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Eskandari E, Eaves CJ. Paradoxical roles of caspase-3 in regulating cell survival, proliferation, and tumorigenesis. J Cell Biol 2022; 221:213213. [PMID: 35551578 PMCID: PMC9106709 DOI: 10.1083/jcb.202201159] [Citation(s) in RCA: 89] [Impact Index Per Article: 44.5] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 04/11/2022] [Accepted: 04/18/2022] [Indexed: 11/22/2022] Open
Abstract
Caspase-3 is a widely expressed member of a conserved family of proteins, generally recognized for their activated proteolytic roles in the execution of apoptosis in cells responding to specific extrinsic or intrinsic inducers of this mode of cell death. However, accumulating evidence indicates that caspase-3 also plays key roles in regulating the growth and homeostatic maintenance of both normal and malignant cells and tissues in multicellular organisms. Given that yeast possess an ancestral caspase-like gene suggests that the caspase-3 protein may have acquired different functions later during evolution to better meet the needs of more complex multicellular organisms, but without necessarily losing all of the functions of its ancestral yeast precursor. This review provides an update on what has been learned about these interesting dichotomous roles of caspase-3, their evolution, and their potential relevance to malignant as well as normal cell biology.
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Affiliation(s)
- Ebrahim Eskandari
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Connie J. Eaves
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia, Canada,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada,School of Biomedical Engineering, University of British Columbia, Vancouver, British Columbia, Canada,Correspondence to Connie J. Eaves:
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2
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Solier S, Fontenay M, Vainchenker W, Droin N, Solary E. Non-apoptotic functions of caspases in myeloid cell differentiation. Cell Death Differ 2017; 24:1337-1347. [PMID: 28211870 DOI: 10.1038/cdd.2017.19] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 01/06/2017] [Accepted: 01/16/2017] [Indexed: 12/26/2022] Open
Abstract
Subtle caspase activation is associated with the differentiation of several myeloid lineages. A tightly orchestrated dance between caspase-3 activation and the chaperone HSP70 that migrates to the nucleus to protect the master regulator GATA-1 from cleavage transiently occurs in basophilic erythroblasts and may prepare nucleus and organelle expel that occurs at the terminal phase of erythroid differentiation. A spatially restricted activation of caspase-3 occurs in maturing megakaryocytes to promote proplatelet maturation and platelet shedding in the bloodstream. In a situation of acute platelet need, caspase-3 could be activated in response to IL-1α and promote megakaryocyte rupture. In peripheral blood monocytes, colony-stimulating factor-1 provokes the formation of a molecular platform in which caspase-8 is activated, which downregulates nuclear factor-kappa B (NF-κB) activity and activates downstream caspases whose target fragments such as those generated by nucleophosmin (NPM1) cleavage contribute to the generation of resting macrophages. Human monocytes secrete mature IL-1β in response to lipopolysaccharide through an alternative inflammasome activation that involves caspase-8, a pathway that does not lead to cell death. Finally, active caspase-3 is part of the proteases contained in secretory granules of mast cells. Many questions remain on how these proteases are activated in myeloid cell lineages, which target proteins are cleaved, whereas other are protected from proteolysis, the precise role of cleaved proteins in cell differentiation and functions, and the link between these non-apoptotic functions of caspases and the death of these diverse cell types. Better understanding of these functions may generate therapeutic strategies to control cytopenias or modulate myeloid cell functions in various pathological situations.
