a down regulation of survivin and Bcl-2 together with the increase of pro-apoptotic protein Bax. In summary, the current study indicates that catechin present in the extract of L. cuneifolia is in part, responsible for the anti-proliferative activity of whole extracts by induction of ΔΨm disruption and modulation of the anti-apoptotic proteins over expressed in tumor cells. These results give new findings into the potential anticancer and chemopreventive activities of L. cuneifolia.

  14. STAT4-associated natural killer cell tolerance following liver transplantation.

    Science.gov (United States)

    Jamil, K M; Hydes, T J; Cheent, K S; Cassidy, S A; Traherne, J A; Jayaraman, J; Trowsdale, J; Alexander, G J; Little, A-M; McFarlane, H; Heneghan, M A; Purbhoo, M A; Khakoo, S I

    2017-02-01

    Natural killer (NK) cells are important mediators of liver inflammation in chronic liver disease. The aim of this study was to investigate why liver transplants (LTs) are not rejected by NK cells in the absence of human leukocyte antigen (HLA) matching, and to identify a tolerogenic NK cell phenotype. Phenotypic and functional analyses on NK cells from 54 LT recipients were performed, and comparisons made with healthy controls. Further investigation was performed using gene expression analysis and donor:recipient HLA typing. NK cells from non-HCV LT recipients were hypofunctional, with reduced expression of NKp46 (p<0.05) and NKp30 (p<0.001), reduced cytotoxicity (p<0.001) and interferon (IFN)-γ secretion (p<0.025). There was no segregation of this effect with HLA-C, and these functional changes were not observed in individuals with HCV. Microarray and RT-qPCR analysis demonstrated downregulation of STAT4 in NK cells from LT recipients (p<0.0001). Changes in the expression levels of the transcription factors Helios (p=0.06) and Hobit (p=0.07), which control NKp46 and IFNγ expression, respectively, were also detected. Hypofunctionality of NK cells was associated with impaired STAT4 phosphorylation and downregulation of the STAT4 target microRNA-155. Conversely in HCV-LT NK cell tolerance was reversed, consistent with the more aggressive outcome of LT for HCV. LT is associated with transcriptional and functional changes in NK cells, resulting in reduced activation. NK cell tolerance occurs upstream of major histocompatibility complex (MHC) class I mediated education, and is associated with deficient STAT4 phosphorylation. STAT4 therefore represents a potential therapeutic target to induce NK cell tolerance in liver disease. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  15. Inactivation of the forkhead transcription factor FoxO3 is essential for PKB-mediated survival of hematopoietic progenitor cells by kit ligand

    DEFF Research Database (Denmark)

    Engström, Maria; Karlsson, Richard; Jönsson, Jan-Ingvar

    2003-01-01

    OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation of phosphatidylinos......OBJECTIVE: Kit ligand (KL) is a major survival factor for hematopoietic stem cells. Although anti-apoptotic bcl-2 family members are expressed in these cells, the survival effects by KL appear to involve other mechanisms. Survival signals can also be elicited by the activation......, immunofluorescence, and subcellular fractionation, we analyzed the effects of KL on PKB and different forkhead family members in two factor-dependent cell lines, FDCP-mix and FDC-P1, as well as primary mouse bone marrow-derived Lin(-) progenitors. Forced overexpression of triple mutated form of FoxO3 by retroviral...

  16. A Case of Mature Natural Killer-Cell Neoplasm Manifesting Multiple Choroidal Lesions: Primary Intraocular Natural Killer-Cell Lymphoma

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    Yoshiaki Tagawa

    2015-11-01

    Full Text Available Purpose: Natural killer (NK cell neoplasm is a rare disease that follows an acute course and has a poor prognosis. It usually emerges from the nose and appears in the ocular tissue as a metastasis. Herein, we describe a case of NK-cell neoplasm in which the eye was considered to be the primary organ. Case: A 50-year-old female displayed bilateral anterior chamber cells, vitreous opacity, bullous retinal detachment, and multiple white choroidal mass lesions. Although malignant lymphoma or metastatic tumor was suspected, various systemic examinations failed to detect any positive results. A vitrectomy was performed OS; however, histocytological analyses from the vitreous sample showed no definite evidence of malignancy, and IL-10 concentration was low. Enlarged choroidal masses were fused together. Three weeks after the first visit, the patient suddenly developed an attack of fever, night sweat, and hepatic dysfunction, and 5 days later, she passed away due to multiple organ failure. Immunohistochemisty and in situ hybridization revealed the presence of atypical cells positive for CD3, CD56, and Epstein-Barr virus-encoded RNAs, resulting in the diagnosis of NK-cell neoplasm. With the characteristic clinical course, we concluded that this neoplasm was a primary intraocular NK-cell lymphoma. Conclusions: This is the first report to describe primary intraocular NK-cell neoplasm. When we encounter atypical choroidal lesions, we should consider the possibility of NK-cell lymphoma, even though it is a rare disease.

  17. Natural dyes as photosensitizers for dye-sensitized solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Hao, Sancun; Wu, Jihuai; Huang, Yunfang; Lin, Jianming [Institute of Materials Physical Chemistry, Huaqiao University, Quanzhou, Fujian 362021 (China)

    2006-02-15

    The dye-sensitized solar cells (DSC) were assembled by using natural dyes extracted from black rice, capsicum, erythrina variegata flower, rosa xanthina, and kelp as sensitizers. The I{sub SC} from 1.142mA to 0.225mA, the V{sub OC} from 0.551V to 0.412V, the fill factor from 0.52 to 0.63, and P{sub max} from 58{mu}W to 327{mu}W were obtained from the DSC sensitized with natural dye extracts. In the extracts of natural fruit, leaves and flower chosen, the black rice extract performed the best photosensitized effect, which was due to the better interaction between the carbonyl and hydroxyl groups of anthocyanin molecule on black rice extract and the surface of TiO{sub 2} porous film. The blue-shift of absorption wavelength of the black rice extract in ethanol solution on TiO{sub 2} film and the blue-shift phenomenon from absorption spectrum to photoaction spectrum of DSC sensitized with black rice extract are discussed in the paper. Because of the simple preparation technique, widely available and low cheap cost natural dye as an alternative sensitizer for dye-sensitized solar cell is promising. (author)

  18. In vitro protective effects of Thymus quinquecostatus Celak extracts on t-BHP-induced cell damage through antioxidant activity.

    Science.gov (United States)

    Kim, Yon-Suk; Lee, Seung-Jae; Hwang, Jin-Woo; Kim, Eun-Kyung; Kim, Seong-Eun; Kim, Ee-Hwa; Moon, Sang-Ho; Jeon, Byung-Tae; Park, Pyo-Jam

    2012-11-01

    The purpose of this study was to evaluate the antioxidative activities of water and 70% ethanolic extracts from the Thymus quinquecostatus Celak (TQC) for natural antioxidant source. The antioxidant activities were compared with other natural and synthetic antioxidants. The levels of total polyphenols and flavonoids were also determined. The extracts were found to have different levels of antioxidant properties in a few kind of assay. The results showed that higher radical scavenging activity, reducing power and antioxidant capacity in FRAP than those of BHT as a positive control. In addition, the extracts from the TQC leaf and stem showed stronger antioxidant activity than that of vitamin C, α-tocopherol in ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Cytoprotective and anti-apoptotic effect of water extracts from TQC was also prevented t-BHP-induced toxicity in Chang liver cells. Therefore, these results indicate that TQC extracts have antioxidant properties through its ability to enhance the cell viability, reduction of production of ROS, inhibition of oxidative damage, mitochondria dysfunction and ultimately inhibition of cell apoptosis. Based on the results described above, it is suggested that TQC has the potential to protect liver on t-BHP-induced cell damage and should be considered as a prospective functional food. Copyright © 2012 Elsevier Ltd. All rights reserved.

  19. Vorinostat and metformin sensitize EGFR-TKI resistant NSCLC cells via BIM-dependent apoptosis induction.

    Science.gov (United States)

    Chen, Hengyi; Wang, Yubo; Lin, Caiyu; Lu, Conghua; Han, Rui; Jiao, Lin; Li, Li; He, Yong

    2017-11-07

    There is a close relationship between low expression of BIM and resistance to epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). Vorinostat is a pan-histone deacetylase inhibitor (HDACi) that augments BIM expression in various types of tumor cells, however, this effect is attenuated by the high expression of anti-apoptotic proteins in EGFR-TKI resistant non-small cell lung cancer (NSCLC) cells. Vorinostat in combination with metformin - a compound that can inhibit anti-apoptotic proteins expression, might cooperate to activate apoptotic signaling and overcome EGFR-TKI resistance. This study aimed to investigate the cooperative effect and evaluate possible molecular mechanisms. The results showed that vorinostat combined with gefitinib augmented BIM expression and increased the sensitivity of EGFR-TKI resistant NSCLC cells to gefitinib, adding metformin simultaneously could obviously inhibit the expression of anti-apoptotic proteins, and further increased expression levels of BIM and BAX, and as a result, further improved the sensitivity of gefitinib both on the NSCLC cells with intrinsic and acquired resistance to EGFR-TKI. In addition, autophagy induced by gefitinib and vorinostat could be significantly suppressed by metformin, which might also contribute to enhance apoptosis and improve sensitivity of gefitinib. These results suggested that the combination of vorinostat and metformin might represent a novel strategy to overcome EGFR-TKI resistance associated with BIM-dependent apoptosis in larger heterogeneous populations.

  20. Recognition of microbial glycolipids by Natural Killer T cells

    Directory of Open Access Journals (Sweden)

    Dirk Michael Zajonc

    2015-08-01

    Full Text Available T cells can recognize microbial antigens when presented by dedicated antigen-presenting molecules. While peptides are presented by classical members of the Major Histocompatibility (MHC family (MHC I and II, lipids, glycolipids and lipopeptides can be presented by the non-classical MHC member CD1. The best studied subset of lipid-reactive T cells are Type I Natural killer T (iNKT cells that recognize a variety of different antigens when presented by the non-classical MHCI homolog CD1d. iNKT cells have been shown to be important for the protection against various microbial pathogens, including B. burgdorferi the causative agents of Lyme disease and S. pneumoniae, which causes pneumococcal meningitis and community-acquired pneumonia. Both pathogens carry microbial glycolipids that can trigger the T cell antigen receptor (TCR, leading to iNKT cell activation. iNKT cells have an evolutionary conserved TCR alpha chain, yet retain the ability to recognize structurally diverse glycolipids. They do so using a conserved recognition mode, in which the TCR enforces a conserved binding orientation on CD1d. TCR binding is accompanied by structural changes within the TCR binding site of CD1d, as well as the glycolipid antigen itself. In addition to direct recognition of microbial antigens, iNKT cells can also be activated by a combination of cytokines (IL-12/IL-18 and TCR stimulation. Many microbes carry TLR antigens and microbial infections can lead to TLR activation. The subsequent cytokine response in turn lower the threshold of TCR mediated iNKT cell activation, especially when weak microbial or even self-antigens are presented during the cause of the infection. In summary, iNKT cells can be directly activated through TCR triggering of strong antigens, while cytokines produced by the innate immune response may be necessary for TCR triggering and iNKT cell activation in the presence of weak antigens. Here we will review the molecular basis of iNKT cell

  1. Myeloid-derived suppressor cells restrain Natural Killer cell activity in CVB3 myocarditis

    OpenAIRE

    Holz, Lisa Maria

    2017-01-01

    Murine models of coxsackievirus B3 (CVB3) induced myocarditis (with host specific outcomes), represent different outcome of myocarditis, ranging from virus elimination and complete recovery in resistant C57BL/6J mice to virus persistence and chronic myocarditis in susceptible A.BY/SnJ mice. In previous experiments, we found that Natural Killer cells (NK cells) positively influence the outcome of CVB3 myocarditis in mice. Myeloid-derived suppressor cells (MDSC) are potent inhibitors of the inn...

  2. Photovoltaic characteristics of natural light harvesting dye sensitized solar cells

    Science.gov (United States)

    Hafez, H. S.; Shenouda, S. S.; Fadel, M.

    2018-03-01

    In this work of research, anthocyanin as a natural dye obtained from raspberry fruits, was used and tested as a photon harvesting/electron donating dye in titanium dioxide nanoparticle-based DSSCs. A working photoelectrode made from TiO2 nanoparticles with an average particle size (10-40 nm) that is coated on Florine doped tin-oxide substrate, was prepared via a simple and low cost hydrothermal method. A detailed structural and morphological analysis of the TiO2 photoactive electrode was investigated by X-ray diffraction (XRD), diffuse reflectance spectrometer, transmission electron microscope (TEM) and scanning electron microscope (SEM). Complete photovoltaic characteristics including (current, voltage, outpower, and responsivity) of the natural anthocyanin based dye sensitized solar cell have been investigated under different illumination intensity ranging from 10 to 100 mW.cm- 2. The cell responsivity and efficiency of the fabricated solar cell under different illumination intensity were found to be in the range (R = 15.6-23.8 mA.W- 1 and η = 0.13-0.25) at AM = 1.5 conditions. This study is important for enhancing the future applications of the promising DSSC technology.

  3. IL-15 STIMULATED NATURAL KILLER CELLS CLEAR HIV-1 INFECTED CELLS FOLLOWING LATENCY REVERSAL EX VIVO.

    Science.gov (United States)

    Garrido, Carolina; Abad-Fernandez, Maria; Tuyishime, Marina; Pollara, Justin J; Ferrari, Guido; Soriano-Sarabia, Natalia; Margolis, David M

    2018-03-28

    Current efforts towards HIV eradication include approaches to augment immune recognition and elimination of persistently infected cells following latency reversal. Natural killer (NK) cells, the main effectors of the innate immune system, recognize and clear targets using different mechanisms than CD8 + T cells, offering an alternative or complementary approach for HIV clearance strategies. We assessed the impact of IL-15 treatment on NK cell function and the potential of stimulated NK cells to clear the HIV reservoir. We measured NK cell receptor expression, antibody-dependent cell-dependent cytotoxicity (ADCC), cytotoxicity, IFN-γ production and antiviral activity in autologous HIV replication systems. All NK cell functions were uniformly improved by IL-15, and more importantly, IL-15-treated NK cells were able to clear latently HIV infected cells after exposure to vorinostat, a clinically relevant latency reversing agent. We also demonstrate that NK cells from HIV infected individuals aviremic on antiretroviral therapy can be efficiently stimulated with IL-15. Our work opens a promising line of investigation towards future immunotherapies to clear persistent HIV infection using NK cells. IMPORTANCE In the search for an HIV cure, strategies to enhance immune function to allow recognition and clearance of HIV infected cells following latency reversal are being evaluated. Natural killer (NK) cells possess characteristics that can be exploited for immunotherapy against persistent HIV infection. We demonstrate that NK cells from HIV-positive donors can be strongly stimulated with IL-15, improving their antiviral and cytotoxic potential, and more importantly, clearing HIV infected cells after latency reversal with a clinically relevant drug. Our results encourage further investigation to design NK cell-based immunotherapies to achieve HIV eradication. Copyright © 2018 American Society for Microbiology.

  4. Psychosocial resources, aging, and natural killer cell terminal maturity.

    Science.gov (United States)

    Segerstrom, Suzanne C; Al-Attar, Ahmad; Lutz, Charles T

    2012-12-01

    Psychosocial factors may influence aspects of immunological aging. The present study tested the hypothesis that psychosocial resources correlate with the expression of the cell surface maker CD57 on natural killer (NK) immune cells. CD57 is a marker of terminal maturation and senescence in this cell subset. The study further tested the relative contribution of specific resources in the social, psychological, financial, and status-skill domains, given the potential differential value of different resources for younger and older adults, and the contribution of relative versus absolute resources. Younger (n = 38) and older (n = 34) women completed measures of relative and absolute resources and had blood drawn. Examined both between groups and within the older women, older age and fewer total relative resources were associated with more CD57 expression on NK cells. One SD in resources was the equivalent of 5 years of aging among the older women. Among the specific resource types, a preponderance of financial resources, both relative and absolute, was associated with less CD57 expression on NK cells, and these relationships did not significantly vary between younger and older women. There was no evidence that depressive symptoms mediated the effects of resources on CD57 expression on NK cells. These findings provide support for the hypothesis that the sense that one has substantial resources, particularly with regard to finances and possessions, may retard age-associated aspects of the microenvironment in which NK cells develop and mature, independent of effects on distress, and this process may begin in younger adulthood. 2013 APA, all rights reserved

  5. Hepatic natural killer cells exclusively kill splenic/blood natural killer-resistant tumor cells by the perforin/granzyme pathway

    NARCIS (Netherlands)

    Vermijlen, David; Luo, Dianzhong; Froelich, Christopher J.; Medema, Jan Paul; Kummer, Jean Alain; Willems, Erik; Braet, Filip; Wisse, Eddie

    2002-01-01

    Hepatic natural killer (NK) cells are located in the liver sinusoids adherent to the endothelium. Human and rat hepatic NK cells induce cytolysis in tumor cells that are resistant to splenic or blood NK cells. To investigate the mechanism of cell death, we examined the capacity of isolated, pure

  6. Cytokine-induced killer cells are type II natural killer T cells

    Directory of Open Access Journals (Sweden)

    Schmidt-Wolf, Ingo G.H.

    2007-09-01

    Full Text Available Background: Until now, cytokine-induced killer (CIK cells were assumed to be part of the type I natural killer T (NKT cell population, but it was not yet investigated if this is correct. Methods: For analysis, CIK cells were generated by various culture conditions. Human type I NKT cells express a T cell receptor (TCR composed of an invariant Vα24-JαQ chain combined with one of several Vβ chains. The Vα24 is a reliable marker for the presence of these TCRs. Results: While comparing cultures stimulated with different substances, we observed the lack of any Vα24 on the surface of CIK culture cells. Conclusion: We conclude that CIK cells do not belong to the type I NKT cells.

  7. Cancer immunosurveillance and immunoediting by natural killer cells.

    Science.gov (United States)

    Gross, Emilie; Sunwoo, John B; Bui, Jack D

    2013-01-01

    Cancer immunosurveillance eradicates certain neoplasms, but the selective pressure exerted by this active surveillance leads to the emergence of immune evasive tumor clones in a process called cancer immunoediting. Natural killer (NK) cells are potent effectors of cancer immunoediting and can destroy tumors directly via exocytosis of cytotoxic granules or indirectly by producing interferon γ to activate M1 and TH1 immune responses. This review gathers current knowledge of NK immunosurveillance of primary tumors induced in mice and highlights the importance of NK immunosurveillance for human cancers. Evidence of NK immunoediting, as revealed by studies using NK-deficient models, demonstrates how exposure to NK cells engenders modification of cancer immunogenicity to permit survival and progression of the tumor clone in an immunocompetent environment.

  8. Natural convection cooling of the IFMIF target and test cell

    Energy Technology Data Exchange (ETDEWEB)

    Slobodchuk, V. [Institute for Reactor Safety, Research Centre of Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Stratmanns, E. [Institute for Reactor Safety, Research Centre of Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)], E-mail: stratmanns@irs.fzk.de; Gordeev, S.; Heinzel, V.; Leichtle, D. [Institute for Reactor Safety, Research Centre of Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Moeslang, A. [Institute for Material Research I, Research Centre of Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany); Simakov, S.P. [Institute for Reactor Safety, Research Centre of Karlsruhe, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

    2007-10-15

    The present work summarizes efforts on the simulation of natural convection cooling within the IFMIF target and test cell. The simulations have been performed with the STAR-CD code using the k-{omega} high-Reynolds number turbulence model. A dedicated thermohydraulic model has been devised including Lithium loop components. Nuclear heat production has been calculated by the Monte-Carlo code McDeLicious for different parts of the target and test cell walls and was used as input for the STAR-CD simulations. Helium atmospheres at several pressures from 0.1 to 10{sup -5} MPa have been investigated. In order to limit the maximum temperature of the concrete walls to 80 deg. C it was necessary to add thermal insulation layers to the hot Lithium loop surfaces and a conceptual system of two cooling layers in different depths of the concrete walls.

  9. Enhanced transient recombinant protein production in CHO cells through the co-transfection of the product gene with Bcl-xL

    Science.gov (United States)

    Zustiak, Matthew P.; Jose, Lisa; Xie, Yueqing; Zhu, Jianwei; Betenbaugh, Micheal J.

    2014-01-01

    Transient gene expression is gaining popularity as a method to rapidly produce recombinant proteins in mammalian cells. Although significant improvements have been made, in terms of expression, more improvements are needed to compete with the yields achievable in stable gene expression. Much progress has come from optimization of transfection media and parameters, as well as altering culturing conditions to enhance productivity. Recent studies have included using cell lines engineered for apoptosis resistance through the constitutive expression of an anti-apoptotic protein, Bcl-xL. In this study we examine an alternative method of using the benefits of anti-apoptotic gene expression to enhance the transient expression of biotherapeutics, namely, through the co-transfection of bcl-xL and the product-coding gene. CHO-S cells were co-transfected with the product-coding gene and a vector containing Bcl-xL using polyethylenimine. Cells co-transfected with Bcl-xL showed reduced levels of apoptosis, increased specific productivity, and an overall increase in product yield of approximately 100%. Similar results were produced by employing another anti-apoptotic protein, Bcl-2 delta in CHO cells, or through the co-transfection with bcl-xL using HEK-293E cells. This work provides an alternative method for increasing yields of therapeutic proteins in TGE applications without generating a prior stable cell line and subsequent screening which are both time and resource consuming. PMID:24604826

  10. Lactic Acid Bacteria from Kefir Increase Cytotoxicity of Natural Killer Cells to Tumor Cells.

    Science.gov (United States)

    Yamane, Takuya; Sakamoto, Tatsuji; Nakagaki, Takenori; Nakano, Yoshihisa

    2018-03-27

    The Japanese fermented beverage, homemade kefir, contains six lactic acid bacteria: Lactococcus. lactis subsp. Lactis , Lactococcus . lactis subsp. Cremoris , Lactococcus. Lactis subsp. Lactis biovar diacetylactis , Lactobacillus plantarum , Leuconostoc meseuteroides subsp. Cremoris and Lactobacillus casei . In this study, we found that a mixture of the six lactic acid bacteria from kefir increased the cytotoxicity of human natural killer KHYG-1 cells to human chronic myelogenous leukemia K562 cells and colorectal tumor HCT116 cells. Furthermore, levels of mRNA expression and secretion of IFN-γ (interferon gamma) increased in KHYG-1 cells that had been treated with the six lactic acid bacteria mixture from kefir. The results suggest that the six lactic acid bacteria mixture from kefir has strong effects on natural immunity and tumor cell cytotoxicity.

  11. Induced Pluripotent Stem Cell-Derived Natural Killer Cells for Treatment of Ovarian Cancer.

    Science.gov (United States)

    Hermanson, David L; Bendzick, Laura; Pribyl, Lee; McCullar, Valarie; Vogel, Rachel Isaksson; Miller, Jeff S; Geller, Melissa A; Kaufman, Dan S

    2016-01-01

    Natural killer (NK) cells can provide effective immunotherapy for ovarian cancer. Here, we evaluated the ability of NK cells isolated from peripheral blood (PB) and NK cells derived from induced pluripotent stem cell (iPSC) to mediate killing of ovarian cancer cells in a mouse xenograft model. A mouse xenograft model was used to evaluate the intraperitoneal delivery of three different NK cell populations: iPSC-derived NK cells, PB-NK cells that had been activated and expanded in long-term culture, and overnight activated PB-NK cells that were isolated through CD3/CD19 depletion of PB B and T cells. Bioluminescent imaging was used to monitor tumor burden of luciferase expressing tumor lines. Tumors were allowed to establish prior to administering NK cells via intraperitoneal injection. These studies demonstrate a single dose of any of the three NK cell populations significantly reduced tumor burden. When mice were given three doses of either iPSC-NK cells or expanded PB-NK cells, the median survival improved from 73 days in mice untreated to 98 and 97 days for treated mice, respectively. From these studies, we conclude iPSC-derived NK cells mediate antiovarian cancer killing at least as well as PB-NK cells, making these cells a viable resource for immunotherapy for ovarian cancer. Due to their ability to be easily differentiated into NK cells and their long-term expansion potential, iPSCs can be used to produce large numbers of well-defined NK cells that can be banked and used to treat a large number of patients including treatment with multiple doses if necessary. © 2015 AlphaMed Press.

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

    Science.gov (United States)

    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

  13. Synergistic effects of coralyne and paclitaxel on cell migration and proliferation of breast cancer cells lines.

    Science.gov (United States)

    Kumari, Seema; Badana, Anil Kumar; Mohan, G Murali; Shailender Naik, G; Malla, RamaRao

    2017-07-01

    Breast cancer is one of the most frequently diagnosed cancer in woman. Triple-negative breast cancer (TNBC) is most aggressive form of breast cancer. There is a growing interest in the use of natural products in combinational chemotherapy to improve the effectiveness in combating proliferation of cancer cells. Here, we hypothesized that coralyne in combination with paclitaxel may exhibit synergistic effect on inhibition of proliferation, migration and induction of apoptosis in MCF-7 and MDA-MB-231 breast cancer cell lines. MTT and BrdU incorporation assays were performed to study the effect of drugs alone and in combination on cell cytotoxicity and proliferation of the breast cancer cell lines, respectively. Adhesion and wound healing assays were performed to study the cell and extracellular matrix interactions. In addition, expression of proliferation marker ki-67 and apoptotic markers Bax and Bcl-2 was determined to study the effect of coralyne in combination with paclitaxel by reverse transcriptase PCR and confirmed by Western blot. The results indicated the synergism between coralyne and paclitaxel on proliferation and migration of breast cancer cell lines. This study also showed that combinational drug treatment decreased the expression of ki-67 and there was an increase in pro apoptotic factor Bax with decreased in expression of anti-apoptotic factor Bcl-2 in breast cancer cell lines with negligible effect on normal breast cell line. Overall, our data described the promising therapeutic potential of coralyne in combination with paclitaxel in treating breast cancer at lower effective dose. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  14. Comparative genomics of natural killer cell receptor gene clusters.

    Directory of Open Access Journals (Sweden)

    James Kelley

    2005-08-01

    Full Text Available Many receptors on natural killer (NK cells recognize major histocompatibility complex class I molecules in order to monitor unhealthy tissues, such as cells infected with viruses, and some tumors. Genes encoding families of NK receptors and related sequences are organized into two main clusters in humans: the natural killer complex on Chromosome 12p13.1, which encodes C-type lectin molecules, and the leukocyte receptor complex on Chromosome 19q13.4, which encodes immunoglobulin superfamily molecules. The composition of these gene clusters differs markedly between closely related species, providing evidence for rapid, lineage-specific expansions or contractions of sets of loci. The choice of NK receptor genes is polarized in the two species most studied, mouse and human. In mouse, the C-type lectin-related Ly49 gene family predominates. Conversely, the single Ly49 sequence is a pseudogene in humans, and the immunoglobulin superfamily KIR gene family is extensive. These different gene sets encode proteins that are comparable in function and genetic diversity, even though they have undergone species-specific expansions. Understanding the biological significance of this curious situation may be aided by studying which NK receptor genes are used in other vertebrates, especially in relation to species-specific differences in genes for major histocompatibility complex class I molecules.

  15. Terminalia Chebula provides protection against dual modes of necroptotic and apoptotic cell death upon death receptor ligation.

    Science.gov (United States)

    Lee, Yoonjung; Byun, Hee Sun; Seok, Jeong Ho; Park, Kyeong Ah; Won, Minho; Seo, Wonhyoung; Lee, So-Ra; Kang, Kidong; Sohn, Kyung-Cheol; Lee, Ill Young; Kim, Hyeong-Geug; Son, Chang Gue; Shen, Han-Ming; Hur, Gang Min

    2016-04-27

    Death receptor (DR) ligation elicits two different modes of cell death (necroptosis and apoptosis) depending on the cellular context. By screening a plant extract library from cells undergoing necroptosis or apoptosis, we identified a water extract of Terminalia chebula (WETC) as a novel and potent dual inhibitor of DR-mediated cell death. Investigation of the underlying mechanisms of its anti-necroptotic and anti-apoptotic action revealed that WETC or its constituents (e.g., gallic acid) protected against tumor necrosis factor-induced necroptosis via the suppression of TNF-induced ROS without affecting the upstream signaling events. Surprisingly, WETC also provided protection against DR-mediated apoptosis by inhibition of the caspase cascade. Furthermore, it activated the autophagy pathway via suppression of mTOR. Of the WETC constituents, punicalagin and geraniin appeared to possess the most potent anti-apoptotic and autophagy activation effect. Importantly, blockage of autophagy with pharmacological inhibitors or genetic silencing of Atg5 selectively abolished the anti-apoptotic function of WETC. These results suggest that WETC protects against dual modes of cell death upon DR ligation. Therefore, WETC might serve as a potential treatment for diseases characterized by aberrantly sensitized apoptotic or non-apoptotic signaling cascades.

  16. Revving up natural killer cells and cytokine-induced killer cells against hematological malignancies

    Directory of Open Access Journals (Sweden)

    Gianfranco ePittari

    2015-05-01

    Full Text Available 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 (KIR, 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.

  17. Suppression of Natural Killer Cell Activity by Regulatory NKT10 Cells Aggravates Alcoholic Hepatosteatosis

    Directory of Open Access Journals (Sweden)

    Kele Cui

    2017-10-01

    Full Text Available We and others have found that the functions of hepatic natural killer (NK cells are inhibited but invariant NKT (iNKT cells become activated after alcohol drinking, leaving a possibility that there exists interplay between NK cells and iNKT cells during alcoholic liver disease. Here, in a chronic plus single-binge ethanol consumption mouse model, we observed that NK cells and interferon-γ (IFN-γ protected against ethanol-induced liver steatosis, as both wild-type (WT mice treated with anti-asialo GM1 antibody and IFN-γ-deficient GKO mice developed more severe alcoholic fatty livers. As expected, IFN-γ could directly downregulate lipogenesis in primary hepatocytes in vitro. On the contrary, iNKT cell-deficient Jα18−/− or interleukin-10 (IL-10−/− mice showed fewer alcoholic steatosis, along with the recovered number and IFN-γ release of hepatic NK cells, and exogenous IL-10 injection was sufficient to compensate for iNKT cell deficiency. Furthermore, NK cell depletion in Jα18−/− or IL-10−/− mice caused more severe hepatosteatosis, implying NK cells are the direct effector cells to inhibit liver steatosis. Importantly, adoptive transfer of iNKT cells purified from normal but not IL-10−/− mice resulted in suppression of the number and functions of NK cells and aggravated alcoholic liver injury in Jα18−/− mice, indicating that IL-10-producing iNKT (NKT10 cells are the regulators on NK cells. Conclusion: Ethanol exposure-triggered NKT10 cells antagonize the protective roles of NK cells in alcoholic hepatosteatosis.

  18. Escin induces apoptosis in human renal cancer cells through G2/M arrest and reactive oxygen species-modulated mitochondrial pathways.

    Science.gov (United States)

    Yuan, Sheau-Yun; Cheng, Chen-Li; Wang, Shian-Shiang; Ho, Hao-Chung; Chiu, Kun-Yuan; Chen, Chuan-Shu; Chen, Cheng-Che; Shiau, Ming-Yuh; Ou, Yen-Chuan

    2017-02-01

    Escin, a natural pentacyclic triterpenoid compound, exhibits antitumor effects on various types of human cancer cells, but its effect on human renal cancer cells has not been fully elucidated. In the present study, we demonstrated that escin elicits cytotoxic effects on human renal cancer cells (786-O and Caki-1) in a dose-dependent manner, as determined by MTT assay. Escin induced G2/M arrest, and then increased the sub-G1 population, Annexin V binding, activation of caspase-9/-3, cleavage of poly(ADP-ribose) polymerase (PARP) and Bax protein. Escin also decreased the anti-apoptotic protein levels of Bcl-2, X-linked inhibitor of apoptosis protein and survivin. In addition, escin induced reactive oxygen species (ROS) generation, leading to mitochondrial membrane potential dysfunction and inducing apoptosis in 786-O renal cancer cells, which were suppressed by antioxidants, such as NAC. Collectively, our results suggest that escin induces apoptosis via the intrinsic-mitochondrial apoptosis pathway through G2/M arrest and ROS generation in human renal cancer cells. Escin appears to have potential as a clinically useful chemotherapeutic agent for human renal cancer.

  19. Natural Killer Cell Response to Chemotherapy-Stressed Cancer Cells: Role in Tumor Immunosurveillance

    Directory of Open Access Journals (Sweden)

    Alessandra Zingoni

    2017-09-01

    Full Text Available Natural killer (NK cells are innate cytotoxic lymphoid cells that actively prevent neoplastic development, growth, and metastatic dissemination in a process called cancer immunosurveillance. An equilibrium between immune control and tumor growth is maintained as long as cancer cells evade immunosurveillance. Therapies designed to kill cancer cells and to simultaneously sustain host antitumor immunity are an appealing strategy to control tumor growth. Several chemotherapeutic agents, depending on which drugs and doses are used, give rise to DNA damage and cancer cell death by means of apoptosis, immunogenic cell death, or other forms of non-apoptotic death (i.e., mitotic catastrophe, senescence, and autophagy. However, it is becoming increasingly clear that they can trigger additional stress responses. Indeed, relevant immunostimulating effects of different therapeutic programs include also the activation of pathways able to promote their recognition by immune effector cells. Among stress-inducible immunostimulating proteins, changes in the expression levels of NK cell-activating and inhibitory ligands, as well as of death receptors on tumor cells, play a critical role in their detection and elimination by innate immune effectors, including NK cells. Here, we will review recent advances in chemotherapy-mediated cellular stress pathways able to stimulate NK cell effector functions. In particular, we will address how these cytotoxic lymphocytes sense and respond to different types of drug-induced stresses contributing to anticancer activity.

  20. Clinical Relevance of Natural Killer Cells Following Hematopoietic Stem Cell Transplantation

    Directory of Open Access Journals (Sweden)

    Jeanne M Palmer, Kamalakannan Rajasekaran, Monica S Thakar, Subramaniam Malarkannan

    2013-01-01

    Full Text Available Natural killer (NK cells are one of the first cells to recover following allogeneic hematopoietic stem cell transplantation (HSCT, and are believed to play an important role in facilitating engraftment or preventing post-transplant infection and tumor recurrence. Recent studies have provided novel insights into the mechanisms by which NK cells mediate these highly clinically relevant immunological functions. In particular, the ability of NK cells to reduce the risk of graft versus host disease (GVHD and increase the graft versus leukemia effect (GVL in the setting of human leukocyte antigen (HLA-haploidentical HSCT highlights their clinical potentials. NK cells also mediate anti-viral protection, in particular against cytomegalovirus (CMV, an infection that causes significant morbidity and mortality following transplant. Another crucial function of NK cells is providing protection against bacterial infections at the mucosal barriers. NK cells achieve this by promoting anti-microbial defenses and regeneration of epithelial cells. These recent exciting findings provide a strong basis for the formulation of novel NK cell-based immunotherapies. In this review, we summarize the recent advances related to the mechanisms, functions, and future clinical prospects of NK cells that can impact post-transplant outcomes.

  1. Requirement for Interactions of Natural Killer T Cells and Myeloid Derived Suppressor Cells for Transplantation Tolerance

    Science.gov (United States)

    Hongo, David; Tang, Xiaobin; Baker, Jeanette; Engleman, Edgar G.; Strober, Samuel

    2014-01-01

    The goal of the study was to elucidate the cellular and molecular mechanisms by which a clinically applicable immune tolerance regimen of combined bone marrow and heart transplants in mice results in mixed chimerism and graft acceptance. The conditioning regimen of lymphoid irradiation and anti-T cell antibodies changed the balance of cells in the lymphoid tissues to create a tolerogenic microenvironment favoring the increase of natural killer T (NKT) cells, CD4+CD25+ Tregs, and Gr-1+CD11b+ myeloid derived suppressor cells (MDSCs), over conventional T cells. The depletion of MDSCs abrogated chimerism and tolerance, and add back of these purified cells was restorative. The conditioning regimen activated the MDSCs as judged by the increased expression of arginase-1, IL-4Rα, and PDL1, and the activated cells gained the capacity to suppress the proliferation of conventional T cells to alloantigens in the mixed leukocyte reaction. MDSC activation was dependent on the presence of host invariant NKT cells. The conditioning regimen polarized the host invariant NKT cells toward IL-4 secretion, and MDSC activation was dependent on IL-4. In conclusion, there was a requirement for MDSCs for chimerism and tolerance, and their suppressive function was dependent on their interactions with NKT cells and IL-4. PMID:25311657

  2. Human natural killer (NK) cells produce a late-acting B-cell differentiation activity.

    Science.gov (United States)

    Kimata, H; Sherr, E H; Saxon, A

    1988-09-01

    The supernatant of unstimulated purified NKH-1 bearing human natural killer (NK) cells was found to enhance ongoing immunoglobulin synthesis. This NK-Cell supernatant (NKSN) enhanced IgE, IgG, and IgA synthesis from corresponding B-cell lines without increasing thymidine incorporation or cell number. Separation of NKH-1+ cells into CD3- or CD3+ cells showed that this activity was produced by the CD3- population. Recombinant human interleukin (IL)-1, IL-2, IL-4, interferon (INF)-beta 1, INF-gamma, granulocyte-macrophage colony-stimulating factor (GM-CSF), tumor necrosis factor (TNF)-alpha, or partially purified low molecular weight B-cell growth factor (BCGF) failed to provide the same enhancement of Ig synthesis. While the NKSN contained small amounts of IL-6 (0.1 U/ml) and IL-6 could increase Ig synthesis in vitro, the optimal IL-6 enhancement was far less than that observed with NKSN. NKSN also enhanced ongoing Ig synthesis from in vivo activated B cells obtained from peripheral blood or bone marrow but failed to induce Ig synthesis from resting or in vitro activated B cells. These results demonstrate that human NK (CD3-, NKH-1+) cells can produce B-cell differentiation activity capable of regulating Ig production in vivo, which appears to be distinct from the activity of previously described cytokines.

  3. In vivo generation of decidual natural killer cells from resident hematopoietic progenitors

    Science.gov (United States)

    Chiossone, Laura; Vacca, Paola; Orecchia, Paola; Croxatto, Daniele; Damonte, Patrizia; Astigiano, Simonetta; Barbieri, Ottavia; Bottino, Cristina; Moretta, Lorenzo; Mingari, Maria Cristina

    2014-01-01

    Decidual natural killer cells accumulate at the fetal-maternal interface and play a key role in a successful pregnancy. However, their origin is still unknown. Do they derive from peripheral natural killer cells recruited in decidua or do they represent a distinct population that originates in situ? Here, we identified natural killer precursors in decidua and uterus of pregnant mice. These precursors underwent rapid in situ differentiation and large proportions of proliferating immature natural killer cells were present in decidua and uterus as early as gestation day 4.5. Here, we investigated the origin of decidua- and uterus-natural killer cells by performing transfer experiments of peripheral mature natural killer cells or precursors from EGFP+ mice. Results showed that mature natural killer cells did not migrate into decidua and uterus, while precursors were recruited in these organs and differentiated towards natural killer cells. Moreover, decidua- and uterus-natural killer cells displayed unique phenotypic and functional features. They expressed high levels of the activating Ly49D receptor in spite of their immature phenotype. In addition, decidua- and uterus-natural killer cells were poorly cytolytic and produced low amounts of IFN-γ, while they released factors (GM-CSF, VEGF, IP-10) involved in neo-angiogenesis and tissue remodeling. Our data reveal in situ generation of decidual natural killer cells and provide an important correlation between mouse and human decidual natural killer cells, allowing further studies to be carried out on their role in pregnancy-related diseases. PMID:24179150

  4. 7α-Hydroxy-β-Sitosterol from Chisocheton tomentosus Induces Apoptosis via Dysregulation of Cellular Bax/Bcl-2 Ratio and Cell Cycle Arrest by Downregulating ERK1/2 Activation

    Directory of Open Access Journals (Sweden)

    Mohammad Tasyriq

    2012-01-01

    Full Text Available In continuation of our interest towards the elucidation of apoptotic pathways of cytotoxic phytocompounds, we have embarked upon a study on the anticancer effects of 7α-hydroxy-β-sitosterol (CT1, a rare natural phytosterol oxide isolated from Chisocheton tomentosus. CT1 was found to be cytotoxic on three different human tumor cell lines with minimal effects on normal cell controls, where cell viability levels were maintained ≥80% upon treatment. Our results showed that cell death in MCF-7 breast tumor cells was achieved through the induction of apoptosis via downregulation of the ERK1/2 signaling pathway. CT1 was also found to increase proapoptotic Bax protein levels, while decreasing anti-apoptotic Bcl-2 protein levels, suggesting the involvement of the intrinsic pathway. Reduced levels of initiator procaspase-9 and executioner procaspase-3 were also observed following CT1 exposure, confirming the involvement of cytochrome c-mediated apoptosis via the mitochondrial pathway. These results demonstrated the cytotoxic and apoptotic ability of 7α-hydroxy-β-sitosterol and suggest its potential anti-cancer use particularly on breast adenocarcinoma cells.

