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- NK cells (23)
- Dibutyltin (6)
- Lytic function (6)
- PBMCs (6)
- Hexabromocyclododecane (5)
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- Pentachlorophenol (5)
- Tributyltin (5)
- Binding function (4)
- CD16 (4)
- CD56 (4)
- Granulocytes (4)
- Tetrabromobisphenol A (4)
- ATP (3)
- Dichlorodiphenyltrichloroethane (3)
- Interleukin 1 beta (3)
- Interleukin 1β (3)
- Interleukin 6 (3)
- MAPK (3)
- MD-PBMCs (3)
- P44/42 (3)
- ATP levels (2)
- Butyltin (2)
- DDT (2)
- Glutathione (2)
- Immune cells (2)
- Interferon gamma (2)
- MAP kinases (2)
- MRNA (2)
- Natural Killer Cell (2)
- PMA (2)
Articles 1 - 30 of 36
Full-Text Articles in Cell Biology
Dibutyltin Alters Immune Cell Production Of The Pro-Inflammatory Cytokines Interleukin (Il) 1Β And Il-6: Role Of Mitogen-Activated Protein Kinases And Changes In Mrna, Linda B Sushak, Sahra Gabure, Jaquel Maise, Jessica Arnett, Margaret Whalen
Dibutyltin Alters Immune Cell Production Of The Pro-Inflammatory Cytokines Interleukin (Il) 1Β And Il-6: Role Of Mitogen-Activated Protein Kinases And Changes In Mrna, Linda B Sushak, Sahra Gabure, Jaquel Maise, Jessica Arnett, Margaret Whalen
Chemistry Faculty Research
Dibutyltin (DBT) is used to stabilize plastics and as a deworming agent in some poultry. It is found in human blood (levels as high as 0.3 μM). Interleukin (IL) 1β (IL-1β) and IL-6 are pro-inflammatory cytokines produced by lymphocytes, monocytes, and other cells. Elevated levels of IL-1β and IL-6 have been associated with pathologies including rheumatoid arthritis and cancers. DBT was shown to decrease IL-1β and IL-6 secretion from immune cells at higher concentrations while causing increases at lower concentrations. However, it was not clear if these changes were due to DBT's alteration of the secretory process or due its …
Exposures To The Environmental Contaminants Pentachlorophenol (Pcp) And Dichlorodiphenyltrichloroethane (Ddt) Increase Production Of The Pro-Inflammatory Cytokine, Interleukin 1-Βeta (Il-1Β), In Human Immune Cells, Tamara J. Martin, Jaquel Maise, Sahra Gabure, Margaret M. Whalen
Exposures To The Environmental Contaminants Pentachlorophenol (Pcp) And Dichlorodiphenyltrichloroethane (Ddt) Increase Production Of The Pro-Inflammatory Cytokine, Interleukin 1-Βeta (Il-1Β), In Human Immune Cells, Tamara J. Martin, Jaquel Maise, Sahra Gabure, Margaret M. Whalen
Chemistry Faculty Research
Pentachlorophenol (PCP) and dichlorodiphenyltrichloroethane (DDT), are organochlorine environmental contaminants found in human blood at very significant levels (as high as 5 µM for PCP and 260 nM for DDT). Cancers of the blood (lymphoma and myeloma) and kidney as well as others have been associated with exposure to these contaminants. Interleukin 1 beta (IL-1β) is a pro-inflammatory cytokine and is involved in stimulating cell proliferation. High levels of IL-1β are associated with inflammatory diseases and tumor progression. Previous studies showed that PCP and DDT at certain concentrations were able to stimulate secretion of IL-1β. This study shows that the increased …
Synthesis Of Interleukin 1 Beta And Interleukin 6 In Human Lymphocytes Is Stimulated By Tributyltin, Shyretha Brown, Mariam Boules, Nafisa Hamza, Xiaofei Wang, Margaret Whalen
Synthesis Of Interleukin 1 Beta And Interleukin 6 In Human Lymphocytes Is Stimulated By Tributyltin, Shyretha Brown, Mariam Boules, Nafisa Hamza, Xiaofei Wang, Margaret Whalen
Chemistry Faculty Research
Tributyltin (TBT) is a widespread environmental contaminant that is present in human blood and other tissues. It has been shown to disrupt the immune function of human natural killer (NK) cells and to alter the secretion of a number of pro-inflammatory cytokines from immune cells. Secretion of both interleukin 1β (IL-1β) and interleukin 6 (IL-6) from human lymphocytes can be increased dependent upon the level of TBT exposure. This study shows that the TBT-induced increases in secretion of both cytokines are due to TBT-induced increases in the synthesis of these proteins and not simply because of the release of pre-existing …