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Affiliation(s)
- Stéphanie Solier
- Inserm U1170, Université Paris-Sud, Faculté de Médecine Paris-Sud, Gustave Roussy, Villejuif, France
| | - Michaela Fontenay
- INSERM U1016, Institut Cochin, Paris, France.,Assistance Publique-Hôpitaux de Paris, Service d'Hématologie Biologique, Hôpitaux Universitaires Paris Centre, Paris, France
| | - William Vainchenker
- Inserm U1170, Université Paris-Sud, Faculté de Médecine Paris-Sud, Gustave Roussy, Villejuif, France
| | - Nathalie Droin
- Inserm U1170, Université Paris-Sud, Faculté de Médecine Paris-Sud, Gustave Roussy, Villejuif, France
| | - Eric Solary
- Inserm U1170, Université Paris-Sud, Faculté de Médecine Paris-Sud, Gustave Roussy, Villejuif, France.,Department of Hematology, Gustave Roussy, Villejuif, France
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3
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Zhou W, Yuan J. Necroptosis in health and diseases. Semin Cell Dev Biol 2014; 35:14-23. [PMID: 25087983 DOI: 10.1016/j.semcdb.2014.07.013] [Citation(s) in RCA: 295] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2014] [Accepted: 07/22/2014] [Indexed: 12/19/2022]
Abstract
Necroptosis is a form of regulated necrosis that can be activated by ligands of death receptors and stimuli that induce the expression of death receptor ligands under apoptotic deficient conditions. Activation of necroptosis by ligands of death receptors requires the kinase activity of RIP1, which mediates the activation of RIP3 and MLKL, two critical downstream mediators of necroptosis. Blocking the kinase activity of RIP1, a key druggable target in the necroptosis pathway, by necrostatins inhibits the activation of necroptosis and allows cell survival and proliferation in the presence of death receptor ligands. The activation of necroptosis is modulated by different forms of ubiquitination, including K63, linear and K48 ubiquitination, as well as phosphorylation of RIP1, RIP3 and MLKL. Necroptosis is suppressed by caspase-8/FADD-mediated apoptosis. Deficiency in caspase-8 and FADD leads to embryonic lethality, tissue degeneration and inflammation which can be suppressed by inhibition of RIP1 kinase and RIP3. On the other hand, the lack of RIP3 kinase activity leads to early embryonic lethality which can be suppressed by the loss of caspase-8, suggesting that although the kinase activity of RIP3 is involved in mediating necroptosis, the basal activity of RIP3 kinase may be required for suppressing caspase-8 mediated apoptosis. Necroptosis as well as RIP1- and RIP3-mediated inflammatory response have been implicated in mediating multiple human diseases including TNF-mediated hypothermia and systemic inflammation, ischemic reperfusion injury, neurodegeneration, Gaucher's disease, progressive atherosclerotic lesions, etc. Targeting RIP1 kinase may provide therapeutic benefits for the treatment of human diseases characterized by necrosis and inflammation.
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Affiliation(s)
- Wen Zhou
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA
| | - Junying Yuan
- Department of Cell Biology, Harvard Medical School, 240 Longwood Avenue, Boston, MA 02115, USA.
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4
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IL-15 maintains T-cell survival via S-nitrosylation-mediated inhibition of caspase-3. Cell Death Differ 2014; 21:904-14. [PMID: 24510126 DOI: 10.1038/cdd.2014.10] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2013] [Revised: 12/27/2013] [Accepted: 01/08/2014] [Indexed: 12/18/2022] Open
Abstract
Caspase activity is critical for both T-cell survival and death. However, little is known regarding what determines caspase activity in cycling T cells. Interleukin (IL)-2 and IL-15 confer very different susceptibilities to T-cell death. We therefore considered that IL-2 and IL-15 differentially regulate caspase activity to influence T-cell survival. We observed that IL-2-cultured primary murine effector T cells manifested elevated levels of caspase-3 activity compared with IL-15-cultured T cells. T cell receptor (TCR) restimulation further increased caspase activity and induced considerable cell death in IL-2-cultured T cells, but provoked only a minimal increase of caspase activity and cell death in IL-15-cultured T cells. IL-2 sensitization to cell death was caspase-3 mediated. Interestingly, increased active caspase-3 levels with IL-2 were independent of active initiator caspase-8 and caspase-9 that were similar with IL-2 and IL-15. Rather, caspase-3 activity was inhibited by posttranslational S-nitrosylation in IL-15-cultured T cells, but not in the presence of IL-2. This paralleled increased reactive nitrogen and oxygen species with IL-15 and reduced glycolysis. Taken together, these data suggest that the metabolic state conferred by IL-15 inhibits T-cell apoptosis in part by maintaining low levels of active caspase-3 via S-nitrosylation.