  5. Fractalkine expression induces endothelial progenitor cell lysis by natural killer cells.

    Directory of Open Access Journals (Sweden)

    Dilyana Todorova

    Full Text Available BACKGROUND: Circulating CD34(+ cells, a population that includes endothelial progenitors, participate in the maintenance of endothelial integrity. Better understanding of the mechanisms that regulate their survival is crucial to improve their regenerative activity in cardiovascular and renal diseases. Chemokine-receptor cross talk is critical in regulating cell homeostasis. We hypothesized that cell surface expression of the chemokine fractalkine (FKN could target progenitor cell injury by Natural Killer (NK cells, thereby limiting their availability for vascular repair. METHODOLOGY/PRINCIPAL FINDINGS: We show that CD34(+-derived Endothelial Colony Forming Cells (ECFC can express FKN in response to TNF-α and IFN-γ inflammatory cytokines and that FKN expression by ECFC stimulates NK cell adhesion, NK cell-mediated ECFC lysis and microparticles release in vitro. The specific involvement of membrane FKN in these processes was demonstrated using FKN-transfected ECFC and anti-FKN blocking antibody. FKN expression was also evidenced on circulating CD34(+ progenitor cells and was detected at higher frequency in kidney transplant recipients, when compared to healthy controls. The proportion of CD34(+ cells expressing FKN was identified as an independent variable inversely correlated to CD34(+ progenitor cell count. We further showed that treatment of CD34(+ circulating cells isolated from adult blood donors with transplant serum or TNF-α/IFN-γ can induce FKN expression. CONCLUSIONS: Our data highlights a novel mechanism by which FKN expression on CD34(+ progenitor cells may target their NK cell mediated killing and participate to their immune depletion in transplant recipients. Considering the numerous diseased contexts shown to promote FKN expression, our data identify FKN as a hallmark of altered progenitor cell homeostasis with potential implications in better evaluation of vascular repair in patients.

  6. Delayed Diagnosis of Nasal Natural Killer/T-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Jennifer A. Villwock

    2013-01-01

    Full Text Available Midline destructive lesions of the face have multiple possible etiologies. The majority of these cases are found to be due to an extranodal lymphoma of natural killer/T-cell-type non-Hodgkins lymphoma (NKTL. Unfortunately, diagnosis is often delayed. With variable presenting complaints, including nonspecific issues like chronic rhinosinusitis or nasal congestion, initial treatments are aimed at these presumed diagnoses. Only as the lesion progresses do overt signs of destruction occur. As with our patient, who was initially treated for presumed infection and abscess, final diagnosis often does not occur until several months, and several antibiotic courses, from initial presentation. As such, it is important for this rare entity to remain in the clinician’s differential diagnosis for nasal lesion.

  7. Novel targets for natural killer/T-cell lymphoma immunotherapy.

    Science.gov (United States)

    Kumai, Takumi; Kobayashi, Hiroya; Harabuchi, Yasuaki

    2016-01-01

    Extranodal natural killer/T-cell lymphoma, nasal type (NKTL) is a rare but highly aggressive Epstein-Barr virus-related malignancy, which mainly occurs in nasopharyngeal and nasal/paranasal areas. In addition to its high prevalence in Asian, Central American and South American populations, its incidence rate has been gradually increasing in Western countries. The current mainstay of treatment is a combination of multiple chemotherapies and irradiation. Although chemoradiotherapy can cure NKTL, it often causes severe and fatal adverse events. Because a growing body of evidence suggests that immunotherapy is effective against hematological malignancies, this treatment could provide an alternative to chemoradiotherapy for treatment of NKTL. In this review, we focus on how recent findings could be used to develop efficient immunotherapies against NKTL.

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

    NARCIS (Netherlands)

    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.; Boes, Marianne; Nierkens, Stefan

    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

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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

  11. Nasosinusal Lymphoma of T Natural Killer Cells: Case Report

    Directory of Open Access Journals (Sweden)

    Castro, Victor Labres da Silva

    2011-01-01

    Full Text Available Introduction: The primary nasal lymphoma is an uncommon extranodal tumor and represents 0.44% of all Extranodal lymphomas in this region. The primary nasal lymphoma derives from the T-lineage in nearly 75% of the cases. Objective: To describe a case of nasosinusal lymphoma of T Natural Killer cells, attended in the Clinical Hospital of the Federal University of Goiás. Case Report: 48-year-old female patient with diffuse tumefaction in the left hemiface of firm-elastic consistency and painful upon digital compression. Face sinuses tomography identified a total maxillary veiling to the left and some posterior ethmoidal cells. With the diagnostic hypothesis of a tumor affection, we opted for the surgical removal via a transmaxillary approach and the material was sent for biopsy. The histopathological exam diagnosed a highly necrotic tumor of angiocentric pattern, polymorphic and atypical lymphoid population (T /NK Lymphoma; with the prognosis, the patient was submitted to chemical therapy with total regression of the facial edema. Final Comments: The otorhinolaryngologist must be attentive as regards the existence of lymphomas among the nasosinusal diseases, because the early diagnosis improves the survival as it prevents metastases, growth and local destruction.

  12. Are natural killer cells protecting the metabolically healthy obese patient?

    LENUS (Irish Health Repository)

    Lynch, Lydia A

    2012-02-01

    With the emerging obesity pandemic, identifying those who appear to be protected from adverse consequences such as type 2 diabetes and certain malignancies will become important. We propose that the circulating immune system plays a role in the development of these comorbidities. Clinical data and blood samples were collected from 52 patients with severe obesity attending a hospital weight-management clinic and 11 lean healthy controls. Patients were classified into metabolically "healthy obese" (n = 26; mean age 42.6 years, mean BMI 46.8 kg\\/m(2)) or "unhealthy obese" (n = 26; mean age 45 years, mean BMI 47.5 kg\\/m(2)) groups, based upon standard cutoff points for blood pressure, lipid profile, and fasting glucose. Circulating lymphoid populations and phenotypes were assessed by flow cytometry. Obese patients had significantly less circulating natural killer (NK) and cytotoxic T lymphocytes (CTL) compared to lean controls. There were significantly higher levels of NK cells and CTLs in the healthy obese group compared to the unhealthy obese group (NK: 11.7% vs. 6.5%, P < 0.0001, CD8 13.4% vs. 9.3%, P = 0.04), independent of age and BMI and these NK cells were also less activated in the healthy compared to the unhealthy group (CD69, 4.1% vs. 11.8%, P = 0.03). This is the first time that quantitative differences in the circulating immune system of obese patients with similar BMI but different metabolic profiles have been described. The significantly higher levels of CTLs and NK cells, which express fewer inhibitory molecules, could protect against malignancy, infection, and metabolic disease seen in obesity.

  13. The nature and dynamics of spermatogonial stem cells

    NARCIS (Netherlands)

    de Rooij, Dirk G.

    2017-01-01

    Spermatogonial stem cells (SSCs) are crucial for maintaining spermatogenesis throughout life, and understanding how these cells function has important implications for understanding male infertility. Recently, various populations of cells harbouring stem cell-like properties have been identified in

  14. Innate lymphoid cells and natural killer T cells in the gastrointestinal tract immune system

    Directory of Open Access Journals (Sweden)

    Enrique Montalvillo

    2014-05-01

    Full Text Available The gastrointestinal tract is equipped with a highly specialized intrinsic immune system. However, the intestine is exposed to a high antigenic burden that requires a fast, nonspecific response -so-called innate immunity- to maintain homeostasis and protect the body from incoming pathogens. In the last decade multiple studies helped to unravel the particular developmental requirements and specific functions of the cells that play a role in innate immunity. In this review we shall focus on innate lymphoid cells, a newly discovered, heterogeneous set of cells that derive from an Id2-dependent lymphoid progenitor cell population. These cells have been categorized on the basis of the pattern of cytokines that they secrete, and the transcription factors that regulate their development and functions. Innate lymphoid cells play a role in the early response to pathogens, the anatomical contention of the commensal flora, and the maintenance of epithelial integrity. Amongst the various innate lymphoid cells we shall lay emphasis on a subpopulation with several peculiarities, namely that of natural killer T cells, a subset of T lymphocytes that express both T-cell and NK-cell receptors. The most numerous fraction of the NKT population are the so-called invariant NKT or iNKT cells. These iNKT cells have an invariant TCR and recognize the glycolipidic structures presented by the CD1d molecule, a homolog of class-I MHC molecules. Following activation they rapidly acquire cytotoxic activity and secrete both Th1 and Th2 cytokines, including IL-17. While their specific role is not yet established, iNKT cells take part in a great variety of intestinal immune responses ranging from oral tolerance to involvement in a number of gastrointestinal conditions.

  15. Phosphatidylinositol turnover is associated with human natural killer cell activation by tumor target cells

    International Nuclear Information System (INIS)

    Steele, T.A.; Brahmi, Z.

    1986-01-01

    Natural Killer (NK) cell activity has been shown to be a binding-dependent event leading to the destruction of various targets. This suggests a possible role for plasma membrane phospholipid turnover in coupling a receptor-mediated binding event with transduction of a intracellular signal to result in the activation of the effector cell. Currently, phosphatidylinositol (PI) turnover is implicated in several immune cell systems. Therefore, in this study, the authors examined phospholipid turnover in human NK cells upon exposure to a sensitive (K562) and a resistant (YAC-1) target cell (TC). NK cell membrane phospholipids were labelled with Phosphorus-32 ( 32 P) and, following stimulation, were extracted and run on silica gel thin-layer chromatography. Labelled phospholipids were visualized by autoradiography then scraped and counted in a liquid scintillation counter. A 2.5 fold increase in label incorporation into PI relative to controls was shown to occur when NK cells were stimulated by K562 for 2 hours. In contrast, no increased labelling of PI relative to controls was noted when NK cells were stimulated by YAC-1 for the same period of time. No change in incorporation of 32 P into phosphatidylcholine or phosphatidylethanolamine occurred in either set of conditions. These results suggest that PI turnover may be an early activation event in NK cells following binding of K562

  16. Hypoglycemic and anti apoptotic effect of garlic in streptozotocin ...

    African Journals Online (AJOL)

    Egyptian Journal of Biochemistry and Molecular Biology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 29, No 2 (2011) >. Log in or Register to get access to full text downloads.

  17. Flavokawain C Inhibits Cell Cycle and Promotes Apoptosis, Associated with Endoplasmic Reticulum Stress and Regulation of MAPKs and Akt Signaling Pathways in HCT 116 Human Colon Carcinoma Cells.

    Directory of Open Access Journals (Sweden)

    Chung-Weng Phang

    Full Text Available Flavokawain C (FKC is a naturally occurring chalcone which can be found in Kava (Piper methysticum Forst root. The present study evaluated the effect of FKC on the growth of various human cancer cell lines and the underlying associated mechanisms. FKC showed higher cytotoxic activity against HCT 116 cells in a time- and dose-dependent manner in comparison to other cell lines (MCF-7, HT-29, A549 and CaSki, with minimal toxicity on normal human colon cells. The apoptosis-inducing capability of FKC on HCT 116 cells was evidenced by cell shrinkage, chromatin condensation, DNA fragmentation and increased phosphatidylserine externalization. FKC was found to disrupt mitochondrial membrane potential, resulting in the release of Smac/DIABLO, AIF and cytochrome c into the cytoplasm. Our results also revealed that FKC induced intrinsic and extrinsic apoptosis via upregulation of the levels of pro-apoptotic proteins (Bak and death receptors (DR5, while downregulation of the levels of anti-apoptotic proteins (XIAP, cIAP-1, c-FlipL, Bcl-xL and survivin, resulting in the activation of caspase-3, -8 and -9 and cleavage of poly(ADP-ribose polymerase (PARP. FKC was also found to cause endoplasmic reticulum (ER stress, as suggested by the elevation of GADD153 protein after FKC treatment. After the cells were exposed to FKC (60μM over 18hrs, there was a substantial increase in the phosphorylation of ERK 1/2. The expression of phosphorylated Akt was also reduced. FKC also caused cell cycle arrest in the S phase in HCT 116 cells in a time- and dose-dependent manner and with accumulation of cells in the sub-G1 phase. This was accompanied by the downregulation of cyclin-dependent kinases (CDK2 and CDK4, consistent with the upregulation of CDK inhibitors (p21Cip1 and p27Kip1, and hypophosphorylation of Rb.

  18. The immunoregulatory role of CD1d-restricted natural killer T cells in disease.

    NARCIS (Netherlands)

    Vliet, van der HJ; Molling, J.W.; Blomberg - van der Flier, von B.M.E.; Nishi, N.; Kolgen, W; Eertwegh, van den A.J.M.; Pinedo, H.M.; Giaccone, G.; Scheper, R.J.

    2004-01-01

    Natural killer T (NKT) cells constitute a T cell subpopulation that shares several characteristics with NK cells. NKT cells are characterized by a narrow T cell antigen receptor (TCR) repertoire, recognize glycolipid antigen in the context of the monomorphic CD1d antigen-presenting molecule, and

  19. Antigen Presenting Cells and Stromal Cells Trigger Human Natural Killer Lymphocytes to Autoreactivity: Evidence for the Involvement of Natural Cytotoxicity Receptors (NCR and NKG2D

    Directory of Open Access Journals (Sweden)

    Alessandro Poggi

    2006-01-01

    Full Text Available Human natural killer (NK lymphocytes should not damage autologous cells due to the engagement of inhibitory receptor superfamily (IRS members by HLA-I. Nevertheless, NK cells kill self cells expressing low levels or lacking HLA-I, as it may occur during viral infections (missing-self hypothesis. Herein, we show that human NK cells can be activated upon binding with self antigen presenting cells or stromal cells despite the expression of HLA-I. Indeed, NK cells can kill and produce pro-inflammatory and regulating cytokines as IFN-γ, TNF-α and IL10 during interaction with autologous dendritic cells or bone marrow stromal cells or skin fibroblasts. The killing of antigen presenting and stromal cells is dependent on LFA1/ICAM1 interaction. Further, the natural cytotoxicity receptors (NCR NKp30 and NKp46 are responsible for the delivery of lethal hit to DC, whereas NKG2D activating receptor, the ligand of the MHC-related molecule MIC-A and the UL16 binding protein, is involved in stromal cell killing. These findings indicate that different activating receptors are involved in cell to self cell interaction. Finally, NK cells can revert the veto effect of stromal cells on mixed lymphocyte reaction further supporting the idea that NK cells may alter the interaction between T lymphocytes and microenvironment leading to autoreactivity.

  20. Melatonin promotes Bax sequestration to mitochondria reducing cell susceptibility to apoptosis via the lipoxygenase metabolite 5-hydroxyeicosatetraenoic acid.

    Science.gov (United States)

    Radogna, F; Albertini, M C; De Nicola, M; Diederich, M; Bejarano, I; Ghibelli, L

    2015-03-01

    Extra-neurological functions of melatonin include control of the immune system and modulation of apoptosis. We previously showed that melatonin inhibits the intrinsic apoptotic pathway in leukocytes via stimulation of high affinity MT1/MT2 receptors, thereby promoting re-localization of the anti-apoptotic Bcl-2 protein to mitochondria. Here we show that Bcl-2 sequesters pro-apoptotic Bax into mitochondria in an inactive form after melatonin treatment, thus reducing cell propensity to apoptosis. Bax translocation and the anti-apoptotic effect of melatonin are strictly dependent on the presence of Bcl-2, and on the 5-lipoxygenase (5-LOX) metabolite 5-hydroxyeicosatetraenoic acid (5-HETE), which we have previously shown to be produced as a consequence of melatonin binding to its low affinity target calmodulin. Therefore, the anti-apoptotic effect of melatonin requires the simultaneous, independent interaction with high (MT1/MT2) and low (calmodulin) affinity targets, eliciting two independent signal transduction pathways converging into Bax sequestration and inactivation. MT1/MT2 vs. lipoxygenase pathways are activated by 10(-9) vs. 10(-5)M melatonin, respectively; the anti-apoptotic effect of melatonin is achieved at 10(-5)M, but drops to 10(-9)M upon addition of exogenous 5-HETE, revealing that lipoxygenase activation is the rate-limiting pathway. Therefore, in areas of inflammation with increased 5-HETE levels, physiological nanomolar concentrations of melatonin may suffice to maintain leukocyte viability. Copyright © 2015 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  1. Natural killer (NK)-cell activity in sorted subsets of peripheral blood mononuclear cells from patients with severe combined immunodeficiency

    NARCIS (Netherlands)

    ten Berge, R. J.; Schellekens, P. T.; Budding-Koppenol, A.; Dooren, L. J.; Vossen, J. M.

    1987-01-01

    Natural killer-cell activity for K562 target cells was measured in 13 patients with severe combined immunodeficiency before bone marrow transplantation. Both unseparated peripheral blood mononuclear cells and sorted cell subsets (B73.1 positive, B73.1 negative, OKT3 positive, OKT3 negative) were

  2. Cathepsin D inhibits oxidative stress-induced cell death via activation of autophagy in cancer cells.

    Science.gov (United States)

    Hah, Young-Sool; Noh, Hae Sook; Ha, Ji Hye; Ahn, Jin Sook; Hahm, Jong Ryeal; Cho, Hee Young; Kim, Deok Ryong

    2012-10-28

    Cathepsin D (CatD), a lysosomal aspartic protease, plays an essential role in tumor progression and apoptosis. However, the function of CatD in cell death is not yet fully understood. In this study, we identified CatD as one of up-regulated proteins in human malignant glioblastoma M059J cells that lack the catalytic subunit of DNA-PK compared with its isogenic M059K cells with normal DNA-PK activity. M059J cells were relatively more resistant to genotoxic stress than M059K cells. Overexpression of wild-type CatD but not catalytically inactive mutant CatD (D295N) inhibited H(2)O(2)-induced cell death in HeLa cells. Furthermore, knockdown of CatD expression abolished anti-apoptotic effect by CatD in the presence of H(2)O(2). Interestingly, high expression of CatD in HeLa cells significantly activated autophagy: increase of acidic autophagic vacuoles, LC3-II formation, and GFP-LC3 puncta. These results suggest that CatD can function as an anti-apoptotic mediator by inducing autophagy under cellular stress. In conclusion, inhibition of autophagy could be a novel strategy for the adjuvant chemotherapy of CatD-expressing cancers. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. A natural stem cell therapy? How novel findings and biotechnology clarify the ethics of stem cell research.

    Science.gov (United States)

    Patel, P

    2006-04-01

    The natural replacement of damaged cells by stem cells occurs actively and often in adult tissues, especially rapidly dividing cells such as blood cells. An exciting case in Boston, however, posits a kind of natural stem cell therapy provided to a mother by her fetus-long after the fetus is born. Because there is a profound lack of medical intervention, this therapy seems natural enough and is unlikely to be morally suspect. Nevertheless, we feel morally uncertain when we consider giving this type of therapy to patients who would not naturally receive it. Much has been written about the ethics of stem cell research and therapy; this paper will focus on how recent advances in biotechnology and biological understandings of development narrow the debate. Here, the author briefly reviews current stem cell research practices, revisits the natural stem cell therapy case for moral evaluation, and ultimately demonstrates the importance of permissible stem cell research and therapy, even absent an agreement about the definition of when embryonic life begins. Although one promising technology, blighted ovum utilisation, uses fertilised but developmentally bankrupt eggs, it is argued that utilisation of unfertilised eggs to derive totipotent stem cells obviates the moral debate over when life begins. There are two existing technologies that fulfil this criterion: somatic cell nuclear transfer and parthenogenic stem cell derivation. Although these technologies are far from therapeutic, concerns over the morality of embryonic stem cell derivation should not hinder their advancement.

  4. Lactic Acid Bacteria Differentially Activate Natural Killer Cells

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    antigen presenting cells and T-cells. Bacteria translocating across the gastrointestinal mucosa are presumed to gain access to NK cell compartments, as consumption of certain strains of lactic acid bacteria has been shown to increase in vivo NK cytotoxic activity. On-going research in our lab aims...... at describing strain-dependent effects of lactic acid bacteria on regulatory functions of NK-cells. Here, we have investigated how human gut flora-derived non-pathogenic lactic acid bacteria affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human peripheral blood NK cells upon...... bacterial stimulation. Methods: CD3-CD56+ NK cells were isolated from buffy coats by negative isolation using a lineage specific antibody cocktail and magnetic beads binding the labelling antibodies on non-NK cells. NK cells were incubated either with 10 microg/ml UV-inactivated lactic acid bacteria or 10...

  5. Human immunodeficiency syndromes affecting human natural killer cell cytolytic activity

    Directory of Open Access Journals (Sweden)

    Daniel Denis Billadeau

    2014-01-01

    Full Text Available NK cells are lymphocytes of the innate immune system that secrete cytokines upon activation and mediate the killing of tumor cells and virus-infected cells, especially those that escape the adaptive T-cell response caused by the down regulation of MHC-I. The induction of cytotoxicity requires that NK cells contact target cells through adhesion receptors, and initiate activation signaling leading to increased adhesion and accumulation of F-actin at the NK cell cytotoxic synapse. Concurrently, lytic granules undergo minus-end directed movement and accumulate at the microtubule-organizing center (MTOC through the interaction with microtubule motor proteins, followed by polarization of the lethal cargo toward the target cell. Ultimately, myosin-dependent movement of the lytic granules toward the NK cell plasma membrane through F-actin channels, along with SNARE-dependent fusion promotes lytic granule release into the cleft between the NK cell and target cell resulting in target cell killing. Herein, we will discuss several disease-causing mutations in primary immunodeficiency syndromes and how they impact NK cell-mediated killing by disrupting distinct steps of this tightly regulated process.

  6. Immunologic targeting of FOXP3 in inflammatory breast cancer cells.

    Directory of Open Access Journals (Sweden)

    Smita Nair

    Full Text Available The forkhead transcription factor FOXP3 is necessary for induction of regulatory T lymphocytes (Tregs and their immunosuppressive function. We have previously demonstrated that targeting Tregs by vaccination of mice with murine FOXP3 mRNA-transfected dendritic cells (DCs elicits FOXP3-specific T cell responses and enhances tumor immunity. It is clear that FOXP3 expression is not restricted to T-cell lineage and herein, using RT-PCR, flow cytometry, and western immunoblot we demonstrate for the first time that FOXP3 is expressed in inflammatory breast cancer (IBC cells, SUM149 (triple negative, ErbB1-activated and SUM190 (ErbB2-overexpressing. Importantly, FOXP3-specific T cells generated in vitro using human FOXP3 RNA-transfected DCs as stimulators efficiently lyse SUM149 cells. Interestingly, an isogenic model (rSUM149 derived from SUM149 with an enhanced anti-apoptotic phenotype was resistant to FOXP3-specific T cell mediated lysis. The MHC class I cellular processing mechanism was intact in both cell lines at the protein and transcription levels suggesting that the resistance to cytolysis by rSUM149 cells was not related to MHC class I expression or to the MHC class I antigen processing machinery in these cells. Our data suggest that FOXP3 may be an effective tumor target in IBC cells however increased anti-apoptotic signaling can lead to immune evasion.

  7. Early stages in the development of human T, natural killer and thymic dendritic cells

    NARCIS (Netherlands)

    Spits, H.; Blom, B.; Jaleco, A. C.; Weijer, K.; Verschuren, M. C.; van Dongen, J. J.; Heemskerk, M. H.; Res, P. C.

    1998-01-01

    T-cell development is initiated when CD34+ pluripotent stem cells or their immediate progeny leave the bone marrow to migrate to the thymus. Upon arrival in the thymus the stem cell progeny is not yet committed to the T-cell lineage as it has the capability to develop into T, natural killer (NK) and

  8. Characterization of the recognition of tumor cells by the natural cytotoxicity receptor, NKp44.

    NARCIS (Netherlands)

    Hershkovitz, O.; Jivov, S.; Bloushtain, N.; Zilka, A.; Landau, G.; Bar-Ilan, A.; Lichtenstein, R.G.; Campbell, K.S.; Kuppevelt, A.H.M.S.M. van; Porgador, A.

    2007-01-01

    NKp44 is a natural cytotoxicity receptor expressed by human NK cells upon activation. In this study, we demonstrate that cell surface heparan sulfate proteoglycans (HSPGs), expressed by target cells, are involved in the recognition of tumor cells by NKp44. NKp44 showed heparan sulfate-dependent

  9. Lymphomatoid papulosis with a natural killer-cell phenotype

    NARCIS (Netherlands)

    Bekkenk, M. W.; Kluin, P. M.; Jansen, P. M.; Meijer, C. J.; Willemze, R.

    2001-01-01

    Lymphomatoid papulosis (LyP) is defined as a recurrent self-healing papulonodular eruption with the histological features of a (CD30+) cutaneous T-cell lymphoma. The atypical cells usually have a CD3+/-, CD4+/-, CD8-, CD30+, CD56- T-cell phenotype. We report an unusual case of LyP, in which the

  10. Lymphomatoid papulosis with a natural killer-cell phenotype

    NARCIS (Netherlands)

    Bekkenk, MW; Kluin, PM; Jansen, PM; Meijer, CJLM; Willemze, R

    Lymphomatoid papulosis (LyP) is defined as a recurrent self-healing papulonodular eruption with the histological features of a (CD30+) cutaneous T-cell lymphoma. The atypical cells usually have a CD3+/-, CD4+/-, CD8-, CD30+, CD56- T-cell phenotype. We report an unusual case of LyP, in which the

  11. Lactobacilli Modulate Natural Killer Cell Responses In Vitro

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    of certain lactic acid bacteria has been shown to increase in vivo NK cytotoxicity. Here, we investigated how human gut flora-derived lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human NK cells upon bacterial stimulation. CD3-CD56+ NK cells were isolated from...... monocytes present, probably because cytokines, secreted by monocytes having engulfed bacteria, stimulated the NK cells. In contrast, a Lactobacillus paracasei strain caused the NK cells to proliferate only in the presence of monocytes. These results demonstrate that various strains of lactobacilli have...

  12. Natural Killer Cells and Their Activation Status in Normal Pregnancy

    Directory of Open Access Journals (Sweden)

    Beatrice Mosimann

    2013-01-01

    Full Text Available Increased peripheral blood-activated NK cell counts are associated with increased risk of miscarriage and failed in vitro fertilization treatment. However, assessment of activated peripheral NK cells in normal and pathological pregnancies beyond implantation and early miscarriage has not been described. Total CD69 expressing NK cells counts were measured by flow cytometry in healthy women with singleton pregnancies, including 45 at 11+6–13+6 weeks’ gestation, 46 at 20+0–22+4 weeks, and 42 at 31+6–33+5 weeks. The number of peripheral blood NK cells decreased, whereas the percentage of activated CD69 expressing NK cells increased from the first to the third trimester of pregnancy. This study shows the course of peripheral blood NK cells and activated CD69 expressing NK cells in uncomplicated nulliparous singleton pregnancies. This is a first step in understanding their implication in pathological pregnancies.

  13. PDGF-BB inhibits intervertebral disc cell apoptosis in vitro.

    Science.gov (United States)

    Presciutti, Steven M; Paglia, David N; Karukonda, Teja; Soung, Do Yu; Guzzo, Rosa; Drissi, Hicham; Moss, Isaac L

    2014-09-01

    Degeneration of the intervertebral disc (IVD) results in deterioration of the spinal motion segment and can lead to debilitating back pain. Given the established mitotic and anti-apoptotic effects of recombinant human platelet-derived growth factor-BB (rhPDGF-BB) in a variety of cell types we postulated that rhPDGF-BB might delay disc cell degeneration through inhibition of apoptosis. To address this hypothesis, we treated human IVD cells isolated from five independent patients with rhPDGF-BB in monolayer and 3D pellet cultures. The anti-apoptotic potential, cell proliferative capacity, morphology/pellet differentiation, and gene expression of PDGF-treated IVD cells were evaluated via flow cytometry/immunohistochemistry, MTT assays, histology, and quantitative RT-PCR, respectively. We found that rhPDGF-BB treatment significantly inhibited cell apoptosis, increased cell proliferation and matrix production, and maintained mRNA expression of critical extracellular matrix genes. This study suggests two possible mechanisms for the anti-degenerative effects of rhPDGF-BB on human IVD cells. First, PDGF treatment strongly inhibited IVD cell apoptosis in 3D cultures. Second, rhPDGF-BB acts as an anabolic agent, promoting maintenance of IVD cell phenotype in 3D culture, based on the molecular and protein expression analysis. We speculate that rhPDGF-BB may be used as a biologic treatment to target early degenerative IVD disease in the future. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  14. Role of NKG2D, DNAM-1 and natural cytotoxicity receptors in cytotoxicity toward rhabdomyosarcoma cell lines mediated by resting and IL-15-activated human natural killer cells.

    Science.gov (United States)

    Boerman, Gerharda H; van Ostaijen-ten Dam, Monique M; Kraal, Kathelijne C J M; Santos, Susy J; Ball, Lynne M; Lankester, Arjan C; Schilham, Marco W; Egeler, R Maarten; van Tol, Maarten J D

    2015-05-01

    Children with advanced stages (relapsed/refractory and stage IV) of rhabdomyosarcoma (RMS) have a poor prognosis despite intensive chemotherapy and autologous stem cell rescue, with 5-year survival rates ranging from 5 to 35 %. Development of new, additional treatment modalities is necessary to improve the survival rate. In this preclinical study, we investigated the potential of resting and cytokine-activated natural killer (NK) cells to lyse RMS cell lines, as well as the pathways involved, to explore the eventual clinical application of (activated) NK cell immunotherapy. RMS cell lines (n = 3 derived from embryonal RMS and n = 2 derived from alveolar RMS) were susceptible to cytolysis mediated by resting NK cells, and this susceptibility was significantly increased using IL-15-activated NK cells. Flow cytometry and cytolytic assays were used to define the activating and inhibitory pathways of NK cells involved in recognizing and lysing RMS cells. NKG2D and DNAM-1 receptor-ligand interactions were essential in cytolysis by resting NK cells, as simultaneous blocking of both pathways resulted in almost complete abrogation of the cytotoxicity. In contrast, combined blocking of DNAM-1 and NKG2D only led to partial reduction of the lytic activity of IL-15-activated NK cells. In this respect, residual lysis was, at least partly, mediated by pathways involving the natural cytotoxicity receptors NKp30 and NKp46. These findings support further exploration of NK cell-based immunotherapy as adjuvant modality in current treatment strategies of RMS.

  15. Poncirin Induces Apoptosis in AGS Human Gastric Cancer Cells through Extrinsic Apoptotic Pathway by up-Regulation of Fas Ligand

    Directory of Open Access Journals (Sweden)

    Venu Venkatarame Gowda Saralamma

    2015-09-01

    Full Text Available Poncirin, a natural bitter flavanone glycoside abundantly present in many species of citrus fruits, has various biological benefits such as anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer activities. The anti-cancer mechanism of Poncirin remains elusive to date. In this study, we investigated the anti-cancer effects of Poncirin in AGS human gastric cancer cells (gastric adenocarcinoma. The results revealed that Poncirin could inhibit the proliferation of AGS cells in a dose-dependent manner. It was observed Poncirin induced accumulation of sub-G1 DNA content, apoptotic cell population, apoptotic bodies, chromatin condensation, and DNA fragmentation in a dose-dependent manner in AGS cells. The expression of Fas Ligand (FasL protein was up-regulated dose dependently in Poncirin-treated AGS cells Moreover, Poncirin in AGS cells induced activation of Caspase-8 and -3, and subsequent cleavage of poly(ADP-ribose polymerase (PARP. Inhibitor studies’ results confirm that the induction of caspase-dependent apoptotic cell death in Poncirin-treated AGS cells was led by the Fas death receptor. Interestingly, Poncirin did not show any effect on mitochondrial membrane potential (ΔΨm, pro-apoptotic proteins (Bax and Bak and anti-apoptotic protein (Bcl-xL in AGS-treated cells followed by no activation in the mitochondrial apoptotic protein caspase-9. This result suggests that the mitochondrial-mediated pathway is not involved in Poncirin-induced cell death in gastric cancer. These findings suggest that Poncirin has a potential anti-cancer effect via extrinsic pathway-mediated apoptosis, possibly making it a strong therapeutic agent for human gastric cancer.

  16. Natural killer cells enhance the immune surveillance of cancer

    OpenAIRE

    Nouroz, Faisal; Bibi, Farzana; Noreen, Shumaila; Masood, Nosheen

    2016-01-01

    Immune system (IS) is comprised of molecules, cells, tissues and organs involved in host defense mechanism from infectious agents or tumor cells. On crossing the cell barriers by these infectious agents, the defense mechanism is alerted by the immune system to respond against these invading microbes. Innate immune response (IIR) and acquired immune response (AIR) are working in parallel to control these invading microbes. IIR is composed of various types of phagocytes and lymphocytes, while A...

  17. Modulation of natural killer cell activity by viruses.

    Science.gov (United States)

    Lisnić, Vanda Juranić; Krmpotić, Astrid; Jonjić, Stipan

    2010-08-01

    Since their discovery, our understanding of NK cells has evolved from branding them marginal innate immunity cells to key players in anti-viral and anti-tumor immunity. Importance of NK cells in control of various viral infections is perhaps best illustrated by the existence of plethora of viral mechanisms aimed to modulate their function. These mechanisms include not only virally encoded immunoevasion proteins but also viral miRNA. Moreover, the evidence has been accumulated supporting the role of viral immunoevasion of NK cells in viral pathogenesis in vivo. Copyright 2010 Elsevier Ltd. All rights reserved.

  18. [Natural nanotechnologies in living cell: view on the problem].

    Science.gov (United States)

    Chekman, I S

    2012-12-01

    Literature and research data concerning natural nanotechnology in living systems is summarized in this article. Over millions of years, nature has evolved complex processes controlling the functioning of living organisms. Using the principles of nature to create new tools and technologies is the current direction in the development of "smart" materials and systems. Physiologically active substances (amino acids, neurotransmitters, vitamins, albumin, ATP, fructose, DNA, RNA, fibrinogen, glutathione and others) are nano in size. Biological membranes, ion channels, nanopores, colloidal solutions of the body (blood, interstitial fluid) are nanostructures. The basic principle of nature reads: small tools make great work. In biological materials natural principle of high efficiency and minimum energy consumption is carried out due to the existence of natural nanotechnology that needs more study. In efficient energy-consuming processes during the evolution gradually disappeared and were replaced by more effective. The study and experimental proof of natural nanotechnology will bring a better understanding of the laws of physiological functioning of organs and those of metabolic processes that maintain life. The ability to reproduce biological form with nanoscale precision will find application in tissue engineering, drug delivery, modeling and development of sensory and immune systems, visualization and diagnostic tools. Natural nanotechnology is highly effective, low energy-consuming, causes a rapid flow of vital processes in the body, the ability to quickly response to external positive and negative factors. Not all data presented in this paper is experimentally confirmed, it may be controversial and require further extensive research by specialists of different areas to determine the role of nanotechnology and nanomechanisms in physiological, biochemical, immunological, genetic and other processes in living systems.

  19. Identification of Anti-tumor Cells Carrying Natural Killer (NK Cell Antigens in Patients With Hematological Cancers

    Directory of Open Access Journals (Sweden)

    Ewelina Krzywinska

    2015-10-01

    Full Text Available Natural killer (NK cells, a cytotoxic lymphocyte lineage, are able to kill tumor cells in vitro and in mouse models. However, whether these cells display an anti-tumor activity in cancer patients has not been demonstrated. Here we have addressed this issue in patients with several hematological cancers. We found a population of highly activated CD56dimCD16+ NK cells that have recently degranulated, evidence of killing activity, and it is absent in healthy donors. A high percentage of these cells expressed natural killer cell p46-related protein (NKp46, natural-killer group 2, member D (NKG2D and killer inhibitory receptors (KIRs and a low percentage expressed NKG2A and CD94. They are also characterized by a high metabolic activity and active proliferation. Notably, we found that activated NK cells from hematological cancer patients have non-NK tumor cell antigens on their surface, evidence of trogocytosis during tumor cell killing. Finally, we found that these activated NK cells are distinguished by their CD45RA+RO+ phenotype, as opposed to non-activated cells in patients or in healthy donors displaying a CD45RA+RO− phenotype similar to naïve T cells. In summary, we show that CD45RA+RO+ cells, which resemble a unique NK population, have recognized tumor cells and degranulate in patients with hematological neoplasias.

  20. The Role of Natural Killer T Cells in Cancer—A Phenotypical and Functional Approach

    Science.gov (United States)

    Krijgsman, Daniëlle; Hokland, Marianne; Kuppen, Peter J. K.

    2018-01-01

    Natural killer T (NKT) cells are a subset of CD1d-restricted T cells at the interface between the innate and adaptive immune system. NKT cells can be subdivided into functional subsets that respond rapidly to a wide variety of glycolipids and stress-related proteins using T- or natural killer (NK) cell-like effector mechanisms. Because of their major modulating effects on immune responses via secretion of cytokines, NKT cells are also considered important players in tumor immunosurveillance. During early tumor development, T helper (TH)1-like NKT cell subsets have the potential to rapidly stimulate tumor-specific T cells and effector NK cells that can eliminate tumor cells. In case of tumor progression, NKT cells may become overstimulated and anergic leading to deletion of a part of the NKT cell population in patients via activation-induced cell death. In addition, the remaining NKT cells become hyporesponsive, or switch to immunosuppressive TH2-/T regulatory-like NKT cell subsets, thereby facilitating tumor progression and immune escape. In this review, we discuss this important role of NKT cells in tumor development and we conclude that there should be three important focuses of future research in cancer patients in relation with NKT cells: (1) expansion of the NKT cell population, (2) prevention and breaking of NKT cell anergy, and (3) skewing of NKT cells toward TH1-like subsets with antitumor activity. PMID:29535734

  1. Downregulated TIPE2 is associated with poor prognosis and promotes cell proliferation in non-small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yuexia [Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Li, Xiaohui [Department of Cardiovascular Surgery, Henan Provincial People’s Hospital, Zhengzhou, Henan 450003 (China); Liu, Gang; Sun, Rongqing; Wang, Lirui [Intensive Care Unit, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Wang, Jing, E-mail: jing_wang1980@163.com [Department of Respiratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China); Wang, Hongmin, E-mail: hmwangzz@126.com [Department of Respiratory Medicine, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan 450052 (China)

    2015-01-30

    Highlights: • TIPE2 is down-regulated in NSCLC tissues. • TIPE2 inhibits NSCLC cell proliferation, colony formation and invasion. • TIPE2 reduces the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. - Abstract: The present study aims to investigate the expression pattern of TIPE2 protein and its clinical significance in human non-small cell lung cancer (NSCLC). We investigated the expression levels of TIPE2 in 96 NSCLC tumor samples by immunohistochemistry and then analyzed its clinical significance. Furthermore, the role of TIPE2 on the biological properties of the NSCLC cell line H1299 and A549 was experimentally tested in vitro and in vivo. We found that the expression level of TIPE2 was significantly higher in normal lung tissues compared with NSCLC tissues (P < 0.001), and TIPE2 downregulation was significantly correlated with advanced TNM stage (P = 0.006). TIPE2 expression was lower in lung cancer cell lines than normal bronchial cell line HBE. Transfection of TIPE2 plasmid was performed in H1299 and A549 cells. TIPE2 overexpression inhibited lung cancer cell proliferation, colony formation and cell invasive in vitro, and prevented lung tumor growth in vivo. In addition, TIPE2 transfection reduced the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. Taken together, our results demonstrate that TIPE2 might serve as a tumor suppressor in NSCLC progression.

  2. Downregulated TIPE2 is associated with poor prognosis and promotes cell proliferation in non-small cell lung cancer

    International Nuclear Information System (INIS)

    Li, Yuexia; Li, Xiaohui; Liu, Gang; Sun, Rongqing; Wang, Lirui; Wang, Jing; Wang, Hongmin

    2015-01-01

    Highlights: • TIPE2 is down-regulated in NSCLC tissues. • TIPE2 inhibits NSCLC cell proliferation, colony formation and invasion. • TIPE2 reduces the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. - Abstract: The present study aims to investigate the expression pattern of TIPE2 protein and its clinical significance in human non-small cell lung cancer (NSCLC). We investigated the expression levels of TIPE2 in 96 NSCLC tumor samples by immunohistochemistry and then analyzed its clinical significance. Furthermore, the role of TIPE2 on the biological properties of the NSCLC cell line H1299 and A549 was experimentally tested in vitro and in vivo. We found that the expression level of TIPE2 was significantly higher in normal lung tissues compared with NSCLC tissues (P < 0.001), and TIPE2 downregulation was significantly correlated with advanced TNM stage (P = 0.006). TIPE2 expression was lower in lung cancer cell lines than normal bronchial cell line HBE. Transfection of TIPE2 plasmid was performed in H1299 and A549 cells. TIPE2 overexpression inhibited lung cancer cell proliferation, colony formation and cell invasive in vitro, and prevented lung tumor growth in vivo. In addition, TIPE2 transfection reduced the anti-apoptotic Bcl-XL protein and mesenchymal marker N-cadherin expression. Taken together, our results demonstrate that TIPE2 might serve as a tumor suppressor in NSCLC progression

  3. Learning Complex Cell Invariance from Natural Videos: A Plausibility Proof

    National Research Council Canada - National Science Library

    Masquelier, Timothee; Serre, Thomas; Thorpe, Simon; Poggio, Tomaso

    2007-01-01

    .... Here we focus on the class of hierarchical feed-forward models of the ventral stream of the visual cortex, which extend the classical simple-to-complex cells model by Hubel and Wiesel to extra...

  4. Immunomodulatory Effect of Rhaphidophora korthalsii on Natural Killer Cell Cytotoxicity

    Directory of Open Access Journals (Sweden)

    Swee Keong Yeap

    2012-01-01

    Full Text Available The in vivo immunomodulatory effect of ethanolic extracts from leaves of Rhaphidophora korthalsii was determined via immune cell proliferation, T/NK cell phenotyping, and splenocyte cytotoxicity of BALB/c mice after 5 consecutive days of i.p. administration at various concentrations. Splenocyte proliferation index, cytotoxicity, peripheral blood T/NK cell population, and plasma cytokine (IL-2 and IFN-γ in mice were assessed on day 5 and day 15. High concentration of extract (350 μg/mice/day for 5 consecutive days was able to stimulate immune cell proliferation, peripheral blood NK cell population, IL-2, and IFN- γ cytokines, as well as splenocyte cytotoxicity against Yac-1 cell line. Unlike rIL-2 which degraded rapidly, the stimulatory effect from the extract managed to last until day 15. These results suggested the potential of this extract as an alternative immunostimulator, and they encourage further study on guided fractionation and purification to identify the active ingredients that contribute to this in vitro and in vivo immunomodulatory activity.