Tributyltin Stimulates Synthesis Of Interferon Gamma And Tumor Necrosis Factor Alpha In Human Lymphocytes, Shanieek Lawrence, Farah Ismail, Sarah Z. Jamal, Margaret M. Whalen
Tributyltin Stimulates Synthesis Of Interferon Gamma And Tumor Necrosis Factor Alpha In Human Lymphocytes, Shanieek Lawrence, Farah Ismail, Sarah Z. Jamal, Margaret M. Whalen
Chemistry Faculty Research
Tributyltin (TBT) is found in human blood and other tissues and thus is of considerable concern as to its effects on human health. Previous studies have demonstrated that TBT has detrimental effects on immune function. Recently, we found that exposures to TBT caused increased secretion of two important proinflammatory cytokines, tumor necrosis factor alpha (TNFα) and interferon gamma (IFNγ). Elevation of either of these cytokines has the potential to cause chronic inflammation, which is an important factor in a number of diseases including cancer. The current study examined the mechanism of TBT-induced elevations of TNFα and IFNγ secretion and found …
Flame Retardants, Hexabromocyclododecane (Hcbd) And Tetrabromobisphenol A (Tbbpa), Alter Secretion Of Tumor Necrosis Factor Alpha (Tnfα) From Human Immune Cells, Sharia Yasmin, Margaret Whalen
Flame Retardants, Hexabromocyclododecane (Hcbd) And Tetrabromobisphenol A (Tbbpa), Alter Secretion Of Tumor Necrosis Factor Alpha (Tnfα) From Human Immune Cells, Sharia Yasmin, Margaret Whalen
Chemistry Faculty Research
Hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) are flame retardants, used in a variety of applications, which contaminate the environment and are found in human blood. HBCD and TBBPA have been shown to alter the tumor killing function of natural killer (NK) lymphocytes and the secretion of the inflammatory cytokines interferon gamma (IFNγ) and interleukin 1 beta (IL-1β). The current study examined the effects of HBCD and TBBPA on secretion of the critical pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) from human immune cells. Preparations of human immune cells that ranged in complexity were studied to determine if the effects of …
Butyltin Compounds Alter Secretion Of Interleukin 6 From Human Immune Cells, Shyretha Brown, Wendy Wilburn, Tyesha Martin, Margaret Whalen
Butyltin Compounds Alter Secretion Of Interleukin 6 From Human Immune Cells, Shyretha Brown, Wendy Wilburn, Tyesha Martin, Margaret Whalen
Chemistry Faculty Research
Butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT) are organotin compounds that have been used in a variety of industrial applications; as a result, these compounds have been found in human blood. Interleukin (IL)-6 is a proinflammatory mediator that is produced by T lymphocytes and monocytes. It is responsible for immune response regulation as well as tissue repair and cellular growth. Both BTs decrease the ability of human natural killer cells to destroy tumor cells and alter the secretion of proinflammatory cytokines tumor necrosis factor alpha, interferon gamma and IL-1 beta (β) from human lymphocytes ex vivo. Here, we show that …
Effects Of Pentachlorophenol And Dichlorodiphenyltrichloroethane On Secretion Of Interferon Gamma (Ifnγ) And Tumor Necrosis Factor Alpha (Tnfα) From Human Immune Cells, Reda Massawe, Leon Drabo, Margaret Whalen
Effects Of Pentachlorophenol And Dichlorodiphenyltrichloroethane On Secretion Of Interferon Gamma (Ifnγ) And Tumor Necrosis Factor Alpha (Tnfα) From Human Immune Cells, Reda Massawe, Leon Drabo, Margaret Whalen
Chemistry Faculty Research