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5
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Koenig A, Fortner KA, King BR, Madden J, Buskiewicz IA, Budd RC. Proliferating γδ T cells manifest high and spatially confined caspase-3 activity. Immunology 2012; 135:276-86. [PMID: 22117649 DOI: 10.1111/j.1365-2567.2011.03540.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Caspase-8 serves two paradoxical roles in T lymphocytes: it initiates apoptosis following death receptor engagement, and is also indispensible for proliferation following T-cell antigen receptor (TCR) signalling. These opposing processes appear to be controlled by both spatial and quantitative differences in caspase-8 activation. Given differences in the turnover of T-cell subsets, we compared caspase activity and susceptibility to cell death following TCR restimulation in murine CD4(+) and CD8(+) αβ T cells and γδ T cells. We observed a spectrum of caspase activity in non-dying effector T cells in which CD4(+) T cells manifested the lowest levels of active caspases whereas γδ T cells manifested the highest levels. Further analysis revealed that most of the difference in T-cell subsets was the result of high levels of active caspase-3 in non-dying effector γδ T cells. Despite this, γδ T cells manifested little spontaneous or CD3 restimulation-induced cell death as the result of confinement of active caspases to the cell membrane. By contrast, CD4(+) T cells were highly sensitive to CD3-induced cell death, associated with the appearance of active caspases in the cytoplasm and cleavage of the caspase substrates Bid and ICAD. Hence, the location and amount of active caspases distinguishes effector T-cell subsets and profoundly influences the fate of the T-cell response.
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Affiliation(s)
- Andreas Koenig
- Department of Medicine, Immunobiology Program, The University of Vermont College of Medicine, Burlington, VT 05405, USA.
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6
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Moujalled DM, Cook WD, Lluis JM, Khan NR, Ahmed AU, Callus BA, Vaux DL. In mouse embryonic fibroblasts, neither caspase-8 nor cellular FLICE-inhibitory protein (FLIP) is necessary for TNF to activate NF-κB, but caspase-8 is required for TNF to cause cell death, and induction of FLIP by NF-κB is required to prevent it. Cell Death Differ 2011; 19:808-15. [PMID: 22095280 DOI: 10.1038/cdd.2011.151] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Binding of TNF to TNF receptor-1 can give a pro-survival signal through activation of p65/RelA NF-κB, but also signals cell death. To determine the roles of FLICE-inhibitory protein (FLIP) and caspase-8 in TNF-induced activation of NF-κB and apoptosis, we used mouse embryonic fibroblasts derived from FLIP and caspase-8 gene-deleted mice, and treated them with TNF and a smac-mimetic compound that causes degradation of cellular inhibitor of apoptosis proteins (cIAPs). In cells treated with smac mimetic, TNF and Fas Ligand caused wild-type and FLIP(-/-) MEFs to die, whereas caspase-8(-/-) MEFs survived, indicating that caspase-8 is necessary for death of MEFs triggered by these ligands when IAPs are degraded. By contrast, neither caspase-8 nor FLIP was required for TNF to activate p65/RelA NF-κB, because IκB was degraded, p65 translocated to the nucleus, and an NF-κB reporter gene activated normally in caspase-8(-/-) or FLIP(-/-) MEFs. Reconstitution of FLIP(-/-) MEFs with the FLIP isoforms FLIP-L, FLIP-R, or FLIP-p43 protected these cells from dying when treated with TNF or FasL, whether or not cIAPs were depleted. These results show that in MEFs, caspase-8 is necessary for TNF- and FasL-induced death, and FLIP is needed to prevent it, but neither caspase-8 nor FLIP is required for TNF to activate NF-κB.
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Affiliation(s)
- D M Moujalled
- La Trobe Institute for Molecular Science, La Trobe University, Kingsbury Drive, Bundoora, VIC 3086, Australia
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7
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Thai PT, Collins CC, Fortner KA, Koenig A, Hayes SM, Budd RC. Increased caspase activity primes human Lyme arthritis synovial γδ T cells for proliferation and death. Hum Immunol 2011; 72:1168-75. [PMID: 21983117 DOI: 10.1016/j.humimm.2011.08.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2010] [Revised: 08/03/2011] [Accepted: 08/25/2011] [Indexed: 01/16/2023]
Abstract
γδ T cells function between the innate and adaptive immune responses, promoting antigen-presenting cell function and manifesting cytolytic activity. Their numbers often increase during infections, such as human immunodeficiency virus, and at sites of chronic inflammation. However, the turnover dynamics of human γδ T cells are poorly understood. Here we observed that despite more rapid proliferation in vitro by human Lyme arthritis synovial γδ T cells of the Vδ1 subset, they have reduced surviving cell numbers compared with αβ T cells because of increased cell death by the γδ T cells. Because caspases are involved in cell proliferation and death, and because signaling is more efficient through T cell receptor (TCR)-γδ than through TCR-αβ, we examined the levels of active caspases during cell cycling and following TCR restimulation. We observed higher overall caspase activity in Borrelia-reactive γδ T cells than in comparable αβ T cells. This was paralleled by greater spontaneous cell death and TCR restimulation-induced cell death of the γδ T cells, which was caspase dependent. Our current findings thus are consistent with a model in which human γδ T cells evolved to function quickly and transiently in an innate fashion.