  5. A Combined Nutritional and Immunological Intervention to Activate Natural Cytotoxicity Against Breast Cancer Cells In Vitro and In Vivo

    Science.gov (United States)

    2008-07-01

    intervention to activate natural cytotoxicity against breast cancer cells in vitro and in vivo PRINCIPAL...NUMBER activate natural cytotoxicity against breast cancer cells in vitro and in vivo 5b. GRANT NUMBER W81XWH-07-1-0478 5c. PROGRAM ELEMENT...TERMS Breast cancer cells ; immunological activation; retinoic acid; natural killer T cells; 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF

  6. Bcl-2 silencing attenuates hypoxia-induced apoptosis resistance in pulmonary microvascular endothelial cells.

    Science.gov (United States)

    Cao, Yongmei; Jiang, Zhen; Zeng, Zhen; Liu, Yujing; Gu, Yuchun; Ji, Yingying; Zhao, Yupeng; Li, Yingchuan

    2016-01-01

    Pulmonary arterial hypertension (PAH) is a life-threatening disorder that ultimately causes heart failure. While the underlying causes of this condition are not well understood, previous studies suggest that the anti-apoptotic nature of pulmonary microvascular endothelial cells (PMVECs) in hypoxic environments contributes to PAH pathogenesis. In this study, we focus on the contribution of Bcl-2 and hypoxia response element (HRE) to apoptosis-resistant endothelial cells and investigate the mechanism. PMVECs obtained from either normal rats or apoptosis-resistant PMVECs obtained from PAH rats were transduced with recombinant lentiviral vectors carrying either Bcl-2-shRNA or HRE combined Bcl-2-shRNA, and then cultured these cells for 24 h under hypoxic (5% O2) or normoxic (21% O2) conditions. In normal PMVECs, Bcl-2-shRNA or HRE combined with Bcl-2-shRNA transduction successfully decreased Bcl-2 expression, while increasing apoptosis as well as caspase-3 and P53 expression in a normoxic environment. In a hypoxic environment, the effects of Bcl-2-shRNA treatment on cell apoptosis, and on Bcl-2, caspase-3, P53 expression were significantly suppressed. Conversely, HRE activation combined with Bcl-2-shRNA transduction markedly enhanced cell apoptosis and upregulated caspase-3 and P53 expression, while decreasing Bcl-2 expression. Furthermore, in apoptosis-resistant PMVECs, HRE-mediated Bcl-2 silencing effectively enhanced cell apoptosis and caspase-3 activity. The apoptosis rate was significantly depressed when Lv-HRE-Bcl-2-shRNA was combined with Lv-P53-shRNA or Lv-caspase3-shRNA transduction in a hypoxic environment. These results suggest that HRE-mediated Bcl-2 inhibition can effectively attenuate hypoxia-induced apoptosis resistance in PMVECs by downregulating Bcl-2 expression and upregulating caspase-3 and P53 expression. This study therefore reveals critical insight into potential therapeutic targets for treating PAH.

  7. Gene expression and pathway analysis of human hepatocellular carcinoma cells treated with cadmium.

    Science.gov (United States)

    Cartularo, Laura; Laulicht, Freda; Sun, Hong; Kluz, Thomas; Freedman, Jonathan H; Costa, Max

    2015-11-01

    Cadmium (Cd) is a toxic and carcinogenic metal naturally occurring in the Earth's crust. A common route of human exposure is via diet and cadmium accumulates in the liver. The effects of Cd exposure on gene expression in human hepatocellular carcinoma (HepG2) cells were examined in this study. HepG2 cells were acutely-treated with 0.1, 0.5, or 1.0 μM Cd for 24h; or chronically-treated with 0.01, 0.05, or 0.1 μM Cd for three weeks and gene expression analysis was performed using Affymetrix GeneChip® Human Gene 1.0 ST Arrays. Acute and chronic exposures significantly altered the expression of 333 and 181 genes, respectively. The genes most upregulated by acute exposure included several metallothioneins. Downregulated genes included the monooxygenase CYP3A7, involved in drug and lipid metabolism. In contrast, CYP3A7 was upregulated by chronic Cd exposure, as was DNAJB9, an anti-apoptotic J protein. Genes downregulated following chronic exposure included the transcriptional regulator early growth response protein 1. Ingenuity Pathway Analysis revealed that the top networks altered by acute exposure were lipid metabolism, small molecule biosynthesis, cell morphology, organization, and development; while top networks altered by chronic exposure were organ morphology, cell cycle, cell signaling, and renal and urological diseases/cancer. Many of the dysregulated genes play important roles in cellular growth, proliferation, and apoptosis, and may be involved in carcinogenesis. In addition to gene expression changes, HepG2 cells treated with cadmium for 24h indicated a reduction in global levels of histone methylation and acetylation that persisted 72 h post-treatment. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Apoptosis of pancreatic β-cells in Type 1 diabetes

    Directory of Open Access Journals (Sweden)

    Tatsuo Tomita

    2017-08-01

    Full Text Available Type 1 diabetes mellitus (T1DM results from autoimmune destruction of pancreatic β-cells after an asymptomatic period over years. Insulitis activates antigen presenting cells, which trigger activating CD4+ helper-T cells, releasing chemokines/cytokines. Cytokines activate CD8+ cytotoxic–T cells, which lead to β-cell destruction. Apoptosis pathway consists of extrinsic (receptor-mediated and intrinsic (mitochondria-driven pathway. Extrinsic pathway includes Fas pathway to CD4+-CD8+ interaction, whereas intrinsic pathway includes mitochondria-driven pathway at a balance between anti-apoptotic B-cell lymphoma (Bcl-2 and Bcl-xL and pro-apoptotic Bad, Bid, and Bik proteins. Activated cleaved caspse-3 is the converging point between extrinsic and intrinsic pathway. Apoptosis takes place only when pro-apoptotic proteins exceed anti-apoptotic proteins. Since the concordance rate of T1DM in identical twins is about 50%, environmental factors are involved in the development of T1DM, opening a door to find means to detect and prevent further development of autoimmune β-cell destruction for a therapeutic application.

  9. Bim and Mcl-1 exert key roles in regulating JAK2V617F cell survival

    International Nuclear Information System (INIS)

    Rubert, Joëlle; Qian, Zhiyan; Andraos, Rita; Guthy, Daniel A; Radimerski, Thomas

    2011-01-01

    The JAK2 V617F mutation plays a major role in the pathogenesis of myeloproliferative neoplasms and is found in the vast majority of patients suffering from polycythemia vera and in roughly every second patient suffering from essential thrombocythemia or from primary myelofibrosis. The V617F mutation is thought to provide hematopoietic stem cells and myeloid progenitors with a survival and proliferation advantage. It has previously been shown that activated JAK2 promotes cell survival by upregulating the anti-apoptotic STAT5 target gene Bcl-xL. In this study, we have investigated the role of additional apoptotic players, the pro-apoptotic protein Bim as well as the anti-apoptotic protein Mcl-1. Pharmacological inhibition of JAK2/STAT5 signaling in JAK2 V617F mutant SET-2 and MB-02 cells was used to study effects on signaling, cell proliferation and apoptosis by Western blot analysis, WST-1 proliferation assays and flow cytometry. Cells were transfected with siRNA oligos to deplete candidate pro- and anti-apoptotic proteins. Co-immunoprecipitation assays were performed to assess the impact of JAK2 inhibition on complexes of pro- and anti-apoptotic proteins. Treatment of JAK2 V617F mutant cell lines with a JAK2 inhibitor was found to trigger Bim activation. Furthermore, Bim depletion by RNAi suppressed JAK2 inhibitor-induced cell death. Bim activation following JAK2 inhibition led to enhanced sequestration of Mcl-1, besides Bcl-xL. Importantly, Mcl-1 depletion by RNAi was sufficient to compromise JAK2 V617F mutant cell viability and sensitized the cells to JAK2 inhibition. We conclude that Bim and Mcl-1 have key opposing roles in regulating JAK2 V617F cell survival and propose that inactivation of aberrant JAK2 signaling leads to changes in Bim complexes that trigger cell death. Thus, further preclinical evaluation of combinations of JAK2 inhibitors with Bcl-2 family antagonists that also tackle Mcl-1, besides Bcl-xL, is warranted to assess the therapeutic potential

  10. Sulfatide-Reactive Natural Killer T Cells Abrogate Ischemia-Reperfusion Injury

    OpenAIRE

    Yang, Seung Hee; Lee, Jung Pyo; Jang, Hye Ryoun; Cha, Ran-hui; Han, Seung Seok; Jeon, Un Sil; Kim, Dong Ki; Song, Junghan; Lee, Dong-Sup; Kim, Yon Su

    2011-01-01

    There is a significant immune response to ischemia-reperfusion injury (IRI), but the role of immunomodulatory natural killer T (NKT) cell subtypes is not well understood. Here, we compared the severity of IRI in mice deficient in type I/II NKT cells (CD1d−/−) or type I NKT cells (Jα18−/−). The absence of NKT cells, especially type II NKT cells, accentuated the severity of renal injury, whereas repletion of NKT cells attenuated injury. Adoptively transferred NKT cells trafficked into the tubul...

  11. [Experiment research of natural killer cells amplification in vitro and the killing effect on ovarian cancer cells].

    Science.gov (United States)

    Cheng, H Y; Ye, X; Ma, R Q; Chang, X H; Cui, H

    2017-08-25

    Objective: To amplify natural killer (NK) cells in vitro and explore its killing effect on ovarian cancer cells. Methods: (1) The separation of NK cells and identification. A total of 20 ml peripheral blood of one healthy volunteer was collected in Nov. 2015, Peking University People's Hospital. The peripheral blood mononuclear cells of normal volunteers were isolated, cultured in vitro and amplificated cultivation for 14 days with K562 cells transfected and expressing interleukin 21 (IL-21-K562) as nourish cells. The number and dynamic state of the growth cells were monitored during the cultured process. Cells were harvested and counted after 14 days cultured. The NK cells phenotypes were detected by flow cytometry. (2) The killing effect of NK cells on ovarian cancer cells: the ratio of effector cells (NK cells) and target cells (ovarian cancer cells and its control) was 50∶1, 20∶1, 10∶1, 5∶1 or 1∶1, NK cells killing effect on ovarian cancer cells was detected by the lactate dehydrogenase (LDH) release experiments. Results: (1) The results of NK cells establishment and phenotypic characterization: the cells were induced in vitro for 14 days by amplification culture. With the extension of incubation time, the number of NK cells increased constantly, from 2.0×10(7) on day 0 to 5.1×10(9) on day 14. Obvious amplification of the total number of cells were detected for 255 times. Living cells unstained by trypan blue eventually reached 95% above. Before and after the induction and amplification in vitro, the percentage of NK cells(CD(3)(-)CD(5)(6+)cells) in CD(3)- cells were 2.33% and 85.32%, respectively ( P cancer cells in vitro: the results detected by LDH release experiments showed that NK cells could performed strong nonspecific killing effect on ovarian cancer cell lines SKOV3, HOC1A, 3AO and CAOV3, as well the normal ovarian cell line T29 and NK sensitive cell line K562, and the killing effect increased significantly along with the increase of

  12. Live cell linear dichroism imaging reveals extensive membrane ruffling within the docking structure of natural killer cell immune synapses

    DEFF Research Database (Denmark)

    Benninger, Richard K P; Vanherberghen, Bruno; Young, Stephen

    2009-01-01

    We have applied fluorescence imaging of two-photon linear dichroism to measure the subresolution organization of the cell membrane during formation of the activating (cytolytic) natural killer (NK) cell immune synapse (IS). This approach revealed that the NK cell plasma membrane is convoluted...... into ruffles at the periphery, but not in the center of a mature cytolytic NK cell IS. Time-lapse imaging showed that the membrane ruffles formed at the initial point of contact between NK cells and target cells and then spread radialy across the intercellular contact as the size of the IS increased, becoming...

  13. Targeting cancer cells with the natural compound obtusaquinone.

    Science.gov (United States)

    Badr, Christian E; Van Hoppe, Stephanie; Dumbuya, Hawasatu; Tjon-Kon-Fat, Lee-Ann; Tannous, Bakhos A

    2013-05-01

    Tumor cells present high levels of oxidative stress. Cancer therapeutics exploiting such biochemical changes by increasing reactive oxygen species (ROS) production or decreasing intracellular ROS scavengers could provide a powerful treatment strategy. To test the effect of our compound, obtusaquinone (OBT), we used several cell viability assays on seven different glioblastoma (GBM) cell lines and primary cells and on 12 different cell lines representing various cancer types in culture as well as on subcutaneous (n = 7 mice per group) and two intracranial GBM (n = 6-8 mice per group) and breast cancer (n = 6 mice per group) tumor models in vivo. Immunoblotting, immunostaining, flow cytometry, and biochemical assays were used to investigate the OBT mechanism of action. Histopathological analysis (n = 2 mice per group) and blood chemistry (n = 2 mice per group) were used to test for any compound-related toxicity. Statistical tests were two-sided. OBT induced rapid increase in intracellular ROS levels, downregulation of cellular glutathione levels and increase in its oxidized form, and activation of cellular stress pathways and DNA damage, subsequently leading to apoptosis. Oxidative stress is believed to be the main mechanism through which this compounds targets cancer cells. OBT was well tolerated in mice, slowed tumor growth, and statistically prolonged survival in GBM tumor models. The ratio of median survival in U251 intracranial model in OBT vs control was 1.367 (95% confidence interval [CI] of ratio = 1.031 to 1.367, P = .008). Tumor growth inhibition was also observed in a mouse breast cancer model (average tumor volume per mouse, OBT vs control: 36.3 vs 200.4mm(3), difference = 164.1mm(3), 95% CI =72.6 to 255.6mm(3), P = .005). Given its properties and efficacy in cancer killing, our results suggest that OBT is a promising cancer therapeutic.

  14. [Decidual natural killer cells in recurrent spontaneous abortions].

    Science.gov (United States)

    Janosević, Dragana Radović; Lilić, Vekoslav; Basić, Hakija; Pavlović, Aleksandra Tubić; Stefanović, Milan; Milosević, Jelena

    2011-01-01

    A repeated or habitual miscarriage (PSP) is defined as three or more consecutive losses of pregnancy. In the first three months of pregnancy, habitual miscarriages occur in about 1% of pregnant women, out of which 50% are of an unknown etiology. It is believed that among them, the greatest number is the consequence of an inadequate alloimmune response of a women to the pregnancy. The endocrine and immune systems are in a close interaction during the implantation and maintaining of pregnancy. This communication is the most obvious on endometrium of pregnancy decidua. The aim of the study was to identify the number and the subpopulation distribution of the decidual NK cells in the decidua by using an immunohistochemical method. The research included a group of 30 women who had had two spontaneous miscarriages consecutively in the first three months of their pregnancy, while the curettage after the third spontaneous abortion was histopathologically and immunohistochemically analyzed. The control group consisted of 20 women without a problematic reproductive anamnesis, who had had their pregnancy terminated for social reasons. The criteria for the eliminating from the research were the diagnosed uterus anomalies, positive screening on thrombophilia, as well as women suffering from diabetes melitus and the ones with the thyroid gland function disorder. The number and the phenotype structure of the uterus NK cells were significantly different between the decidua of a normal pregnancy and that in PSP. In the decidua in PSP, there were much more NK cells with the phenotype of the peripheral circulation CD57 and CD56dim, while in the decidua of the control group the dominant cells were the typical uNK cell subpopulation CD56bright. The above mentioned results show that the disregulation of the immunocompetent cells of the decidua, by creating an inadequate cytokine milieu, is one of the mechanism of rejecting the semiallogeneic blastocyst.

  15. Decidual natural killer cells in recurrent spontaneous abortions

    Directory of Open Access Journals (Sweden)

    Radović-Janošević Dragana

    2011-01-01

    Full Text Available Background/Aim. A repeated or habitual miscarriage (PSP is defined as three or more consecutive losses of pregnancy. In the first three months of pregnancy, habitual miscarriages occur in about 1% of pregnant women, out of which 50% are of an unknown etiology. It is believed that among them, the greatest number is the consequence of an inadequate alloimmune response of a women to the pregnancy. The endocrine and immune systems are in a close interaction during the implantation and maintaining of pregnancy. This communication is the most obvious on endometrium of pregnancy decidua. The aim of the study was to identify the number and the subpopulation distribution of the decidual NK cells in the decidua by using an immunohistochemical method. Methods. The research included a group of 30 women who had had two spontaneous miscarriages consecutively in the first three months of their pregnancy, while the curettage after the third spontaneous abortion was histopathologically and immunohistochemically analyzed. The control group consisted of 20 women without a problematic reproductive anamnesis, who had had their pregnancy terminated for social reasons. The criteria for the eliminating from the research were the diagnosed uterus anomalies, positive screening on thrombophilia, as well as women suffering from diabetes melitus and the ones with the thyroid gland function disorder. Results. The number and the phenotype structure of the uterus NK cells were significantly different between the decidua of a normal pregnancy and that in PSP. In the decidua in PSP, there were much more NK cells with the phenotype of the peripheral circulation CD57 and CD56dim, while in the decidua of the control group the dominant cells were the typical uNK cell subpopulation CD56bright. Conclusion. The above mentioned results show that the disregulation of the immunocompetent cells of the decidua, by creating an inadequate cytokine milieu, is one of the mechanism of rejecting

  16. Liquid Fluoride Salt Experimentation Using a Small Natural Circulation Cell

    Energy Technology Data Exchange (ETDEWEB)

    Yoder Jr, Graydon L [ORNL; Heatherly, Dennis Wayne [ORNL; Williams, David F [ORNL; Elkassabgi, Yousri M. [Texas A& M University, Kingsville; Caja, Joseph [Electrochemical Systems, Inc.; Caja, Mario [ORNL; Jordan, John [Texas A& M University, Kingsville; Salinas, Roberto [Texas A& M University, Kingsville

    2014-04-01

    A small molten fluoride salt experiment has been constructed and tested to develop experimental techniques for application in liquid fluoride salt systems. There were five major objectives in developing this test apparatus: Allow visual observation of the salt during testing (how can lighting be introduced, how can pictures be taken, what can be seen) Determine if IR photography can be used to examine components submerged in the salt Determine if the experimental configuration provides salt velocity sufficient for collection of corrosion data for future experimentation Determine if a laser Doppler velocimeter can be used to quantify salt velocities. Acquire natural circulation heat transfer data in fluoride salt at temperatures up to 700oC All of these objectives were successfully achieved during testing with the exception of the fourth: acquiring velocity data using the laser Doppler velocimeter. This paper describes the experiment and experimental techniques used, and presents data taken during natural circulation testing.

  17. Advancement in bioprocess technology: parallels between microbial natural products and cell culture biologics.

    Science.gov (United States)

    Bandyopadhyay, Arpan A; Khetan, Anurag; Malmberg, Li-Hong; Zhou, Weichang; Hu, Wei-Shou

    2017-05-01

    The emergence of natural products and industrial microbiology nearly eight decades ago propelled an era of bioprocess innovation. Half a century later, recombinant protein technology spurred the tremendous growth of biologics and added mammalian cells to the forefront of industrial producing cells in terms of the value of products generated. This review highlights the process technology of natural products and protein biologics. Despite the separation in time, there is a remarkable similarity in their progression. As the new generation of therapeutics for gene and cell therapy emerges, its process technology development can take inspiration from that of natural products and biologics.

  18. A King Bolete, Boletus edulis (Agaricomycetes), RNA Fraction Stimulates Proliferation and Cytotoxicity of Natural Killer Cells Against Myelogenous Leukemia Cells.

    Science.gov (United States)

    Lemieszek, Marta Kinga; Nunes, Fernando Herminio Ferreira Milheiro; Sawa-Wejksza, Katarzyna; Rzeski, Wojciech

    2017-01-01

    Numerous studies indicate the crucial role of natural killer (NK) cells in the prevention of tumor growth and inhibition of their metastasis, which suggests the possibility of their use in cancer treatment. This therapeutic strategy required finding a selective NK cell stimulator that, upon administration, did not disturb organism homeostasis, unlike natural activators (interleukin-2 or interleukin-12). Because the majority of anticancer agents derived from Basidiomycetes are able to stimulate lymphocytes, we describe the influence of Boletus edulis RNA on a human NK cell line (NK92). Our studies showed that a B. edulis RNA fraction was not toxic against NK92 cells. Furthermore, the tested fraction significantly stimulated NK92 cell proliferation and their cytotoxicity against tumor cells. We demonstrate here, to our knowledge for the first time, that B. edulis RNA enhances NK cell activity and possesses immunomodulatory potential.

  19. Natural Killer cell recognition of melanoma: new clues for a more effective immunotherapy

    Directory of Open Access Journals (Sweden)

    Raquel eTarazona

    2016-01-01

    Full Text Available Natural killer cells participate in the early immune response against melanoma and also contribute to the development of an adequate adaptive immune response by their crosstalk with dendritic cells and cytokine secretion. Melanoma resistance to conventional therapies together with its high immunogenicity justifies the development of novel therapies aimed to stimulate effective immune responses against melanoma. However, melanoma cells frequently escape to CD8 T cell recognition by the down-regulation of major histocompatibility complex class I molecules. In this scenario, Natural killer cells emerge as potential candidates for melanoma immunotherapy due to their capacity to recognize and destroy melanoma cells expressing low levels of major histocompatibility complex class I molecules. In addition, the possibility to combine immune checkpoint blockade with other NK cell potentiating strategies (e.g. cytokine induction of activating receptors has opened new perspectives in the potential use of adoptive NK cell-based immunotherapy in melanoma.

  20. Anticoagulant drugs increase natural killer cell activity in lung cancer

    Czech Academy of Sciences Publication Activity Database

    Bobek, M.; Boubelík, Michael; Fišerová, Anna; Luptovcová, Martina; Vannucci, Luca; Kacprzak, G.; Kolodzej, J.; Majewski, A.M.; Hoffman, R. M.

    2005-01-01

    Roč. 47, č. 2 (2005), s. 215-223 ISSN 0169-5002 Institutional research plan: CEZ:AV0Z5052915 Keywords : anticoagulant drugs * lung cancer * NK cells Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.172, year: 2005

  1. Natural zwitterionic l-Carnitine as efficient cryoprotectant for solvent-free cell cryopreservation.

    Science.gov (United States)

    Zhai, Hongwen; Yang, Jing; Zhang, Jiamin; Pan, Chao; Cai, Nana; Zhu, Yingnan; Zhang, Lei

    2017-07-15

    Organic solvents, such as dimethyl sulfoxide (DMSO) and glycerol, have been commonly used as cryoprotectants (CPAs) in cell cryopreservation. However, their cytotoxicity and need of complex freezing protocols have impeded their applications especially in clinical cell therapy and regenerative medicine. Trehalose has been explored as a natural CPA to cryopreserve cells, but its poor cell permeability frequently results in low cryopreservation efficacy. In this work, we presented that a natural zwitterionic molecule-l-carnitine-could serve as a promising CPA for solvent-free cryopreservation. We demonstrated that l-carnitine possessed strong ability to depress water freezing point, and with ultrarapid freezing protocol, we studied the post-thaw survival efficiency of four cell lines (GLC-82 cells, MCF-7 cells, NIH-3T3 cells and Sheep Red Blood Cells) using l-carnitine without addition of any organic solvents. At the optimum l-carnitine concentration, all four cell lines could achieve above 80% survival efficiency, compared with the significantly lower efficiency using organic CPAs and trehalose. After cryopreservation, the recovered cell behaviors including cell attachment and proliferation were found to be similar to the normal cells, indicating that the cell functionalities were not affected. Moreover, l-carnitine showed no observable cytotoxicity, which was superior to the organic CPAs. This work offered an attractive alternative to traditional CPAs and held great promise to revolutionize current cryopreservation technologies, to benefit the patients in various cell-based clinical applications. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Current perspectives on natural killer cell education and tolerance: emerging roles for inhibitory receptors

    Directory of Open Access Journals (Sweden)

    Thomas LM

    2015-03-01

    Full Text Available L Michael Thomas Laboratory of Immunogenetics, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD, USA Abstract: Natural killer (NK cells are regulated through the coordinated functions of activating and inhibitory receptors. These receptors can act during the initial engagement of an NK cell with a target cell, or in subsequent NK cell engagements to maintain tolerance. Notably, each individual possesses a sizable minority-population of NK cells that are devoid of inhibitory receptors that recognize the surrounding MHC class I (ie, self-MHC. Since these NK cells cannot perform conventional inhibition, they are rendered less responsive through the process of NK cell education (also known as licensing in order to reduce the likelihood of auto-reactivity. This review will delineate current views on NK cell education, clarify various misconceptions about NK cell education, and, lastly, discuss the relevance of NK cell education in anti-cancer therapies. Keywords: natural killer cell education, natural killer cell inhibitory receptors, immunotherapy, cancer

  3. The Natural Selection of Herpesviruses and Virus-Specific NK Cell Receptors

    Directory of Open Access Journals (Sweden)

    Joseph C. Sun

    2009-10-01

    Full Text Available During the co-evolution of cytomegalovirus (CMV and natural killer (NK cells, each has evolved specific tactics in an attempt to prevail. CMV has evolved multiple immune evasion mechanisms to avoid detection by NK cells and other immune cells, leading to chronic infection. Meanwhile, the host has evolved virus-specific receptors to counter these evasion strategies. The natural selection of viral genes and host receptors allows us to observe a unique molecular example of "survival of the fittest", as virus and immune cells try to out-maneuver one another or for the virus to achieve détente for optimal dissemination in the population.

  4. Multi-cellular natural killer (NK) cell clusters enhance NK cell activation through localizing IL-2 within the cluster

    Science.gov (United States)

    Kim, Miju; Kim, Tae-Jin; Kim, Hye Mi; Doh, Junsang; Lee, Kyung-Mi

    2017-01-01

    Multi-cellular cluster formation of natural killer (NK) cells occurs during in vivo priming and potentiates their activation to IL-2. However, the precise mechanism underlying this synergy within NK cell clusters remains unclear. We employed lymphocyte-laden microwell technologies to modulate contact-mediated multi-cellular interactions among activating NK cells and to quantitatively assess the molecular events occurring in multi-cellular clusters of NK cells. NK cells in social microwells, which allow cell-to-cell contact, exhibited significantly higher levels of IL-2 receptor (IL-2R) signaling compared with those in lonesome microwells, which prevent intercellular contact. Further, CD25, an IL-2R α chain, and lytic granules of NK cells in social microwells were polarized toward MTOC. Live cell imaging of lytic granules revealed their dynamic and prolonged polarization toward neighboring NK cells without degranulation. These results suggest that IL-2 bound on CD25 of one NK cells triggered IL-2 signaling of neighboring NK cells. These results were further corroborated by findings that CD25-KO NK cells exhibited lower proliferation than WT NK cells, and when mixed with WT NK cells, underwent significantly higher level of proliferation. These data highlights the existence of IL-2 trans-presentation between NK cells in the local microenvironment where the availability of IL-2 is limited.

  5. Bcl-2, Bax, and c-Fos expression correlates to RPE cell apoptosis induced by UV-light and daunorubicin

    DEFF Research Database (Denmark)

    Liang, Y G; Jorgensen, A G; Kaestel, C G

    2000-01-01

    PURPOSE. The aim of this study was to determine the role of Bcl-2, Bcl-X L, Bax, and c-Fos in regulation of apoptosis, induced by ultraviolet-light A (UV-A) and daunorubicin (DNR), in retinal pigment epithelium (RPE) cells grown on bovine extracellular matrix (ECM)-coated or uncoated plastic dishes......-A or DNR. This protection was found to be proportionally correlated to the anti-apoptotic protein Bcl-2 and inversely correlated to the expression of Bax. Furthermore a sustained induction and expression of c-Fos was found to correlate to a higher percentage of apoptotic cells of RPE cells grown on plastic...

  6. Aggressive natural killer-cell leukemia: Classical presentation of a rare disease

    Directory of Open Access Journals (Sweden)

    Priya M Jacob

    2014-01-01

    Full Text Available Aggressive natural killer-cell leukaemia is a rare aggressive form of natural killer-cell neoplasm. We report a case of a 40-year-old male who presented with jaundice, raised blood counts,generalised lymphadenopathy and hepatosplenomegaly. The diagnosis was established by flow cytometric analysis of bone marrow aspirate. The patient, however, succumbed to his illness within 2 weeks of starting chemotherapy. To the best of our knowledge, this is the third reported case from India.

  7. X-linked inhibitor of apoptosis regulates T cell effector function

    DEFF Research Database (Denmark)

    Zehntner, Simone P; Bourbonnière, Lyne; Moore, Craig S

    2007-01-01

    To understand how the balance between pro- and anti-apoptotic signals influences effector function in the immune system, we studied the X-linked inhibitor of apoptosis (XIAP), an endogenous regulator of cellular apoptosis. Real-time PCR showed increased XIAP expression in blood of mice...... and oligodendrocytes were not affected; neither did apoptosis increase in liver, where XIAP knockdown also occurred. ASO-XIAP increased susceptibility of T cells to activation-induced apoptosis in vitro. Our results identify XIAP as a critical controller of apoptotic susceptibility of effector T cell function...

  8. ALG-2 knockdown in HeLa cells results in G2/M cell cycle phase accumulation and cell death

    DEFF Research Database (Denmark)

    Høj, Berit Rahbek; la Cour, Peter Jonas Marstrand; Mollerup, Jens

    2009-01-01

    downregulation induces accumulation of HeLa cells in the G2/M cell cycle phase and increases the amount of early apoptotic and dead cells. Caspase inhibition by the pan-caspase inhibitor zVAD-fmk attenuated the increase in the amount of dead cells following ALG-2 downregulation. Thus, our results indicate...... that ALG-2 has an anti-apoptotic function in HeLa cells by facilitating the passage through checkpoints in the G2/M cell cycle phase.......ALG-2 (apoptosis-linked gene-2 encoded protein) has been shown to be upregulated in a variety of human tumors questioning its previously assumed pro-apoptotic function. The aim of the present study was to obtain insights into the role of ALG-2 in human cancer cells. We show that ALG-2...

  9. Role of the endothelin axis in astrocyte- and endothelial cell-mediated chemoprotection of cancer cells

    Science.gov (United States)

    Kim, Seung Wook; Choi, Hyun Jin; Lee, Ho-Jeong; He, Junqin; Wu, Qiuyu; Langley, Robert R.; Fidler, Isaiah J.; Kim, Sun-Jin

    2014-01-01

    Background Recent evidence suggests that astrocytes protect cancer cells from chemotherapy by stimulating upregulation of anti-apoptotic genes in those cells. We investigated the possibility that activation of the endothelin axis orchestrates survival gene expression and chemoprotection in MDA-MB-231 breast cancer cells and H226 lung cancer cells. Methods Cancer cells, murine astrocytes, and murine fibroblasts were grown in isolation, and expression of endothelin (ET) peptides and ET receptors (ETAR and ETBR) compared with expression on cancer cells and astrocytes (or cancer cells and fibroblasts) that were co-incubated for 48 hours. Type-specific endothelin receptor antagonists were used to evaluate the contribution of ETAR and ETBR to astrocyte-induced activation of the protein kinase B (AKT)/mitogen-activated protein kinase (MAPK) signal transduction pathways, anti-apoptotic gene expression, and chemoprotection of cancer cells. We also investigated the chemoprotective potential of brain endothelial cells and microglial cells. Results Gap junction signaling between MDA-MB-231 cancer cells and astrocytes stimulates upregulation of interleukin 6 (IL-6) and IL-8 expression in cancer cells, which increases ET-1 production from astrocytes and ET receptor expression on cancer cells. ET-1 signals for activation of AKT/MAPK and upregulation of survival proteins that protect cancer cells from taxol. Brain endothelial cell-mediated chemoprotection of cancer cells also involves endothelin signaling. Dual antagonism of ETAR and ETBR is required to abolish astrocyte- and endothelial cell-mediated chemoprotection. Conclusions Bidirectional signaling between astrocytes and cancer cells involves upregulation and activation of the endothelin axis, which protects cancer cells from cytotoxicity induced by chemotherapeutic drugs. PMID:25008093

  10. Animal model of naturally occurring bladder cancer: Characterization of four new canine transitional cell carcinoma cell lines

    OpenAIRE

    Rathore, Kusum; Cekanova, Maria

    2014-01-01

    Background Development and further characterization of animal models for human cancers is important for the improvement of cancer detection and therapy. Canine bladder cancer closely resembles human bladder cancer in many aspects. In this study, we isolated and characterized four primary transitional cell carcinoma (K9TCC) cell lines to be used for future in vitro validation of novel therapeutic agents for bladder cancer. Methods Four K9TCC cell lines were established from naturally-occurring...

  11. Prediction of cancer cell sensitivity to natural products based on genomic and chemical properties

    Directory of Open Access Journals (Sweden)

    Zhenyu Yue

    2015-11-01

    Full Text Available Natural products play a significant role in cancer chemotherapy. They are likely to provide many lead structures, which can be used as templates for the construction of novel drugs with enhanced antitumor activity. Traditional research approaches studied structure-activity relationship of natural products and obtained key structural properties, such as chemical bond or group, with the purpose of ascertaining their effect on a single cell line or a single tissue type. Here, for the first time, we develop a machine learning method to comprehensively predict natural products responses against a panel of cancer cell lines based on both the gene expression and the chemical properties of natural products. The results on two datasets, training set and independent test set, show that this proposed method yields significantly better prediction accuracy. In addition, we also demonstrate the predictive power of our proposed method by modeling the cancer cell sensitivity to two natural products, Curcumin and Resveratrol, which indicate that our method can effectively predict the response of cancer cell lines to these two natural products. Taken together, the method will facilitate the identification of natural products as cancer therapies and the development of precision medicine by linking the features of patient genomes to natural product sensitivity.

  12. Involvement of extrinsic and intrinsic apoptotic pathways together with endoplasmic reticulum stress in cell death induced by naphthylchalcones in a leukemic cell line: advantages of multi-target action.

    Science.gov (United States)

    Winter, Evelyn; Chiaradia, Louise Domeneghini; Silva, Adny Henrique; Nunes, Ricardo José; Yunes, Rosendo Augusto; Creczynski-Pasa, Tânia Beatriz

    2014-08-01

    Chalcones, naturally occurring open-chain flavonoids abundant in plants, have demonstrated anticancer activity in multiple tumor cells. In a previous work, the potential anticancer activity of three naphthylchalcones named R7, R13 and R15 was shown. In this study, the mechanism of actions of these chalcones was originally shown. The chalcones presented concentration and time-dependent cytotoxicity. To determine the type of cell death induced by chalcones, we assessed a series of assays including measurements of the caspase-8, -9 and -12 activities, expression of important apoptosis-related genes and proteins, changes in the cell calcium concentration and cytochrome c release. The activities of caspase-8, -9 and -12 increased after the treatment of L1210 cells with the three compounds. Chalcones R7 and R13 induced an increase of pro-apoptotic proteins Bax, Bid and Bak (only chalcone R13), as well as a decrease in anti-apoptotic Bcl-2 expression. These chalcones also induced an increase in Fas and a decrease in p21 and p53 expression. Chalcone R15 seems to act by a different mechanism to promote cell death, as it did not change the mitochondrion-related proteins, nor did it induce the cytochrome c release. All compounds induced an increase in cell calcium concentration and an increase in CHOP expression, which together with an increase in caspase-12 activity, suggest that chalcones could induce an endoplasmic reticulum (ER) stress. Taken together, these results suggest that chalcones induce apoptosis by different pathways, being an interesting strategy to suggest for cancer therapy. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. Lifestyles and mental health status are associated with natural killer cell and lymphokine-activated killer cell activities.

    Science.gov (United States)

    Morimoto, K; Takeshita, T; Inoue-Sakurai, C; Maruyama, S

    2001-04-10

    We investigated the association of lifestyle and mental health status with natural killer (NK) cell and lymphokine-activated killer (LAK) cell activities in healthy males. NK cell activity was determined in 105 male workers and LAK cell activity was determined in 54 male workers. Peripheral blood was obtained from each subject and peripheral blood mononuclear cells (PBMC) were isolated from the blood. These PBMC were used as effector cells. LAK cells were generated by incubation of PBMC with interleukin-2 for 72 h. NK cell activity against NK-sensitive K562 cells and LAK cell activity against NK-resistant Raji cells were examined by 51Cr release assay. Overall lifestyles were evaluated according to the answers on a questionnaire regarding eight health practices (cigarette smoking, alcohol consumption, eating breakfast, hours of sleep, hours of work, physical exercise, nutritional balance, mental stress). Subjects with a good overall lifestyle showed significantly higher NK cell (P mental status had significantly lower NK cell activity than those who reported stable mental status. When subjects were divided into four groups by lifestyle and mental health status, subjects who had poor or moderate lifestyle and reported unstable mental status showed the lowest NK cell activity and subjects who had good lifestyle and reported stable mental status showed the highest NK cell activity among four groups.

  14. Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

    Directory of Open Access Journals (Sweden)

    Fu-Nan Cho

    Full Text Available Natural killer (NK cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs, which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

  15. Enhanced cytotoxicity of natural killer cells following the acquisition of chimeric antigen receptors through trogocytosis.

    Science.gov (United States)

    Cho, Fu-Nan; Chang, Tsung-Hsien; Shu, Chih-Wen; Ko, Ming-Chin; Liao, Shuen-Kuei; Wu, Kang-Hsi; Yu, Ming-Sun; Lin, Shyh-Jer; Hong, Ying-Chung; Chen, Chien-Hsun; Hung, Chien-Hui; Chang, Yu-Hsiang

    2014-01-01

    Natural killer (NK) cells have the capacity to target tumors and are ideal candidates for immunotherapy. Viral vectors have been used to genetically modify in vitro expanded NK cells to express chimeric antigen receptors (CARs), which confer cytotoxicity against tumors. However, use of viral transduction methods raises the safety concern of viral integration into the NK cell genome. In this study, we used trogocytosis as a non-viral method to modify NK cells for immunotherapy. A K562 cell line expressing high levels of anti-CD19 CARs was generated as a donor cell to transfer the anti-CD19 CARs onto NK cells via trogocytosis. Anti-CD19 CAR expression was observed in expanded NK cells after these cells were co-cultured for one hour with freeze/thaw-treated donor cells expressing anti-CD19 CARs. Immunofluorescence analysis confirmed the localization of the anti-CD19 CARs on the NK cell surface. Acquisition of anti-CD19 CARs via trogocytosis enhanced NK cell-mediated cytotoxicity against the B-cell acute lymphoblastic leukemia (B-ALL) cell lines and primary B-ALL cells derived from patients. To our knowledge, this is the first report that describes the increased cytotoxicity of NK cells following the acquisition of CARs via trogocytosis. This novel strategy could be a potential valuable therapeutic approach for the treatment of B-cell tumors.

  16. Alloreactive natural killer cells for the treatment of acute myeloid leukemia: from stem cell transplantation to adoptive immunotherapy

    Directory of Open Access Journals (Sweden)

    Loredana eRuggeri

    2015-10-01

    Full Text Available Natural killer cells express activating and inhibitory receptors which recognize MHC class I alleles, termed Killer cell Immunoglobulin-like Receptors (KIRs. Preclinical and clinical data from haploidentical T-cell depleted stem cell transplantation have demonstrated that alloreactive KIR-L mismatched natural killer cells play a major role as effectors against acute myeloid leukemia. Outside the transplantation setting, several reports have proven the safety and feasibility of natural killer cell infusion in acute myeloid leukemia patients and, in some cases, provided evidence that transferred NK cells are functionally alloreactive and may have a role in disease control. Aim of the present work is to briefly summarize the most recent advances in the field by moving from the first preclinical and clinical demonstration of donor NK alloreactivity in the transplantation setting to the most recent attempts of exploiting the use of alloreactive NK cell infusion as a means of adoptive immunotherapy against acute myeloid leukemia. Altogether, these data highlight the pivotal role of NK cells for the development of novel immunological approaches in the clinical management of acute myeloid leukemia.

  17. Natural biased coin encoded in the genome determines cell strategy.

    Science.gov (United States)

    Dorri, Faezeh; Mahini, Hamid; Sharifi-Zarchi, Ali; Totonchi, Mehdi; Tusserkani, Ruzbeh; Pezeshk, Hamid; Sadeghi, Mehdi

    2014-01-01

    Decision making at a cellular level determines different fates for isogenic cells. However, it is not yet clear how rational decisions are encoded in the genome, how they are transmitted to their offspring, and whether they evolve and become optimized throughout generations. In this paper, we use a game theoretic approach to explain how rational decisions are made in the presence of cooperators and competitors. Our results suggest the existence of an internal switch that operates as a biased coin. The biased coin is, in fact, a biochemical bistable network of interacting genes that can flip to one of its stable states in response to different environmental stimuli. We present a framework to describe how the positions of attractors in such a gene regulatory network correspond to the behavior of a rational player in a competing environment. We evaluate our model by considering lysis/lysogeny decision making of bacteriophage lambda in E. coli.