Pentachlorophenol (PCP) and dichlorodiphenyltrichloroethane (DDT) are pesticides that have been widely used and significantly contaminate the environment. Both are found in human blood and have been shown to alter the lytic and binding function of human natural killer (NK) cells. Interferon gamma (IFNγ) and tumor necrosis factor alpha (TNFα) are pro-inflammatory cytokines, which regulate immune responsiveness to pathogens and tumors. Their levels require very tight control to prevent loss of immune competence or excessive inflammation. Here, we examined the capacity of PCP and DDT to alter the secretion of these critical pro-inflammatory cytokines from increasingly reconstituted (more complex) preparations of …
Exposures To The Environmental Toxicants Pentachlorophenol (Pcp) And Dichlorodiphenyltrichloroethane (Ddt) Modify Secretion Of Interleukin 1-Beta (Il-1Β) From Human Immune Cells, Tamara J. Martin, Margaret M. Whalen
Exposures To The Environmental Toxicants Pentachlorophenol (Pcp) And Dichlorodiphenyltrichloroethane (Ddt) Modify Secretion Of Interleukin 1-Beta (Il-1Β) From Human Immune Cells, Tamara J. Martin, Margaret M. Whalen
Chemistry Faculty Research
Pentachlorophenol (PCP) and Dichlorodiphenyltrichloroethane (DDT) are environmental contaminants found in human blood. Previous studies have shown that PCP and DDT inhibit the lytic function of highly purified human natural killer (NK) lymphocytes and decrease the expression of several surface proteins on NK cells. Interleukin-1 βeta (IL-1β) is a cytokine produced by lymphocytes and monocytes, and anything that elevates its levels inappropriately can lead to chronic inflammation, which among other consequences can increase tumor development and invasiveness. Here, PCP and DDT were examined for their ability to alter secretion of IL-1β from immune cell preparations of various complexity: NK cells; monocyte-depleted …
Dibutyltin-Induced Alterations Of Interleukin 1beta Secretion From Human Immune Cells, Shyretha Brown, Shahin Tehrani, Margaret M. Whalen
Dibutyltin-Induced Alterations Of Interleukin 1beta Secretion From Human Immune Cells, Shyretha Brown, Shahin Tehrani, Margaret M. Whalen
Chemistry Faculty Research
Dibutyltin (DBT) is used to stabilize polyvinyl chloride plastics (including pipes that distribute drinking water) and as a de-worming agent in poultry. DBT is found in human blood, and DBT exposures alter the secretion of tumor necrosis factor alpha and interferon gamma from lymphocytes. Interleukin (IL)-1β is a proinflammatory cytokine that regulates cellular growth, tissue restoration and immune response regulation. IL-1β plays a role in increasing invasiveness of certain tumors. This study reveals that exposures to DBT (24 h, 48 h and 6 days) modify the secretion of IL-1β from increasingly reconstituted preparations of human immune cells (highly enriched human …
Effect Of Quercetin, Genistein And Kaempferol On Glutathione And Glutathione-Redox Cycle Enzymes In 3t3-L1 Preadipocytes, William Y. Boadi, Paul K. Amartey, Andrew Lo
Effect Of Quercetin, Genistein And Kaempferol On Glutathione And Glutathione-Redox Cycle Enzymes In 3t3-L1 Preadipocytes, William Y. Boadi, Paul K. Amartey, Andrew Lo
Chemistry Faculty Research
Context and objective: Many studies have shown that cellular redox potential is largely determined by glutathione (GSH), which accounts for more than 90% of cellular nonprotein thiols. The aim of this study was to delineate the effect of three flavonoids – namely, quercetin, kaempferol and genistein – and exogenous GSH on oxidative damage by the Fenton’s pathway through the GSH and GSH-redox cycle enzymes in 3T3-L1 cells. Materials and methods: 3T3-L1 preadipocytes were exposed to each flavonoid and GSH at concentrations of 0, 5, 10, 15, 20 and 25 µM and then GSH levels and activities of glutathione peroxidase (GSH-Px), …
Hexabromocyclododecane And Tetrabromobisphenol A Alter Secretion Of Interferon Gamma (Ifn-Γ) From Human Immune Cells, Haifa Almughamsi, Margaret M. Whalen
Hexabromocyclododecane And Tetrabromobisphenol A Alter Secretion Of Interferon Gamma (Ifn-Γ) From Human Immune Cells, Haifa Almughamsi, Margaret M. Whalen
Chemistry Faculty Research