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MESH Headings
- Caspases/immunology
- Caspases/metabolism
- Cell Communication/immunology
- Cell Death/immunology
- Cell Proliferation
- Cells, Cultured
- Humans
- Immunoprecipitation
- Lyme Disease/immunology
- Lyme Disease/metabolism
- Lyme Disease/pathology
- Lymphocyte Activation
- Receptors, Antigen, T-Cell, alpha-beta/immunology
- Receptors, Antigen, T-Cell, gamma-delta/immunology
- Receptors, Antigen, T-Cell, gamma-delta/metabolism
- Signal Transduction/immunology
- T-Lymphocyte Subsets/cytology
- T-Lymphocyte Subsets/immunology
- T-Lymphocyte Subsets/metabolism
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Affiliation(s)
- Phan T Thai
- Vermont Center for Immunology and Infectious Diseases, University of Vermont College of Medicine, Burlington, VT 05405, USA
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8
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Neumann L, Pforr C, Beaudouin J, Pappa A, Fricker N, Krammer PH, Lavrik IN, Eils R. Dynamics within the CD95 death-inducing signaling complex decide life and death of cells. Mol Syst Biol 2010; 6:352. [PMID: 20212524 PMCID: PMC2858442 DOI: 10.1038/msb.2010.6] [Citation(s) in RCA: 123] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2008] [Accepted: 12/23/2009] [Indexed: 12/14/2022] Open
Abstract
This study explores the dilemma in cellular signaling that triggering of CD95 (Fas/APO-1) in some situations results in cell death and in others leads to the activation of NF-kappaB. We established an integrated kinetic mathematical model for CD95-mediated apoptotic and NF-kappaB signaling. Systematic model reduction resulted in a surprisingly simple model well approximating experimentally observed dynamics. The model postulates a new link between c-FLIP(L) cleavage in the death-inducing signaling complex (DISC) and the NF-kappaB pathway. We validated experimentally that CD95 stimulation resulted in an interaction of p43-FLIP with the IKK complex followed by its activation. Furthermore, we showed that the apoptotic and NF-kappaB pathways diverge already at the DISC. Model and experimental analysis of DISC formation showed that a subtle balance of c-FLIP(L) and procaspase-8 determines life/death decisions in a nonlinear manner. We present an integrated model describing the complex dynamics of CD95-mediated apoptosis and NF-kappaB signaling.