  18. Natural bizbenzoquinoline derivatives protect zebrafish lateral line sensory hair cells from aminoglycoside toxicity

    Directory of Open Access Journals (Sweden)

    Matthew eKruger

    2016-03-01

    Full Text Available Moderate to severe hearing loss affects 360 million people worldwide and most often results from damage to sensory hair cells. Hair cell damage can result from aging, genetic mutations, excess noise exposure, and certain medications including aminoglycoside antibiotics. Aminoglycosides are effective at treating infections associated with cystic fibrosis and other life-threatening conditions such as sepsis, but cause hearing loss in 20-30% of patients. It is therefore imperative to develop new therapies to combat hearing loss and allow safe use of these potent antibiotics. We approach this drug discovery question using the larval zebrafish lateral line because zebrafish hair cells are structurally and functionally similar to mammalian inner ear hair cells and respond similarly to toxins. We screened a library of 502 natural compounds in order to identify novel hair cell protectants. Our screen identified four bisbenzylisoquinoline derivatives: berbamine, E6 berbamine, hernandezine, and isotetrandrine, each of which robustly protected hair cells from aminoglycoside-induced damage. Using fluorescence microscopy and electrophysiology, we demonstrated that the natural compounds confer protection by reducing antibiotic uptake into hair cells and showed that hair cells remain functional during and after incubation in E6 berbamine. We also determined that these natural compounds do not reduce antibiotic efficacy. Together, these natural compounds represent a novel source of possible otoprotective drugs that may offer therapeutic options for patients receiving aminoglycoside treatment.

  19. Inhibition of natural killer cell-mediated cytotoxicity by lipids extracted from Mycobacterium bovis BCG

    NARCIS (Netherlands)

    Roozemond, R. C.; Halperin, M.; Das, P. K.

    1985-01-01

    Several studies have demonstrated an augmentation of natural killer (NK) cell-mediated cytotoxicity by various adjuvants including BCG. Inhibitory effects of BCG have also been reported, particularly for relatively high doses. Because the cell wall of Mycobacterium bovis BCG contains a high

  20. Carotenoids located in human lymphocyte subpopulations and Natural Killer cells by Raman microspectroscopy

    NARCIS (Netherlands)

    Puppels, G.J.; Puppels, G.J.; Garritsen, H.S.P.; Garritsen, H.S.P.; Kummer, J.A.; Greve, Jan

    1993-01-01

    The presence and subcellular location of carotenoids in human lymphocyte sub-populations (CD4+, CD8+, T-cell receptor-γδ+, and CD19+ ) and natural killer cells (CD16+ ) were studied by means of Raman microspectroscopy. In CD4+ lymphocytes a high concentration (10-3M) of carotenoids was found in the

  1. The Natural Killer Cell Cytotoxic Function Is Modulated by HIV-1 Accessory Proteins

    Directory of Open Access Journals (Sweden)

    Edward Barker

    2011-07-01

    Full Text Available Natural killer (NK cells’ major role in the control of viruses is to eliminate established infected cells. The capacity of NK cells to kill virus-infected cells is dependent on the interactions between ligands on the infected cell and receptors on the NK cell surface. Because of the importance of ligand-receptor interactions in modulating the NK cell cytotoxic response, HIV has developed strategies to regulate various NK cell ligands making the infected cell surprisingly refractory to NK cell lysis. This is perplexing because the HIV-1 accessory protein Vpr induces expression of ligands for the NK cell activating receptor, NKG2D. In addition, the accessory protein Nef removes the inhibitory ligands HLA-A and -B. The reason for the ineffective killing by NK cells despite the strong potential to eliminate infected cells is due to HIV-1 Vpu’s ability to down modulate the co-activation ligand, NTB-A, from the cell surface. Down modulation of NTB-A prevents efficient NK cell degranulation. This review will focus on the mechanisms through which the HIV-1 accessory proteins modulate their respective ligands, and its implication for NK cell killing of HIV-infected cells.

  2. Induction of proliferation in vitro of resting human natural killer cells

    International Nuclear Information System (INIS)

    London, L.

    1986-01-01

    Experiments examined the cellular and humoral factors necessary to induce proliferation of purified NK cells in vitro and analyzed the phenotypic characteristics of these proliferating cells. The authors experiments demonstrated that NK cells do not proliferate in response to typical T cell mitogens or to allogeneic stimulation. However, NK cells are readily induced to proliferate in response to either natural or recombinant IL-2. The proliferative response of NK cells to IL-2 is enhanced in the presence of irradiated B lymphoblastoid ell lines. Proliferating NK cells maintain the expression of surface markers characteristic of freshly isolated NK cells which newly expressing surface activation antigens including the IL-2 and transferric receptors and the HLA-DR antigen. The majority of NK cells initiate proliferation in response to IL-2. Greater than 50 U/ml of IL-2 is necessary to induce maximal tritiated thymidine ( 3 H-TdR) incorporation by NK cells, and the interaction of IL-2 with the Tac IL-2 receptor is required for the maintenance of NK cell proliferation. NK cells do not proliferate in response to irradiated Daudi cells alone, which, in the presence of IL-2, may act by maintaining continuous proliferation of the cells originally responsive to IL-2. Unlike NK cells, the authors have shown that only a minor subset of T cells proliferate in response to IL-2 alone

  3. The anti-canine distemper virus activities of ex vivo-expanded canine natural killer cells.

    Science.gov (United States)

    Park, Ji-Yun; Shin, Dong-Jun; Lee, Soo-Hyeon; Lee, Je-Jung; Suh, Guk-Hyun; Cho, Duck; Kim, Sang-Ki

    2015-04-17

    Natural killer (NK) cells play critical roles in induction of antiviral effects against various viruses of humans and animals. However, few data on NK cell activities during canine distemper virus (CDV) infections are available. Recently, we established a culture system allowing activation and expansion of canine non-B, non-T, large granular NK lymphocytes from PBMCs of normal dogs. In the present study, we explored the ability of such expanded NK cells to inhibit CDV infection in vitro. Cultured CD3-CD5-CD21- NK cells produced large amounts of IFN-γ, exhibited highly upregulated expression of mRNAs encoding NK-cell-associated receptors, and demonstrated strong natural killing activity against canine tumor cells. Although the expanded NK cells were dose-dependently cytotoxic to both normal and CDV-infected Vero cells, CDV infection rendered Vero cells more susceptible to NK cells. Pretreatment with anti-CDV serum from hyperimmunized dogs enhanced the antibody-dependent cellular cytotoxicity (ADCC) of NK cells against CDV-infected Vero cells. The culture supernatants of NK cells, added before or after infection, dose-dependently inhibited both CDV replication and development of CDV-induced cytopathic effects (CPEs) in Vero cells. Anti-IFN-γ antibody neutralized the inhibitory effects of NK cell culture supernatants on CDV replication and CPE induction in Vero cells. Such results emphasize the potential significance of NK cells in controlling CDV infection, and indicate that NK cells may play roles both during CDV infection and in combating such infections, under certain conditions. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Ribosome-mediated synthesis of natural product-like peptides via cell-free translation.

    Science.gov (United States)

    Maini, Rumit; Umemoto, Shiori; Suga, Hiroaki

    2016-10-01

    Peptide natural products (PNPs) represent a unique class of compounds known for their fascinating structural motifs with important biological activities. Lately, PNPs have garnered a lot of interest for their application in drug discovery. Nevertheless, lack of diversity oriented synthetic/biosynthetic platforms to generate large natural product-like libraries has limited their development as peptide therapeutics. The promiscuity of cell-free translation has allowed for the synthesis of artificial PNPs having complex structural features. Modified cell-free translation systems coupled with the display technologies have generated diverse natural product-like peptide libraries and led to the discovery of several biologically active molecules. Such technologies have drastically decreased the time to obtain peptide drug leads and therefore, revolutionized the field of peptide drug discovery. In this account, we review recent developments in the synthesis of natural product-like peptides via cell-free translation. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

    OpenAIRE

    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 ...

  6. Application of Mass Cytometry (CyTOF) for Functional and Phenotypic Analysis of Natural Killer Cells.

    Science.gov (United States)

    Kay, Alexander W; Strauss-Albee, Dara M; Blish, Catherine A

    2016-01-01

    Mass cytometry is a novel platform for high-dimensional phenotypic and functional analysis of single cells. This system uses elemental metal isotopes conjugated to monoclonal antibodies to evaluate up to 42 parameters simultaneously on individual cells with minimal overlap between channels. The platform can be customized for analysis of both phenotypic and functional markers. Here, we will describe methods to stain, collect, and analyze intracellular functional markers and surface phenotypic markers on natural killer cells.

  7. Human NKp44+IL-22+ cells and LTi-like cells constitute a stable RORC+ lineage distinct from conventional natural killer cells

    NARCIS (Netherlands)

    Crellin, Natasha K.; Trifari, Sara; Kaplan, Charles D.; Cupedo, Tom; Spits, Hergen

    2010-01-01

    Lymphoid tissue inducer (LTi) cells are required for lymph node formation during fetal development, and recent evidence implies a role in mucosal immunity in the adult. LTi cells share some phenotypic features of conventional natural killer (NK; cNK) cells; however, little is known to date about the

  8. natural

    Directory of Open Access Journals (Sweden)

    Elías Gómez Macías

    2006-01-01

    Full Text Available Partiendo de óxido de magnesio comercial se preparó una suspensión acuosa, la cual se secó y calcinó para conferirle estabilidad térmica. El material, tanto fresco como usado, se caracterizó mediante DRX, área superficial BET y SEM-EPMA. El catalizador mostró una matriz de MgO tipo periclasa con CaO en la superficie. Las pruebas de actividad catalítica se efectuaron en lecho fijo empacado con partículas obtenidas mediante prensado, trituración y clasificación del material. El flujo de reactivos consistió en mezclas gas natural-aire por debajo del límite inferior de inflamabilidad. Para diferentes flujos y temperaturas de entrada de la mezcla reactiva, se midieron las concentraciones de CH4, CO2 y CO en los gases de combustión con un analizador de gases tipo infrarrojo no dispersivo (NDIR. Para alcanzar conversión total de metano se requirió aumentar la temperatura de entrada al lecho a medida que se incrementó el flujo de gases reaccionantes. Los resultados obtenidos permiten desarrollar un sistema de combustión catalítica de bajo costo con un material térmicamente estable, que promueva la alta eficiencia en la combustión de gas natural y elimine los problemas de estabilidad, seguridad y de impacto ambiental negativo inherentes a los procesos de combustión térmica convencional.

  9. Mesenchymal stem cell-conditioned medium prevents radiation-induced liver injury by inhibiting inflammation and protecting sinusoidal endothelial cells

    International Nuclear Information System (INIS)

    Chen Yixing; Zeng Zhaochong; Sun Jing; Huang Yan; Zhang Zhenyu; Zeng Haiying

    2015-01-01

    Current management of radiation-induced liver injury is limited. Sinusoidal endothelial cell (SEC) apoptosis and inflammation are considered to be initiating events in hepatic damage. We hypothesized that mesenchymal stem cells (MSCs) possess anti-apoptotic and anti-inflammatory actions during hepatic irradiation, acting via paracrine mechanisms. This study aims to examine whether MSC-derived bioactive components are protective against radiation-induced liver injury in rats. MSC-conditioned medium (MSC-CM) was generated from rat bone marrow–derived MSCs. The effect of MSC-CM on the viability of irradiated SECs was examined by flow cytometric analysis. Activation of the Akt and ERK pathways was analyzed by western blot. MSC-CM was also delivered to Sprague–Dawley rats immediately before receiving liver irradiation, followed by testing for pathological features, changes in serum hyaluronic acid, ALT, and inflammatory cytokine levels, and liver cell apoptosis. MSC-CM enhanced the viability of irradiated SECs in vitro and induced Akt and ERK phosphorylation in these cells. Infusion of MSC-CM immediately before liver irradiation provided a significant anti-apoptotic effect on SECs and improved the histopathological features of injury in the irradiated liver. MSC-CM also reduced the secretion and expression of inflammatory cytokines and increased the expression of anti-inflammatory cytokines. MSC-derived bioactive components could be a novel therapeutic approach for treating radiation-induced liver injury. (author)

  10. Therapeutic potential and challenges of Natural killer cells in treatment of solid tumors

    Directory of Open Access Journals (Sweden)

    Andrea eGras Navarro

    2015-04-01

    Full Text Available 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 (CSCs 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.

  11. Argos induces programmed cell death in the developing Drosophila eye by inhibition of the Ras pathway.

    Science.gov (United States)

    Sawamoto, K; Taguchi, A; Hirota, Y; Yamada, C; Jin, M H; Okano, H

    1998-04-01

    We studied the role of Ras signaling in the regulation of cell death during Drosophila eye development. Overexpression of Argos, a diffusible inhibitor of the EGF receptor and Ras signaling, caused excessive cell death in developing eyes at pupal stages. The Argos-induced cell death was suppressed by coexpression of the anti-apoptotic genes p35, diap1, or diap2 in the eye as well as by the Df(3L)H99 chromosomal deletion that lacks three apoptosis-inducing genes, reaper, head involution defective (hid) and grim. Transient misexpression of the activated Ras1 protein (Ras1V12) later in pupal development suppressed the Argos-induced cell death. Thus, Argos-induced cell death seemed to have resulted from the suppression of the anti-apoptotic function of Ras. Conversely, cell death induced by overexpression of Hid was suppressed by gain-of-function mutations of the genes coding for MEK and ERK. These results support the idea that Ras signaling functions in two distinct processes during eye development, first triggering the recruitment of cells and later negatively regulating cell death.

  12. Regorafenib Induces Apoptosis and Inhibits Metastatic Potential of Human Bladder Carcinoma Cells.

    Science.gov (United States)

    Hsu, Fei-Ting; Sun, Cho-Chin; Wu, Chia-Hsing; Lee, Yen-Ju; Chiang, Chih-Hung; Wang, Wei-Shu

    2017-09-01

    The aim of the present study was to verify the effects of regorafenib on apoptosis and metastatic potential in TSGH 8301 human bladder carcinoma cells in vitro. Cells were treated with different concentration of regorafenib for different periods of time. Effects of regorafenib on cell viability, apoptosis pathways, metastatic potential, and expression of metastatic and anti-apoptotic proteins were evaluated with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay, flow cytometry, cell migration and invasion assay, and western blotting. We found regorafenib significantly reduced cell viability, cell migration and invasion, and expression of metastatic and anti-apoptotic proteins. In addition, regorafenib significantly induced accumulation of sub-G 1 phase cells, loss of mitochondrial membrane potential, and expression of active caspase-3 and caspase-8. These results show that regorafenib not only induces apoptosis, but also inhibits metastatic potential in bladder cancer TSGH 8301 cells in vitro. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  13. HIV infection of naturally occurring and genetically reprogrammed human regulatory T-cells.

    Directory of Open Access Journals (Sweden)

    Kyra Oswald-Richter

    2004-07-01

    Full Text Available A T-cell subset, defined as CD4(+CD25(hi (regulatory T-cells [Treg cells], was recently shown to suppress T-cell activation. We demonstrate that human Treg cells isolated from healthy donors express the HIV-coreceptor CCR5 and are highly susceptible to HIV infection and replication. Because Treg cells are present in very few numbers and are difficult to expand in vitro, we genetically modified conventional human T-cells to generate Treg cells in vitro by ectopic expression of FoxP3, a transcription factor associated with reprogramming T-cells into a Treg subset. Overexpression of FoxP3 in naïve human CD4(+ T-cells recapitulated the hyporesponsiveness and suppressive function of naturally occurring Treg cells. However, FoxP3 was less efficient in reprogramming memory T-cell subset into regulatory cells. In addition, FoxP3-transduced T-cells also became more susceptible to HIV infection. Remarkably, a portion of HIV-positive individuals with a low percentage of CD4(+ and higher levels of activated T-cells have greatly reduced levels of FoxP3(+CD4(+CD25(hi T-cells, suggesting disruption of the Treg cells during HIV infection. Targeting and disruption of the T-cell regulatory system by HIV may contribute to hyperactivation of conventional T-cells, a characteristic of HIV disease progression. Moreover, the ability to reprogram human T-cells into Treg cells in vitro will greatly aid in decoding their mechanism of suppression, their enhanced susceptibility to HIV infection, and the unique markers expressed by this subset.

  14. Gene Expression Profiling of the Paracrine Effects of Uterine Natural Killer Cells on Human Endometrial Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Xin Gong

    2014-01-01

    Full Text Available The endometrium contains a population of immune cells that undergo changes during implantation and pregnancy. The majority of these cells are uterine natural killer (uNK cells; however, it is unclear how these cells interact with endometrial epithelial cells. Therefore, we investigated the paracrine effects of the uNK cell-secretion medium on the gene expression profile of endometrial epithelial cells in vitro through microarray analysis. Our results, which were verified by qRT-PCR and western blot, revealed that soluble factors from uNK cells alter the gene expression profiles of epithelial cells. The upregulated genes included interleukin-15 (IL-15 and interleukin-15 receptor alpha (IL-15RA, which result in a loop that stimulates uNK cell proliferation. In addition, vascular endothelial growth factor C (VEGF-C and chemokine (C-X-C motif ligand 10 (CXCL-10 were also determined to be upregulated in epithelial cells, which suggests that uNK cells work synergistically with epithelial cells to support implantation and pregnancy. In addition, oriental herbal medicines have been used to treat infertility since ancient times; however, we failed to find that Zi Dan Yin can regulate these endometrial paracrine effects.

  15. Fate of tumor cells injected into left ventricle of heart in BALB/c mice: role of natural killer cells

    DEFF Research Database (Denmark)

    Basse, P; Hokland, P; Heron, I

    1988-01-01

    of radiolabeled microspheres. Using this technique, we have shown that LV-injected tumor cells, in contrast to iv injected tumor cells, were not arrested in the first capillary bed that they encountered but passed viably through the microvasculature of the brain, heart, kidneys, intestinal tract, and to some......The arrest, retention, and elimination (i.e., clearance) of radiolabeled YAC-1 lymphoma cells injected either iv or into the left ventricle (LV) of the heart were studied in male BALB/c mice, with special emphasis on the role of natural killer (NK) cells. After iv injection YAC-1 cells were...... arrested and, to a large extent, destroyed in the lungs, which contain the first capillary bed that iv injected tumor cells meet. After LV injection the initial distribution of the tumor cells, which depends on the distribution of cardiac output at the time of injection, was estimated by use...

  16. CD40-independent natural killer-cell help promotes dendritic cell vaccine-induced T-cell immunity against endogenous B-cell lymphoma.

    Science.gov (United States)

    Hömberg, Nadine; Adam, Christian; Riedel, Tanja; Brenner, Christoph; Flatley, Andrew; Röcken, Martin; Mocikat, Ralph

    2014-12-15

    It is well established that an interplay between natural killer (NK) cells and dendritic cells (DCs) gives rise to their reciprocal activation and provides a Th1-biased cytokine milieu that fosters antitumor T-cell responses. Ex vivo-differentiated DCs transferred into mice strongly stimulate endogenous NK cells to produce interferon (IFN)-γ and initiate a cascade that eventually leads to cytotoxic T-lymphocyte responses. We show that the ability of exogenous DCs to trigger this pathway obviates CD40 signaling and CD4(+) T-cell help and depends on a preceding maturation step. Importantly, this mechanism was also effective in endogenously arising tumors where IFN-γ production is compromised in contrast to transplantable tumors. In c-myc-transgenic mice developing spontaneous lymphomas, injection of unpulsed DCs caused NK-cell activation and induced CD8(+) T cells capable of recognizing the lymphoma cells. Animals treated with unpulsed DCs showed a survival benefit compared to untreated myc mice. Hence, tumor immunity induced by DC-based vaccines not only depends on specific antigens loaded on the DCs. Rather, DC vaccines generate broader immune responses, because endogenous DCs presenting tumor antigens may also become stimulated by NK cells that were activated by exogenous DCs. Thus, the DC/NK-cell/cytotoxic T lymphocyte axis may commonly have relevance for DC-based vaccination protocols in clinical settings. © 2014 UICC.

  17. Therapeutic manipulation of natural killer (NK) T cells in autoimmunity: are we close to reality?

    Science.gov (United States)

    Simoni, Y; Diana, J; Ghazarian, L; Beaudoin, L; Lehuen, A

    2013-01-01

    T cells reactive to lipids and restricted by major histocompatibility complex (MHC) class I-like molecules represent more than 15% of all lymphocytes in human blood. This heterogeneous population of innate cells includes the invariant natural killer T cells (iNK T), type II NK T cells, CD1a,b,c-restricted T cells and mucosal-associated invariant T (MAIT) cells. These populations are implicated in cancer, infection and autoimmunity. In this review, we focus on the role of these cells in autoimmunity. We summarize data obtained in humans and preclinical models of autoimmune diseases such as primary biliary cirrhosis, type 1 diabetes, multiple sclerosis, systemic lupus erythematosus, rheumatoid arthritis, psoriasis and atherosclerosis. We also discuss the promise of NK T cell manipulations: restoration of function, specific activation, depletion and the relevance of these treatments to human autoimmune diseases. © 2012 The Authors. Clinical and Experimental Immunology © 2012 British Society for Immunology.

  18. Non-canonical programmed cell death mechanisms triggered by natural compounds.

    Science.gov (United States)

    Diederich, Marc; Cerella, Claudia

    2016-10-01

    Natural compounds are the fundament of pharmacological treatments and more than 50% of all anticancer drugs are of natural origins or at least derived from scaffolds present in Nature. Over the last 25 years, molecular mechanisms triggered by natural anticancer compounds were investigated. Emerging research showed that molecules of natural origins are useful for both preventive and therapeutic purposes by targeting essential hallmarks and enabling characteristics described by Hanahan and Weinberg. Moreover, natural compounds were able to change the differentiation status of selected cell types. One of the earliest response of cells treated by pharmacologically active compounds is the change of its morphology leading to ultra-structural perturbations: changes in membrane composition, cytoskeleton integrity, alterations of the endoplasmic reticulum, mitochondria and of the nucleus lead to formation of morphological alterations that are a characteristic of both compound and cancer type preceding cell death. Apoptosis and autophagy were traditionally considered as the most prominent cell death or cell death-related mechanisms. By now multiple other cell death modalities were described and most likely involved in response to chemotherapeutic treatment. It can be hypothesized that especially necrosis-related phenotypes triggered by various treatments or evolving from apoptotic or autophagic mechanisms, provide a more efficient therapeutic outcome depending on cancer type and genetic phenotype of the patient. In fact, the recent discovery of multiple regulated forms of necrosis and the initial elucidation of the corresponding cell signaling pathways appear nowadays as important tools to clarify the immunogenic potential of non-canonical forms of cell death induction. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. A bovine cell line that can be infected by natural sheep scrapie prions.

    Directory of Open Access Journals (Sweden)

    Anja M Oelschlegel

    Full Text Available Cell culture systems represent a crucial part in basic prion research; yet, cell lines that are susceptible to prions, especially to field isolated prions that were not adapted to rodents, are very rare. The purpose of this study was to identify and characterize a cell line that was susceptible to ruminant-derived prions and to establish a stable prion infection within it. Based on species and tissue of origin as well as PrP expression rate, we pre-selected a total of 33 cell lines that were then challenged with natural and with mouse propagated BSE or scrapie inocula. Here, we report the successful infection of a non-transgenic bovine cell line, a sub-line of the bovine kidney cell line MDBK, with natural sheep scrapie prions. This cell line retained the scrapie infection for more than 200 passages. Selective cloning resulted in cell populations with increased accumulation of PrPres, although this treatment was not mandatory for retaining the infection. The infection remained stable, even under suboptimal culture conditions. The resulting infectivity of the cells was confirmed by mouse bioassay (Tgbov mice, Tgshp mice. We believe that PES cells used together with other prion permissive cell lines will prove a valuable tool for ongoing efforts to understand and defeat prions and prion diseases.

  20. Disruption of Survivin in K562 cells elevates telomerase activity and protects cells against apoptosis induced by the Bcr-abl kinase inhibitor STI571

    OpenAIRE

    Wang, Zhanxiang; Pelus, Louis M.

    2008-01-01

    The Bcr-abl kinase inhibitor STI571 produces clinical responses in most patients with Chronic Myeloid Leukemia (CML); however, development of resistance limits utility. One strategy to overcome STI571 resistance is to decrease the level/activity of Bcr-abl. We reported that disruption of the anti-apoptotic protein Survivin promoted STI571-induced apoptosis in Bcr-abl+ K562 cells, through caspase-dependent Bcr-abl degradation. To investigate the utility of Survivin disruption in drug-resistant...

  1. Methotrexate induces poly(ADP-ribose) polymerase-dependent, caspase 3-independent apoptosis in subsets of proliferating CD4+ T cells

    DEFF Research Database (Denmark)

    Nielsen, C H; Albertsen, L; Bendtzen, K

    2007-01-01

    ) cells play a significant role in most AID. We therefore examined directly, by flow cytometry, the uptake of MTX by the T helper (Th) cells stimulated for 6 days with Candida albicans (CA) or tetanus toxoid (TT), and its consequences with respect to induction of apoptosis. While none of the resting Th...... apoptosis in both undivided and divided Th cells. PHA-induced apoptosis involved activation of caspase-3 and the anti-apoptotic protein Bcl-2 in addition to PARP cleavage, suggesting that PHA induces apoptosis via different pathways than CA and TT. We suggest that the latter are more representative...

  2. Natural killer cells: the journey from puzzles in biology to treatment of cancer.

    Science.gov (United States)

    Bodduluru, Lakshmi Narendra; Kasala, Eshvendar Reddy; Madhana, Rajaram Mohan Rao; Sriram, Chandra Shaker

    2015-02-28

    Natural Killer (NK) cells are innate immune effectors that are primarily involved in immunosurveillance to spontaneously eliminate malignantly transformed and virally infected cells without prior sensitization. NK cells trigger targeted attack through release of cytotoxic granules, and secrete various cytokines and chemokines to promote subsequent adaptive immune responses. NK cells selectively attack target cells with diminished major histocompatibility complex (MHC) class I expression. This "Missing-self" recognition by NK cells at first puzzled researchers in the early 1990s, and the mystery was solved with the discovery of germ line encoded killer immunoglobulin receptors that recognize MHC-I molecules. This review summarizes the biology of NK cells detailing the phenotypes, receptors and functions; interactions of NK cells with dendritic cells (DCs), macrophages and T cells. Further we discuss the various strategies to modulate NK cell activity and the practice of NK cells in cancer immunotherapy employing NK cell lines, autologous, allogeneic and genetically engineered cell populations. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  3. Vesicle-associated membrane protein 7 (VAMP-7) is essential for target cell killing in a natural killer cell line

    International Nuclear Information System (INIS)

    Marcet-Palacios, Marcelo; Odemuyiwa, Solomon O.; Coughlin, Jason J.; Garofoli, Daniella; Ewen, Catherine; Davidson, Courtney E.; Ghaffari, Mazyar; Kane, Kevin P.; Lacy, Paige; Logan, Michael R.; Befus, A. Dean; Bleackley, R. Chris; Moqbel, Redwan

    2008-01-01

    Natural killer cells recognize and induce apoptosis in foreign, transformed or virus-infected cells through the release of perforin and granzymes from secretory lysosomes. Clinically, NK-cell mediated killing is a major limitation to successful allo- and xenotransplantation. The molecular mechanisms that regulate the fusion of granzyme B-containing secretory lysosomes to the plasma membrane in activated NK cells, prior to target cell killing, are not fully understood. Using the NK cell line YT-Indy as a model, we have investigated the expression of SNAP REceptors (SNAREs), both target (t-) and vesicular (v-) SNAREs, and their function in granzyme B-mediated target cell killing. Our data showed that YT-Indy cells express VAMP-7 and SNAP-23, but not VAMP-2. VAMP-7 was associated with granzyme B-containing lysosomal granules. Using VAMP-7 small interfering RNA (siRNA), we successfully knocked down the expression of VAMP-7 protein in YT-Indy to less than 10% of untreated cells in 24 h. VAMP7-deficient YT-Indy cells activated via co-culture with Jurkat cells released <1 ng/mL of granzyme B, compared to 1.5-2.5 μg/mL from controls. Using Jurkat cells as targets, we showed a 7-fold reduction in NK cell-mediated killing by VAMP-7 deficient YT-Indy cells. Our results show that VAMP-7 is a crucial component of granzyme B release and target cell killing in the NK cell line YT-Indy. Thus, targeting VAMP-7 expression specifically with siRNA, following transplantation, may be a viable strategy for preventing NK cell-mediated transplant rejection, in vivo

  4. On natural frequencies of non-uniform beams modulated by finite periodic cells

    International Nuclear Information System (INIS)

    Xu, Yanlong; Zhou, Xiaoling; Wang, Wei; Wang, Longqi; Peng, Fujun; Li, Bin

    2016-01-01

    It is well known that an infinite periodic beam can support flexural wave band gaps. However, in real applications, the number of the periodic cells is always limited. If a uniform beam is replaced by a non-uniform beam with finite periodicity, the vibration changes are vital by mysterious. This paper employs the transfer matrix method (TMM) to study the natural frequencies of the non-uniform beams with modulation by finite periodic cells. The effects of the amounts, cross section ratios, and arrangement forms of the periodic cells on the natural frequencies are explored. The relationship between the natural frequencies of the non-uniform beams with finite periodicity and the band gap boundaries of the corresponding infinite periodic beam is also investigated. Numerical results and conclusions obtained here are favorable for designing beams with good vibration control ability. - Highlights: • The transfer matrix method to study the natural frequencies of the finite periodic non-uniform beams is derived. • The transfer matrix method to study the band gaps of the infinite periodic non-uniform beams is derived. • The effects of the periodic cells on the natural frequencies are explored. • The relationships of the natural frequencies and band gap boundaries are investigated.

  5. Chemotherapeutic drugs sensitize human renal cell carcinoma cells to ABT-737 by a mechanism involving the Noxa-dependent inactivation of Mcl-1 or A1

    Directory of Open Access Journals (Sweden)

    Zantl Niko

    2010-06-01

    Full Text Available Abstract Background Human renal cell carcinoma (RCC is very resistant to chemotherapy. ABT-737 is a novel inhibitor of anti-apoptotic proteins of the Bcl-2 family that has shown promise in various preclinical tumour models. Results We here report a strong over-additive pro-apoptotic effect of ABT-737 and etoposide, vinblastine or paclitaxel but not 5-fluorouracil in cell lines from human RCC. ABT-737 showed very little activity as a single agent but killed RCC cells potently when anti-apoptotic Mcl-1 or, unexpectedly, A1 was targeted by RNAi. This potent augmentation required endogenous Noxa protein since RNAi directed against Noxa but not against Bim or Puma reduced apoptosis induction by the combination of ABT-737 and etoposide or vinblastine. At the level of mitochondria, etoposide-treatment had a similar sensitizing activity and allowed for ABT-737-induced release of cytochrome c. Conclusions Chemotherapeutic drugs can overcome protection afforded by Mcl-1 and A1 through endogenous Noxa protein in RCC cells, and the combination of such drugs with ABT-737 may be a promising strategy in RCC. Strikingly, A1 emerged in RCC cell lines as a protein of similar importance as the well-established Mcl-1 in protection against apoptosis in these cells.

  6. Lidocaine Stimulates the Function of Natural Killer Cells in Different Experimental Settings.

    Science.gov (United States)

    Cata, Juan P; Ramirez, Maria F; Velasquez, Jose F; Di, A I; Popat, Keyuri U; Gottumukkala, Vijaya; Black, Dahlia M; Lewis, Valerae O; Vauthey, Jean N

    2017-09-01

    One of the functions of natural killer (NK) cells is to eliminate cancer cells. The cytolytic activity of NK cells is tightly regulated by inhibitory and activation receptors located in the surface membrane. Lidocaine stimulates the function of NK cells at clinically relevant concentrations. It remains unknown whether this effect of lidocaine has an impact on the expression of surface receptors of NK cells, can uniformly stimulate across different cancer cell lines, and enhances the function of cells obtained during oncological surgery. NK cells from healthy donors and 43 patients who had undergone surgery for cancer were isolated. The function of NK cells was measured by lactate dehydrogenase release assay. NK cells were incubated with clinically relevant concentrations of lidocaine. By flow cytometry, we determined the impact of lidocaine on the expression of galactosylgalactosylxylosylprotein3-beta-glucuronosytranferase 1, marker of cell maturation (CD57), killer cell lectin like receptor A, inhibitory (NKG2A) receptors and killer cell lectin like receptor D, activation (NKG2D) receptors of NK cells. Differences in expression at pLidocaine increased the expression of NKG2D receptors and stimulated the function of NK cells against ovarian, pancreatic and ovarian cancer cell lines. Lidocaine also increased the cytolytic activity of NK cells from patients who underwent oncological surgery, except for those who had orthopedic procedures. Lidocaine showed an important stimulatory activity on NK cells. Our findings suggest that lidocaine might be used perioperatively to minimize the impact of surgery on NK cells. Copyright© 2017, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  7. In vitro atrazine-exposure inhibits human natural killer cell lytic granule release

    International Nuclear Information System (INIS)

    Rowe, Alexander M.; Brundage, Kathleen M.; Barnett, John B.

    2007-01-01

    The herbicide atrazine is a known immunotoxicant and an inhibitor of human natural killer (NK) cell lytic function. The precise changes in NK cell lytic function following atrazine exposure have not been fully elucidated. The current study identifies the point at which atrazine exerts its affect on the stepwise process of human NK cell-mediated lyses of the K562 target cell line. Using intracellular staining of human peripheral blood lymphocytes, it was determined that a 24-h in vitro exposure to atrazine did not decrease the level of NK cell lytic proteins granzyme A, granzyme B or perforin. Thus, it was hypothesized that atrazine exposure was inhibiting the ability of the NK cells to bind to the target cell and subsequently inhibit the release of lytic protein from the NK cell. To test this hypothesis, flow cytometry and fluorescent microscopy were employed to analyze NK cell-target cell co-cultures following atrazine exposure. These assays demonstrated no significant decrease in the level of target cell binding. However, the levels of NK intracellular lytic protein retained and the amount of lytic protein released were assessed following a 4-h incubation with K562 target cells. The relative level of intracellular lytic protein was 25-50% higher, and the amount of lytic protein released was 55-65% less in atrazine-treated cells than vehicle-treated cells following incubation with the target cells. These results indicate that ATR exposure inhibits the ability of NK cells to lyse target cells by blocking lytic granule release without affecting the ability of the NK cell to form stable conjugates with target cells

  8. Physical, biologic, and phenotypic properties of natural regulatory cells in murine bone marrow

    International Nuclear Information System (INIS)

    Dorshkind, K.; Rosse, C.

    1982-01-01

    A lymphocyte-enriched fraction of murine bone marrow (BML) contains natural regulatory cells (NRC) that can inhibit, on a dose-dependent basis, proliferative and cytotoxic responses to alloantigens in a mixed lymphocyte culture. The objective of this study was to investigate the characteristics of the cells responsible for this phenomenon in CBA mice. Maximal suppression was obtained with BML cells themselves rather than cell products. Light-scatter analysis of NRC on the fluorescence-activated cell sorter demonstrated them to be larger than small lymphocytes, and their sedimentation in discontinuous Percoll gradients showed the cells to be of heterogeneous density. This heterogeneity is further reflected by the fact that both plastic adherent and nonadherent BML are suppressive. NRC must be viable in order to mediate suppression; they are cortisone-resistant and are not affected by doses of gamma irradiation up to 1,000 R. NRC are not T or B lymphocytes or Ia-bearing macrophages. The involvement of mature granulocytes and macrophages in natural suppression is unlikely in that NRC do not bear Fc receptors. Elimination of cells from BML with the natural killer (NK) surface marker Asialo GM1 does not abrogate suppression. NRC are capable of mediating suppression across major and minor histocompatibility complex barriers. While lymphoid cells are prominent in BML, the contamination of this marrow fraction with immature granulocytes and monocytes makes a morphologic identification of NRC difficult. These characteristics are most consistent with NRC begin immature marrow cells of undetermined lineage. The relationship of NRC to naturally occurring marrow suppressor cells described in other systems is not yet clear and awaits experimental clarification

  9. The role of natural killer cells in the early period of infection in murine cutaneous leishmaniasis

    Directory of Open Access Journals (Sweden)

    M.D. Laurenti

    1999-03-01

    Full Text Available In order to study the role of natural killer (NK cells during the early period of Leishmania infection, BALB/c mice were selectively and permanently depleted of NK cells by injection with 90Sr and subsequently infected with Leishmania (Leishmania amazonensis (HSJD-1 strain. 90Sr is known to selectively deplete NK cells, leaving an intact T- and B-cell compartment and preserving the ability to produce both interferon alpha and IL-2. This method of depletion has advantages when compared with depletion using anti-NK cell monoclonal antibodies because the effect is permanent and neither activates complement nor provokes massive cell death. In the present study, after one month of treatment with 90Sr, the depletion of NK cells was shown by a more than ten-fold reduction in the cytotoxic activity of these cells: 2 x 106 spleen cells from NK-depleted animals were required to reach the same specific lysis of target cells effected by 0.15 x 106 spleen cells from normal control animals. The histopathology of the skin lesion at 7 days after Leishmania infection showed more parasites in the NK cell-depleted group. This observation further strengthens a direct role of NK cells during the early period of Leishmania infection.

  10. IL-15 super-agonist (ALT-803) enhances natural killer (NK) cell function against ovarian cancer.

    Science.gov (United States)

    Felices, M; Chu, S; Kodal, B; Bendzick, L; Ryan, C; Lenvik, A J; Boylan, K L M; Wong, H C; Skubitz, A P N; Miller, J S; Geller, M A

    2017-06-01

    Natural killer (NK) cells represent a powerful immunotherapeutic target as they lyse tumors directly, do not require differentiation, and can elicit potent inflammatory responses. The objective of these studies was to use an IL-15 super-agonist complex, ALT-803 (Altor BioScience Corporation), to enhance the function of both normal and ovarian cancer patient derived NK cells by increasing cytotoxicity and cytokine production. NK cell function from normal donor peripheral blood mononuclear cells (PBMCs) and ovarian cancer patient ascites was assessed using flow cytometry and chromium release assays ±ALT-803 stimulation. To evaluate the ability of ALT-803 to enhance NK cell function in vivo against ovarian cancer, we used a MA148-luc ovarian cancer NOD scid gamma (NSG) xenogeneic mouse model with transferred human NK cells. ALT-803 potently enhanced functionality of NK cells against all ovarian cancer cell lines with significant increases seen in CD107a, IFNγ and TNFα expression depending on target cell line. Function was also rescued in NK cells derived from ovarian cancer patient ascites. Finally, only animals treated with intraperitoneal ALT-803 displayed an NK dependent significant decrease in tumor. ALT-803 enhances NK cell cytotoxicity against ovarian cancer in vitro and in vivo and is able to rescue functionality of NK cells derived from ovarian cancer patient ascites. These findings suggest that ALT-803 has the potential to enhance NK cell-based immunotherapeutic approaches for the treatment of ovarian cancer. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Murine cytomegalovirus stimulates natural killer cell function but kills genetically resistant mice treated with radioactive strontium

    International Nuclear Information System (INIS)

    Masuda, A.; Bennett, M.

    1981-01-01

    Treatment of C3H/St mice with 100 microCi of 89Sr weakened their genetic resistance to murine cytomegalovirus (MCMV) infection. The criteria utilized to detect increased susceptibility were: (i) survival of mice; (ii) numbers of MCMV-infected cells in the spleens and liver; and (iii) serum glutamic pyruvic transaminase levels. The natural killer (NK) cell activity of spleen cells from mice treated with 89Sr is very low. However, the NK activities of spleen cells of both normal and 89Sr-treated mice were greatly augmented 3 days after infection with MCMV. These NK cells lysed a variety of tumor cells and shared several features with conventional NK cells, but were not lysed by anti-Nk-1.2 serum (specific for NK cells) plus complement. Splenic adherent cells did not lyse tumor cells themselves but were necessary for the stimulation of NK cells by MCMV. The paradox of high NK cell function and poor survival in 89Sr-treated mice infected with MCMV was a surprise. We conclude that these augmented NK cells, of themselves, cannot account for the genetic resistance of C3H/St mice to infection with MCMV

  12. New Directions for Natural Killer T Cells in the Immunotherapy of Cancer

    Directory of Open Access Journals (Sweden)

    Luc Teyton

    2017-11-01

    Full Text Available Natural killer T (NKT cells have been placed at the interface between innate and adaptive immunity by a long series of experiments that convincingly showed that beyond cytokine secretion and NK cell recruitment, NKT cells were coordinating dendritic cell and B cell maturation through direct membrane contacts and initiate productive responses. As such, NKT cells are the cellular adjuvant of many immune reactions and have functions that go much beyond what their name encapsulates. In addition, the initial discovery of the ligands of NKT cells is deeply linked to cancer biology and therapy. However, for a host of reasons, animal models in which agonists of NKT cells were used did not translate well to human cancers. A systematic reassessment of NKT cells role in tumorigenesis, especially spontaneous one, is now accessible using single cell analysis technologies both in mouse and man, and should be taken advantage of. Similarly, the migration, localization, phenotype of NKT cells following induced expansion after injection of an agonist can be examined at the single cell level. This technological revolution will help evaluate where and how NKT cells can be used in cancer.

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

    Science.gov (United States)

    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.

  14. Navigating barriers: the challenge of directed secretion at the natural killer cell lytic immunological synapse.

    Science.gov (United States)

    Sanborn, Keri B; Orange, Jordan S

    2010-05-01

    Natural killer (NK) cells have an inherent ability to recognize and destroy a wide array of cells rendered abnormal by stress or disease. NK cells can kill a targeted cell by forming a tight interface-the lytic immunological synapse. This represents a dynamic molecular arrangement that over time progresses through a series of steps to ultimately deliver the contents of specialized organelles known as lytic granules. In order to mediate cytotoxicity, the NK cell faces the challenge of mobilizing the lytic granules, polarizing them to the targeted cell, facilitating their approximation to the NK cell membrane, and releasing their contents. This review is focused upon the final steps in accessing function through the lytic immunological synapse.