Hexabromocyclododecane (HBCD) and tetrabromobisphenol A (TBBPA) are brominated flame-retardant compounds used in a variety of applications including insulation, upholstery, and epoxy resin circuit boards. Interferon gamma (IFN-γ) is an inflammatory cytokine produced by activated T and NK cells that regulates immune responsiveness. HBCD and TBBPA are found in human blood, and previous studies have shown that they alter the ability of human natural killer (NK) lymphocytes to destroy tumor cells. This study examines whether HBCD and TBBPA affect the secretion of IFN-γ from increasingly complex preparations of human immune cells—purified NK cells, monocyte-depleted (MD) peripheral blood mononuclear cells (PBMCs), and …
Activation Of Protein Kinase C And Protein Kinase D In Human Natural Killer Cells: Effects Of Tributyltin, Dibutyltin, And Tetrabromobisphenol A, Krupa Rana, Margaret Whalen
Activation Of Protein Kinase C And Protein Kinase D In Human Natural Killer Cells: Effects Of Tributyltin, Dibutyltin, And Tetrabromobisphenol A, Krupa Rana, Margaret Whalen
Chemistry Faculty Research
Up to now, the ability of target cells to activate protein kinase C (PKC) and protein kinase D (PKD) (which is often a downstream target of PKC) has not been examined in natural killer (NK) lymphocytes. Here we examined whether exposure of human NK cells to lysis sensitive tumor cells activated PKC and PKD. The results of these studies show for the first time that activation of PKC and PKD occurs in response to target cell binding to NK cells. Exposure of NK cells to K562 tumor cells for 10 and 30 min increased phosphorylation/activation of both PKC and PKD …
Tributyltin Alters Secretion Of Interleukin 1 Beta From Human Immune Cells, Shyretha Brown, Margaret Whalen
Tributyltin Alters Secretion Of Interleukin 1 Beta From Human Immune Cells, Shyretha Brown, Margaret Whalen
Chemistry Faculty Research
Tributyltin (TBT) has been used as a biocide in industrial applications such as wood preservation, antifouling paint and antifungal agents. Owing to its many uses, it contaminates the environment and has been found in human blood samples. Interleukin-1 beta (IL-1β) is a pro-inflammatory cytokine that promotes cell growth, tissue repair and immune response regulation. Produced predominately by both monocytes and macrophages, IL-1β appears to increase the invasiveness of certain tumors. This study shows that TBT modifies the secretion of IL-1β from increasingly reconstituted preparations of human immune cells. IL-1β secretion was examined after 24-, 48-h or 6-day exposures to TBT …
Brominated Flame Retardants, Tetrabromobisphenol A And Hexabromocyclododecane, Activate Mitogen-Activated Protein Kinases (Mapks) In Human Natural Killer Cells, Anita Cato, Lindsay Celada, Esther Caroline Kibakaya, Nadia Simmons, Margaret M. Whalen
Brominated Flame Retardants, Tetrabromobisphenol A And Hexabromocyclododecane, Activate Mitogen-Activated Protein Kinases (Mapks) In Human Natural Killer Cells, Anita Cato, Lindsay Celada, Esther Caroline Kibakaya, Nadia Simmons, Margaret M. Whalen
Chemistry Faculty Research
Natural killer (NK) cells provide a vital surveillance against virally infected cells, tumor cells, and antibody-coated cells through the release of cytolytic mediators and gamma interferon (IFN-γ). Hexabromocyclododecane (HBCD) is a brominated flame retardant used primarily in expanded (EPS) and extruded (XPS) polystyrene foams for thermal insulation in the building and construction industry. Tetrabromobisphenol A (TBBPA) is used both as a reactive and an additive flame retardant in a variety of materials. HBCD and TBBPA contaminate the environment and are found in human blood samples. In previous studies, we have shown that other environmental contaminants, such as the dibutyltin (DBT) …
Secretion Of Interferon Gamma From Human Immune Cells Is Altered By Exposure To Tributyltin And Dibutyltin, Shanieek Lawrence, Jacqueline Reid, Margaret Whalen