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Affiliation(s)
- Leo Neumann
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department for Bioinformatics and Functional Genomics, Institute for Pharmacy and Molecular Biotechnology, Bioquant, University of Heidelberg, Heidelberg, Germany
| | - Carina Pforr
- Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Joel Beaudouin
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department for Bioinformatics and Functional Genomics, Institute for Pharmacy and Molecular Biotechnology, Bioquant, University of Heidelberg, Heidelberg, Germany
| | - Alexander Pappa
- Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Medac GmbH, Theaterstrasse, Wedel/Hamburg, Germany
| | - Nicolai Fricker
- Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Peter H Krammer
- Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Inna N Lavrik
- Division of Immunogenetics, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Roland Eils
- Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Department for Bioinformatics and Functional Genomics, Institute for Pharmacy and Molecular Biotechnology, Bioquant, University of Heidelberg, Heidelberg, Germany
- B080, Division of Theoretical Bioinformatics, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 580, 69120 Heidelberg, Germany. Tel.: +49 6221 5451 290; Fax: +49 6221 5451 488;
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9
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Berges C, Haberstock H, Fuchs D, Sadeghi M, Opelz G, Daniel V, Naujokat C. Proteasome inhibition activates the mitochondrial pathway of apoptosis in human CD4+T cells. J Cell Biochem 2009; 108:935-46. [DOI: 10.1002/jcb.22325] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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10
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Maret M, Ruffié C, Létuvé S, Phelep A, Thibaudeau O, Marchal J, Pretolani M, Druilhe A. A role for Bid in eosinophil apoptosis and in allergic airway reaction. THE JOURNAL OF IMMUNOLOGY 2009; 182:5740-7. [PMID: 19380821 DOI: 10.4049/jimmunol.0800864] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Bid, a proapoptotic member of Bcl-2 family, is involved in Fas receptor signaling. Fas activation promotes human eosinophil cell death and is believed to accelerate the resolution of pulmonary Th2-driven allergic reaction in mice. We hypothesized that Bid would regulate eosinophil apoptosis and Ag-induced airway inflammation, particularly eosinophilia. C57BL/6 Bid(-/-) and wild-type mice were immunized and repeatedly challenged with OVA, and bronchoalveolar lavage (BAL) fluid, lung, and spleen were collected 4-240 h after the final challenge. Cultured BAL eosinophils from Bid-deficient mice showed resistance to Fas-mediated apoptotic DNA fragmentation, phosphatidylserine exposure, mitochondria depolarization, and caspase-3 activity. In addition, OVA-challenged Bid(-/-) mice had higher BAL eosinophilia and a lower proportion of BAL apoptotic eosinophils than Bid(+/+) mice. This was accompanied by augmented BAL levels of the eosinophilotactic cytokine, IL-5, and of the eosinophil-associated mediators, TGF-beta1 and fibronectin. Finally, cultured OVA-stimulated lung mononuclear cells and splenocytes from Bid-deficient mice showed increased release of the Th2-type cytokines, IL-4 and IL-5, but no change in cell number. We conclude that Bid modulates BAL eosinophilia by regulating both eosinophil apoptosis and Th2-type cytokine production.
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Affiliation(s)
- Marielle Maret
- Institut National de la Santé et de la Recherche Médicale Unité 700 and Université Paris Diderot-Paris 7, Paris, France
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11
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Targeted cleavage of signaling proteins by caspase 3 inhibits T cell receptor signaling in anergic T cells. Immunity 2008; 29:193-204. [PMID: 18701083 DOI: 10.1016/j.immuni.2008.06.010] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2007] [Revised: 03/26/2008] [Accepted: 06/10/2008] [Indexed: 11/22/2022]
Abstract
T cell receptor (TCR) engagement in the absence of costimulation induces the calcium-dependent upregulation of a program of gene expression that leads to the establishment of T cell anergy. Casp3 is one of the genes activated during anergy induction. Here we show that caspase 3 is required for the induction of T cell unresponsiveness. Suboptimal T cell stimulation induced caspase 3 activation, which did not result in cell death. Furthermore, caspase 3-deficient T cells showed impaired responses to anergizing stimuli. In anergic T cells, activated caspase 3 associated to the plasma membrane, where it cleaved and inactivated proteins such as the Grb2-related adaptor downstream of shc (GADS) and the guanine-nucleotide exchange factor Vav1, causing a blockade in TCR signaling. Our results identify a role for caspase 3 in nonapoptotic T cells and support that caspase 3-dependent proteolytic inactivation of signaling proteins is essential to maintain T cell tolerance.
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12
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Koenig A, Russell JQ, Rodgers WA, Budd RC. Spatial differences in active caspase-8 defines its role in T-cell activation versus cell death. Cell Death Differ 2008; 15:1701-11. [PMID: 18617900 PMCID: PMC2665918 DOI: 10.1038/cdd.2008.100] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Caspase-8, a cysteine-protease, initiates apoptosis when activated by death receptors. Caspase-8 is also essential for initiating T lymphocyte proliferation following T-cell antigen receptor (TCR) signaling. Given these disparate functions of caspase-8, we sought to determine whether this represented only a difference in the magnitude of caspase-8 activation, or different intracellular locations of active caspase-8. We demonstrate by high-resolution multicolor confocal laser scanning microscopy an aggregation of active caspase-8 within membrane lipid rafts in T cells stimulated with anti-CD3. This suggests that following TCR stimulation active caspase-8 physically interacts with lipid raft proteins, possibly to form a signaling platform. In contrast, Fas stimulation of T cells resulted in a much more profound activation of caspase-8 that was exclusively cytosolic. These confocal microscopic findings were confirmed using discontinuous sucrose gradient ultracentrifugation to isolate lipid raft versus cytosolic components. This sequestration model of caspase-8 activation was further supported by the observation that a classic caspase-8 substrate, BID, was not cleaved in CD3-stimulated T cells, but was cleaved after Fas engagement. Our data support a model that the location of active caspase-8 may profoundly influence its functional capacity as a regulator of either cell cycling or cell death.