  15. Exploiting natural killer group 2D receptors for CAR T-cell therapy.

    Science.gov (United States)

    Demoulin, Benjamin; Cook, W James; Murad, Joana; Graber, David J; Sentman, Marie-Louise; Lonez, Caroline; Gilham, David E; Sentman, Charles L; Agaugue, Sophie

    2017-08-01

    Chimeric antigen receptors (CARs) are genetically engineered proteins that combine an extracellular antigen-specific recognition domain with one or several intracellular T-cell signaling domains. When expressed in T cells, these CARs specifically trigger T-cell activation upon antigen recognition. While the clinical proof of principle of CAR T-cell therapy has been established in hematological cancers, CAR T cells are only at the early stages of being explored to tackle solid cancers. This special report discusses the concept of exploiting natural killer cell receptors as an approach that could broaden the specificity of CAR T cells and potentially enhance the efficacy of this therapy against solid tumors. New data demonstrating feasibility of this approach in humans and supporting the ongoing clinical trial are also presented.

  16. Enhanced dopaminergic differentiation of human neural stem cells by synergistic effect of Bcl-xL and reduced oxygen tension

    DEFF Research Database (Denmark)

    Krabbe, Christina; Courtois, Elise; Jensen, Pia

    2009-01-01

    Neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. Here we investigated the effect of the anti-apoptotic protein Bcl-x(L) and oxygen tension on dopaminergic different......Neural stem cells constitute a promising source of cells for transplantation in Parkinson's disease, but a protocol for controlled dopaminergic differentiation is not yet available. Here we investigated the effect of the anti-apoptotic protein Bcl-x(L) and oxygen tension on dopaminergic...... differentiation and survival of a human ventral mesencephalic stem cell line (hVM1). hVM1 cells and a Bcl-x(L) over-expressing subline (hVMbcl-x(L)) were differentiated by sequential treatment with fibroblast growth factor-8, forskolin, sonic hedgehog, and glial cell line-derived neurotrophic factor. After 10......-PCR-analysis revealed expression of several dopaminergic markers besides of TH just as dopamine was detected in the culture medium by HPLC analysis. Although Bcl-x(L)-over-expression reduced cell death in the cultures, it did not alter the relative content of GABAergic, neurons, while the content of astroglial cells...

  17. Toxoplasma gondii inhibits cytochrome c-induced caspase activation in its host cell by interference with holo-apoptosome assembly

    Directory of Open Access Journals (Sweden)

    Kristin Graumann

    2015-05-01

    Full Text Available Inhibition of programmed cell death pathways of mammalian cells often facilitates the sustained survival of intracellular microorganisms. The apicomplexan parasite Toxoplasma gondii is a master regulator of host cell apoptotic pathways. Here, we have characterized a novel anti-apoptotic activity of T. gondii. Using a cell-free cytosolic extract model, we show that T. gondii interferes with the activities of caspase 9 and caspase 3/7 which have been induced by exogenous cytochrome c and dATP. Proteolytic cleavage of caspases 9 and 3 is also diminished suggesting inhibition of holo-apoptosome function. Parasite infection of Jurkat T cells and subsequent triggering of apoptosome formation by exogenous cytochrome c in vitro and in vivo indicated that T. gondii also interferes with caspase activation in infected cells. Importantly, parasite inhibition of cytochrome c-induced caspase activation considerably contributes to the overall anti-apoptotic activity of T. gondii as observed in staurosporine-treated cells. Co-immunoprecipitation showed that T. gondii abolishes binding of caspase 9 to Apaf-1 whereas the interaction of cytochrome c with Apaf-1 remains unchanged. Finally, T. gondii lysate mimics the effect of viable parasites and prevents holo-apoptosome functionality in a reconstituted in vitro system comprising recombinant Apaf-1 and caspase 9. Beside inhibition of cytochrome c release from host cell mitochondria, T. gondii thus also targets the holo-apoptosome assembly as a second mean to efficiently inhibit the caspase-dependent intrinsic cell death pathway.

  18. Immunochemical and ultrastructural assessment of the nature of the pericellular basement membrane of human decidual cells

    DEFF Research Database (Denmark)

    Wewer, U M; Faber, M; Liotta, L A

    1985-01-01

    Human decidual cells of early and late pregnancy were studied immunochemically and ultrastructurally with respect to the presence and nature of pericellular basement membrane material. The most prominent cell type in decidual tissue of both early and late pregnancy were large, mature epithelioid...... of stromal cells into decidual cells of the pregnant endometrium. Predecidualization of the human endometrium, which is seen in the late secretory phase of the normal menstrual cycle and in some states of hyperplasia, was also shown to be accompanied by the presence of deposits of laminin-positive material...

  19. In Vivo Monitoring of Natural Killer Cell Trafficking during Tumor Immunotherapy

    Directory of Open Access Journals (Sweden)

    Naomi S. Sta Maria

    2014-01-01

    Full Text Available Natural killer (NK cells are a crucial part of the innate immune system and play critical roles in host anti-viral, anti-microbial, and anti-tumor responses. The elucidation of NK cell biology and their therapeutic use are actively being pursued with 200 clinical trials currently underway. In this review, we outline the role of NK cells in cancer immunotherapies and summarize current noninvasive imaging technologies used to track NK cells in vivo to investigate mechanisms of action, develop new therapies, and evaluate efficacy of adoptive transfer.

  20. Natural Killer Cells Are Activated by Lactic Acid Bacteria-Matured Dendritic Cells

    DEFF Research Database (Denmark)

    Fink, Lisbeth Nielsen; Christensen, Hanne Risager; Frøkiær, Hanne

    of certain lactic acid bacteria has been shown to increase in vivo NK cytotoxicity. Here, we investigated how human gut flora-derived lactobacilli affect NK cells in vitro, by measuring proliferation and IFN-gamma production of human NK cells upon bacterial stimulation. Human peripheral blood NK cells were....... In contrast, a Lactobacillus paracasei strain caused the NK cells to proliferate only in the presence of monocytes. These results demonstrate that various strains of lactobacilli have the capacity to activate NK cells in vitro, in a monocyte dependent or independent way. Hence, the encounter of NK cells...

  1. Herceptin Enhances the Antitumor Effect of Natural Killer Cells on Breast Cancer Cells Expressing Human Epidermal Growth Factor Receptor-2

    Directory of Open Access Journals (Sweden)

    Xiao Tian

    2017-10-01

    Full Text Available Optimal adoptive cell therapy (ACT should contribute to effective cancer treatment. The unique ability of natural killer (NK cells to kill cancer cells independent of major histocompatibility requirement makes them suitable as ACT tools. Herceptin, an antihuman epidermal growth factor receptor-2 (anti-HER2 monoclonal antibody, is used to treat HER2+ breast cancer. However, it has limited effectiveness and possible severe cardiotoxicity. Given that Herceptin may increase the cytotoxicity of lymphocytes, we explored the possible augmentation of NK cell cytotoxicity against HER2+ breast cancer cells by Herceptin. We demonstrated that Herceptin could interact with CD16 on NK cells to expand the cytotoxic NK (specifically, CD56dim cell population. Additionally, Herceptin increased NK cell migration and cytotoxicity against HER2+ breast cancer cells. In a pilot study, Herceptin-treated NK cells shrunk lung nodular metastasis in a woman with HER2+ breast cancer who could not tolerate the cardiotoxic side effects of Herceptin. Our findings support the therapeutic potential of Herceptin-treated NK cells in patients with HER2+ and Herceptin-intolerant breast cancer.

  2. Dynamic changes of cytotoxic T lymphocytes (CTLs, natural killer (NK cells, and natural killer T (NKT cells in patients with acute hepatitis B infection

    Directory of Open Access Journals (Sweden)

    Liu Bo

    2011-05-01

    Full Text Available Abstract Background The goal of this study is to observe changes in HBcAg-specific cytotoxic T lymphocytes (CTLs, natural killer (NK and natural killer T (NKT cells from peripheral blood and to relate such changes on viral clearance and liver injury in patients with acute hepatitis B (AHB. Methods Dynamic profiles on the frequency of HLA-A0201-restricted HBcAg18-27 pentamer complex (MHC-Pentamer-specific CTLs and lymphocyte subsets in AHB patients were analyzed in addition to liver function tests, HBV serological markers, and HBV DNA levels. ELISPOT was used to detect interferon-gamma (INF-γ secretion in specific CTLs stimulated with known T cell epitope peptides associated with HBV surface protein, polymerase, and core protein. Results HBV-specific CTL frequencies in AHB patients were much higher than in patients with chronic hepatitis B (CHB (p +CD8+ T cell numbers in AHB patients was more than observed in the healthy control group from the first to the fourth week after admission (p = 0.008 and 0.01, respectively; the number of CD3+CD8+ T cells and frequency of HBcAg18-27-specific CTLs in AHB patients reached peak levels at the second week after admission. NK and NKT cell numbers were negatively correlated with the frequency of HBcAg-specific CTLs (r = -0.266, p = 0.05. Conclusions Patients with AHB possess a higher frequency of HBcAg-specific CTLs than CHB patients. The frequency of specific CTLs in AHB patients is correlated with HBeAg clearance indicating that HBV-specific CTLs play an important role in viral clearance and the self-limited process of the disease. Furthermore, NK and NKT cells are likely involved in the early, non-specific immune response to clear the virus.

  3. Dye-Sensitized Solar Cells (DSSCs) reengineering using TiO2 with natural dye (anthocyanin)

    Science.gov (United States)

    Subodro, Rohmat; Kristiawan, Budi; Ramelan, Ari Handono; Wahyuningsih, Sayekti; Munawaroh, Hanik; Hanif, Qonita Awliya; Saputri, Liya Nikmatul Maula Zulfa

    2017-01-01

    This research on Dye-Sensitized Solar Cells (DSSCs) reengineering was carried out using TiO2 with natural dye (anthocyanin). The fabrication of active carbon layer/TiO2 DSSC solar cell was based on natural dye containing anthocyanins such as mangosteen peel, red rose flower, black glutinous rice, and purple eggplant peel. DSSC was prepared with TiO2 thin layer doped with active carbon; Natural dye was analyzed using UV-Vis and TiO2 was analyzed using X-ray diffractometer (XRD), meanwhile scanning electron microscope (SEM) was used to obtain the size of the crystal. Keithley instrument test was carried out to find out I-V characteristics indicating that the highest efficiency occurred in DSSCs solar cell with 24-hour soaking with mangosteen peel 0.00047%.

  4. Amelioration of neurodegenerative diseases by cell death-induced cytoplasmic delivery of humanin.

    Science.gov (United States)

    Park, Tae-Yoon; Kim, Seung-Hyung; Shin, Yoon-Chul; Lee, Nae-Hyun; Lee, Rae-Kyung Christina; Shim, Jae-Hyuck; Glimcher, Laurie H; Mook-Jung, Inhee; Cheong, Eunji; Kim, Won-Ki; Honda, Fumiko; Morio, Tomohiro; Lim, Jong-Soon; Lee, Sang-Kyou

    2013-03-28

    Inhibition of the early intracellular event that triggers neurodegenerative cascades and reversal of neuronal cell death are essential for effective treatment of Alzheimer's disease (AD). In this study, a novel therapeutic for AD, a transducible humanin with an extended caspase-3 cleavage sequence (tHN-C3), was developed and showed multiple mechanisms of therapeutic action. These included targeted delivery of anti-apoptotic protein humanin through the blood-brain barrier (BBB) to neuronal cells, specific inhibition of caspase-3 activation to inhibit the early triggering of AD progression, and delivery of humanin into the cytoplasm of neuronal cells undergoing apoptosis where it exerts its anti-apoptotic functions effectively. The tHN-C3 prevented neuronal cell death induced by H2O2, or soluble Aβ42, via Bax binding. In animal models of AD induced by amyloid beta, in Tg2576 mice, and in the rat middle cerebral artery occlusion model of stroke, tHN-C3 effectively prevented neuronal cell death, inflammatory cell infiltration into the brain, and improved cognitive memory. The therapeutic effectiveness of tHN-C3 was comparable to that of Aricept, a clinically approved drug for AD treatment. Therefore, tHN-C3 may be a new remedy with multiple therapeutic functions targeting the early and late stages of neurodegeneration in AD and other brain injuries. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Natural killer cell biology illuminated by primary immunodeficiency syndromes in humans.

    Science.gov (United States)

    Voss, Matthias; Bryceson, Yenan T

    2017-04-01

    Natural killer (NK) cells are innate immune cytotoxic effector cells well known for their role in antiviral immunity and tumor immunosurveillance. In parts, this knowledge stems from rare inherited immunodeficiency disorders in humans that abrogate NK cell function leading to immune impairments, most notably associated with a high susceptibility to viral infections. Phenotypically, these disorders range from deficiencies selectively affecting NK cells to complex general immune defects that affect NK cells but also other immune cell subsets. Moreover, deficiencies may be associated with reduced NK cell numbers or rather impair specific NK cell effector functions. In recent years, genetic defects underlying the various NK cell deficiencies have been uncovered and have triggered investigative efforts to decipher the molecular mechanisms underlying these disorders. Here we review the associations between inherited human diseases and NK cell development as well as function, with a particular focus on defects in NK cell exocytosis and cytotoxicity. Furthermore we outline how reports of diverse genetic defects have shaped our understanding of NK cell biology. Copyright © 2015. Published by Elsevier Inc.

  6. Invariant Natural Killer T Cells in Immune Regulation of Blood Cancers: Harnessing Their Potential in Immunotherapies

    Directory of Open Access Journals (Sweden)

    Pui Yeng Lam

    2017-10-01

    Full Text Available Invariant natural killer T (iNKT cells are a unique innate T lymphocyte population that possess cytolytic properties and profound immunoregulatory activities. iNKT cells play an important role in the immune surveillance of blood cancers. They predominantly recognize glycolipid antigens presented on CD1d, but their activation and cytolytic activities are not confined to CD1d expressing cells. iNKT cell stimulation and subsequent production of immunomodulatory cytokines serve to enhance the overall antitumor immune response. Crucially, the activation of iNKT cells in cancer often precedes the activation and priming of other immune effector cells, such as NK cells and T cells, thereby influencing the generation and outcome of the antitumor immune response. Blood cancers can evade or dampen iNKT cell responses by downregulating expression of recognition receptors or by actively suppressing or diverting iNKT cell functions. This review will discuss literature on iNKT cell activity and associated dysregulation in blood cancers as well as highlight some of the strategies designed to harness and enhance iNKT cell functions against blood cancers.

  7. Different subsets of natural killer T cells may vary in their roles in health and disease

    Science.gov (United States)

    Kumar, Vipin; Delovitch, Terry L

    2014-01-01

    Natural killer T cells (NKT) can regulate innate and adaptive immune responses. Type I and type II NKT cell subsets recognize different lipid antigens presented by CD1d, an MHC class-I-like molecule. Most type I NKT cells express a semi-invariant T-cell receptor (TCR), but a major subset of type II NKT cells reactive to a self antigen sulphatide use an oligoclonal TCR. Whereas TCR-α dominates CD1d-lipid recognition by type I NKT cells, TCR-α and TCR-β contribute equally to CD1d-lipid recognition by type II NKT cells. These variable modes of NKT cell recognition of lipid–CD1d complexes activate a host of cytokine-dependent responses that can either exacerbate or protect from disease. Recent studies of chronic inflammatory and autoimmune diseases have led to a hypothesis that: (i) although type I NKT cells can promote pathogenic and regulatory responses, they are more frequently pathogenic, and (ii) type II NKT cells are predominantly inhibitory and protective from such responses and diseases. This review focuses on a further test of this hypothesis by the use of recently developed techniques, intravital imaging and mass cytometry, to analyse the molecular and cellular dynamics of type I and type II NKT cell antigen-presenting cell motility, interaction, activation and immunoregulation that promote immune responses leading to health versus disease outcomes. PMID:24428389

  8. Reciprocal complementation of the tumoricidal effects of radiation and natural killer cells.

    Directory of Open Access Journals (Sweden)

    Kai-Lin Yang

    Full Text Available The tumor microenvironment is a key determinant for radio-responsiveness. Immune cells play an important role in shaping tumor microenvironments; however, there is limited understanding of how natural killer (NK cells can enhance radiation effects. This study aimed to assess the mechanism of reciprocal complementation of radiation and NK cells on tumor killing. Various tumor cell lines were co-cultured with human primary NK cells or NK cell line (NK-92 for short periods and then exposed to irradiation. Cell proliferation, apoptosis and transwell assays were performed to assess apoptotic efficacy and cell viability. Western blot analysis and immunoprecipitation methods were used to determine XIAP (X-linked inhibitor of apoptosis protein and Smac (second mitochondria-derived activator of caspase expression and interaction in tumor cells. Co-culture did not induce apoptosis in tumor cells, but a time- and dose-dependent enhancing effect was found when co-cultured cells were irradiated. A key role for caspase activation via perforin/granzyme B (Grz B after cell-cell contact was determined, as the primary radiation enhancing effect. The efficacy of NK cell killing was attenuated by upregulation of XIAP to bind caspase-3 in tumor cells to escape apoptosis. Knockdown of XIAP effectively potentiated NK cell-mediated apoptosis. Radiation induced Smac released from mitochondria and neutralized XIAP and therefore increased the NK killing. Our findings suggest NK cells in tumor microenvironment have direct radiosensitization effect through Grz B injection while radiation enhances NK cytotoxicity through triggering Smac release.

  9. The application of natural killer (NK cell immunotherapy for the treatment of cancer

    Directory of Open Access Journals (Sweden)

    Rayne H Rouce

    2015-11-01

    Full Text Available Natural killer (NK cells are essential components of the innate immune system and play a critical role in host immunity against cancer. Recent progress in our understanding of NK cell immunobiology has paved the way for novel NK cell-based therapeutic strategies for the treatment of cancer. In this review, we will focus on recent advances in the field of NK cell immunotherapy, including augmentation of antibody-dependent cellular cytotoxicity, manipulation of receptor-mediated activation, and adoptive immunotherapy with ex vivo expanded, chimeric antigen receptor (CAR engineered or engager-modified NK cells. In contrast to T lymphocytes, donor NK cells do not attack non-hematopoietic tissues, suggesting that an NK-mediated anti-tumor effect can be achieved in the absence of graft-versus-host disease. Despite reports of clinical efficacy, a number of factors limit the application of NK cell immunotherapy for the treatment of cancer such as the failure of infused NK cells to expand and persist in vivo. Therefore efforts to enhance the therapeutic benefit of NK cell-based immunotherapy by developing strategies to manipulate the NK cell product, host factors and tumor targets are the subject of intense research. In the preclinical setting, genetic engineering of NK cells to express CARs to redirect their antitumor specificity has shown significant promise. Given the short lifespan and potent cytolytic function of mature NK cells, they are attractive candidate effector cells to express CARs for adoptive immunotherapies. Another innovative approach to redirect NK cytotoxicity towards tumor cells is to create either bispecific or trispecific antibodies, thus augmenting cytotoxicity against tumor-associated antigens. These are exciting times for the study of NK cells; with recent advances in the field of NK cell biology and translational research, it is likely that NK cell immunotherapy will move to the forefront of cancer immunotherapy over the next

  10. Physiology of natural killer cells. In vivo regulation of progenitors by interleukin 3

    International Nuclear Information System (INIS)

    Kalland, T.

    1987-01-01

    Adoptive transfer of bone marrow cells to syngeneic lethally irradiated C57BL/6 mice was used to study the maturation of natural killer (NK) cells from their progenitors. The NK progenitor cell was found to be asialomonoganglioside-negative, (aGM1-) Thy-1-, NK-1-, Ly-1-, Ly-2-, and L3T4-. The NK cells emerging from the bone marrow grafts were aGM1+, NK-1+, Thy-1+/-, Ly-1-, Ly-2-, and L3T4- and to have a target specter similar to that of NK cells isolated from the spleen of normal mice. The regulatory role of interleukin 2 (IL-2) and interleukin 3 (IL-3) for the maturation of NK cells was examined by exposure of the bone marrow cells to the lymphokines in vitro before bone marrow grafting or by treatment of bone marrow-grafted mice with lymphokines through s.c. implanted miniosmotic pumps. IL-3 antagonized the IL-2-induced maturation of NK cells in vitro and strongly inhibited the generation of NK cells after adoptive transfer of bone marrow cells in vivo. The suppressive effect of IL-3 was evident throughout the treatment period (8 or 16 days) but was apparently reversible because NK activity returned to control levels within 8 days after cessation of treatment. The inhibition of cytotoxic activity was accompanied by a reduced appearance of cells with the NK phenotypic markers aGM1 or NK-1, indicating that not only the cytotoxic activity of NK cells but also their actual formation was inhibited. Concomitantly, a moderate increase in cells expressing the T cell marker L3T4 and an increased proliferative response to the T cell mitogen concanavalin A was observed. A direct estimate of the effect of IL-3 on the frequency of NK cell progenitors was obtained by limiting dilution analysis of bone marrow cells at day 8 after bone marrow transplantation

  11. Arctigenin, a natural lignan compound, induces G0/G1 cell cycle arrest and apoptosis in human glioma cells

    OpenAIRE

    Maimaitili, Aisha; Shu, Zunhua; Cheng, Xiaojiang; Kaheerman, Kadeer; Sikandeer, Alifu; Li, Weimin

    2016-01-01

    The aim of the current study was to investigate the anticancer potential of arctigenin, a natural lignan compound, in malignant gliomas. The U87MG and T98G human glioma cell lines were treated with various concentrations of arctigenin for 48 h and the effects of arctigenin on the aggressive phenotypes of glioma cells were assessed. The results demonstrated that arctigenin dose-dependently inhibited the growth of U87MG and T98G cells, as determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphen...

  12. Endometrial aspiration biopsy: a non-invasive method of obtaining functional lymphoid progenitor cells and mature natural killer cells.

    LENUS (Irish Health Repository)

    McMenamin, Moya

    2012-09-01

    The aim of this study was to compare the efficacy of endometrial aspiration biopsy (EAB) with the more traditional dilatation and curettage (D&C) for the procurement of lymphoid progenitor cells and uterine natural killer (NK) populations in endometrial tissue. This prospective observational study conducted in a tertiary referral university hospital examined endometrium obtained from 32 women admitted for laparoscopic gynaecological procedures. Each participant had endometrium sampled using both EAB and D&C. Both methods were assessed as a source of uterine NK and lymphoid progenitor cells. Similar proportions of mature CD45+CD56+ NK cells (range 25.4-36.2%) and CD45+CD34+ lymphoid progenitors (range 1.2-2.0%) were found in tissue obtained using both EAB and D&C. These cells were adequate for flow cytometric analysis, magnetic bead separation and culture. Colony formation by the CD34+ population demonstrated maturational potential. Tissues obtained via endometrial biopsy and D&C are equivalent, by analysis of uterine NK and lymphoid progenitor cells. The aim of this study was to compare two methods of endometrial sampling - endometrial aspiration biopsy and traditional dilatation and curettage - for the procurement of haematopoietic stem cells and uterine natural killer (NK) populations in endometrial tissue. Thirty-two women who had gynaecological procedures in a tertiary referral hospital participated in this study and had endometrial tissue collected via both methods. Similar populations of mature NK cells and haematopoietic stem cells were found in tissue obtained using both endometrial aspiration biopsy and dilatation and curettage. Tissue obtained via endometrial aspiration biopsy was adequate for the culture and growth of haematopoietic stem cells. We conclude that tissue obtained via endometrial biopsy and dilatation and curettage is equivalent, by analysis of uterine NK and haematopoietic stem cells using flow cytometry. This has implications for further

  13. Large-scale isolation and cytotoxicity of extracellular vesicles derived from activated human natural killer cells.

    Science.gov (United States)

    Jong, Ambrose Y; Wu, Chun-Hua; Li, Jingbo; Sun, Jianping; Fabbri, Muller; Wayne, Alan S; Seeger, Robert C

    2017-01-01

    Extracellular vesicles (EVs) have been the focus of great interest, as they appear to be involved in numerous important cellular processes. They deliver bioactive macromolecules such as proteins, lipids, and nucleic acids, allowing intercellular communication in multicellular organisms. EVs are secreted by all cell types, including immune cells such as natural killer cells (NK), and they may play important roles in the immune system. Currently, a large-scale procedure to obtain functional NK EVs is lacking, limiting their use clinically. In this report, we present a simple, robust, and cost-effective method to isolate a large quantity of NK EVs. After propagating and activating NK cells ex vivo and then incubating them in exosome-free medium for 48 h, EVs were isolated using a polymer precipitation method. The isolated vesicles contain the tetraspanin CD63, an EV marker, and associated proteins (fibronectin), but are devoid of cytochrome C, a cytoplasmic marker. Nanoparticle tracking analysis showed a size distribution between 100 and 200 nm while transmission electron microscopy imaging displayed vesicles with an oval shape and comparable sizes, fulfilling the definition of EV. Importantly, isolated EV fractions were cytotoxic against cancer cells. Furthermore, our results demonstrate for the first time that isolated activated NK (aNK) cell EVs contain the cytotoxic proteins perforin, granulysin, and granzymes A and B, incorporated from the aNK cells. Activation of caspase -3, -7 and -9 was detected in cancer cells incubated with aNK EVs, and caspase inhibitors blocked aNK EV-induced cytotoxicity, suggesting that aNK EVs activate caspase pathways in target cells. The ability to isolate functional aNK EVs on a large scale may lead to new clinical applications. Abbreviations : NK: natural killer cells; activated NK (aNK) cells; EVs: extracellular vesicles; ALL: acute lymphoblastic leukaemia; aAPC: artificial antigen-presenting cell; TEM: transmission electron

  14. The correlation of lymphocyte subsets, natural killer cell, and Parkinson's disease: a meta-analysis.

    Science.gov (United States)

    Jiang, Sen; Gao, Hua; Luo, Qin; Wang, Pengfei; Yang, Xinling

    2017-08-01

    The correlation between immunity and Parkinson's disease was presented in many papers, which also discussed lymphocyte and natural killer cell. But these studies have yielded inconsistent results. To systematically review the relationship between the lymphocyte subsets/natural killer cell and the risk of Parkinson's disease, we electronically searched the SpringerLink, Web of Science, Ebsco-medline with full text, Pubmed, Elsevier-ScienceDirect, Ovid-lww-oup, Wanfang Data for case-control trials on comparing the number of peripheral blood lymphocyte subsets and natural killer cell in Parkinson's patients and healthy controls. According to the Cochrane methods, the reviewers selected literature, extracted data, and assessed the quality. Then, a meta-analysis was performed using RevMan 5.2. Finally, 21 case-control trials including 943 cases of Parkinson's disease were fit into our data analysis. Meta-analysis showed that the decreased numbers of CD3+, CD4+ lymphocyte subsets and the increased number of natural killer cell were found in Parkinson's disease patients. In the intermediate and late stage of PD, CD8+ lymphocyte subsets had a significant decrement. However, the number of B lymphocyte subsets had no significant association with Parkinson's disease. The lymphocyte subsets and NK cell may be associated with the risk of Parkinson's disease.

  15. Distribution of invariant natural killer T cells and dendritic cells in late pre-term birth without acute chorioamnionitis.

    Science.gov (United States)

    Negishi, Yasuyuki; Shima, Yoshio; Takeshita, Toshiyuki; Takahashi, Hidemi

    2017-06-01

    Acute chorioamnionitis (aCAM) is an important cause of pre-term birth. However, little is known about the pathogenesis of late pre-term birth without aCAM that was the most common category of pre-term birth. Here we analyze the kinetics of immune cells obtained from the decidua of women with late pre-term births with and without aCAM. Deciduas were obtained from women who underwent labor with late pre-term birth without aCAM (PB-n/aCAM) or with aCAM (PB-w/aCAM). The population of DEC-205 + dendritic cells (DCs), macrophages, invariant natural killer T (iNKT) cells, NK cells, CD8 + T cells, and CD4 + T cells were analyzed by flow cytometry. The number of iNKT cells was higher in the decidua obtained from women with PB-n/aCAM than PB-w/aCAM. DEC-205 + DCs obtained from women with PB-n/aCAM preferentially induced iNKT cell proliferation. iNKT cell accumulation with DEC-205 + DCs in PB-n/aCAM suggests that iNKT cells contribute to the onset of PB-n/aCAM. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Electrical characterization of dye sensitized nano solar cell using natural pomegranate juice as photosensitizer

    Science.gov (United States)

    Adithi, U.; Thomas, Sara; Uma, V.; Pradeep, N.

    2013-02-01

    This paper shows Electrical characterization of Dye Sensitized Solar Cell using natural dye, extracted from the pomegranate as a photo sensitizer and ZnO nanoparticles as semiconductor. The constituents of fabricated dye sensitized solar cell were working electrode, dye, electrolyte and counter electrode. ZnO nanoparticles were synthesized and used as semiconductor in working electrode. Carbon soot was used as counter electrode. The resistance of ZnO film on ITO film was found out. There was an increase in the resistance of the film and film changes from conducting to semiconducting. Photovoltaic parameters of the fabricated cell like Short circuit current, open circuit voltage, Fill factor and Efficiency were found out. This paper shows that usage of natural dyes like pomegranate juice as sensitizer enables faster and simpler production of cheaper and environmental friendly solar cell.

  17. Recent Advances in Cell Electrospining of Natural and Synthetic Nanofibers for Regenerative Medicine.

    Science.gov (United States)

    Zamani, Reza; Aval, Sedigheh Fekri; Pilehvar-Soltanahmadi, Younes; Nejati-Koshki, Kazem; Zarghami, Nosratollah

    2018-01-22

    The progression of nanotechnology provides opportunities to manipulate synthetic and natural materials to mimic the natural structure for tissue engineering applications. The electrospinning technique applies electrostatic principle to fabricate electrospun nanofibers. Nanofiber scaffolds are precisely similar to the native extracellular matrix (ECM) and support cell proliferation, adhesion, tendency to preserve their phenotypic shape and directed growth according to the nanofiber direction. This study reviewed both the natural and synthetic type of nanofibers and described the different properties used to trigger certain process in the tissue development. Also, the potential applications of electrospun scaffolds for regenerative medicine were summarized. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Outsider to insider: resetting the natural host niche of commensal E. coli K-12.

    Science.gov (United States)

    Sahu, Upasana; Kar, Sudeshna

    2012-01-01

    The status of E. coli K-12 as an exclusively non-invasive, non-pathogenic bacterium has almost been incontrovertible. Our recent finding that a mutation in one of its main architectural protein, HU, converts E. coli K-12 to an actively invasive form suggests that gaining host cell entry might be an expedient survival tactic for traditional commensals during certain altered host conditions. The mutant E. coli (SK3842) exhibits properties usually associated with pathogenic bacteria: host cell invasion, phagosomal disruption and intracellular replication. However, unlike the situation with some pathogens, internalized SK3842 imparts anti-apoptotic and cyto-protective effects rather than lethality on the host cell, both in vitro and in vivo. Here, we show that SK3842 also provides colonization resistance against other invasive pathogens--a trait not shared by the parental commensal strain. Thus, the altered lifestyle of SK3842 encompasses characteristics both from traditional pathogens as well as beneficial probiotic strains.

  19. The regulation of ovary and conceptus on the uterine natural killer cells during early pregnancy

    OpenAIRE

    Gong, Han; Chen, Yilu; Xu, Jingjie; Xie, Xingxing; Yu, Dainan; Yang, Bei; Kuang, Haibin

    2017-01-01

    Uterine natural killer (uNK) cells are short-lived, terminally differentiated and the most abundant lymphocytes in the uterus which play a crucial role in the spiral arteriole modification and establishment of successful pregnancy. Dysregulation of uNK cells has been linked to gestational implications such as recurrent pregnancy loss, preeclampsia and fetal growth retardation. There is evidence showing that progesterone and estrogen can regulate the recruitment, proliferation, differentiation...

  20. Influence of KIR gene copy number on natural killer cell education.

    Science.gov (United States)

    Béziat, Vivien; Traherne, James A; Liu, Lisa L; Jayaraman, Jyothi; Enqvist, Monika; Larsson, Stella; Trowsdale, John; Malmberg, Karl-Johan

    2013-06-06

    Natural killer (NK) cells are functionally tuned by education via killer cell immunoglobulin receptors (KIRs) interacting with HLA class I molecules. We examined the effect of KIR gene copy number variation on the education of human NK cells. The frequency of NK cells expressing a given KIR correlated with the copy number of that gene. However, coexpression of multiple copies from a single locus, or duplicated loci, was infrequent, which is in line with independent transcriptional regulation of each allele or copy. Intriguingly, coexpression of 2 KIR alleles, resulting in higher surface expression, did not lead to enhanced functional responses in vitro or to selective advantages during in vivo responses to cytomegalovirus infection, suggesting that receptor density does not influence NK education at the single cell level. However, individuals with multiple KIR gene copies had higher frequencies of responding cells, consistent with heightened overall responsiveness.

  1. A Novel Natural Product, KL-21, Inhibits Proliferation and Induces Apoptosis in Chronic Lymphocytic Leukemia Cells

    Directory of Open Access Journals (Sweden)

    Aysun Adan Gökbulut

    2015-06-01

    Full Text Available INTRODUCTION: The aims of this study were to examine the cytotoxic and apoptotic effects of KL-21, a novel plant product (produced by Naturin Natural Products, İzmir, Turkey, on 232B4 chronic lymphocytic leukemia (CLL cells and to determine the cytotoxic effects on healthy BEAS-2B human bronchial epithelial cells. METHODS: The cytotoxic effect of KL-21 was determined by MTT cell proliferation assay. Changes in caspase-3 enzyme activity were measured using the caspase-3 colorimetric assay. Changes in mitochondrial membrane potential were determined using the JC-1 dye-based method. Annexin V-FITC/PI double staining was performed to measure the apoptotic cell population. Effects of KL-21 on cell cycle profiles of CLL cells were investigated by flow cytometry. RESULTS: We detected time- and concentration-dependent increases in the cytotoxic effect of KL-21 on 232B4 CLL cells. However, we also showed that, especially at higher concentrations, KL-21 was less cytotoxic towards BEAS-2B healthy cells than towards CLL cells. Annexin-V/PI double staining results showed that the apoptotic cell population increased in 232B4 cells. Increasing concentrations of KL-21 increased caspase-3 enzyme activity and induced loss of mitochondrial membrane potential. KL-21 administration resulted in small increases in the percentage of the cells in the G0/G1 phase while it decreased the S phase cell population up to 1 mg/mL. At the highest concentration, most of the cells accumulated in the G0/G1 phase. DISCUSSION AND CONCLUSION: KL-21 has a growth-inhibitory effect on 232B4 CLL cells. KL-21 causes apoptosis and cell cycle arrest at G0/G1.

  2. Human natural killer cells: news in the therapy of solid tumors and high-risk leukemias.

    Science.gov (United States)

    Pietra, Gabriella; Vitale, Chiara; Pende, Daniela; Bertaina, Alice; Moretta, Francesca; Falco, Michela; Vacca, Paola; Montaldo, Elisa; Cantoni, Claudia; Mingari, Maria Cristina; Moretta, Alessandro; Locatelli, Franco; Moretta, Lorenzo

    2016-04-01

    It is well established that natural killer (NK) cells play an important role in the immunity against cancer, while the involvement of other recently identified, NK-related innate lymphoid cells is still poorly defined. In the haploidentical hematopoietic stem cell transplantation for the therapy of high-risk leukemias, NK cells have been shown to exert a key role in killing leukemic blasts residual after conditioning. While the clinical results in the cure of leukemias are excellent, the exploitation of NK cells in the therapy of solid tumors is still limited and unsatisfactory. In solid tumors, NK cell function may be inhibited via different mechanisms, occurring primarily at the tumor site. The cellular interactions in the tumor microenvironment involve tumor cells, stromal cells and resident or recruited leukocytes and may favor tumor evasion from the host's defenses. In this context, a number of cytokines, growth factors and enzymes synthesized by tumor cells, stromal cells, suppressive/regulatory myeloid and lymphoid cells may substantially impair the function of different tumor-reactive effector cells, including NK cells. The identification and characterization of such mechanisms may offer clues for the development of new immunotherapeutic strategies to restore effective anti-tumor responses. In order to harness NK cell-based immunotherapies, several approaches have been proposed, including reinforcement of NK cell cytotoxicity by means of specific cytokines, antibodies or drugs. These new tools may improve NK cell function and/or increase tumor susceptibility to NK-mediated killing. Hence, the integration of NK-based immunotherapies with conventional anti-tumor therapies may increase chances of successful cancer treatment.

  3. Prior lactose glycation of caseinate via the Maillard reaction affects in vitro activities of the pepsin-trypsin digest toward intestinal epithelial cells.

    Science.gov (United States)

    Wang, X P; Zhao, X H

    2017-07-01

    The well-known Maillard reaction in milk occurs between lactose and milk proteins during thermal treatment, and its effects on milk nutrition and safety have been well studied. A lactose-glycated caseinate was prepared via this reaction and digested using 2 digestive proteases, pepsin and trypsin. The glycated caseinate digest was assessed for its in vitro activities on rat intestinal epithelial cells in terms of growth proliferation, anti-apoptotic effect, and differentiation induction using caseinate digest as reference, to verify potential effects of the Maillard reaction on these activities of caseinate digest to the cells. Two digests had proliferative and anti-apoptotic effects, and reached the highest effects at 0.02 g/L of digest concentration with treatment time of 24 h. In comparison with caseinate digest, glycated caseinate digest always showed weaker proliferative (5.3-14.2%) and anti-apoptotic (5.9-39.0%) effects, and was more toxic to the cells at 0.5 g/L of digest concentration with treatment time of 48 h. However, glycated caseinate digest at 2 incubation times of 4 to 7 d showed differentiation induction higher than caseinate digest, as it could confer the cells with increased activities in lactase (16.3-26.6%), sucrase (22.4-31.2%), and alkaline phosphatase (17.4-24.8%). Transmission electron microscopy observation results also confirmed higher differentiation induction of glycated caseinate digest. Amino acid loss and lactose glycation partially contributed to these decreased and enhanced activities of glycated caseinate digest, respectively. The Maillard reaction of caseinate and lactose is thus shown in this study to have effects on the activities of caseinate digest to intestinal epithelial cells. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  4. Acquired Natural Killer Cell Dysfunction in the Tumor Microenvironment of Classic Hodgkin Lymphoma

    Directory of Open Access Journals (Sweden)

    Jodi Chiu

    2018-02-01

    Full Text Available An understanding of interactions within the tumor microenvironment (TME of classic Hodgkin lymphoma (cHL has helped pave the way to novel immunotherapies that have enabled dormant and tumor-tolerant immune cells to be reactivated. The immunosuppressive nature of the TME in cHL specifically inhibits the proliferation and activity of natural killer (NK cells, which contributes to tumor immune-escape mechanisms. This deficiency of NK cells begins at the tumor site and progresses systemically in patients with advanced disease or adverse prognostic factors. Several facets of cHL account for this effect on NK cells. Locally, malignant Reed–Sternberg cells and cells from the TME express ligands for inhibitory receptors on NK cells, including HLA-E, HLA-G, and programmed death-ligand 1. The secretion of chemokines and cytokines, including soluble IL-2 receptor (sCD25, Transforming Growth Factor-β, IL-10, CXCL9, and CXCL10, mediates the systemic immunosuppression. This review also discusses the potential reversibility of quantitative and functional NK cell deficiencies in cHL that are likely to lead to novel treatments.

  5. Studies of baby hamster kidney natural cell aggregation in suspended batch cultures.

    Science.gov (United States)

    Moreira, J L; Alves, P M; Rodrigues, J M; Cruz, P E; Aunins, J G; Carrondo, M J

    1994-11-30

    Microcarrier cultures of animal cells of industrial relevance are known to shed aggregates into the suspension phase. For a BHK cell line, which is known to be prone to aggregate naturally, microcarrier and aggregate forms of culture are compared in spinner culture. In microcarrier cultures, it is shown that increasing initial microcarrier concentration yields decreasing concentration of smaller aggregates in suspension; roughly equivalent concentrations of total cells and single cells in suspension are obtained. In the absence of Cytodex 3, aggregate final size is hydrodynamically controlled in batch and semicontinuous suspension culture. Rate of agitation is the main variable controlling aggregate size in batch cultures. The range of agitation rates studied (20 to 70 rpm in 250 mL spinner flasks) produced aggregates with maximum sizes of 200 microns. Necrotic centers were not observed; this was confirmed by Trypan blue viability measurements after mechanical dissociation of aggregates and also by the constant productivity obtained from different aggregate sizes. Comparing aggregate and microcarrier culture conditions, it is shown that at 100 rpm maximum total cell concentration is larger in the absence of microcarriers; dead cell concentrations, most of which exist in suspension, are slightly larger in microcarrier culture. Total viable cell concentrations in aggregate, hydrodynamically controlled culture, are almost one order of magnitude higher than in microcarrier cultures. These results suggest that there might be advantages in using aggregate cultures under hydrodynamic control of aggregate size in lieu of microcarrier cultures for naturally aggregating cell lines.