Secretion Of Interferon Gamma From Human Immune Cells Is Altered By Exposure To Tributyltin And Dibutyltin, Shanieek Lawrence, Jacqueline Reid, Margaret Whalen
Chemistry Faculty Research
Tributyltin (TBT) and dibutyltin (DBT) are widespread environmental contaminants found in food, beverages, and human blood samples. Both of these butyltins (BTs) interfere with the ability of human natural killer (NK) cells to lyse target cells and alter secretion of the pro-inflammatory cytokine tumor necrosis factor alpha (TNFα) from human immune cells in vitro. The capacity of BTs to interfere with secretion of other pro-inflammatory cytokines has not been examined. Interferon gamma (IFNγ) is a modulator of adaptive and innate immune responses, playing an important role in overall immune competence. This study shows that both TBT and DBT alter secretion …
Effects Of Butyltins On Mitogen-Activated-Protein Kinase Kinase Kinase And Ras Activity In Human Natural Killer Cells, Lindsay J. Celada, Margaret M. Whalen
Effects Of Butyltins On Mitogen-Activated-Protein Kinase Kinase Kinase And Ras Activity In Human Natural Killer Cells, Lindsay J. Celada, Margaret M. Whalen
Chemistry Faculty Research
Butyltins (BTs) contaminate the environment and are found in human blood. BTs, tributyltin (TBT) and dibutyltin (DBT) diminish the cytotoxic function and levels of key proteins of human natural killer (NK) cells. NK cells are an initial immune defense against tumors, virally infected cells and antibody-coated cells and thus critical to human health. The signaling pathways that regulate NK cell functions include mitogen-activated protein kinases (MAPKs). Studies have shown that exposure to BTs leads to activation of specific MAPKs and MAPK kinases (MAP2Ks) in human NK cells. MAP2K kinases (MAP3Ks) are upstream activators of MAP2Ks, which then activate MAPKs. The …
Tributyltin And Dibutyltin Alter Secretion Of Tumor Necrosis Factor Alpha From Human Natural Killer Cells And A Mixture Of T Cells And Natural Killer Cells, Kelsi Hurt, Tasia Hurd-Brown, Margaret Whalen
Tributyltin And Dibutyltin Alter Secretion Of Tumor Necrosis Factor Alpha From Human Natural Killer Cells And A Mixture Of T Cells And Natural Killer Cells, Kelsi Hurt, Tasia Hurd-Brown, Margaret Whalen
Chemistry Faculty Research
Butyltins (BTs) have been in widespread use. Tributyltin (TBT) has been used as a biocide in a variety of applications and is found in human blood samples. Dibutyltin (DBT) has been used as a stabilizer in polyvinyl chloride plastics and as a de-worming agent in poultry. DBT, like TBT, is found in human blood. Human natural killer (NK) cells are the earliest defense against tumors and viral infections and secrete the cytokine tumor necrosis factor-alpha (TNF-α). TNF-α is an important regulator of adaptive and innate immune responses. TNF-α promotes inflammation and an association between malignant transformation and inflammation has been …
Effects Of Ddt And Triclosan On Tumor-Cell Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd-Brown, Felicia Udoji, Tamara Martin, Margaret M. Whalen
Effects Of Ddt And Triclosan On Tumor-Cell Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd-Brown, Felicia Udoji, Tamara Martin, Margaret M. Whalen
Chemistry Faculty Research
1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT) and triclosan (TCS) are organochlorine (OC) compounds that contaminate the environment, are found in human blood and have been shown to decrease the tumor-cell killing (lytic) function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. They bind to these targets, utilizing a variety of cell surface proteins. The present study examined concentrations of DDT and TCS that decrease lytic function for alteration of NK binding to tumor targets. Levels of either compound that caused loss of binding function were then examined for effects on expression of cell-surface proteins needed for …
Pentachlorophenol Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd, Jasmine Walker, Margaret M. Whalen