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Affiliation(s)
- A Koenig
- Department of Medicine, Immunobiology Program, The University of Vermont College of Medicine, Burlington, VT 05405, USA.
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13
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Collins C, Shi C, Russell JQ, Fortner KA, Budd RC. Activation of gamma delta T cells by Borrelia burgdorferi is indirect via a TLR- and caspase-dependent pathway. THE JOURNAL OF IMMUNOLOGY 2008; 181:2392-8. [PMID: 18684928 DOI: 10.4049/jimmunol.181.4.2392] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Activation of the innate immune system typically precedes engagement of adaptive immunity. Cells at the interface between these two arms of the immune response are thus critical to provide full engagement of host defense. Among the innate T cells at this interface are gammadelta T cells. gammadelta T cells contribute to the defense from a variety of infectious organisms, yet little is understood regarding how they are activated. We have previously observed that human gammadelta T cells of the Vdelta1 subset accumulate in inflamed joints in Lyme arthritis and proliferate in response to stimulation with the causative spirochete, Borrelia burgdorferi. We now observe that murine gammadelta T cells are also activated by B. burgdorferi and that in both cases the activation is indirect via TLR stimulation on dendritic cells or monocytes. Furthermore, B. burgdorferi stimulation of monocytes via TLR, and secondary activation of gammadelta T cells, are both caspase-dependent.
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Affiliation(s)
- Cheryl Collins
- Immunobiology Program, Department of Medicine, The University of Vermont College of Medicine, Burlington, VT 50405, USA
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14
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Paulsen M, Ussat S, Jakob M, Scherer G, Lepenies I, Schütze S, Kabelitz D, Adam‐Klages S. Interaction with XIAP prevents full caspase‐3/‐7 activation in proliferating human T lymphocytes. Eur J Immunol 2008; 38:1979-87. [DOI: 10.1002/eji.200838211] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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15
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Sakowicz-Burkiewicz M, Nishanth G, Helmuth U, Drögemüller K, Busch DH, Utermöhlen O, Naumann M, Deckert M, Schlüter D. Protein Kinase C-θ Critically Regulates the Proliferation and Survival of Pathogen-Specific T Cells in Murine Listeriosis. THE JOURNAL OF IMMUNOLOGY 2008; 180:5601-12. [DOI: 10.4049/jimmunol.180.8.5601] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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16
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Hinshaw-Makepeace J, Huston G, Fortner KA, Russell JQ, Holoch D, Swain S, Budd RC. c-FLIP(S) reduces activation of caspase and NF-kappaB pathways and decreases T cell survival. Eur J Immunol 2008; 38:54-63. [PMID: 18081036 DOI: 10.1002/eji.200636956] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Effective stimulation of NF-kappaB in T cells following TCR ligation requires the activity of caspase-8. The active caspase-8 complex includes the paracaspase, MALT1, and Bcl-10, which connect to the NF-kappaB pathway. It has been less clear what regulates the level of caspase-8 activity during T cell activation. A likely candidate is cellular FLIP (c-FLIP), an enzymatically inert caspase-8 homologue. Two alternatively spliced forms of c-FLIP exist, a long form (c-FLIP(L)) and a short-form (c-FLIP(S)). The latter lacks the C-terminal caspase-like domain. c-FLIP(L) can heterodimerize with and activate caspase-8 through an activation loop in the C terminus of c-FLIP(L). Here we show that, in contrast to c-FLIP(L), c-FLIP(S) inhibits activation of caspase-8 in T cells, and consequently reduces recruitment of MALT1 and Bcl-10 to the active caspase complex. This results in reduced activity of NF-kappaB. Consequently, T cells from c-FLIP(S)-transgenic mice undergo more rapid cell death both spontaneously and after activation. The findings suggest that c-FLIP(S) functions to reduce the expansion of T cells during an immune response.