  6. Cell size dependent toxicity thresholds of polycyclic aromatic hydrocarbons to natural and cultured phytoplankton populations

    Energy Technology Data Exchange (ETDEWEB)

    Echeveste, Pedro, E-mail: pedro.echeveste@uib.e [Department of Global Change Research, IMEDEA (CSIC-UIB) Instituto Mediterraneo de Estudios Avanzados, Miquel Marques 21, 07190 Esporles (Spain); Agusti, Susana, E-mail: sagusti@uib.e [Department of Global Change Research, IMEDEA (CSIC-UIB) Instituto Mediterraneo de Estudios Avanzados, Miquel Marques 21, 07190 Esporles (Spain); Dachs, Jordi, E-mail: jdmqam@cid.csic.e [Department of Environmental Chemistry, Institute of Environmental Assessment and Water Studies (IDAEA-CSIC), Jordi Girona Salgado 18, 08034 Barcelona (Spain)

    2010-01-15

    The toxicity of pyrene and phenanthrene to phytoplankton was studied by analyzing the effect on the growth, abundance and cell viability of cultured species and natural communities of the Atlantic Ocean and the Mediterranean Sea. A decrease in cell abundance, and growth rate was observed as concentration of PAHs increased, with catastrophic cell mortality induced at the highest PAH concentration tested. A strong positive linear relationship was observed between the LC50 (the PAH concentration at which cell population will decline by a half), and the species cell volume, for both phenanthrene and pyrene. Natural communities were however significantly more sensitive to PAHs than cultured phytoplankton, as indicated by the lower slope (e.g. 0.23 and 0.65, respectively, for pyrene) of the relationship LC50 vs. cell volume. The results highlight the importance of cell size in determining the phytoplankton sensitivity to PAHs identifying the communities from the oligotrophic ocean to be more vulnerable. - Cell size is the major factor determining phytoplankton sensitivity to PAHs.

  7. Globular Adiponectin Inhibits the Apoptosis of Mesenchymal Stem Cells Induced by Hypoxia and Serum Deprivation via the AdipoR1-Mediated Pathway

    OpenAIRE

    Xia-Qiu Tian; Yue-Jin Yang; Qing Li; Pei-Sen Huang; Xiang-Dong Li; Chen Jin; Kang Qi; Lei-Pei Jiang; Gui-Hao Chen

    2016-01-01

    Background/Aims: Poor viability of transplanted mesenchymal stem cells (MSCs) within the ischemic heart limits their therapeutic potential for cardiac repair. Globular adiponectin (gAPN) exerts anti-apoptotic effects on several types of stem cells. Herein, we investigated the effect of gAPN on the MSCs against apoptosis induced by hypoxia and serum deprivation (H/SD). Methods: MSCs exposed to H/SD conditions were treated with different concentrations of gAPN. To identify the main type of rece...

  8. Berberine, a natural antidiabetes drug, attenuates glucose neurotoxicity and promotes Nrf2-related neurite outgrowth

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Ya-Yun [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Tseng, Yu-Ting [Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Lo, Yi-Ching, E-mail: yichlo@kmu.edu.tw [Department of Pharmacology, School of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Medicine, College of Medicine, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Graduate Institute of Natural Products, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China)

    2013-11-01

    Reactive oxygen intermediates production and apoptotic damage induced by high glucose are major causes of neuronal damage in diabetic neuropathy. Berberine (BBR), a natural antidiabetes drug with PI3K-activating activity, holds promise for diabetes because of its dual antioxidant and anti-apoptotic activities. We have previously reported that BBR attenuated H{sub 2}O{sub 2} neurotoxicity via activating the PI3K/Akt/Nrf2-dependent pathway. In this study, we further explored the novel protective mechanism of BBR on high glucose-induced apoptotic death and neurite damage of SH-SY5Y cells. Results indicated BBR (0.1–10 nM) significantly attenuated reactive oxygen species (ROS) production, nucleus condensation, and apoptotic death in high glucose-treated cells. However, AG1024, an inhibitor of insulin growth factor-1 (IGF-1) receptor, significantly abolished BBR protection against high glucose-induced neuronal death. BBR also increased Bcl-2 expression and decreased cytochrome c release. High glucose down-regulated IGF-1 receptor and phosphorylation of Akt and GSK-3β, the effects of which were attenuated by BBR treatment. BBR also activated nuclear erythroid 2-related factor 2 (Nrf2), the key antioxidative transcription factor, which is accompanied with up-regulation of hemeoxygenase-1 (HO-1). Furthermore, BBR markedly enhanced nerve growth factor (NGF) expression and promoted neurite outgrowth in high glucose-treated cells. To further determine the role of the Nrf2 in BBR neuroprotection, RNA interference directed against Nrf2 was used. Results indicated Nrf2 siRNA abolished BBR-induced HO-1, NGF, neurite outgrowth and ROS decrease. In conclusion, BBR attenuated high glucose-induced neurotoxicity, and we are the first to reveal this novel mechanism of BBR as an Nrf2 activator against glucose neurotoxicity, providing another potential therapeutic use of BBR on the treatment of diabetic complications. - Highlights: • BBR attenuates high glucose-induced ROS

  9. The Immunomodulatory Small Molecule Imiquimod Induces Apoptosis in Devil Facial Tumour Cell Lines.

    Directory of Open Access Journals (Sweden)

    Amanda L Patchett

    Full Text Available The survival of the Tasmanian devil (Sarcophilus harrisii is threatened by devil facial tumour disease (DFTD. This transmissible cancer is usually fatal, and no successful treatments have been developed. In human studies, the small immunomodulatory molecule imiquimod is a successful immunotherapy, activating anti-tumour immunity via stimulation of toll-like receptor-7 (TLR7 signaling pathways. In addition, imiquimod is a potent inducer of apoptosis in human tumour cell lines via TLR7 independent mechanisms. Here we investigate the potential of imiquimod as a DFTD therapy through analysis of treated DFTD cell lines and Tasmanian devil fibroblasts. WST-8 proliferation assays and annexin V apoptosis assays were performed to monitor apoptosis, and changes to the expression of pro- and anti-apoptotic genes were analysed using qRT-PCR. Our results show that DFTD cell lines, but not Tasmanian devil fibroblasts, are sensitive to imiquimod-induced apoptosis in a time and concentration dependent manner. Induction of apoptosis was accompanied by down-regulation of the anti-apoptotic BCL2 and BCLXL genes, and up-regulation of the pro-apoptotic BIM gene. Continuous imiquimod treatment was required for these effects to occur. These results demonstrate that imiquimod can deregulate DFTD cell growth and survival in direct and targeted manner. In vivo, this may increase DFTD vulnerability to imiquimod-induced TLR7-mediated immune responses. Our findings have improved the current knowledge of imiquimod action in tumour cells for application to both DFTD and human cancer therapy.

  10. The role of natural killer T cells in dendritic cell licensing, cross-priming and memory CD8+ T cell generation

    Directory of Open Access Journals (Sweden)

    Catherine eGottschalk

    2015-07-01

    Full Text Available New vaccination strategies focus on achieving CD8+ T cell (CTL immunity rather than on induction of protective antibody responses. While the requirement of CD4+ T (Th cell help in dendritic cell (DC activation and licensing, and in CTL memory induction has been described in several disease models, CTL responses may occur in a Th cell help independent manner. Natural Killer T cells (NKT cells can substitute for Th cell help and license DC as well. NKT cells produce a broad spectrum of Th1 and Th2 cytokines, thereby inducing a similar set of costimulatory molecules and cytokines in DC. This form of licensing differs from Th cell help by inducing other chemokines: while Th cell licensed DC produce CCR5 ligands, NKT cell-licensed DC produce CCL17 which attracts CCR4+ CD8+ T cells for subsequent activation. It has recently been shown that iNKT cells do not only enhance immune responses against bacterial pathogens or parasites, but also play a role in viral infections. The inclusion of NKT cell ligands in Influenza virus vaccines enhanced memory CTL generation and protective immunity in a mouse model. This review will focus on the role of iNKT cells in the cross-talk with cross-priming DC and memory CD8+ T cell formation.

  11. Natural compounds' activity against cancer stem-like or fast-cycling melanoma cells.

    Directory of Open Access Journals (Sweden)

    Malgorzata Sztiller-Sikorska

    Full Text Available BACKGROUND: Accumulating evidence supports the concept that melanoma is highly heterogeneous and sustained by a small subpopulation of melanoma stem-like cells. Those cells are considered as responsible for tumor resistance to therapies. Moreover, melanoma cells are characterized by their high phenotypic plasticity. Consequently, both melanoma stem-like cells and their more differentiated progeny must be eradicated to achieve durable cure. By reevaluating compounds in heterogeneous melanoma populations, it might be possible to select compounds with activity not only against fast-cycling cells but also against cancer stem-like cells. Natural compounds were the focus of the present study. METHODS: We analyzed 120 compounds from The Natural Products Set II to identify compounds active against melanoma populations grown in an anchorage-independent manner and enriched with cells exerting self-renewing capacity. Cell viability, cell cycle arrest, apoptosis, gene expression, clonogenic survival and label-retention were analyzed. FINDINGS: Several compounds efficiently eradicated cells with clonogenic capacity and nanaomycin A, streptonigrin and toyocamycin were effective at 0.1 µM. Other anti-clonogenic but not highly cytotoxic compounds such as bryostatin 1, siomycin A, illudin M, michellamine B and pentoxifylline markedly reduced the frequency of ABCB5 (ATP-binding cassette, sub-family B, member 5-positive cells. On the contrary, treatment with maytansine and colchicine selected for cells expressing this transporter. Maytansine, streptonigrin, toyocamycin and colchicine, even if highly cytotoxic, left a small subpopulation of slow-dividing cells unaffected. Compounds selected in the present study differentially altered the expression of melanocyte/melanoma specific microphthalmia-associated transcription factor (MITF and proto-oncogene c-MYC. CONCLUSION: Selected anti-clonogenic compounds might be further investigated as potential adjuvants

  12. Bee venom protects SH-SY5Y human neuroblastoma cells from 1-methyl-4-phenylpyridinium-induced apoptotic cell death.

    Science.gov (United States)

    Doo, Ah-Reum; Kim, Seung-Nam; Kim, Seung-Tae; Park, Ji-Yeun; Chung, Sung-Hyun; Choe, Bo-Young; Chae, Younbyoung; Lee, Hyejung; Yin, Chang-Shik; Park, Hi-Joon

    2012-01-06

    Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by progressive selective loss of dopaminergic neurons in the substantia nigra. Recently, bee venom was reported to protect dopaminergic neurons in the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine induced mice PD model, however, the underlying mechanism is not fully understood. The objective of the present study is to investigate the neuroprotective mechanism of bee venom against Parkinsonian toxin, 1-methyl-4-phenylpyridine (MPP(+)), in SH-SY5Y human neuroblastoma cells. Our results revealed that bee venom pretreatment (1-100 ng/ml) increased the cell viability and decreased apoptosis assessed by DNA fragmentation and caspase-3 activity assays in MPP(+)-induced cytotoxicity in SH-SY5Y cells. Bee venom increased the anti-apoptotic Bcl-2 expression and decreased the pro-apoptotic Bax, cleaved PARP expressions. In addition, bee venom prevented the MPP(+)-induced suppression of Akt phosphorylation, and the neuroprotective effect of bee venom against MPP(+)-induced cytotoxicity was inhibited by a phosphatidylinositol 3-kinase (PI3K) inhibitor, LY294002. These results suggest that the anti-apoptotic effect of bee venom is mediated by the cell survival signaling, the PI3K/Akt pathway. These results provide new evidence for elucidating the mechanism of neuroprotection of bee venom against PD. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. Mixed Signals: Co-Stimulation in Invariant Natural Killer T Cell-Mediated Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Susannah C. Shissler

    2017-11-01

    Full Text Available Invariant natural killer T (iNKT cells are an integral component of the immune system and play an important role in antitumor immunity. Upon activation, iNKT cells can directly kill malignant cells as well as rapidly produce cytokines that stimulate other immune cells, making them a front line defense against tumorigenesis. Unfortunately, iNKT cell number and activity are reduced in multiple cancer types. This anergy is often associated with upregulation of co-inhibitory markers such as programmed death-1. Similar to conventional T cells, iNKT cells are influenced by the conditions of their activation. Conventional T cells receive signals through the following three types of receptors: (1 T cell receptor (TCR, (2 co-stimulation molecules, and (3 cytokine receptors. Unlike conventional T cells, which recognize peptide antigen presented by MHC class I or II, the TCRs of iNKT cells recognize lipid antigen in the context of the antigen presentation molecule CD1d (Signal 1. Co-stimulatory molecules can positively and negatively influence iNKT cell activation and function and skew the immune response (Signal 2. This study will review the background of iNKT cells and their co-stimulatory requirements for general function and in antitumor immunity. We will explore the impact of monoclonal antibody administration for both blocking inhibitory pathways and engaging stimulatory pathways on iNKT cell-mediated antitumor immunity. This review will highlight the incorporation of co-stimulatory molecules in antitumor dendritic cell vaccine strategies. The use of co-stimulatory intracellular signaling domains in chimeric antigen receptor-iNKT therapy will be assessed. Finally, we will explore the influence of innate-like receptors and modification of immunosuppressive cytokines (Signal 3 on cancer immunotherapy.

  14. Naturally occurring and stress induced tubular structures from mammalian cells, a survival mechanism

    Directory of Open Access Journals (Sweden)

    He Jian

    2007-08-01

    to stress conditions, like dehydration. The disintegrative, mobile, disruptive and ubiquitous nature of straw cells makes this a possible physiological process that may be involved in human health, longevity, and various types of diseases such as cancer.

  15. NK-cell-dependent killing of colon carcinoma cells is mediated by natural cytotoxicity receptors (NCRs) and stimulated by parvovirus infection of target cells

    International Nuclear Information System (INIS)

    Bhat, Rauf; Rommelaere, Jean

    2013-01-01

    Investigating how the immune system functions during malignancies is crucial to developing novel therapeutic strategies. Natural killer (NK) cells, an important component of the innate immune system, play a vital role in immune defense against tumors and virus-infected cells. The poor survival rate in colon cancer makes it particularly important to develop novel therapeutic strategies. Oncolytic viruses, in addition to lysing tumor cells, may have the potential to augment antitumor immune responses. In the present study, we investigate the role of NK cells and how parvovirus H-1PV can modulate NK-cell mediated immune responses against colon carcinoma. Human NK cells were isolated from the blood of healthy donors. The cytotoxicity and antibody-mediated inhibition of NK cells were measured in chromium release assays. Phenotypic assessment of colon cancer and dendritic cells was done by FACS. The statistical significance of the results was calculated with Student’s t test (*p <0.05; **, p < 0.01; ***, p < 0.001). We show that IL-2-activated human NK cells can effectively kill colon carcinoma cells. Killing of colon carcinoma cells by NK cells was further enhanced upon infection of the former cells with parvovirus H-1PV. H-1PV has potent oncolytic activity against various tumors, yet its direct killing effect on colon carcinoma cells is limited. The cytotoxicity of NK cells towards colon carcinoma cells, both mock- and H-1PV-infected, was found to be mostly mediated by a combination of natural cytotoxicity receptors (NCRs), namely NKp30, 44, and 46. Colon carcinoma cells displayed low to moderate expression of NK cell ligands, and this expression was modulated upon H-1PV infection. Lysates of H-1PV-infected colon carcinoma cells were found to increase MHC class II expression on dendritic cells. Altogether, these data suggest that IL-2-activated NK cells actively kill colon carcinoma cells and that this killing is mediated by several natural cytotoxicity receptors

  16. Endometrial natural killer (NK) cells reveal a tissue-specific receptor repertoire.

    Science.gov (United States)

    Feyaerts, D; Kuret, T; van Cranenbroek, B; van der Zeeuw-Hingrez, S; van der Heijden, O W H; van der Meer, A; Joosten, I; van der Molen, R G

    2018-02-13

    Is the natural killer (NK) cell receptor repertoire of endometrial NK (eNK) cells tissue-specific? The NK cell receptor (NKR) expression profile in pre-pregnancy endometrium appears to have a unique tissue-specific phenotype, different from that found in NK cells in peripheral blood, suggesting that these cells are finely tuned towards the reception of an allogeneic fetus. NK cells are important for successful pregnancy. After implantation, NK cells encounter extravillous trophoblast cells and regulate trophoblast invasion. NK cell activity is amongst others regulated by C-type lectin heterodimer (CD94/NKG2) and killer cell immunoglobulin-like (KIR) receptors. KIR expression on decidual NK cells is affected by the presence of maternal HLA-C and biased towards KIR2D expression. However, little is known about NKR expression on eNK cells prior to pregnancy. In this study, matched peripheral and menstrual blood (a source of endometrial cells) was obtained from 25 healthy females with regular menstrual cycles. Menstrual blood was collected during the first 36 h of menstruation using a menstrual cup, a non-invasive technique to obtain endometrial cells. KIR and NKG2 receptor expression on eNK cells was characterized by 10-color flow cytometry, and compared to matched pbNK cells of the same female. KIR and HLA-C genotypes were determined by PCR-SSOP techniques. Anti-CMV IgG antibodies in plasma were measured by chemiluminescence immunoassay. KIR expression patterns of eNK cells collected from the same female do not differ over consecutive menstrual cycles. The percentage of NK cells expressing KIR2DL2/L3/S2, KIR2DL3, KIR2DL1, LILRB1 and/or NKG2A was significantly higher in eNK cells compared to pbNK cells, while no significant difference was observed for NKG2C, KIR2DL1/S1, and KIR3DL1. The NKR repertoire of eNK cells was clearly different from pbNK cells, with eNK cells co-expressing more than three NKR simultaneously. In addition, outlier analysis revealed 8 and 15 NKR

  17. Anticancer and antimetastatic activities of Renieramycin M, a marine tetrahydroisoquinoline alkaloid, in human non-small cell lung cancer cells.

    Science.gov (United States)

    Halim, Hasseri; Chunhacha, Preedakorn; Suwanborirux, Khanit; Chanvorachote, Pithi

    2011-01-01

    Renieramycin M, has been shown to exhibit promising anticancer activity against some cancer cell lines; however, the underlying mechanism remains unknown. Renieramycin M was isolated from the blue sponge Xestospongia sp. Anticancer and antimetastatic activities of renieramycin M were investigated in human non-small cell lung cancer cells. Renieramycin M treatment caused p53 activation, which subsequently down-regulated anti-apoptotic MCL-1 and BCL-2 proteins, while the level of pro-apoptotic BAX protein was not altered. The subtoxic concentrations of renieramycin M significantly decreased invasion and migration abilities of cancer cells. In addition, this compound showed a strong inhibitory effect on anchorage-independent growth of the cells. These results reveal that renieramycin M induced lung cancer cells apoptosis through p53-dependent pathway and the compound may inhibit progression and metastasis of lung cancer cells.

  18. Increase in natural killer cell activity during diethylcarbamazine treatment of patients with filariasis

    DEFF Research Database (Denmark)

    Pedersen, B K; Bygbjerg, Ib Christian; Svenson, M

    1987-01-01

    that of the controls remained unchanged. We conclude that the augmentation of baseline NK cell activity, as well as interferon- and interleukin-2-enhanced NK cell activity seen in the patients, is not a direct effect of DEC, but is related to the reaction to DEC in lymphatic filariasis and onchocerciasis.......Two patients, one with Bancroftian filariasis and the other with onchocerciasis, and two healthy controls were treated with diethylcarbamazine (DEC). The natural killer (NK) cell activity of the two patients increased during DEC treatment to 2.5 and 2.8 times, respectively, while...

  19. Natural Killer Cell Education and the Response to Infection and Cancer Therapy: Stay Tuned.

    Science.gov (United States)

    Boudreau, Jeanette E; Hsu, Katharine C

    2018-03-01

    The functional capacities of natural killer (NK) cells differ within and between individuals, reflecting considerable genetic variation. 'Licensing/arming', 'disarming', and 'tuning' are models that have been proposed to explain how interactions between MHC class I molecules and their cognate inhibitory receptors - Ly49 in mice and KIR in humans - 'educate' NK cells for variable reactivity and sensitivity to inhibition. In this review we discuss recent progress toward understanding the genetic, epigenetic, and molecular features that titrate NK effector function and inhibition, and the impact of variable NK cell education on human health and disease. Copyright © 2018 Elsevier Ltd. All rights reserved.

  20. Effect of ranitidine on postoperative suppression of natural killer cell activity and delayed hypersensitivity

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen; Pedersen, B K; Moesgaard, F

    1989-01-01

    hypersensitivity (DTH) antigens, and blood drawn immediately before and 24 hours after skin incision was analyzed for spontaneous and in vitro stimulated (IL-2, IFN-alpha or indomethacin) natural killer (NK) cell activity and PHA and PPD-stimulated lymphocyte proliferation. Lymphocyte subsets (helper...

  1. Primary extranodal Natural Killer/ T-cell lymphoma of the ethmoid sinus masquerading as orbital cellulitis

    Directory of Open Access Journals (Sweden)

    Ivana Mahovne

    2009-08-01

    Full Text Available This report presents a case of an exceptionallyrare primary Natural Killer/T cell (NK/T lymphomaof the right paranasal frontal and ethmoidsinuses in a patient treated previously for rightside chronic sinusitis. It highlighted the importanceof adequate tissue biopsy and patohistologicalexamination in patients with chronic sinusitisor orbital cellulitis that fail to respond totraditional management.

  2. Role of Natural Killer T Cells In Immunogenic Chemotherapy for Breast Cancer

    Science.gov (United States)

    2012-09-01

    Galactosylceramide (a-GalCer) is a marine sponge -derived glycolipid Ag (1) that binds CD1d, a MHCclass I-like molecule, expressed by APCs to specifi- cally...Y. Kinjo, and M. Kronenberg. 2007. The unique role of natural killer T cells in the response to microorganisms . Nat. Rev. Microbiol. 5: 405– 417. 45

  3. DNA DAMAGE REPAIR AND CELL CYCLE CONTROL: A NATURAL BIO-DEFENSE MECHANISM

    Science.gov (United States)

    DNA DAMAGE REPAIR AND CELL CYCLE CONTROL: A natural bio-defense mechanismAnuradha Mudipalli.Maintenance of genetic information, including the correct sequence of nucleotides in DNA, is essential for replication, gene expression, and protein synthesis. DNA lesions onto...

  4. Mass spectrometric analysis of the glycosphingolipid-enriched microdomains of rat natural killer cells

    Czech Academy of Sciences Publication Activity Database

    Man, Petr; Novák, Petr; Cebecauer, M.; Horváth, Ondřej; Fišerová, Anna; Havlíček, Vladimír; Bezouška, Karel

    2005-01-01

    Roč. 5, - (2005), s. 113-122 ISSN 1615-9853 R&D Projects: GA ČR GV312/98/K034 Institutional research plan: CEZ:AV0Z5020903 Keywords : activation receptor * mebrane microdomains * natural killer cells Subject RIV: EE - Microbiology, Virology Impact factor: 6.088, year: 2005

  5. Type II Natural Killer T (NKT) Cells And Their Emerging Role In Health And Disease

    Science.gov (United States)

    Dhodapkar, Madhav V.; Kumar, Vipin

    2016-01-01

    Natural killer T (NKT) cells recognize lipid antigens presented by a class I MHC-like molecule CD1d, a member of the CD1 family. While most of the initial studies on NKT cells focused on a subset with semi-invariant T cell receptor (TCR) termed iNKT cells, majority of CD1d-restricted lipid-reactive human T cells express diverse TCRs and are termed as type II NKT cells. These cells constitute a distinct population of circulating and tissue-resident effector T cells with immune-regulatory properties. They react to a growing list of self- as well as non-self lipid ligands, and share some properties with both iNKT as well as conventional T cells. Emerging body of evidence points to their role in the regulation of immunity to pathogens/tumors and in autoimmune/metabolic disorders. Improved understanding of the biology of these cells and the ability to manipulate their function may be of therapeutic benefit in diverse disease conditions. PMID:28115591

  6. Natural Killer Cell-Based Cancer Immunotherapies: From Immune Evasion to Promising Targeted Cellular Therapies

    Directory of Open Access Journals (Sweden)

    Erhard Hofer

    2017-07-01

    Full Text Available Immunotherapies based on natural killer (NK cells are among the most promising therapies under development for the treatment of so far incurable forms of leukemia and other types of cancer. The importance of NK cells for the control of viral infections and cancer is supported among others by the findings that viruses and tumors use a multitude of mechanisms to subvert and evade the NK cell system. Infections and malignant diseases can further lead to the shaping of NK cell populations with altered reactivity. Counter measures of potential therapeutic impact include the blocking of inhibitory interactions between NK cell receptors and their cellular ligands, the enhancement of activating receptor signals, and the infusion of large numbers of ex vivo generated and selected NK cells. Moreover, the specific cross-linking of NK cells to their target cells using chimeric antigen receptors or therapeutic bi-/trispecific antibody reagents is a promising approach. In this context, NK cells stand out by their positive effects and safety demonstrated in most clinical trials so far. Based in part on results of the recent EC-sponsored project “NATURIMMUN” and considering additional published work in the field, we discuss below new developments and future directions that have the potential to further advance and establish NK cell-based therapies at the clinics on a broader scale.

  7. Natural Killer Cell-Based Cancer Immunotherapies: From Immune Evasion to Promising Targeted Cellular Therapies.

    Science.gov (United States)

    Hofer, Erhard; Koehl, Ulrike

    2017-01-01

    Immunotherapies based on natural killer (NK) cells are among the most promising therapies under development for the treatment of so far incurable forms of leukemia and other types of cancer. The importance of NK cells for the control of viral infections and cancer is supported among others by the findings that viruses and tumors use a multitude of mechanisms to subvert and evade the NK cell system. Infections and malignant diseases can further lead to the shaping of NK cell populations with altered reactivity. Counter measures of potential therapeutic impact include the blocking of inhibitory interactions between NK cell receptors and their cellular ligands, the enhancement of activating receptor signals, and the infusion of large numbers of ex vivo generated and selected NK cells. Moreover, the specific cross-linking of NK cells to their target cells using chimeric antigen receptors or therapeutic bi-/trispecific antibody reagents is a promising approach. In this context, NK cells stand out by their positive effects and safety demonstrated in most clinical trials so far. Based in part on results of the recent EC-sponsored project "NATURIMMUN" and considering additional published work in the field, we discuss below new developments and future directions that have the potential to further advance and establish NK cell-based therapies at the clinics on a broader scale.

  8. ERBB2/HER2-SPECIFIC NATURAL KILLER CELLS FOR ADOPTIVE IMMUNOTHERAPY OF GLIOBLASTOMA

    Science.gov (United States)

    Steinbach, Joachim P.; Zhang, Congcong; Burger, Michael; Jennewein, Lukas; Schönfeld, Kurt; Genßler, Sabrina; Sahm, Christiane; Brendel, Christian; Naundorf, Sonja; Odendahl, Marcus; Köhl, Ulrike; Nowakowska, Paulina; Seifried, Erhard; Bönig, Halvard; Tonn, Torsten; Grez, Manuel; Mittelbronn, Michel; Wels, Winfried S.

    2014-01-01

    BACKGROUND: While EGFRvIII appears a logical target for immunotherapy, only a subpopulation of tumor cells express EGFRvIII and immune escape has been demonstrated. ErbB2 is overexpressed in a substantial proportion of glioblastomas and has been successfully utilized in immunotherapies. Natural killer (NK) cells are the first line of defense against viral infections and malignant cells. The continuously growing cytotoxic cell line NK-92 holds promise for cancer immunotherapy. Safety of infusion of high doses of NK-92 was established in previous phase I clinical trials utilizing irradiated cells to prevent permanent engraftment. METHODS: To provide NK-92 cells with pre-determined tumor-cell specificity, we generated a lentiviral second generation chimeric antigen receptor (CAR) construct (5.28.z) employing the ErbB2 (HER2)-specific scFv(FRP5) antibody fragment for target cell recognition, and human CD28-CD3 ζ as a composite signaling moiety. An ErbB2-specific single cell clone (NK-92/5.28.z) was isolated, which showed high and selective cytotoxicity towards ErbB2-expressing tumor cells of various origins in vitro. We evaluated the cytotoxicity of NK-93/5.28.z cells against a panel of glioblastoma cell lines and primary glioblastoma cultures with different levels of Erb2 expression in vitro and in vivo. RESULTS: To provide NK-92 cells with pre-determined tumor-cell specificity, we generated a lentiviral second generation chimeric antigen receptor (CAR) construct (5.28.z) employing the ErbB2 (HER2)-specific scFv(FRP5) antibody fragment for target cell recognition, and human CD28-CD3 ζ as a composite signaling moiety. An ErbB2-specific single cell clone (NK-92/5.28.z) was isolated, which showed high and selective cytotoxicity towards ErbB2-expressing tumor cells of various origins in vitro. We evaluated the cytotoxicity of NK-93/5.28.z cells against a panel of glioblastoma cell lines and primary glioblastoma cultures with different levels of Erb2 expression in vitro

  9. Arctigenin, a natural lignan compound, induces G0/G1 cell cycle arrest and apoptosis in human glioma cells.

    Science.gov (United States)

    Maimaitili, Aisha; Shu, Zunhua; Cheng, Xiaojiang; Kaheerman, Kadeer; Sikandeer, Alifu; Li, Weimin

    2017-02-01

    The aim of the current study was to investigate the anticancer potential of arctigenin, a natural lignan compound, in malignant gliomas. The U87MG and T98G human glioma cell lines were treated with various concentrations of arctigenin for 48 h and the effects of arctigenin on the aggressive phenotypes of glioma cells were assessed. The results demonstrated that arctigenin dose-dependently inhibited the growth of U87MG and T98G cells, as determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and bromodeoxyuridine incorporation assays. Arctigenin exposure also induced a 60-75% reduction in colony formation compared with vehicle-treated control cells. However, arctigenin was not observed to affect the invasiveness of glioma cells. Arctigenin significantly increased the proportion of cells in the G 0 /G 1 phase and reduced the number of cells in the S phase, as compared with the control group (Parctigenin increased the expression levels of p21, retinoblastoma and p53 proteins, and significantly decreased the expression levels of cyclin D1 and cyclin-dependent kinase 4 proteins. Additionally, arctigenin was able to induce apoptosis in glioma cells, coupled with increased expression levels of cleaved caspase-3 and the pro-apoptotic BCL2-associated X protein. Furthermore, arctigenin-induced apoptosis was significantly suppressed by the pretreatment of cells with Z-DEVD-FMK, a caspase-3 inhibitor. In conclusion, the results suggest that arctigenin is able to inhibit cell proliferation and may induce apoptosis and cell cycle arrest at the G 0 /G 1 phase in glioma cells. These results warrant further investigation of the anticancer effects of arctigenin in animal models of gliomas.

  10. Neurofibromin 1 Impairs Natural Killer T-Cell-Dependent Antitumor Immunity against a T-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Jianyun Liu

    2018-01-01

    Full Text Available Neurofibromin 1 (NF1 is a tumor suppressor gene encoding a Ras GTPase that negatively regulates Ras signaling pathways. Mutations in NF1 are linked to neurofibromatosis type 1, juvenile myelomonocytic leukemia and Watson syndrome. In terms of antitumor immunity, CD1d-dependent natural killer T (NKT cells play an important role in the innate antitumor immune response. Generally, Type-I NKT cells protect (and Type-II NKT cells impair host antitumor immunity. We have previously shown that CD1d-mediated antigen presentation to NKT cells is regulated by cell signaling pathways. To study whether a haploinsufficiency in NF1 would affect CD1d-dependent activation of NKT cells, we analyzed the NKT-cell population as well as the functional expression of CD1d in Nf1+/− mice. Nf1+/− mice were found to have similar levels of NKT cells as wildtype (WT littermates. Interestingly, however, reduced CD1d expression was observed in Nf1+/− mice compared with their WT littermates. When inoculated with a T-cell lymphoma in vivo, Nf1+/− mice survived longer than their WT littermates. Furthermore, blocking CD1d in vivo significantly enhanced antitumor activity in WT, but not in Nf1+/− mice. In contrast, a deficiency in Type-I NKT cells increased antitumor activity in Nf1+/− mice, but not in WT littermates. Therefore, these data suggest that normal NF1 expression impairs CD1d-mediated NKT-cell activation and antitumor activity against a T-cell lymphoma.

  11. Transcriptional Changes during Naturally Acquired Zika Virus Infection Render Dendritic Cells Highly Conducive to Viral Replication.

    Science.gov (United States)

    Sun, Xiaoming; Hua, Stephane; Chen, Hsiao-Rong; Ouyang, Zhengyu; Einkauf, Kevin; Tse, Samantha; Ard, Kevin; Ciaranello, Andrea; Yawetz, Sigal; Sax, Paul; Rosenberg, Eric S; Lichterfeld, Mathias; Yu, Xu G

    2017-12-19

    Although dendritic cells are among the human cell population best equipped for cell-intrinsic antiviral immune defense, they seem highly susceptible to infection with the Zika virus (ZIKV). Using highly purified myeloid dendritic cells isolated from individuals with naturally acquired acute infection, we here show that ZIKV induces profound perturbations of transcriptional signatures relative to healthy donors. Interestingly, we noted a remarkable downregulation of antiviral interferon-stimulated genes and innate immune sensors, suggesting that ZIKV can actively suppress interferon-dependent immune responses. In contrast, several host factors known to support ZIKV infection were strongly upregulated during natural ZIKV infection; these transcripts included AXL, the main entry receptor for ZIKV; SOCS3, a negative regulator of ISG expression; and IDO-1, a recognized inducer of regulatory T cell responses. Thus, during in vivo infection, ZIKV can transform the transcriptome of dendritic cells in favor of the virus to render these cells highly conducive to ZIKV infection. Published by Elsevier Inc.

  12. Platelets impair natural killer cell reactivity and function in endometriosis through multiple mechanisms.

    Science.gov (United States)

    Du, Yanbo; Liu, Xishi; Guo, Sun-Wei

    2017-04-01

    Do platelets have any role in the reduced cytotoxicity of natural killer (NK) cells in endometriosis? Platelets impair NK cell reactivity and function in endometriosis through multiple mechanisms. Platelets play an important role in the development of endometriosis, and platelet-derived transforming growth factor-β1 (TGF-β1) suppresses the expression of NK Group 2, Member D (NKG2D) on NK cells, resulting in reduced cytotoxicity in women with endometriosis. Experiments on mice with induced endometriosis in which either platelets, NK cells or both were depleted and controls (none depleted). In vitro experiments with NK cells, platelets and, as target cells, endometriotic epithelial cell and endometrial stromal cell lines. Immunohistochemistry analysis of ectopic endometrial tissues from mice with induced endometriosis receiving either platelet depletion (PD), NK cell depletion, or both or none. Immunofluorescence, flow cytometry and gene expression analysis for major histocompatibility complex class I (MHC-I) expression in target cells. Cytotoxicity and degranulation assays and the measurement of interferon (IFN)-γ secretion for the evaluation of NK cytotoxicity. Flow cytometry and gene expression for the expression of NK cell receptors. PD resulted in significantly reduced lesion weight in mice with induced endometriosis, but NK cell depletion as well as concomitant platelet and NK cell depletion increased the weight, suggesting that the anti-endometriosis effect of PD is mediated, at least in part, by increased NK cell cytotoxicity against endometriotic cells. Co-incubation of target cells with platelets resulted in rapid platelet coating as well as increased MHC-I expression in these cells, effectively providing a cloak of 'pseudo-self' to these cells to shield against NK cell lysis. It also reduced the expression of NKG2D ligands MICA and MICB and reduced the NK cell cytotoxicity. In addition, co-incubation of NK cells with platelets impaired the NK cell

  13. Wall extensibility: its nature, measurement and relationship to plant cell growth

    Science.gov (United States)

    Cosgrove, D. J.

    1993-01-01

    Expansive growth of plant cells is controlled principally by processes that loosen the wall and enable it to expand irreversibly. The central role of wall relaxation for cell expansion is reviewed. The most common methods for assessing the extension properties of plant cell walls ( wall extensibility') are described, categorized and assessed critically. What emerges are three fundamentally different approaches which test growing cells for their ability (a) to enlarge at different values of turgor, (b) to induce wall relaxation, and (c) to deform elastically or plastically in response to an applied tensile force. Analogous methods with isolated walls are similarly reviewed. The results of these different assays are related to the nature of plant cell growth and pertinent biophysical theory. I argue that the extensibilities' measured by these assays are fundamentally different from one another and that some are more pertinent to growth than others.

  14. Control of immune ligands by members of a cytomegalovirus gene expansion suppresses natural killer cell activation.

    Science.gov (United States)

    Fielding, Ceri A; Weekes, Michael P; Nobre, Luis V; Ruckova, Eva; Wilkie, Gavin S; Paulo, Joao A; Chang, Chiwen; Suárez, Nicolás M; Davies, James A; Antrobus, Robin; Stanton, Richard J; Aicheler, Rebecca J; Nichols, Hester; Vojtesek, Borek; Trowsdale, John; Davison, Andrew J; Gygi, Steven P; Tomasec, Peter; Lehner, Paul J; Wilkinson, Gavin W G

    2017-02-10

    The human cytomegalovirus (HCMV) US12 family consists of ten sequentially arranged genes (US12-21) with poorly characterized function. We now identify novel natural killer (NK) cell evasion functions for four members: US12, US14, US18 and US20. Using a systematic multiplexed proteomics approach to quantify ~1300 cell surface and ~7200 whole cell proteins, we demonstrate that the US12 family selectively targets plasma membrane proteins and plays key roles in regulating NK ligands, adhesion molecules and cytokine receptors. US18 and US20 work in concert to suppress cell surface expression of the critical NKp30 ligand B7-H6 thus inhibiting NK cell activation. The US12 family is therefore identified as a major new hub of immune regulation.

  15. LiFePO{sub 4}/gel/natural graphite cells for the BATT program

    Energy Technology Data Exchange (ETDEWEB)

    Striebel, K.; Guerfi, A.; Shim, J.; Armand, M.; Gauthier, M.; Zaghib, K.

    2002-10-29

    LiFePO{sub 4}/gel/natural graphite (NG) cells have been prepared and cycled under a fixed protocol for cycle and calendar life determination. Cell compression of 10 psi was found to represent an optimal balance between cell impedance and the first cycle losses on the individual electrodes with the gel electrolyte. Cells with a Li anode showed capacities of 160 and 78 mAh/g-LiFePO{sub 4} for C/25 and 2C discharge rates, respectively. Rapid capacity and power fade were observed in the LiFePO{sub 4}/gel/NG cells during cycling and calendar life studies. Diagnostic evaluations point to the consumption of cycleable Li though a side reaction as the reason for performance fade with minimal degradation of the individual electrodes.

  16. Natural Compounds as Occult Ototoxins? Ginkgo biloba Flavonoids Moderately Damage Lateral Line Hair Cells.

    Science.gov (United States)

    Neveux, Sarah; Smith, Nicole K; Roche, Anna; Blough, Bruce E; Pathmasiri, Wimal; Coffin, Allison B

    2017-04-01

    Several drugs, including aminoglycosides and platinum-based chemotherapy agents, are well known for their ototoxic properties. However, FDA-approved drugs are not routinely tested for ototoxicity, so their potential to affect hearing often goes unrecognized. This issue is further compounded for natural products, where there is a lack of FDA oversight and the manufacturer is solely responsible for ensuring the safety of their products. Natural products such as herbal supplements are easily accessible and commonly used in the practice of traditional eastern and alternative medicine. Using the zebrafish lateral line, we screened a natural products library to identify potential ototoxins. We found that the flavonoids quercetin and kaempferol, both from the Gingko biloba plant, demonstrated significant ototoxicity, killing up to 30 % of lateral line hair cells. We then examined a third Ginkgo flavonoid, isorhamnetin, and found similar levels of ototoxicity. After flavonoid treatment, surviving hair cells demonstrated reduced uptake of the vital dye FM 1-43FX, suggesting that the health of the remaining hair cells was compromised. We then asked if these flavonoids enter hair cells through the mechanotransduction channel, which is the site of entry for many known ototoxins. High extracellular calcium or the quinoline derivative E6 berbamine significantly protected hair cells from flavonoid damage, implicating the transduction channel as a site of flavonoid uptake. Since known ototoxins activate cellular stress responses, we asked if reactive oxygen species were necessary for flavonoid ototoxicity. Co-treatment with the antioxidant D-methionine significantly protected hair cells from each flavonoid, suggesting that antioxidant therapy could prevent hair cell loss. How these products affect mammalian hair cells is still an open question and will be the target of future experiments. However, this research demonstrates the potential for ototoxic damage caused by unregulated

  17. Stem cell factor and interleukin-2/15 combine to enhance MAPK-mediated proliferation of human natural killer cells

    Science.gov (United States)

    Benson, Don M.; Yu, Jianhua; Becknell, Brian; Wei, Min; Freud, Aharon G.; Ferketich, Amy K.; Trotta, Rossana; Perrotti, Danilo; Briesewitz, Roger

    2009-01-01

    Stem cell factor (SCF) promotes synergistic cellular proliferation in combination with several growth factors, and appears important for normal natural killer (NK)–cell development. CD34+ hematopoietic precursor cells (HPCs) require interleukin-15 (IL-15) for differentiation into human NK cells, and this effect can be mimicked by IL-2. Culture of CD34+ HPCs or some primary human NK cells in IL-2/15 and SCF results in enhanced growth compared with either cytokine alone. The molecular mechanisms responsible for this are unknown and were investigated in the present work. Activation of NK cells by IL-2/15 increases expression of c-kit whose kinase activity is required for synergy with IL-2/15 signaling. Mitogen-activated protein kinase (MAPK) signaling intermediaries that are activated both by SCF and IL-2/15 are enhanced in combination to facilitate earlier cell-cycle entry. The effect results at least in part via enhanced MAPK-mediated modulation of p27 and CDK4. Collectively the data reveal a novel mechanism by which SCF enhances cellular proliferation in combination with IL-2/15 in primary human NK cells. PMID:19060242

  18. Dye-sensitized solar cells with natural dyes extracted from achiote seeds

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Ortiz, N.M.; Vazquez-Maldonado, I.A.; Azamar-Barrios, J.A.; Oskam, G. [Departamento de Fisica Aplicada, CINVESTAV-IPN, Merida, Yuc. 97310 (Mexico); Perez-Espadas, A.R.; Mena-Rejon, G.J. [Laboratorio de Quimica Organica de Investigacion, Facultad de Quimica, Universidad Autonoma de Yucatan, Merida, Yuc. 97150 (Mexico)

    2010-01-15

    We have explored the application of natural dyes extracted from the seeds of the achiote shrub (Bixa orellana L.) in dye-sensitized solar cells (DSCs). The main pigments are bixin and norbixin, which were obtained by separation and purification from the dark-red extract (annatto). The dyes were characterized using {sup 1}H-NMR, FTIR spectroscopy, and UV-Vis spectrophotometry. Solar cells were prepared using TiO{sub 2} and ZnO nanostructured, mesoporous films and the annatto, bixin, and norbixin as sensitizers. The best results were obtained with bixin-sensitized TiO{sub 2} solar cells with efficiencies of up to 0.53%, illustrating the importance of purification of dyes from natural extracts. (author)

  19. Natural product β-thujaplicin inhibits homologous recombination repair and sensitizes cancer cells to radiation therapy.