Pentachlorophenol Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Tasia Hurd, Jasmine Walker, Margaret M. Whalen
Chemistry Faculty Research
Pentachlorophenol (PCP) is an organochlorine pesticide that decreases the tumor-cell killing (lytic) function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. They bind to these targets, utilizing a variety of cell-surface proteins. This study examined concentrations of PCP that decrease lytic function for alteration of NK binding to tumor targets. Levels of PCP that caused loss of binding function were then examined for effects on expression of cell-surface proteins needed for binding. Exposure to 10 µm PCP for 24 h (which caused a greater than 70% loss of lytic function) decreased NK …
Ziram Activates Mitogen-Activated Protein Kinases And Decreases Cytolytic Protein Levels In Human Natural Killer Cells, Thyneice R. Taylor, Margaret M. Whalen
Ziram Activates Mitogen-Activated Protein Kinases And Decreases Cytolytic Protein Levels In Human Natural Killer Cells, Thyneice R. Taylor, Margaret M. Whalen
Chemistry Faculty Research
Human natural killer (NK) cells are central in immune defense with their ability to lyse tumor cells and virally infected cells. Tumor formation and viral infection may increase if NK cytotoxic function is disrupted. Ziram (zinc dithiocarbamate) is used as an accelerating agent in the production of latex and to protect various fruits and vegetables from fungal infection. Previously, we have shown that exposure to ziram inhibits NK lytic function. Butyltin environmental contaminants, which also inhibit NK lytic function, cause rapid activations of mitogen-activated protein kinases (MAPKs) and decreases in expression of the cytolytic proteins granzyme B and perforin (after …
Tetrabromobisphenol A Decreases Cell-Surface Proteins Involved In Human Natural Killer (Nk) Cell–Dependent Target Cell Lysis, Tasia Hurd, Margaret M. Whalen
Tetrabromobisphenol A Decreases Cell-Surface Proteins Involved In Human Natural Killer (Nk) Cell–Dependent Target Cell Lysis, Tasia Hurd, Margaret M. Whalen
Chemistry Faculty Research
Human natural killer (NK) lymphocytes are able to destroy tumor cells and virally-infected cells. Interference with their function can leave an individual with increased susceptibility to cancer development and/or viral infection. We have shown that the tumor-destroying (lytic) function of NK cells can be dramatically decreased by exposure to the environmental contaminant tetrabromobisphenol A (TBBPA). TBBPA is a flame retardant used in a variety of materials including circuit boards, carpeting, and upholstery and has been found in human blood samples. TBBPA interferes with NK cell lytic function, in part, by decreasing the ability of NK cells to bind to target …
Activation Of P44/42 In Human Natural Killer Cells Decreases Cell-Surface Protein Expression: Relationship To Tributyltin-Induced Alterations Of Protein Expression, Fred D. Dudimah, Abraham Abraha, Xiaofei Wang, Margaret M. Whalen
Activation Of P44/42 In Human Natural Killer Cells Decreases Cell-Surface Protein Expression: Relationship To Tributyltin-Induced Alterations Of Protein Expression, Fred D. Dudimah, Abraham Abraha, Xiaofei Wang, Margaret M. Whalen
Chemistry Faculty Research
Tributyltin (TBT) activates the mitogen activated protein kinase (MAPK), p44/42 in human natural killer (NK) cells. TBT also reduces NK cytotoxic function and decreases the expression of several NK-cell proteins. To understand the role that p44/42 activation plays in TBT-induced loss of NK cell function, this study investigated how selective activation of p44/42 by phorbol 12-myristate 13-acetate (PMA) affects NK cells. Previously it was shown that PMA caused losses of lytic function similar to those seen with TBT exposures. This study examined activation of p44/42 in the regulation of NK-cell protein expression and how this regulation may explain the protein …