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Affiliation(s)
- Jennifer Hinshaw-Makepeace
- Immunobiology Program, Department of Medicine, The University of Vermont College of Medicine, Burlington, VT 05405-0068, USA
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17
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Rautajoki KJ, Kylaniemi MK, Raghav SK, Rao K, Lahesmaa R. An insight into molecular mechanisms of human T helper cell differentiation. Ann Med 2008; 40:322-35. [PMID: 18484344 DOI: 10.1080/07853890802068582] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Selective activation of T helper (Th) cell subsets plays an important role in immune response to pathogens as well as in the pathogenesis of human allergy and inflammatory diseases. Th1 cells along with the recently discovered Th17 cells play a role in the pathogenesis of autoimmune diseases. Th2 cytokines lead to series of inflammatory processes characteristic for asthma and other atopic diseases. To understand the pathogenesis of immune-mediated diseases it is crucial to dissect pathways and regulatory networks leading to the development of distinct Th subsets. Such knowledge may lead to better strategies for developing diagnostics and therapies for these diseases. The differentiation of Th1, Th2, and Th17 effector cells is driven by signals originating from T cell and costimulatory receptors as well as cytokines in the surroundings of activated naive T helper cells. There are several proteins involved in the regulation of this differentiation process. Most of the data on T helper cell differentiation have been acquired using mouse. In this review, we have summarized what is known about human T helper differentiation. In addition, selected differences between human and mouse will be discussed.
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Affiliation(s)
- Kirsi J Rautajoki
- Turku Centre for Biotechnology, University of Turku and Abo Akademi University, Turku, Finland
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18
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Brenner D, Golks A, Becker M, Müller W, Frey CR, Novak R, Melamed D, Kiefer F, Krammer PH, Arnold R. Caspase-cleaved HPK1 induces CD95L-independent activation-induced cell death in T and B lymphocytes. Blood 2007; 110:3968-77. [PMID: 17712048 DOI: 10.1182/blood-2007-01-071167] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Life and death of peripheral lymphocytes is strictly controlled to maintain physiologic levels of T and B cells. Activation-induced cell death (AICD) is one mechanism to delete superfluous lymphocytes by restimulation of their immunoreceptors and it depends partially on the CD95/CD95L system. Recently, we have shown that hematopoietic progenitor kinase 1 (HPK1) determines T-cell fate. While full-length HPK1 is essential for NF-kappaB activation in T cells, the C-terminal fragment of HPK1, HPK1-C, suppresses NF-kappaB and sensitizes toward AICD by a yet undefined cell death pathway. Here we show that upon IL-2-driven expansion of primary T cells, HPK1 is converted to HPK1-C by a caspase-3 activity below the threshold of apoptosis induction. HPK1-C selectively blocks induction of NF-kappaB-dependent antiapoptotic Bcl-2 family members but not of the proapoptotic Bcl-2 family member Bim. Interestingly, T and B lymphocytes from HPK1-C transgenic mice undergo AICD independently of the CD95/CD95L system but involving caspase-9. Knock down of HPK1/HPK1-C or Bim by small interfering RNA shows that CD95L-dependent and HPK1/HPK1-C-dependent cell death pathways complement each other in AICD of primary T cells. Our results define HPK1-C as a suppressor of antiapoptotic Bcl-2 proteins and provide a molecular basis for our understanding of CD95L-independent AICD of lymphocytes.
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Affiliation(s)
- Dirk Brenner
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
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19
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Abstract
During the course of an immune response, antigen-reactive T cells clonally expand and then are removed by apoptosis to maintain immune homeostasis. Life and death of T cells is determined by multiple factors, such as T-cell receptor triggering, co-stimulation or cytokine signalling, and by molecules, such as caspase-8 (FLICE)-like inhibitory protein (FLIP) and haematopoietic progenitor kinase 1 (HPK1), which regulate the nuclear factor-kappaB (NF-kappaB) pathway. Here, we discuss the concepts of activation-induced cell death (AICD) and activated cell-autonomous death (ACAD) in the regulation of life and death in T cells.