    Science.gov (United States)

    Zhang, Lihong; Peng, Yang; Uray, Ivan P; Shen, Jianfeng; Wang, Lulu; Peng, Xiangdong; Brown, Powel H; Tu, Wei; Peng, Guang

    2017-12-01

    Investigation of natural products is an attractive strategy to identify novel compounds for cancer prevention and treatment. Numerous studies have shown the efficacy and safety of natural products, and they have been widely used as alternative treatments for a wide range of illnesses, including cancers. However, it remains unknown whether natural products affect homologous recombination (HR)-mediated DNA repair and whether these compounds can be used as sensitizers with minimal toxicity to improve patients' responses to radiation therapy, a mainstay of treatment for many human cancers. In this study, in order to systematically identify natural products with an inhibitory effect on HR repair, we developed a high-throughput image-based HR repair screening assay and screened a chemical library containing natural products. Among the most interesting of the candidate compounds identified from the screen was β-thujaplicin, a bioactive compound isolated from the heart wood of plants in the Cupressaceae family, can significantly inhibit HR repair. We further demonstrated that β-thujaplicin inhibits HR repair by reducing the recruitment of a key HR repair protein, Rad51, to DNA double-strand breaks. More importantly, our results showed that β-thujaplicin can radiosensitize cancer cells. Additionally, β-thujaplicin sensitizes cancer cells to PARP inhibitor in different cancer cell lines. Collectively, our findings for the first time identify natural compound β-thujaplicin, which has a good biosafety profile, as a novel HR repair inhibitor with great potential to be translated into clinical applications as a sensitizer to DNA-damage-inducing treatment such as radiation and PARP inhibitor. In addition, our study provides proof of the principle that our robust high-throughput functional HR repair assay can be used for a large-scale screening system to identify novel natural products that regulate DNA repair and cellular responses to DNA damage-inducing treatments such as

  20. Contribution of Schwann Cells to Remyelination in a Naturally Occurring Canine Model of CNS Neuroinflammation.

    Directory of Open Access Journals (Sweden)

    Kristel Kegler

    with p75NTR/Sox2-positive cells. This study provides novel insights into the involvement of Schwann cells in CNS remyelination under natural occurring CNS inflammation. Targeting p75NTR/Sox2-expressing Schwann cells to enhance their differentiation into competent remyelinating cells appears to be a promising therapeutic approach for inflammatory/demyelinating CNS diseases.

  1. ACTIVITY OF NATURAL KILLER CELLS IN BIOLOGICAL FLUIDS FROM PATIENTS WITH COLORECTAL AND OVARIAN CANCERS

    Directory of Open Access Journals (Sweden)

    N. V. Yunusova

    2017-01-01

    Full Text Available Objective. To compare the functional activity of natural killer cells in peripheral blood and ascites from patients with different stages of colorectal and ovarian cancers and benign ovarian tumors. Material and methods. The study included 10 patients with stage IIIC ovarian cancer (FIGO, 2009, 5 patients with benign ovarian tumors (BOTs, and 15 patients with colorectal cancer (T2–4N0–2M0 . The control group consisted of 5 healthy donors. To evaluate the number and functional activity of NK-cells in peripheral blood and ascites, the FACS Canto II Flow Cytometer was used. Results. In peripheral blood of patients with ovarian and colorectal cancers, the relative number of activated NK-cells capable of secreting granzyme B (GB (CD56 + CD107a + GB + PF- was significantly lower and the proportion of degranulated NK-cells (CD56 + CD107a + GB- PF- was higher than those of healthy donors. Low total NK-cell counts in peripheral blood were a distinctive feature of ovarian cancer patients (p<0.05. The proportion of activated peripheral blood NK-cells, containing granules of cytolytic enzymes GB and perforin (PF increased with tumor growth. However, lymph node metastasis in patients with colorectal cancer did not affect the level and activation of NK-cells. The comparative analysis of NK-populations in patients with benign and malignant ovarian tumors revealed that the level of CD56 + cells was significantly higher in tumor ascites compared to peripheral blood. In patients with BTs, the levels of CD56 + CD107a + and activated CD56 + CD107a + GB-PF-degranulated cells was higher in ascites than in blood. In patients with ovarian cancer, the level of degranulated cells was higher in peripheral blood than in malignant ascites. Conclusion. The tumor cells and tumor microenvironment were found to affect the number and the functional activity of NK-cells. The accumulation of free fluid within the peritoneal cavity in patients with both benign and malignant

  2. Lineage tracing of resident tendon progenitor cells during growth and natural healing.

    Directory of Open Access Journals (Sweden)

    Nathaniel A Dyment

    Full Text Available Unlike during embryogenesis, the identity of tissue resident progenitor cells that contribute to postnatal tendon growth and natural healing is poorly characterized. Therefore, we utilized 1 an inducible Cre driven by alpha smooth muscle actin (SMACreERT2, that identifies mesenchymal progenitors, 2 a constitutively active Cre driven by growth and differentiation factor 5 (GDF5Cre, a critical regulator of joint condensation, in combination with 3 an Ai9 Cre reporter to permanently label SMA9 and GDF5-9 populations and their progeny. In growing mice, SMA9+ cells were found in peritendinous structures and scleraxis-positive (ScxGFP+ cells within the tendon midsubstance and myotendinous junction. The progenitors within the tendon midsubstance were transiently labeled as they displayed a 4-fold expansion from day 2 to day 21 but reduced to baseline levels by day 70. SMA9+ cells were not found within tendon entheses or ligaments in the knee, suggesting a different origin. In contrast to the SMA9 population, GDF5-9+ cells extended from the bone through the enthesis and into a portion of the tendon midsubstance. GDF5-9+ cells were also found throughout the length of the ligaments, indicating a significant variation in the progenitors that contribute to tendons and ligaments. Following tendon injury, SMA9+ paratenon cells were the main contributors to the healing response. SMA9+ cells extended over the defect space at 1 week and differentiated into ScxGFP+ cells at 2 weeks, which coincided with increased collagen signal in the paratenon bridge. Thus, SMA9-labeled cells represent a unique progenitor source that contributes to the tendon midsubstance, paratenon, and myotendinous junction during growth and natural healing, while GDF5 progenitors contribute to tendon enthesis and ligament development. Understanding the mechanisms that regulate the expansion and differentiation of these progenitors may prove crucial to improving future repair strategies.

  3. Synergistic apoptotic response between valproic acid and fludarabine in chronic lymphocytic leukaemia (CLL) cells involves the lysosomal protease cathepsin B

    International Nuclear Information System (INIS)

    Yoon, J-Y; Szwajcer, D; Ishdorj, G; Benjaminson, P; Xiao, W; Kumar, R; Johnston, J B; Gibson, S B

    2013-01-01

    Fludarabine, a nucleoside analogue, is commonly used in combination with other agents for the treatment of chronic lymphocytic leukaemia (CLL). In previous studies, valproic acid (VPA), an inhibitor of histone deacetylases, combined with fludarabine to synergistically increase apoptotic cell death in CLL cells. In the present study, we found that the combination of fludarabine and VPA decreases the level of the anti-apoptotic proteins Mcl-1 and XIAP in primary CLL cells. Treatment with fludarabine alone, or in combination with VPA, led to the loss of lysosome integrity, and chemical inhibition of the lysosomal protease cathepsin B, using CA074-Me, was sufficient to reduce apoptosis. VPA treatment increased cathepsin B levels and activities in primary CLL cells, thereby priming CLL cells for lysosome-mediated cell death. Six previously treated patients with relapsed CLL were treated with VPA, followed by VPA/fludarabine combination. The combined therapy resulted in reduced lymphocyte count in five out of six and reduced lymph node sizes in four out of six patients. In vivo VPA treatment increased histone-3 acetylation and cathepsin B expression levels. Thus, the synergistic apoptotic response with VPA and fludarabine in CLL is mediated by cathepsin B activation leading to a decrease in the anti-apoptotic proteins

  4. HIV/SIV infection primes monocytes and dendritic cells for apoptosis.

    Directory of Open Access Journals (Sweden)

    Mireille Laforge

    2011-06-01

    Full Text Available Subversion or exacerbation of antigen-presenting cells (APC death modulates host/pathogen equilibrium. We demonstrated during in vitro differentiation of monocyte-derived macrophages and monocyte-derived dendritic cells (DCs that HIV sensitizes the cells to undergo apoptosis in response to TRAIL and FasL, respectively. In addition, we found that HIV-1 increased the levels of pro-apoptotic Bax and Bak molecules and decreased the levels of anti-apoptotic Mcl-1 and FLIP proteins. To assess the relevance of these observations in the context of an experimental model of HIV infection, we investigated the death of APC during pathogenic SIV-infection in rhesus macaques (RMs. We demonstrated increased apoptosis, during the acute phase, of both peripheral blood DCs and monocytes (CD14(+ from SIV(+RMs, associated with a dysregulation in the balance of pro- and anti-apoptotic molecules. Caspase-inhibitor and death receptors antagonists prevented apoptosis of APCs from SIV(+RMs. Furthermore, increased levels of FasL in the sera of pathogenic SIV(+RMs were detected, compared to non-pathogenic SIV infection of African green monkey. We suggest that inappropriate apoptosis of antigen-presenting cells may contribute to dysregulation of cellular immunity early in the process of HIV/SIV infection.

  5. Natural Dye-Sensitized Solar Cell Based on Nanocrystalline TiO2

    International Nuclear Information System (INIS)

    Jasim, K.E.

    2012-01-01

    During the last quarter of the twentieth century there have been intensive research activities looking for green sources of energy. The main aim of the green generators or converters of energy is to replace the conventional (fossil) energy sources, hence reducing further accumulation of the green house gasses GHGs. Conventional silicon and III-V semiconductor solar cell based on crystalline bulk, quantum well and quantum dots structure or amorphous and thin film structures provided a feasible solution. However, natural dye sensitized solar cells NDSSC are a promising class of photovoltaic cells with the capability of generating green energy at low production cost since no vacuum systems or expensive equipment are required in their fabrication. Also, natural dyes are abundant, easily extracted and safe materials. In NDSSC, once dye molecules exposed to light they become oxidized and transfer electrons to a nano structured layer of wide bandgap semiconductors such as TiO 2 . The generated electrons are drawn outside the cell through ohmic contact to a load. In this paper we review the structure and operation principles of the dye sensitized solar cell DSSC. We discuss preparation procedures, optical and electrical characterization of the NDSSC using local dyes extracted from Henna (Lawsonia inermis L.), pomegranate, cherries and Bahraini raspberries (Rubus spp.). These natural organic dyes are potential candidates to replace some of the man-made dyes used as sensitizer in many commercialized photoelectrochemical cells. Factors limiting the operation of the DSSC are discussed. NDSSCs are expected to be a favored choice in the building-integrated photovoltaic (BIPV) due to their robustness, therefore, requiring no special shielding from natural events such as tree strikes or hails. (author)

  6. Invariant Natural Killer T Cells As Suppressors of Graft-versus-Host Disease in Allogeneic Hematopoietic Stem Cell Transplantation

    Directory of Open Access Journals (Sweden)

    Melissa Mavers

    2017-07-01

    Full Text Available Invariant natural killer T (iNKT cells serve as a bridge between innate and adaptive immunity and have been shown to play an important role in immune regulation, defense against pathogens, and cancer immunity. Recent data also suggest that this compartment of the immune system plays a significant role in reducing graft-versus-host disease (GVHD in the setting of allogeneic hematopoietic stem cell transplantation. Murine studies have shown that boosting iNKT numbers through certain conditioning regimens or adoptive transfer leads to suppression of acute or chronic GVHD. Preclinical work reveals that iNKT cells exert their suppressive function by expanding regulatory T cells in vivo, though the exact mechanism by which this occurs has yet to be fully elucidated. Human studies have demonstrated that a higher number of iNKT cells in the graft or in the peripheral blood of the recipient post-transplantation are associated with a reduction in GVHD risk, importantly without a loss of graft-versus-tumor effect. In two separate analyses of many immune cell subsets in allogeneic grafts, iNKT cell dose was the only parameter associated with a significant improvement in GVHD or in GVHD-free progression-free survival. Failure to reconstitute iNKT cells following allogeneic transplantation has also been associated with an increased risk of relapse. These data demonstrate that iNKT cells hold promise for future clinical application in the prevention of GVHD in allogeneic stem cell transplantation and warrant further study of the immunoregulatory functions of iNKT cells in this setting.

  7. Natural killer cells in obesity: impaired function and increased susceptibility to the effects of cigarette smoke.

    LENUS (Irish Health Repository)

    O'Shea, Donal

    2012-02-01

    BACKGROUND: Obese individuals who smoke have a 14 year reduction in life expectancy. Both obesity and smoking are independently 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\\/m(2)) 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.

  8. Characterization and ex vivo Expansion of Human Placenta-Derived Natural Killer Cells for Cancer Immunotherapy

    Directory of Open Access Journals (Sweden)

    Xiaokui eZhang

    2013-05-01

    Full Text Available Recent clinical studies suggest that adoptive transfer of donor-derived natural killer (NK cells may improve clinical outcome in hematological malignancies and some solid tumors by direct antitumor effects as well as by reduction of graft versus host disease (GVHD. NK cells have also been shown to enhance transplant engraftment during allogeneic hematopoietic stem cell transplantation (HSCT for hematological malignancies. The limited ex vivo expansion potential of NK cells from peripheral blood (PB or umbilical cord blood (UCB has however restricted their therapeutic potential. Here we define methods to efficiently generate NK cells from donor matched, full-term human placenta perfusate (termed Human Placenta-Derived Stem Cell, HPDSC and UCB. Following isolation from cryopreserved donor-matched HPDSC and UCB units, CD56+CD3- placenta-derived NK cells, termed pNK cells, were expanded in culture for up to 3 weeks to yield an average of 1.2 billion cells per donor that were >80% CD56+CD3-, comparable to doses previously utilized in clinical applications. Ex vivo-expanded pNK cells exhibited a marked increase in anti-tumor cytolytic activity coinciding with the significantly increased expression of NKG2D, NKp46 and NKp44 (p < 0.001, p < 0.001, and p < 0.05, respectively. Strong cytolytic activity was observed against a wide range of tumor cell lines in vitro. pNK cells display a distinct microRNA (miRNA expression profile, immunophenotype and greater antitumor capacity in vitro compared to PB NK cells used in recent clinical trials. With further development, pNK may represent a novel and effective cellular immunotherapy for patients with high clinical needs and few other therapeutic options.

  9. Characterization and ex vivo Expansion of Human Placenta-Derived Natural Killer Cells for Cancer Immunotherapy

    Science.gov (United States)

    Kang, Lin; Voskinarian-Berse, Vanessa; Law, Eric; Reddin, Tiffany; Bhatia, Mohit; Hariri, Alexandra; Ning, Yuhong; Dong, David; Maguire, Timothy; Yarmush, Martin; Hofgartner, Wolfgang; Abbot, Stewart; Zhang, Xiaokui; Hariri, Robert

    2013-01-01

    Recent clinical studies suggest that adoptive transfer of donor-derived natural killer (NK) cells may improve clinical outcome in hematological malignancies and some solid tumors by direct anti-tumor effects as well as by reduction of graft versus host disease (GVHD). NK cells have also been shown to enhance transplant engraftment during allogeneic hematopoietic stem cell transplantation (HSCT) for hematological malignancies. The limited ex vivo expansion potential of NK cells from peripheral blood (PB) or umbilical cord blood (UCB) has however restricted their therapeutic potential. Here we define methods to efficiently generate NK cells from donor-matched, full-term human placenta perfusate (termed Human Placenta-Derived Stem Cell, HPDSC) and UCB. Following isolation from cryopreserved donor-matched HPDSC and UCB units, CD56+CD3− placenta-derived NK cells, termed pNK cells, were expanded in culture for up to 3 weeks to yield an average of 1.2 billion cells per donor that were >80% CD56+CD3−, comparable to doses previously utilized in clinical applications. Ex vivo-expanded pNK cells exhibited a marked increase in anti-tumor cytolytic activity coinciding with the significantly increased expression of NKG2D, NKp46, and NKp44 (p < 0.001, p < 0.001, and p < 0.05, respectively). Strong cytolytic activity was observed against a wide range of tumor cell lines in vitro. pNK cells display a distinct microRNA (miRNA) expression profile, immunophenotype, and greater anti-tumor capacity in vitro compared to PB NK cells used in recent clinical trials. With further development, pNK may represent a novel and effective cellular immunotherapy for patients with high clinical needs and few other therapeutic options. PMID:23641243

  10. Activation of human natural killer cells by the soluble form of cellular prion protein

    Energy Technology Data Exchange (ETDEWEB)

    Seong, Yeon-Jae [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Hafis Clinic, Seoul (Korea, Republic of); Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Bum-Chan [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Park, Su-Hyung [Laboratory of Translational Immunology and Vaccinology, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of); Park, Young Woo [Aging Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon (Korea, Republic of); Shin, Eui-Cheol, E-mail: ecshin@kaist.ac.kr [Laboratory of Immunology and Infectious Diseases, Graduate School of Medical Science and Engineering, KAIST, Daejeon (Korea, Republic of)

    2015-08-21

    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 the 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.

  11. Activation of human natural killer cells by the soluble form of cellular prion protein

    International Nuclear Information System (INIS)

    Seong, Yeon-Jae; Sung, Pil Soo; Jang, Young-Soon; Choi, Young Joon; Park, Bum-Chan; Park, Su-Hyung; Park, Young Woo; Shin, Eui-Cheol

    2015-01-01

    Cellular prion protein (PrP C ) is widely expressed in various cell types, including cells of the immune system. However, the specific roles of PrP 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 C protein on human natural killer (NK) cells. Recombinant soluble PrP C protein was generated by fusion of human PrP C with the Fc portion of human IgG 1 (PrP C -Fc). PrP C -Fc binds to the surface of human NK cells, particularly to CD56 dim NK cells. PrP C -Fc induced the production of cytokines and chemokines and the degranulation of granzyme B from NK cells. In addition, PrP C -Fc facilitated the IL-15-induced proliferation of NK cells. PrP C -Fc induced phosphorylation of ERK-1/2 and JNK in NK cells, and inhibitors of the ERK or the JNK pathways abrogated PrP C -Fc-induced cytokine production in NK cells. In conclusion, the soluble form of recombinant PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways. - Highlights: • Recombinant soluble PrP C (PrP C -Fc) was generated by fusion of human PrP C with IgG1 Fc portion. • PrP C -Fc protein induces the production of cytokines and degranulation from human NK cells. • PrP C -Fc protein enhances the IL-15-induced proliferation of human NK cells. • PrP C -Fc protein activates human NK cells via the ERK and JNK signaling pathways

  12. Natural killer cells in obesity: impaired function and increased susceptibility to the effects of cigarette smoke.

    LENUS (Irish Health Repository)

    O'Shea, Donal

    2010-01-01

    BACKGROUND: Obese individuals who smoke have a 14 year reduction in life expectancy. Both obesity and smoking are independently 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\\/m(2)) 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.

  13. Natural killer cells in obesity: impaired function and increased susceptibility to the effects of cigarette smoke.

    Directory of Open Access Journals (Sweden)

    Donal O'Shea

    Full Text Available BACKGROUND: Obese individuals who smoke have a 14 year reduction in life expectancy. Both obesity and smoking are independently 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/m(2 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.

  14. Natural killer T (NKT cells accelerate Shiga toxin type 2 (Stx2 pathology in mice

    Directory of Open Access Journals (Sweden)

    Fumiko eObata

    2015-04-01

    Full Text Available Shiga toxin-producing Escherichia coli (STEC is a leading cause of childhood renal disease He-molytic Uremic Syndrome (HUS. The involvement of renal cytokines and chemokines is sus-pected to play a critical role in disease progression. In current article, we tested the hypothesis that NKT cells are involved in Stx2-induced pathology in vivo. To address this hypothesis we compared Stx2 toxicity in WT and CD1 knockout (KO mice. In CD1KO mice, which lack nat-ural killer T (NKT cells, Stx2-induced pathologies such as weight loss, renal failure, and death were delayed. In WT mice, Stx2-specific selective increase in urinary albumin occurs in later time points, and this was also delayed in NKT cell deficient mice. NKT cell-associated cytokines such as IL-2, IL-4, IFN-γ and IL-17 were detected in kidney lysates of Stx2-injected WT mice with the peak around 36 h after Stx2 injection. In CD1KO, there was a delay in the kinetics, and increases in these cytokines were observed 60 h post Stx2 injection. These data suggest that NKT cells accelerate Stx2-induced pathology in mouse kidneys. To determine the mechanism by which NKT cells promote Stx2-associated disease, in vitro studies were performed using murine renal cells. We found that murine glomerular endothelial cells and podocytes express functional CD1d molecules and can present exogenous antigen to NKT cells. Moreover, we observed the direct interaction between Stx2 and the receptor Gb3 on the surface of mouse renal cells by 3D STORM-TIRF which provides single molecule imaging. Collectively, these data suggest that Stx2 binds to Gb3 on renal cells and leads to aberrant CD1d-mediated NKT cell activation. Therefore, strategies targeting NKT cells could have a significant impact on Stx2-associated renal pathology in STEC disease.

  15. Natural killer T (NKT) cells accelerate Shiga toxin type 2 (Stx2) pathology in mice.

    Science.gov (United States)

    Obata, Fumiko; Subrahmanyam, Priyanka B; Vozenilek, Aimee E; Hippler, Lauren M; Jeffers, Tynae; Tongsuk, Methinee; Tiper, Irina; Saha, Progyaparamita; Jandhyala, Dakshina M; Kolling, Glynis L; Latinovic, Olga; Webb, Tonya J

    2015-01-01

    Shiga toxin-producing Escherichia coli (STEC) is a leading cause of childhood renal disease Hemolytic Uremic Syndrome (HUS). The involvement of renal cytokines and chemokines is suspected to play a critical role in disease progression. In current article, we tested the hypothesis that NKT cells are involved in Stx2-induced pathology in vivo. To address this hypothesis we compared Stx2 toxicity in WT and CD1 knockout (KO) mice. In CD1KO mice, which lack natural killer T (NKT) cells, Stx2-induced pathologies such as weight loss, renal failure, and death were delayed. In WT mice, Stx2-specific selective increase in urinary albumin occurs in later time points, and this was also delayed in NKT cell deficient mice. NKT cell-associated cytokines such as IL-2, IL-4, IFN-γ, and IL-17 were detected in kidney lysates of Stx2-injected WT mice with the peak around 36 h after Stx2 injection. In CD1KO, there was a delay in the kinetics, and increases in these cytokines were observed 60 h post Stx2 injection. These data suggest that NKT cells accelerate Stx2-induced pathology in mouse kidneys. To determine the mechanism by which NKT cells promote Stx2-associated disease, in vitro studies were performed using murine renal cells. We found that murine glomerular endothelial cells and podocytes express functional CD1d molecules and can present exogenous antigen to NKT cells. Moreover, we observed the direct interaction between Stx2 and the receptor Gb3 on the surface of mouse renal cells by 3D STORM-TIRF which provides single molecule imaging. Collectively, these data suggest that Stx2 binds to Gb3 on renal cells and leads to aberrant CD1d-mediated NKT cell activation. Therefore, strategies targeting NKT cells could have a significant impact on Stx2-associated renal pathology in STEC disease.

  16. Invariant Natural Killer T Cells Ameliorate Monosodium Urate Crystal-Induced Gouty Inflammation in Mice

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    Jie Wang

    2017-12-01

    Full Text Available Gout is an inflammatory arthritis caused by deposition of intra-articular monosodium urate (MSU crystal. Previous studies have focused on resident macrophage, infiltrating monocyte, and neutrophil responses to MSU crystal; yet the mechanisms of cellular changes and the potential involvement of other regulatory immune cells remain largely unknown. Invariant natural killer T (iNKT cells, an innate type of T cell, are involved in the development of various inflammatory diseases. Here, we investigate the role of iNKT cells in MSU crystal-induced gouty inflammation. MSU crystal-induced inflammatory profiles in an air-pouch model were examined in iNKT-deficient CD1d knockout (KO and wild-type (WT control mice. To explore potential mechanisms of iNKT cell regulation of gouty inflammation, we cocultured CD4+ or CD4−iNKT cells with bone marrow-derived macrophages (BMDMs. We found that iNKT cells quickly migrated to the site of inflammation upon MSU crystal stimulation in WT mice. The total number of infiltrating cells in CD1d KO mice, especially neutrophils, was dramatically increased at 6 and 12 h (P < 0.01 post-MSU crystal challenge, compared with WT controls. BMDMs cocultured with CD4+iNKT cells produced less tumor necrosis factor-α and expressed higher levels of M2 macrophage markers, including Clec7a, Pdcd1Ig2, and interleukin-4 (P < 0.01, compared with BMDMs cocultured with CD4−iNKT cells or conventional CD4+ T cells. CD4+iNKT cells are one of the key regulators of MSU crystal-induced gouty inflammation through the control of macrophage polarization. iNKT cells may serve as a new therapeutic target for gout.

  17. Natural Killer (NK- and T-Cell Engaging Antibody-Derived Therapeutics

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    Christoph Stein

    2012-06-01

    Full Text Available Unmodified antibodies (abs have been successful in the treatment of hematologic malignancies, but less so for the treatment of solid tumors. They trigger anti-tumor effects through their Fc-domains, and one way to improve their efficacy is to optimize their interaction with the effectors through Fc-engineering. Another way to empower abs is the design of bispecific abs and related fusion proteins allowing a narrower choice of effector cells. Here we review frequently chosen classes of effector cells, as well as common trigger molecules. Natural Killer (NK- and T-cells are the most investigated populations in therapeutical approaches with bispecific agents until now. Catumaxomab, the first bispecific ab to receive drug approval, targets the tumor antigen Epithelial Cell Adhesion Molecule (EpCAM and recruits T-cells via a binding site for the cell surface protein CD3. The next generation of recombinant ab-derivatives replaces the broadly reactive Fc-domain by a binding domain for a single selected trigger. Blinatumomab is the first clinically successful member of this class, targeting cancer cells via CD19 and engaging T-cells by CD3. Other investigators have developed related recombinant fusion proteins to recruit effectors, such as NK-cells and macrophages. The first such agents currently in preclinical and clinical development will be discussed.

  18. Tumor necrosis factor-α enhances IL-15-induced natural killer cell differentiation

    International Nuclear Information System (INIS)

    Lee, Jiwon; Lee, Suk Hyung; Shin, Nara; Jeong, Mira; Kim, Mi Sun; Kim, Mi Jeong; Yoon, Suk Ran; Chung, Jin Woong; Kim, Tae-Don; Choi, Inpyo

    2009-01-01

    The differentiation of natural killer (NK) cells is regulated by various factors including soluble growth factors and transcription factors. Here, we have demonstrated that tumor necrosis factor-α (TNF-α) is a positive regulator of NK cell differentiation. TNF-α augmented the IL-15-induced expression of NK1.1 and CD122 in mature NK cells, and TNF-α alone also induced NK cell maturation as well as IL-15. TNF-α also increased IFN-γ production in NK cells in the presence of IL-15. Meanwhile, mRNA expression of several transcription factors, including T-bet and GATA-3, was increased by the addition of TNF-α and IL-15. In addition, TNF-α increased nuclear factor-kappa B (NF-κB) activity in NK cells and inhibition of NF-κB impeded TNF-α-enhanced NK cell maturation. Overall, these data suggest that TNF-α significantly increased IL-15-driven NK cell differentiation by increasing the expression of transcription factors that play crucial roles in NK cell maturation and inducing the NF-κB activity.

  19. NKp80 Defines a Critical Step during Human Natural Killer Cell Development

    Directory of Open Access Journals (Sweden)

    Aharon G. Freud

    2016-07-01

    Full Text Available Human natural killer (NK cells develop in secondary lymphoid tissues (SLTs through distinct stages. We identified two SLT lineage (Lin−CD34−CD117+/−CD94+CD16− “stage 4” subsets according to expression of the C-type lectin-like surface-activating receptor, NKp80: NKp80− (stage “4a” and NKp80+ (stage “4b”. Whereas stage 4b cells expressed more of the transcription factors T-BET and EOMES, produced interferon-gamma, and were cytotoxic, stage 4a cells expressed more of the transcription factors RORγt and AHR and produced interleukin-22, similar to SLT Lin−CD34−CD117+CD94−CD16− “stage 3” cells, whose phenotype overlaps with that of group 3 innate lymphoid cells (ILC3s. Co-culture with dendritic cells or transplantation into immunodeficient mice produced mature NK cells from stage 3 and stage 4a populations. These data identify NKp80 as a marker of NK cell maturity in SLTs and support a model of human NK cell development through a stage 4a intermediate with ILC3-associated features.

  20. Natural killer cells regulate Th1/Treg and Th17/Treg balance in chlamydial lung infection.

    Science.gov (United States)

    Li, Jing; Dong, Xiaojing; Zhao, Lei; Wang, Xiao; Wang, Yan; Yang, Xi; Wang, Hong; Zhao, Weiming

    2016-07-01

    Natural killer (NK) cell is an important component in innate immunity, playing a critical role in bridging innate and adaptive immunity by modulating the function of other immune cells including T cells. In this study, we focused on the role of NK cells in regulating Th1/Treg and Th17/Treg balance during chlamydial lung infection. We found that NK cell-depleted mice showed decreased Th1 and Th17 cells, which was correlated with reduced interferon-γ, interleukin (IL)-12, IL-17 and IL-22 production as well as T-bet and receptor-related orphan receptor gamma t expression compared with mice treated with the isotype control antibody. In contrast, NK cell depletion significantly increased Treg in cell number and related transcription factor (Foxp3) expression. The opposite trends of changes of Th1/Th17 and Treg led to significant reduction in the Th1/Treg and Th17/Treg ratios. The data implicate that NK cells play an important role in host defence against chlamydial lung infection, mainly through maintaining Th1/Treg and Th17/Treg balance. © 2016 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  1. Korean mistletoe lectin enhances natural killer cell cytotoxicity via upregulation of perforin expression.

    Science.gov (United States)

    Kim, Younghoon; Kim, Inbo; Park, Choon-Ho; Kim, Jong Bae

    2018-03-31

    Natural killer (NK) cells are crucial components of the innate immune system, providing the first line of defense against pathogens. In a previous study, we demonstrated prophylactic activity of water extract of Korean mistletoe (Viscum album coloratum) on tumor metastasis. However, the leading compound from water extract of Korean mistletoe was not clearly addressed. The purpose of this research was mainly focused on addressing the effect of Korean mistletoe lectin (KMLC) on NK cell cytotoxicity, and the ability of cytokine secretion as well as its signal transduction, mitogen-activated protein kinase (MAPK) pathway. KMLC was used to test NK cell-mediated cytotoxicity in vitro and in vivo. Non-isotope cytotoxicity assay (bis-N,N,N',N'-tetraacetic acid (BATDA) release assay) was performed to test the cytotoxicity of NK cells against target tumor cells. Receptor expression was checked by flow cytometry analysis and MAPK signal molecules were analyzed by immunoblotting. KMLC at 200 ng/mL increased the cytotoxicity of NK92 cells by 35% compared with untreated cells. KMLC-treated (at 100 ng/mL) mice splenocytes showed a 20% increase in cytotoxic activity. Also, the B chain, one of the subchains of KMLC, increases perforin expression. We demonstrated that the signal transduction controlling NK cell cytotoxicity was mediated by upregulation of the NKG2D receptor and expression of a cytotoxic effector molecule. These results suggested that KMLC possessed immunological activity, mediated by NK cell activation.

  2. Susceptibility of human melanoma cells to autologous natural killer (NK cell killing: HLA-related effector mechanisms and role of unlicensed NK cells.

    Directory of Open Access Journals (Sweden)

    Paolo Carrega

    Full Text Available BACKGROUND: Despite Natural Killer (NK cells were originally defined as effectors of spontaneous cytotoxicity against tumors, extremely limited information is so far available in humans on their capability of killing cancer cells in an autologous setting. METHODOLOGY/PRINCIPAL FINDINGS: We have established a series of primary melanoma cell lines from surgically resected specimens and here showed that human melanoma cells were highly susceptible to lysis by activated autologous NK cells. A variety of NK cell activating receptors were involved in killing: particularly, DNAM-1 and NKp46 were the most frequently involved. Since self HLA class I molecules normally play a protective role from NK cell-mediated attack, we analyzed HLA class I expression on melanomas in comparison to autologous lymphocytes. We found that melanoma cells presented specific allelic losses in 50% of the patients analyzed. In addition, CD107a degranulation assays applied to NK cells expressing a single inhibitory receptor, revealed that, even when expressed, specific HLA class I molecules are present on melanoma cell surface in amount often insufficient to inhibit NK cell cytotoxicity. Remarkably, upon activation, also the so called "unlicensed" NK cells, i.e. NK cells not expressing inhibitory receptor specific for self HLA class I molecules, acquired the capability of efficiently killing autologous melanoma cells, thus additionally contributing to the lysis by a mechanism independent of HLA class I expression on melanoma cells. CONCLUSIONS/SIGNIFICANCE: We have investigated in details the mechanisms controlling the recognition and lysis of melanoma cells by autologous NK cells. In these autologous settings, we demonstrated an efficient in vitro killing upon NK cell activation by mechanisms that may be related or not to abnormalities of HLA class I expression on melanoma cells. These findings should be taken into account in the design of novel immunotherapy approaches

  3. Development of Antiatherosclerotic Drugs on the basis of Natural Products Using Cell Model Approach

    Directory of Open Access Journals (Sweden)

    Alexander N. Orekhov

    2015-01-01

    Full Text Available Atherosclerosis including its subclinical form is one of the key medical and social problems. At present, there is no therapy available for widespread use against subclinical atherosclerosis. The use of synthetic drugs for the prevention of arteriosclerosis in its early stages is not sufficient because of the limited indications for severe side effects and high cost of treatment. Obviously, effective antiatherosclerotic drugs based on natural products would be a preferred alternative. Simple cell-based models for testing different natural products have been developed and the ability of natural products to prevent intracellular lipid accumulation in primary cell culture was evaluated. This approach utilizing cell models allowed to test effects of such direct antiatherosclerotic therapy, analyzing the effects mimicking those which can occur “at the level” of arterial wall via the inhibition of intracellular lipid deposition. The data from the carried out clinical trials support a point of view that the identification of antiatherosclerotic activity of natural products might offer a great opportunity for the prevention and treatment of atherosclerotic disease, reducing cardiovascular morbidity and mortality.

  4. Intermediate Temperature Hybrid Fuel Cell System for the Conversion of Natural to Electricity and Liquid Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Krause, Theodore [Argonne National Lab. (ANL), Argonne, IL (United States)

    2017-11-22

    This goal of this project was to develop a new hybrid fuel cell technology that operates directly on natural gas or biogas to generate electrical energy and to produce ethane or ethylene from methane, the main component of natural gas or biogas, which can be converted to a liquid fuel or high-value chemical using existing process technologies. By taking advantage of the modularity and scalability of fuel cell technology, this combined fuel cell/chemical process technology targets the recovery of stranded natural gas available at the well pad or biogas produced at waste water treatment plants and municipal landfills by converting it to a liquid fuel or chemical. By converting the stranded gas to a liquid fuel or chemical, it can be cost-effectively transported to market thus allowing the stranded natural gas or biogas to be monetized instead of flared, producing CO2, a greenhouse gas, because the volumes produced at these locations are too small to be economically recovered using current gas-to-liquids process technologies.

  5. Theory of Connectivity: Nature and Nurture of Cell Assemblies and Cognitive Computation

    Directory of Open Access Journals (Sweden)

    Meng eLi

    2016-04-01

    Full Text Available Richard Semon and Donald Hebb are among the firsts to put forth the notion of cell assembly – a group of coherently or sequentially-activated neurons– to represent percept, memory, or concept. Despite the rekindled interest in this age-old idea, the concept of cell assembly still remains ill-defined and its operational principle is poorly understood. What is the size of a cell assembly? How should a cell assembly be organized? What is the computational logic underlying Hebbian cell assemblies? How might Nature vs Nurture interact at the level of a cell assembly? In contrast to the widely assumed local randomness within the mature but naïve cell assembly, the recent Theory of Connectivity postulates that the brain consists of the developmentally pre-programmed cell assemblies known as the functional connectivity motif (FCM. Principal cells within such FCM is organized by the power-of-two-based mathematical principle that guides the construction of specific-to-general combinatorial connectivity patterns in neuronal circuits, giving rise to a full range of specific features, various relational patterns, and generalized knowledge. This pre-configured canonical computation is predicted to be evolutionarily conserved across many circuits, ranging from these encoding memory engrams and imagination to decision-making and motor control. Although the power-of-two-based wiring and computational logic places a mathematical boundary on an individual’s cognitive capacity, the fullest intellectual potential can be brought about by optimized nature and nurture. This theory may also open up a new avenue to examining how genetic mutations and various drugs might impair or enhance the computational logic of brain circuits.

  6. Theory of Connectivity: Nature and Nurture of Cell Assemblies and Cognitive Computation.

    Science.gov (United States)

    Li, Meng; Liu, Jun; Tsien, Joe Z

    2016-01-01

    Richard Semon and Donald Hebb are among the firsts to put forth the notion of cell assembly-a group of coherently or sequentially-activated neurons-to represent percept, memory, or concept. Despite the rekindled interest in this century-old idea, the concept of cell assembly still remains ill-defined and its operational principle is poorly understood. What is the size of a cell assembly? How should a cell assembly be organized? What is the computational logic underlying Hebbian cell assemblies? How might Nature vs. Nurture interact at the level of a cell assembly? In contrast to the widely assumed randomness within the mature but naïve cell assembly, the Theory of Connectivity postulates that the brain consists of the developmentally pre-programmed cell assemblies known as the functional connectivity motif (FCM). Principal cells within such FCM is organized by the power-of-two-based mathematical principle that guides the construction of specific-to-general combinatorial connectivity patterns in neuronal circuits, giving rise to a full range of specific features, various relational patterns, and generalized knowledge. This pre-configured canonical computation is predicted to be evolutionarily conserved across many circuits, ranging from these encoding memory engrams and imagination to decision-making and motor control. Although the power-of-two-based wiring and computational logic places a mathematical boundary on an individual's cognitive capacity, the fullest intellectual potential can be brought about by optimized nature and nurture. This theory may also open up a new avenue to examining how genetic mutations and various drugs might impair or improve the computational logic of brain circuits.

  7. Natural killer cell cytotoxicity and antibody-dependent cellular cytotoxicity to herpes simplex virus-infected cells in human pregnancy.

    Science.gov (United States)

    Gonik, B; Loo, L S; West, S; Kohl, S

    1987-01-01

    Natural killer cell (NKC) cytotoxicity and antibody-dependent cellular cytotoxicity (ADCC) represent the ability of human leukocyte effector cells to destroy target cells in the absence and presence of antibody, respectively. Since these immune systems play a pivotal role in the body's primary lines of defense against a variety of pathogens including herpes simplex virus (HSV), a study was undertaken to evaluate the influence of pregnancy on these systems. Eleven uncomplicated gravidas were followed serially through each trimester and compared to 11 nonpregnant female controls. Mononuclear cells were acquired by Ficoll-Hypaque centrifugation of heparinized blood. Chang liver cells infected with HSV-I were utilized as target cells in a 51Cr release assay. Mean NKC values in the pregnant patients were uniformly lower than in the controls. No similar decreases in ADCC activity were observed in a comparison between the two study populations. These data support previous observations suggesting that pregnancy represents a relatively immunocompromised state. Differences apparently exist between NKC and ADCC effector cell populations with regard to the influence of pregnancy. Although these physiologic alterations in immunoregulation may help support the fetoplacental allograph, detrimental conditions may exist regarding susceptibility to various pathogens such as HSV.

  8. Interleukin-21 induces proliferation and modulates receptor expression and effector function in canine natural killer cells.