Role Of Protein Kinase C In Tbt-Induced Inhibition Of Lytic Function And Mapk Activation In Human Natural Killer Cells, Abraham B. Abraha, Krupa Rana, Margaret M. Whalen
Role Of Protein Kinase C In Tbt-Induced Inhibition Of Lytic Function And Mapk Activation In Human Natural Killer Cells, Abraham B. Abraha, Krupa Rana, Margaret M. Whalen
Chemistry Faculty Research
Human natural killer (NK) cells are lymphocytes that destroy tumor and virally infected cells. Previous studies have shown that exposure of NK cells to tributyltin (TBT) greatly diminishes their ability to destroy tumor cells (lytic function) while activating mitogen-activated protein kinases (MAPK) (p44/42, p38, and JNK) in NK cells. The signaling pathway that regulates NK lytic function appears to include activation of protein kinase C (PKC) as well as MAPK activity. TBT-induced activation of MAPKs would trigger a portion of the NK lytic signaling pathway, which would then leave the NK cell unable to trigger this pathway in response to …
Effects Of Butyltin Exposures On Map Kinase-Dependent Transcription Regulators In Human Natural Killer Cells, Rachel J. Person, Margaret M. Whalen
Effects Of Butyltin Exposures On Map Kinase-Dependent Transcription Regulators In Human Natural Killer Cells, Rachel J. Person, Margaret M. Whalen
Chemistry Faculty Research
Natural killer (NK) cells are a major immune defense mechanism against cancer development and viral infection. The butyltins (BTs), tributyltin (TBT) and dibutyltin (DBT), have been widely used in industrial and other applications and significantly contaminate the environment. Both TBT and DBT have been detected in human blood. These compounds inhibit the lytic and binding function of human NK cells and thus could increase the incidence of cancer and viral infections. Butyltin (BT)-induced loss of NK function is accompanied by activation of mitogen activated protein kinases (MAPKs) and decreases in expression of cell-surface and cytolytic proteins. MAPKs activate components of …
Dibutyltin Activates Map Kinases In Human Natural Killer Cells, In Vitro, Sabah O. Odman-Ghazi, Abraham Abraha, Erica Taylor Isom, Margaret M. Whalen
Dibutyltin Activates Map Kinases In Human Natural Killer Cells, In Vitro, Sabah O. Odman-Ghazi, Abraham Abraha, Erica Taylor Isom, Margaret M. Whalen
Chemistry Faculty Research
Previous studies have shown that dibutyltin (DBT) interferes with the function of human natural killer (NK) cells, diminishing their capacity to destroy tumor cells, in vitro. DBT is a widespread environmental contaminant and has been found in human blood. As NK cells are our primary immune defense against tumor cells, it is important to understand the mechanism by which DBT interferes with their function. The current study examines the effects of DBT exposures on key enzymes in the signaling pathway that regulates NK responsiveness to tumor cells. These include several protein tyrosine kinases (PTKs), mitogen-activated protein kinases (MAPKs), and mitogen-activated …
Immunosuppressive Effects Of Triclosan, Nonylphenol, And Ddt On Human Natural Killer Cells In Vitro, Felicia Udoji, Tamara Martin, Rachel Etherton, Margaret M. Whalen
Immunosuppressive Effects Of Triclosan, Nonylphenol, And Ddt On Human Natural Killer Cells In Vitro, Felicia Udoji, Tamara Martin, Rachel Etherton, Margaret M. Whalen
Chemistry Faculty Research
Human natural killer (NK) cells are a first-line immune defense against tumor cells and virally-infected cells. If their function is impaired, it leaves an individual more susceptible to cancer development or viral infection. The ability of compounds that contaminate the environment to suppress the function of NK cells could contribute to the increased risk of cancer development. There are a wide spectrum of compounds that significantly contaminate water and food that are consumed by humans, leading to accumulation of some of these compounds in human tissues. In the current study, we examined the ability of three such compounds to diminish …