    Science.gov (United States)

    Shin, Dong-Jun; Lee, Soo-Hyeon; Park, Ji-Yun; Kim, Ju-Sun; Lee, Je-Jung; Suh, Guk-Hyun; Lee, Youn-Kyung; Cho, Duck; Kim, Sang-Ki

    2015-05-15

    Interleukin (IL)-21 is an important modulator of natural killer (NK) cell function. However, little is known about IL-21 function in canine NK cells because the phenotype of these cells remains undefined. In this study, we selectively expanded non-B and non-T large granular NK lymphocytes (CD3(-)CD21(-)CD5(-)CD4(-)TCRαβ(-)TCRγδ(-)) ex vivo from the peripheral blood mononuclear cells (PBMCs) of healthy dogs using a combination of IL-2, IL-15, and IL-21 in the presence of 100 Gy-irradiated K562 cells. We investigated the effects of varying the duration and timing of IL-21 treatment on stimulation of proliferation, expression of NK-related receptors, anti-tumor activity and production of interferon (IFN)-γ. The expanded NK cells in each treatment group became enlarged and highly granular after 21 days in culture. NK cells proliferated rapidly in response to activation by IL-21 for 3 weeks, and IL-21 was able to induce changes in the mRNA expression of NK cell-related receptors and enhance the effector function of NK cells in perforin- and granzyme-B-dependent manners. The duration, frequency and timing of IL-21 stimulation during culture affected the rate of proliferation, patterns of receptor expression, cytokine production, and anti-tumor activity. The optimal conditions for maximizing the IL-21-induced proliferation and effector function of NK cells in the presence of IL-2 and IL-15 were seen in cells treated with IL-21 for the first 7 days of culture but without any further IL-21 stimulation other than an additional 2-day treatment prior to harvesting on day 21. The results of this study suggest that synergistic interactions of IL-21 with IL-2 and IL-15 play an important role in the proliferation, receptor expression, and effector function of canine NK cells. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. Diversification of both KIR and NKG2 natural killer cell receptor genes in macaques - implications for highly complex MHC-dependent regulation of natural killer cells.

    Science.gov (United States)

    Walter, Lutz; Petersen, Beatrix

    2017-02-01

    The killer immunoglobulin-like receptors (KIR) as well as their MHC class I ligands display enormous genetic diversity and polymorphism in macaque species. Signals resulting from interaction between KIR or CD94/NKG2 receptors and their cognate MHC class I proteins essentially regulate the activity of natural killer (NK) cells. Macaque and human KIR share many features, such as clonal expression patterns, gene copy number variations, specificity for particular MHC class I allotypes, or epistasis between KIR and MHC class I genes that influence susceptibility and resistance to immunodeficiency virus infection. In this review article we also annotated publicly available rhesus macaque BAC clone sequences and provide the first description of the CD94-NKG2 genomic region. Besides the presence of genes that are orthologous to human NKG2A and NKG2F, this region contains three NKG2C paralogues. Hence, the genome of rhesus macaques contains moderately expanded and diversified NKG2 genes in addition to highly diversified KIR genes. The presence of two diversified NK cell receptor families in one species has not been described before and is expected to require a complex MHC-dependent regulation of NK cells. © 2016 John Wiley & Sons Ltd.

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

    Science.gov (United States)

    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 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 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.

  11. Natural killer cell-intrinsic type I IFN signaling controls Klebsiella pneumoniae growth during lung infection

    Science.gov (United States)

    Borroni, Martina; Kavirayani, Anoop; Przybyszewska, Kornelia N.; Ingram, Rebecca J.; Lienenklaus, Stefan

    2017-01-01

    Klebsiella pneumoniae is a significant cause of nosocomial pneumonia and an alarming pathogen owing to the recent isolation of multidrug resistant strains. Understanding of immune responses orchestrating K. pneumoniae clearance by the host is of utmost importance. Here we show that type I interferon (IFN) signaling protects against lung infection with K. pneumoniae by launching bacterial growth-controlling interactions between alveolar macrophages and natural killer (NK) cells. Type I IFNs are important but disparate and incompletely understood regulators of defense against bacterial infections. Type I IFN receptor 1 (Ifnar1)-deficient mice infected with K. pneumoniae failed to activate NK cell-derived IFN-γ production. IFN-γ was required for bactericidal action and the production of the NK cell response-amplifying IL-12 and CXCL10 by alveolar macrophages. Bacterial clearance and NK cell IFN-γ were rescued in Ifnar1-deficient hosts by Ifnar1-proficient NK cells. Consistently, type I IFN signaling in myeloid cells including alveolar macrophages, monocytes and neutrophils was dispensable for host defense and IFN-γ activation. The failure of Ifnar1-deficient hosts to initiate a defense-promoting crosstalk between alveolar macrophages and NK cell was circumvented by administration of exogenous IFN-γ which restored endogenous IFN-γ production and restricted bacterial growth. These data identify NK cell-intrinsic type I IFN signaling as essential driver of K. pneumoniae clearance, and reveal specific targets for future therapeutic exploitations. PMID:29112952

  12. Interleukin-17D Mediates Tumor Rejection through Recruitment of Natural Killer Cells

    Directory of Open Access Journals (Sweden)

    Timothy O’Sullivan

    2014-05-01

    Full Text Available The process of cancer immunoediting generates a repertoire of cancer cells that can persist in immune-competent hosts. In its most complex form, this process begins with the elimination of highly immunogenic unedited tumor cells followed by the escape of less immunogenic edited cells. Although edited tumors can release immunosuppressive factors, it is unknown whether unedited tumors produce cytokines that enhance antitumor function. Utilizing gene microarray analysis, we found the cytokine interleukin 17D (IL-17D was highly expressed in certain unedited tumors but not in edited mouse tumor cell lines. Moreover, forced expression of IL-17D in edited tumor cells induced rejection by stimulating MCP-1 production from tumor endothelial cells, leading to the recruitment of natural killer (NK cells. NK cells promoted M1 macrophage development and adaptive immune responses. IL-17D expression was also decreased in certain high-grade and metastatic human tumors, suggesting that it can be targeted for tumor immune therapy.

  13. Cytotoxicity Study of Cyclopentapeptide Analogues of Marine Natural Product Galaxamide towards Human Breast Cancer Cells

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    Jignesh Lunagariya

    2017-01-01

    Full Text Available Herein, we report the cytotoxicity of cyclopentapeptide analogues of marine natural product galaxamide towards breast carcinoma cells and the underlying mechanisms. We examined the effect of the novel galaxamide analogues on cancer cell proliferation by MTT assay and also further examined the most active compound for morphological changes using Hoechst33342 staining technique, induction of apoptosis, cell cycle phases, mitochondrial membrane potential (MMP, and reactive oxygen species (ROS generation using flow cytometry in human breast cancer MCF-7 cells in vitro. Galaxamide and its analogues effectively induced toxicity in human hepatocellular carcinoma HepG2, human breast carcinoma MCF-7, human epitheloid cervix carcinoma HeLa, and human breast carcinoma MB-MDA-231 cell lines. Amongst them, compound 3 exhibited excellent toxicity towards MCF-7 cells. This galaxamide analogue significantly induced apoptosis in a dose-dependent manner in MCF-7 cells involves cell cycle arrest in the G1 phase, a reduction of MMP, and a marked increase in generation of ROS. Particularly, compound 3 of galaxamide analogues might be a potential candidate for the treatment of breast cancer.

  14. Chimeric Antigen Receptor Expressing Natural Killer Cells for the Immunotherapy of Cancer

    Directory of Open Access Journals (Sweden)

    Rohtesh S. Mehta

    2018-02-01

    Full Text Available Adoptive cell therapy has emerged as a powerful treatment for advanced cancers resistant to conventional agents. Most notable are the remarkable responses seen in patients receiving autologous CD19-redirected chimeric antigen receptor (CAR T cells for the treatment of B lymphoid malignancies; however, the generation of autologous products for each patient is logistically cumbersome and has restricted widespread clinical use. A banked allogeneic product has the potential to overcome these limitations, yet allogeneic T-cells (even if human leukocyte antigen-matched carry a major risk of graft-versus-host disease (GVHD. Natural killer (NK cells are bone marrow-derived innate lymphocytes that can eliminate tumors directly, with their activity governed by the integration of signals from activating and inhibitory receptors and from cytokines including IL-15, IL-12, and IL-18. NK cells do not cause GVHD or other alloimmune or autoimmune toxicities and thus, can provide a potential source of allogeneic “off-the-shelf” cellular therapy, mediating major anti-tumor effects without inducing potentially lethal alloreactivity such as GVHD. Given the multiple unique advantages of NK cells, researchers are now exploring the use of CAR-engineered NK cells for the treatment of various hematological and non-hematological malignancies. Herein, we review preclinical data on the development of CAR-NK cells, advantages, disadvantages, and current obstacles to their clinical use.

  15. Resveratrol mediated cell death in cigarette smoke transformed breast epithelial cells is through induction of p21Waf1/Cip1 and inhibition of long patch base excision repair pathway

    Energy Technology Data Exchange (ETDEWEB)

    Mohapatra, Purusottam; Satapathy, Shakti Ranjan; Das, Dipon; Siddharth, Sumit [Cancer Biology Division, KIIT School of Biotechnology, KIIT University, Campus-11, Patia, Bhubaneswar, Orissa 751024 (India); Choudhuri, Tathagata [Institute of Life Sciences, Nalco Square, Bhubaneswar, Orissa 751023 (India); Department of Biotechnology, Visva Bharati University, Santiniketan, West Bengal (India); Kundu, Chanakya Nath, E-mail: cnkundu@gmail.com [Cancer Biology Division, KIIT School of Biotechnology, KIIT University, Campus-11, Patia, Bhubaneswar, Orissa 751024 (India)

    2014-03-15

    Cigarette smoking is a key factor for the development and progression of different cancers including mammary tumor in women. Resveratrol (Res) is a promising natural chemotherapeutic agent that regulates many cellular targets including p21, a cip/kip family of cyclin kinase inhibitors involved in DNA damage-induced cell cycle arrest and blocking of DNA replication and repair. We have recently shown that cigarette smoke condensate (CSC) prepared from commercially available Indian cigarette can cause neoplastic transformation of normal breast epithelial MCF-10A cell. Here we studied the mechanism of Res mediated apoptosis in CSC transformed (MCF-10A-Tr) cells in vitro and in vivo. Res mediated apoptosis in MCF-10A-Tr cells was a p21 dependent event. It increased the p21 protein expression in MCF-10A-Tr cells and MCF-10A-Tr cells-mediated tumors in xenograft mice. Res treatment reduced the tumor size(s) and expression of anti-apoptotic proteins (e.g. PI3K, AKT, NFκB) in solid tumor. The expressions of cell cycle regulatory (Cyclins, CDC-2, CDC-6, etc.), BER associated (Pol-β, Pol-δ, Pol-ε, Pol-η, RPA, Fen-1, DNA-Ligase-I, etc.) proteins and LP-BER activity decreased in MCF-10A-Tr cells but remain significantly unaltered in isogenic p21 null MCF-10A-Tr cells after Res treatment. Interestingly, no significant changes were noted in SP-BER activity in both the cell lines after Res exposure. Finally, it was observed that increased p21 blocks the LP-BER in MCF-10A-Tr cells by increasing its interaction with PCNA via competing with Fen-1 after Res treatment. Thus, Res caused apoptosis in CSC-induced cancer cells by reduction of LP-BER activity and this phenomenon largely depends on p21. - Highlights: • Resveratrol (Res) caused reduction of MCF-10A-Tr cell growth by inducing apoptosis. • Res caused cell cycle arrest and DNA damage in p21 dependent manner. • Res mediated LP-BER reduction in MCF-10A-Tr cells was a p21 dependent phenomenon. • Res inhibits BER and PI

  16. Resveratrol mediated cell death in cigarette smoke transformed breast epithelial cells is through induction of p21Waf1/Cip1 and inhibition of long patch base excision repair pathway

    International Nuclear Information System (INIS)

    Mohapatra, Purusottam; Satapathy, Shakti Ranjan; Das, Dipon; Siddharth, Sumit; Choudhuri, Tathagata; Kundu, Chanakya Nath

    2014-01-01

    Cigarette smoking is a key factor for the development and progression of different cancers including mammary tumor in women. Resveratrol (Res) is a promising natural chemotherapeutic agent that regulates many cellular targets including p21, a cip/kip family of cyclin kinase inhibitors involved in DNA damage-induced cell cycle arrest and blocking of DNA replication and repair. We have recently shown that cigarette smoke condensate (CSC) prepared from commercially available Indian cigarette can cause neoplastic transformation of normal breast epithelial MCF-10A cell. Here we studied the mechanism of Res mediated apoptosis in CSC transformed (MCF-10A-Tr) cells in vitro and in vivo. Res mediated apoptosis in MCF-10A-Tr cells was a p21 dependent event. It increased the p21 protein expression in MCF-10A-Tr cells and MCF-10A-Tr cells-mediated tumors in xenograft mice. Res treatment reduced the tumor size(s) and expression of anti-apoptotic proteins (e.g. PI3K, AKT, NFκB) in solid tumor. The expressions of cell cycle regulatory (Cyclins, CDC-2, CDC-6, etc.), BER associated (Pol-β, Pol-δ, Pol-ε, Pol-η, RPA, Fen-1, DNA-Ligase-I, etc.) proteins and LP-BER activity decreased in MCF-10A-Tr cells but remain significantly unaltered in isogenic p21 null MCF-10A-Tr cells after Res treatment. Interestingly, no significant changes were noted in SP-BER activity in both the cell lines after Res exposure. Finally, it was observed that increased p21 blocks the LP-BER in MCF-10A-Tr cells by increasing its interaction with PCNA via competing with Fen-1 after Res treatment. Thus, Res caused apoptosis in CSC-induced cancer cells by reduction of LP-BER activity and this phenomenon largely depends on p21. - Highlights: • Resveratrol (Res) caused reduction of MCF-10A-Tr cell growth by inducing apoptosis. • Res caused cell cycle arrest and DNA damage in p21 dependent manner. • Res mediated LP-BER reduction in MCF-10A-Tr cells was a p21 dependent phenomenon. • Res inhibits BER and PI

  17. Angiotensin II activates MAP kinase and NF-kappaB through angiotensin II type I receptor in human pancreatic cancer cells.

    Science.gov (United States)

    Amaya, Koji; Ohta, Tetsuo; Kitagawa, Hirohisa; Kayahara, Masato; Takamura, Hiroyuki; Fujimura, Takashi; Nishimura, Gen-Ichi; Shimizu, Koichi; Miwa, Koichi

    2004-10-01

    Pancreatic ductal cancer has higher angiotensin II concentrations compared with normal pancreas or other solid tumors. This study examined angiotensin II type 1 (AT1) receptor expression and the role of angiotensin II in proliferation and survival of human pancreatic cancer cells. All three pancreatic cancer cell lines studied, from well to poorly-differentiated types, HPAF-II, AsPC-1, and Panc-1, showed strong expression of AT1 receptor. In contrast, HT-29 human colon cancer cells showed extremely weak expression. Angiotensin II stimulated the growth of pancreatic cancer cells through MAP kinase activation but had no significant effect on proliferation of HT-29 colon cancer cells. In addition, angiotensin II significantly prevented cisplatin (CDDP)-induced apoptosis through NF-kappaB activation and the subsequent production of anti-apoptotic molecules, including survivin and Bcl-XL, in pancreatic cancer cells. These findings suggest that angiotensin II plays a role in the growth and chemoresistance of AT1-positive pancreatic cancer cells through its action as a potent mitogen and anti-apoptotic molecule.

  18. Circumvention of Mcl-1-dependent drug resistance by simultaneous Chk1 and MEK1/2 inhibition in human multiple myeloma cells.

    Directory of Open Access Journals (Sweden)

    Xin-Yan Pei

    Full Text Available The anti-apoptotic protein Mcl-1 plays a major role in multiple myeloma (MM cell survival as well as bortezomib- and microenvironmental forms of drug resistance in this disease. Consequently, there is a critical need for strategies capable of targeting Mcl-1-dependent drug resistance in MM. The present results indicate that a regimen combining Chk1 with MEK1/2 inhibitors effectively kills cells displaying multiple forms of drug resistance stemming from Mcl-1 up-regulation in association with direct transcriptional Mcl-1 down-regulation and indirect disabling of Mcl-1 anti-apoptotic function through Bim up-regulation and increased Bim/Mcl-1 binding. These actions release Bak from Mcl-1, accompanied by Bak/Bax activation. Analogous events were observed in both drug-naïve and acquired bortezomib-resistant MM cells displaying increased Mcl-1 but diminished Bim expression, or cells ectopically expressing Mcl-1. Moreover, concomitant Chk1 and MEK1/2 inhibition blocked Mcl-1 up-regulation induced by IL-6/IGF-1 or co-culture with stromal cells, effectively overcoming microenvironment-related drug resistance. Finally, this regimen down-regulated Mcl-1 and robustly killed primary CD138+ MM cells, but not normal hematopoietic cells. Together, these findings provide novel evidence that this targeted combination strategy could be effective in the setting of multiple forms of Mcl-1-related drug resistance in MM.

  19. Circumvention of Mcl-1-dependent drug resistance by simultaneous Chk1 and MEK1/2 inhibition in human multiple myeloma cells.

    Science.gov (United States)

    Pei, Xin-Yan; Dai, Yun; Felthousen, Jessica; Chen, Shuang; Takabatake, Yukie; Zhou, Liang; Youssefian, Leena E; Sanderson, Michael W; Bodie, Wesley W; Kramer, Lora B; Orlowski, Robert Z; Grant, Steven

    2014-01-01

    The anti-apoptotic protein Mcl-1 plays a major role in multiple myeloma (MM) cell survival as well as bortezomib- and microenvironmental forms of drug resistance in this disease. Consequently, there is a critical need for strategies capable of targeting Mcl-1-dependent drug resistance in MM. The present results indicate that a regimen combining Chk1 with MEK1/2 inhibitors effectively kills cells displaying multiple forms of drug resistance stemming from Mcl-1 up-regulation in association with direct transcriptional Mcl-1 down-regulation and indirect disabling of Mcl-1 anti-apoptotic function through Bim up-regulation and increased Bim/Mcl-1 binding. These actions release Bak from Mcl-1, accompanied by Bak/Bax activation. Analogous events were observed in both drug-naïve and acquired bortezomib-resistant MM cells displaying increased Mcl-1 but diminished Bim expression, or cells ectopically expressing Mcl-1. Moreover, concomitant Chk1 and MEK1/2 inhibition blocked Mcl-1 up-regulation induced by IL-6/IGF-1 or co-culture with stromal cells, effectively overcoming microenvironment-related drug resistance. Finally, this regimen down-regulated Mcl-1 and robustly killed primary CD138+ MM cells, but not normal hematopoietic cells. Together, these findings provide novel evidence that this targeted combination strategy could be effective in the setting of multiple forms of Mcl-1-related drug resistance in MM.

  20. Monocyte-Derived Signals Activate Human Natural Killer Cells in Response to Leishmania Parasites

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    Helena Messlinger

    2018-01-01

    Full Text Available Activated natural killer (NK cells release interferon (IFN-γ, which is crucial for the control of intracellular pathogens such as Leishmania. In contrast to experimental murine leishmaniasis, the human NK cell response to Leishmania is still poorly characterized. Here, we investigated the interaction of human blood NK cells with promastigotes of different Leishmania species (Leishmania major, Leishmania mexicana, Leishmania infantum, and Leishmania donovani. When peripheral blood mononuclear cells or purified NK cells and monocytes (all derived from healthy blood donors from Germany without a history of leishmaniasis were exposed to promastigotes, NK cells showed increased surface expression of the activation marker CD69. The extent of this effect varied depending on the Leishmania species; differences between dermotropic and viscerotropic L. infantum strains were not observed. Upregulation of CD69 required direct contact between monocytes and Leishmania and was partly inhibitable by anti-interleukin (IL-18. Unexpectedly, IL-18 was undetectable in most of the supernatants (SNs of monocyte/parasite cocultures. Confocal fluorescence microscopy of non-permeabilized cells revealed that Leishmania-infected monocytes trans-presented IL-18 to NK cells. Native, but not heat-treated SNs of monocyte/Leishmania cocultures also induced CD69 on NK cells, indicating the involvement of a soluble heat-labile factor other than IL-18. A role for the NK cell-activating cytokines IL-1β, IL-2, IL-12, IL-15, IL-21, and IFN-α/β was excluded. The increase of CD69 was not paralleled by NK cell IFN-γ production or enhanced cytotoxicity. However, prior exposure of NK cells to Leishmania parasites synergistically increased their IFN-γ release in response to IL-12, which was dependent on endogenous IL-18. CD1c+ dendritic cells were identified as possible source of Leishmania-induced IL-12. Finally, we observed that direct contact between Leishmania and NK cells

  1. Phosphoinositide-3-Kinase Signaling in Human Natural Killer Cells: New Insights from Primary Immunodeficiency

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    Emily M. Mace

    2018-03-01

    Full Text Available Human natural killer (NK cells play a critical role in the control of viral infections and malignancy. Their importance in human health and disease is illustrated by severe viral infections in patients with primary immunodeficiencies that affect NK cell function and/or development. The recent identification of patients with phosphoinositide-3-kinase (PI3K-signaling pathway mutations that can cause primary immunodeficiency provides valuable insight into the role that PI3K signaling plays in human NK cell maturation and lytic function. There is a rich literature that demonstrates a requirement for PI3K in multiple key aspects of NK cell biology, including development/maturation, homing, priming, and function. Here, I briefly review these previous studies and place them in context with recent findings from the study of primary immunodeficiency patients, particularly those with hyperactivating mutations in PI3Kδ signaling.

  2. Inhibition of natural killer cell activity by eicosapentaenoic acid in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, N.; Sugiyama, E.; Hamazaki, T.; Yano, S.

    1988-01-15

    To examine the effects of in vivo eicosapentaenoic acid (EPA) on natural killer (NK) cell activity, C3H/He mice each received a single intraperitoneal bolus of an emulsion of trieicosapentaenoyl-glycerol (EPA-TG). Spleen cells were tested for NK activity using /sup 51/Chromium-release assays against YAC-1 target cells. Forty eight hours after injection, NK activity was inhibited in a dose-dependent manner. EPA-TG emulsion also inhibited the NK activity of NK-enriched effector cells. Decreased cytotoxicity was first noted 24 hr after injection; it resumed the baseline by 7 days. The addition of EPA-TG emulsion to a cytotoxicity assay system resulted in moderate depression of NK activity. These results demonstrate that EPA has significant immunomodulatory effects on NK activity.

  3. Grasping the nature of the cell interior: from Physiological Chemistry to Chemical Biology.

    Science.gov (United States)

    Kyne, Ciara; Crowley, Peter B

    2016-08-01

    Current models of the cell interior emphasise its crowded, chemically complex and dynamically organised structure. Although the chemical composition of cells is known, the cooperative intermolecular interactions that govern cell ultrastructure are poorly understood. A major goal of biochemistry is to capture these myriad interactions in vivo. We consider the landmark discoveries that have shaped this objective, starting from the vitalist framework established by early natural philosophers. Through this historical revisionism, we extract important lessons for the bioinspired chemists of today. Scientific specialisation tends to insulate seminal ideas and hamper the unification of paradigms across biology. Therefore, we call for interdisciplinary collaboration in grappling with the complex cell interior. Recent successes in integrative structural biology and chemical biology demonstrate the power of hybrid approaches. The future roles of the (bio)chemist and model systems are also discussed as starting points for in vivo explorations. © 2016 Federation of European Biochemical Societies.

  4. Activation mechanisms of invariant natural killer T cells (iNKTs

    Directory of Open Access Journals (Sweden)

    Baena, Andrés

    2016-01-01

    Full Text Available A great amount of knowledge on natural killer T cells (iNKTs is now available, but a consensus about their activation mechanisms has not been reached. These cells recognize different glycolipid antigens through the CD1d molecule. Such antigens may be endogenous, derived from bacteria (foreign and synthetic, the latter have been developed for clinical applications. There exists much interest in understanding how these different glycolipid compounds induce different types of polarization, but it has been difficult to reach a consensus due to the fact that responses depend on different factors such as: the nature of the molecule, the internalization process and the presentation of the glycolipids. Moreover, activation of iNKT cells is determined by the type and state of the antigen presenting cell, the co-stimulatory molecules, the transactivation mechanisms and the location of the glycolipid-CD1d complexes on the plasma membrane, such as the lipid rafts. This review explores the evidence about the factors that affect activation of iNKT cells in order to understand their immune-modulatory potential.

  5. Natural Killer-like B Cells Prime Innate Lymphocytes against Microbial Infection.

    Science.gov (United States)

    Wang, Shuo; Xia, Pengyan; Chen, Yi; Huang, Guanling; Xiong, Zhen; Liu, Jing; Li, Chong; Ye, Buqing; Du, Ying; Fan, Zusen

    2016-07-19

    Natural killer (NK) cells and non-cytotoxic interferon-γ (IFN-γ)-producing group I innate lymphoid cells (ILC1s) produce large amounts of IFN-γ and cause activation of innate and adaptive immunity. However, how NKs and ILC1s are primed during infection remains elusive. Here we have shown that a lymphocyte subpopulation natural killer-like B (NKB) cells existed in spleen and mesenteric lymph nodes (MLNs). NKBs had unique features that differed from T and B cells, and produced interleukin-18 (IL-18) and IL-12 at an early phase of infection. NKB cells played a critical role in eradication of microbial infection via secretion of IL-18 and IL-12. Moreover, IL-18 deficiency abrogated the antibacterial effect of NKBs. Upon bacterial challenge, NKB precursors (NKBPs) rapidly differentiated to NKBs that activated NKs and ILC1s against microbial infection. Our findings suggest that NKBs might be exploited to develop effective therapies for treatment of infectious diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Dye-sensitized solar cells using natural dyes as sensitizers from Malaysia local fruit `Buah Mertajam'

    Science.gov (United States)

    Hambali, N. A. M. Ahmad; Roshidah, N.; Hashim, M. Norhafiz; Mohamad, I. S.; Saad, N. Hidayah; Norizan, M. N.

    2015-05-01

    We experimentally demonstrate the high conversion efficiency, low cost, green technology and easy to fabricate dye-sensitized solar cells (DSSCs) using natural anthocyanin dyes as sensitizers. The DSSCs was fabricated by using natural anthocyanin dyes which were extracted from different parts of the plants inclusive `Buah Mertajam', `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. The natural anthocyanin dyes that found in flower, leaves and fruits were extracted by the simple procedures. This anthocyanin dye is used to replace the expensive chemical synthetic dyes due to its ability to effectively attach into the surface of Titanium dioxide (TiO2). A natural anthocyanin dyes molecule adsorbs to each particle of the TiO2 and acts as the absorber of the visible light. A natural anthocyanin dye from Buah Mertajam shows the best performance with the conversion efficiency of 5.948% and fill factor of 0.708 followed by natural anthocyanin dyes from `Buah Keriang Dot', `Bunga Geti', Hibiscus, Red Spinach and Henna. Buah Mertajam or scientifically known as eriglossum rubiginosum is a local Malaysia fruit.

  7. Potentiation of Natural Killer Cells for Cancer Immunotherapy: A Review of Literature

    Directory of Open Access Journals (Sweden)

    Lacy E. Lowry

    2017-09-01

    Full Text Available It is widely acknowledged that the human immune system plays a crucial role in preventing the formation and progression of innumerable types of cancer (1. The mechanisms by which this occurs are numerous, including contributions from both the innate and adaptive immune systems. As such, immunotherapy has long been believed to be an auspicious solution in the treatment of malignancy (2. Recent research has highlighted the promise of natural killer (NK cells as a more directed immunotherapy approach. This paper will focus on the methods of potentiation of NK cells for their use in cancer therapy.

  8. Solid Lipid Curcumin Particles Induce More DNA Fragmentation and Cell Death in Cultured Human Glioblastoma Cells than Does Natural Curcumin

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    Panchanan Maiti

    2017-01-01

    Full Text Available Despite recent advancements in cancer therapies, glioblastoma multiforme (GBM remains largely incurable. Curcumin (Cur, a natural polyphenol, has potent anticancer effects against several malignancies, including metastatic brain tumors. However, its limited bioavailability reduces its efficiency for treating GBM. Recently, we have shown that solid lipid Cur particles (SLCPs have greater bioavailability and brain tissue penetration. The present study compares the efficiency of cell death by Cur and/or SLCPs in cultured GBM cells derived from human (U-87MG and mouse (GL261 tissues. Several cell viability and cell death assays and marker proteins (MTT assay, annexin-V staining, TUNEL staining, comet assay, DNA gel electrophoresis, and Western blot were investigated following the treatment of Cur and/or SLCP (25 μM for 24–72 h. Relative to Cur, the use of SLCP increased cell death and DNA fragmentation, produced longer DNA tails, and induced more fragmented nuclear lobes. In addition, cultured GBM cells had increased levels of caspase-3, Bax, and p53, with decreases in Bcl2, c-Myc, and both total Akt, as well as phosphorylated Akt, when SLCP, rather Cur, was used. Our in vitro work suggests that the use of SLCP may be a promising strategy for reversing or preventing GBM growth, as compared to using Cur.

  9. Apoptosis in HEp-2 cells infected with Ureaplasma diversum

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    Aline Teixeira Amorim

    2014-01-01

    Full Text Available BACKGROUND: Bacterial pathogens have many strategies for infecting and persisting in host cells. Adhesion, invasion and intracellular life are important features in the biology of mollicutes. The intracellular location ofUreaplasma diversum may trigger disturbances in the host cell. This includes activation or inhibition of pro and anti-apoptotic factors, which facilitate the development of host damage. The aim of the present study was to associate U. diversum infection in HEp-2 cells and apoptosis induction. Cells were infected for 72hs with four U. diversum clinical isolates and an ATCC strain. The U. diversuminvasion was analyzed by Confocal Laser Scanning Microscopy and gentamicin invasion assay. The apoptosis was evaluated using pro-apoptotic and anti-apoptotic gene expression, and FITC Annexin V/Dead Cell Apoptosis Kit. RESULTS: The number of internalized ureaplasma in HEp-2 cells increased significantly throughout the infection. The flow cytometry analysis with fluorochromes to detect membrane depolarization and gene expression for caspase 2, 3 and 9 increased in infected cells after 24 hours. However, after 72 hours a considerable decrease of apoptotic cells was observed. CONCLUSIONS: The data suggests that apoptosis may be initially induced by some isolates in association with HEp-2 cells, but over time, there was no evidence of apoptosis in the presence of ureaplasma and HEp-2 cells. The initial increase and then decrease in apoptosis could be related to bacterial pathogen-associated molecular pattern (PAMPS. Moreover, the isolates of U. diversum presented differences in the studied parameters for apoptosis. It was also observed that the amount of microorganisms was not proportional to the induction of apoptosis in HEp-2 cells.

  10. Apoptosis in HEp-2 cells infected with Ureaplasma diversum.

    Science.gov (United States)

    Amorim, Aline Teixeira; Marques, Lucas Miranda; Santos, Angelita Maria Oliveira Gusmão; Martins, Hellen Braga; Barbosa, Maysa Santos; Rezende, Izadora Souza; Andrade, Ewerton Ferraz; Campos, Guilherme Barreto; Lobão, Tássia Neves; Cortez, Beatriz Araujo; Monezi, Telma Alvez; Machado-Santelli, Glaucia Maria; Timenetsky, Jorge

    2014-09-04

    Bacterial pathogens have many strategies for infecting and persisting in host cells. Adhesion, invasion and intracellular life are important features in the biology of mollicutes. The intracellular location of Ureaplasma diversum may trigger disturbances in the host cell. This includes activation or inhibition of pro and anti-apoptotic factors, which facilitate the development of host damage. The aim of the present study was to associate U. diversum infection in HEp-2 cells and apoptosis induction. Cells were infected for 72hs with four U. diversum clinical isolates and an ATCC strain. The U. diversum invasion was analyzed by Confocal Laser Scanning Microscopy and gentamicin invasion assay. The apoptosis was evaluated using pro-apoptotic and anti-apoptotic gene expression, and FITC Annexin V/Dead Cell Apoptosis Kit. The number of internalized ureaplasma in HEp-2 cells increased significantly throughout the infection. The flow cytometry analysis with fluorochromes to detect membrane depolarization and gene expression for caspase 2, 3 and 9 increased in infected cells after 24 hours. However, after 72 hours a considerable decrease of apoptotic cells was observed. The data suggests that apoptosis may be initially induced by some isolates in association with HEp-2 cells, but over time, there was no evidence of apoptosis in the presence of ureaplasma and HEp-2 cells. The initial increase and then decrease in apoptosis could be related to bacterial pathogen-associated molecular pattern (PAMPS). Moreover, the isolates of U. diversum presented differences in the studied parameters for apoptosis. It was also observed that the amount of microorganisms was not proportional to the induction of apoptosis in HEp-2 cells.

  11. Postoperative infection and natural killer cell function following blood transfusion in patients undergoing elective colorectal surgery

    DEFF Research Database (Denmark)

    Jensen, L S; Andersen, A J; Christiansen, P M

    1992-01-01

    The frequency of infection in 197 patients undergoing elective colorectal surgery and having either no blood transfusion, transfusion with whole blood, or filtered blood free from leucocytes and platelets was investigated in a prospective randomized trial. Natural killer cell function was measured...... before operation and 3, 7 and 30 days after surgery in 60 consecutive patients. Of the patients 104 required blood transfusion; 48 received filtered blood and 56 underwent whole blood transfusion. Postoperative infections developed in 13 patients transfused with whole blood (23 per cent, 95 per cent...... confidence interval 13-32 per cent), in one patient transfused with blood free from leucocytes and platelets (2 per cent, 95 per cent confidence interval 0.05-11 per cent) and in two non-transfused patients (2 per cent, 95 per cent confidence interval 0.3-8 per cent) (P less than 0.01). Natural killer cell...

  12. Pentoxifylline sensitizes human cervical tumor cells to cisplatin-induced apoptosis by suppressing NF-kappa B and decreased cell senescence

    International Nuclear Information System (INIS)

    Hernandez-Flores, Georgina; Bravo-Cuellar, Alejandro; Ortiz-Lazareno, Pablo C; Lerma-Diaz, Jose Manuel; Dominguez-Rodriguez, Jorge R; Jave-Suarez, Luis F; Aguilar-Lemarroy, Adriana del C; Celis-Carrillo, Ruth de; Toro-Arreola, Susana del; Castellanos-Esparza, Yessica C

    2011-01-01

    Worldwide, cervical cancer is the second most common causes of cancer in women and represents an important mortality rate. Cisplatin (CIS) is a very important antitumoral agent and can lead tumor cells toward two important cellular states: apoptosis and senescence. In some types of cancers pentoxifylline (PTX) sensitizes these cells to the toxic action of chemotherapeutics drugs such as adriamycin, inducing apoptosis. In the present work, we studied in vitro whether PTX alone or in combination with CIS induces apoptosis and/or senescence in cervix cancer HeLa and SiHa cell lines infected with HPV types 16 and 18, respectively, as well as in immortalized keratinocytyes HaCaT cells. HeLa (HPV 18+), SiHa (HPV 16+) cervix cancer cells and non-tumorigenic immortalized HaCaT cells (control) were treated with PTX, CIS or both. The cellular toxicity and survival fraction of PTX and CIS were determinate by WST-1 and clonogenic assays respectively. Apoptosis, caspase activation and phosphorylation of ERK1/2, p38, p65 (NF-κB), Bcl-2 and Bcl-XL anti-apoptotic proteins were determinated by flow cytometry. Senescence by microscopy. Phosphorylation of IκBα and IκB total were measured by ELISA. Pro-apoptotic, anti-apoptotic and senescence genes, as well as HPV-E6/7 mRNA expression, were detected by RT-PCR. Our results show that after 24 hours of incubation PTX per se is toxic for cancer cells affecting cell viability and inducing apoptosis. The toxicity in HaCaT cells was minimal. CIS induces apoptosis in HeLa and SiHa cells and its effect was significantly increases when the cells were treated with PTX + CIS. In all studies there was a direct correlation with levels of caspases (-3, -6, -7, -9 and -8) activity and apoptosis. CIS induces important levels of senescence and phosphorylation of ERK1/2, p38, p65/RELA, and IκBα, and decreased the expression of anti-apoptotic protein Bcl-XL. Surprisingly these levels were significantly reduced by PTX in tumor cells, and at the same

  13. Natural history of β-cell adaptation and failure in type 2 diabetes

    Science.gov (United States)

    Alejandro, Emilyn U.; Gregg, Brigid; Blandino-Rosano, Manuel; Cras-Méneur, Corentin; Bernal-Mizrachi, Ernesto

    2014-01-01

    Type 2 diabetes mellitus (T2D) is a complex disease characterized by β-cell failure in the setting of insulin resistance. The current evidence suggests that genetic predisposition, and environmental factors can impair the capacity of the β-cells to respond to insulin resistance and ultimately lead to their failure. However, genetic studies have demonstrated that known variants account for less than 10% of the overall estimated T2D risk, suggesting that additional unidentified factors contribute to susceptibility of this disease. In this review, we will discuss the different stages that contribute to the development of β-cell failure in T2D. We divide the natural history of this process in three major stages: susceptibility, β-cell adaptation and β-cell failure and provide an overview of the molecular mechanisms involved. Further research into mechanisms will reveal key modulators of β-cell failure and thus identify possible novel therapeutic targets and potential interventions to protect against β-cell failure. PMID:25542976

  14. Natural Killer Cell Function and Dysfunction in Hepatitis C Virus Infection

    Directory of Open Access Journals (Sweden)

    Kayla A. Holder

    2014-01-01

    Full Text Available 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.

  15. Impact of blood processing variations on Natural Killer cell frequency, activation, chemokine receptor expression and function

    Science.gov (United States)

    Naranbhai, Vivek; Bartman, Pat; Ndlovu, Dudu; Ramkalawon, Pamela; Ndung’u, Thumbi; Wilson, Douglas; Altfeld, Marcus; Carr, William H

    2011-01-01

    Understanding the role of natural killer (NK) cells in human disease pathogenesis is crucial and necessitates study of patient samples directly ex vivo. Manipulation of whole blood by density gradient centrifugation or delays in sample processing due to shipping, however, may lead to artifactual changes in immune response measures. Here, we assessed the impact of density gradient centrifugation and delayed processing of both whole blood and peripheral blood mononuclear cells (PBMC) at multiple timepoints (2–24 hrs) on flow cytometric measures of NK cell frequency, activation status, chemokine receptor expression, and effector functions. We found that density gradient centrifugation activated NK cells and modified chemokine receptor expression. Delays in processing beyond 8 hours activated NK cells in PBMC but not in whole blood. Likewise, processing delays decreased chemokine receptor (CCR4 and CCR7) expression in both PBMC and whole blood. Finally, delays in processing PBMC were associated with a decreased ability of NK cells to degranulate (as measured by CD107a expression) or secrete cytokines (IFN-γ and TNF-α). In summary, our findings suggest that density gradient centrifugation and delayed processing of PBMC can alter measures of clinically relevant NK cell characteristics including effector functions; and therefore should be taken into account in designing clinical research studies. PMID:21255578

  16. Naturally occurring glucagon-like peptide-2 (GLP-2) receptors in human intestinal cell lines.

    Science.gov (United States)

    Sams, Anette; Hastrup, Sven; Andersen, Marie; Thim, Lars

    2006-02-17

    Although clinical trials with GLP-2 receptor agonists are currently ongoing, the mechanisms behind GLP-2-induced intestinal epithelial growth remain to be understood. To approach the GLP-2 mechanism of action this study aimed to identify intestinal cell lines endogenously expressing the GLP-2 receptor. Here we report the first identification of a cell line endogenously expressing functional GLP-2 receptors. The human intestinal epithelial cell line, FHC, expressed GLP-2 receptor encoding mRNA (RT-PCR) and GLP-2 receptor protein (Western blot). In cultured FHC cells, GLP-2 induced concentration dependent cAMP accumulation (pEC(50)=9.7+/-0.04 (mean+/-S.E.M., n=4)). In addition, a naturally occurring human intestinal fibroblast cell line, 18Co, endogenously expressing GLP-2 receptor encoding mRNA (RT-PCR) and protein (Western blot) was identified. No receptor functionality (binding or G-protein signalling) could be demonstrated in 18Co cells. The identified gut-relevant cell lines provide tools for future clarification of the mechanisms underlying GLP-2-induced epithelial growth.

  17. Natural killer cell activities of synbiotic Lactobacillus casei ssp. casei in conjunction with dextran.

    Science.gov (United States)

    Ogawa, T; Asai, Y; Tamai, R; Makimura, Y; Sakamoto, H; Hashikawa, S; Yasuda, K

    2006-01-01

    We have reported previously that Lactobacillus casei ssp. casei, together with specific substrate dextran, exhibited an adjuvant effect of stimulating humoral immune responses against bovine serum albumin (BSA) as a model antigen in BALB/c mice. In the present study, among the Lactobacillus species tested, L. casei ssp. casei with dextran significantly elevated the natural killer (NK) cell activities in spleen mononuclear cells from BALB/c mice in comparison to L. casei ssp. casei alone or other Lactobacillus species with or without dextran. Oral administration of L. casei ssp. casei together with dextran also resulted in a significant increase of NK cell activities in healthy human volunteers. Further, L. casei ssp. casei induced significant production of interleukin (IL)-12 in human peripheral blood mononuclear cells and IL-15 mRNA expression in the human intestinal epithelial cell line Caco-2. L. casei ssp. casei with dextran in food also significantly elevated the survival rate of BALB/c mice bearing Meth-A cells. Taken together, these results demonstrate that dietary synbiotic supplementation which is a combination of the L. casei ssp. casei used as a probiotic together with the dextran, a specific substrate as a prebiotic, efficiently elicits murine and human NK cell activities.

  18. Decreased Cytotoxicity of Peripheral and Peritoneal Natural Killer Cell in Endometriosis.

    Science.gov (United States)

    Jeung, InCheul; Cheon, Keunyoung; Kim, Mee-Ran

    2016-01-01

    Endometriosis causes significant chronic pelvic pain, dysmenorrhea, and infertility and affects 10% of all women. In endometriosis, ectopic endometrium surviving after retrograde menstruation exhibits an abnormal immune response characterized by increased levels of activated macrophages and inflammatory cytokines. Particularly, dysfunctional natural killer (NK) cells play an important role in the pathogenesis of the disease by either facilitating or inhibiting the survival, implantation, and proliferation of endometrial cells. NK cells in the peritoneum