Activation Of P44/42 Mapk Plays A Role In The Tbt-Induced Loss Of Human Natural Killer (Nk) Cell Function, Fred D. Dudimah, Denisha Griffey, Xiaofei Wang, Margaret M. Whalen
Activation Of P44/42 Mapk Plays A Role In The Tbt-Induced Loss Of Human Natural Killer (Nk) Cell Function, Fred D. Dudimah, Denisha Griffey, Xiaofei Wang, Margaret M. Whalen
Chemistry Faculty Research
Natural killer (NK) cells destroy (lyse) tumor cells, virally infected cells, and antibody-coated cells. Previous studies indicated that exposure to the environmental contaminant tributyltin (TBT) decreases the lytic function of NK cells and activates mitogen-activated protein kinases (MAPK), including p44/42 (Aluoch and Whalen Toxicology 209:263–277, 2005). If activation of p44/42 is required for TBT-induced decreases of lytic function, then activation of p44/42 to similar extents by pharmacological agents such as phorbol 12-myristate 13-acetate (PMA) should mimic to some extent changes induced in NK cells with TBT exposures. NK cells were exposed to PMA concentrations between 0.25 and 10 nM for …
Hexabromocyclododecane Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Natasha C. Hinkson, Margaret M. Whalen
Hexabromocyclododecane Decreases Tumor-Cell-Binding Capacity And Cell-Surface Protein Expression Of Human Natural Killer Cells, Natasha C. Hinkson, Margaret M. Whalen
Chemistry Faculty Research
Hexabromocyclododecane (HBCD) is a flame retardant that decreases the lytic function of human natural killer (NK) cells. NK cells defend against tumor cells and virally infected cells. Thus, HBCD has the potential to increase cancer incidence and viral infections. NK cells must bind to their targets for lysis to occur. Thus, concentrations of HBCD that decrease lytic function were examined for their ability to alter NK binding to tumor targets. Levels of HBCD that caused a loss of binding function were examined for effects on expression of cell surface proteins needed for binding. NK cells exposed to HBCD for 24 …
Tetrabromobisphenol A Has Immunosuppressive Effects On Human Natural Killer Cells, Esther Caroline Kibakaya, Krishna Stephen, Margaret M. Whalen
Tetrabromobisphenol A Has Immunosuppressive Effects On Human Natural Killer Cells, Esther Caroline Kibakaya, Krishna Stephen, Margaret M. Whalen
Chemistry Faculty Research
Human natural killer (NK) cells are lymphocytes that destroy tumor cells, virally-infected cells, and antibody-coated cells. Tetrabromobisphenol A (TBBPA) is used both as a reactive and as an additive flame retardant in a variety of materials and appears to contaminate the environment. TBBPA has been found in human blood samples and if it interferes with NK cell function, this could increase the risk of tumor development and/or viral infection. The present study examines the effects of exposure to various concentrations of TBBPA for 24 hr, 48 hr, and 6 days on the lytic function, tumor-target-binding function, and ATP levels of …
Hexabromocyclododecane Decreases The Lytic Function And Atp Levels Of Human Natural Killer Cells, Natasha C. Hinkson, Margaret M. Whalen
Hexabromocyclododecane Decreases The Lytic Function And Atp Levels Of Human Natural Killer Cells, Natasha C. Hinkson, Margaret M. Whalen
Chemistry Faculty Research
This study investigates the effect of hexabromocyclododecane (HBCD) on the lytic function of human natural killer (NK) cells and on ATP levels in NK cells. NK cells are capable of lysing tumor cells, virally infected cells, and antibody-coated cells. HBCD is a brominated cyclic alkane used primarily as an additive flame retardant. If HBCD interferes with NK cell function, this could increase risk of tumor development and/or viral infection. NK cells were exposed to various concentrations of HBCD for 24 and 48 h and 6 days before determining lytic function and ATP levels. ATP levels and lytic function were also …