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Affiliation(s)
- Peter H Krammer
- Tumour Immunology Program, German Cancer Research Center, Im Neuenheimer Feld 280, D-69120 Heidelberg, Germany.
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20
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Taoufik E, Valable S, Müller GJ, Roberts ML, Divoux D, Tinel A, Voulgari-Kokota A, Tseveleki V, Altruda F, Lassmann H, Petit E, Probert L. FLIP(L) protects neurons against in vivo ischemia and in vitro glucose deprivation-induced cell death. J Neurosci 2007; 27:6633-46. [PMID: 17581950 PMCID: PMC6672692 DOI: 10.1523/jneurosci.1091-07.2007] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Knowledge of the molecular mechanisms that underlie neuron death after stroke is important to allow the development of effective neuroprotective strategies. In this study, we investigated the contribution of death receptor signaling pathways to neuronal death after ischemia using in vitro and in vivo models of ischemic injury and transgenic mice that are deficient in tumor necrosis factor receptor I (TNFRI KO) or show neuron-specific overexpression of the long isoform of cellular Fas-associated death domain-like interleukin-1-beta-converting enzyme-inhibitory protein (FLIP(L)). Caspase 8 was activated in brain lesions after permanent middle cerebral artery occlusion (pMCAO) and in cortical neurons subjected to glucose deprivation (GD) and was necessary for GD-induced neuron death. Thus, neurons treated with zIETD-FMK peptide or overexpressing a dominant-negative caspase 8 mutant were fully protected against GD-induced death. The presence of the neuroprotective TNFRI was necessary for selectively sustaining p50/p65NF-kappaB activity and the expression of the p43 cleavage form of FLIP(L), FLIP(p43), an endogenous inhibitor of caspase 8, in pMCAO lesions and GD-treated neurons. Moreover, TNF pretreatment further upregulated p50/p65NF-kappaB activity and FLIP(p43) expression in neurons after GD. The knock-down of FLIP in wild-type (WT) neurons using a short hairpin RNA revealed that FLIP(L) is essential for TNF/TNFRI-mediated neuroprotection after GD. Furthermore, the overexpression of FLIP(L) was sufficient to rescue TNFRI KO neurons from GD-induced death and to enhance TNF neuroprotection in WT neurons, and neuron-specific expression of FLIP(L) in transgenic mice significantly reduced lesion volume after pMCAO. Our results identify a novel role for the TNFRI-NF-kappaB-FLIP(L) pathway in neuroprotection after ischemia and identify potential new targets for stroke therapy.
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Affiliation(s)
- Era Taoufik
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Samuel Valable
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Georg J. Müller
- Division of Neuroimmunology, Brain Research Institute, A-1090 Vienna, Austria
| | | | - Didier Divoux
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Antoine Tinel
- Institute of Biochemistry, University of Lausanne, CH-1066 Epalinges, Switzerland, and
| | - Anda Voulgari-Kokota
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Vivian Tseveleki
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
| | - Fiorella Altruda
- Dipartimento di Genetica, Biologia e Biochimica, Universita di Torino, 10126 Torino, Italy
| | - Hans Lassmann
- Division of Neuroimmunology, Brain Research Institute, A-1090 Vienna, Austria
| | - Edwige Petit
- Universite de Caen, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 6185, 14074 Caen, France
| | - Lesley Probert
- Laboratory of Molecular Genetics, Hellenic Pasteur Institute, 11521 Athens, Greece
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Laiosa MD, Eckles KG, Langdon M, Rosenspire AJ, McCabe MJ. Exposure to inorganic mercury in vivo attenuates extrinsic apoptotic signaling in Staphylococcal aureus enterotoxin B stimulated T-cells. Toxicol Appl Pharmacol 2007; 225:238-50. [PMID: 17950395 DOI: 10.1016/j.taap.2007.06.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2007] [Revised: 05/31/2007] [Accepted: 06/01/2007] [Indexed: 01/19/2023]
Abstract
The heavy metal mercury (Hg) is known to have immunomodulatory properties affecting lymphocyte signal transduction, death receptor signaling and autoimmunity. In this study we tested the hypothesis that Hg exposure would attenuate T-cell activation and caspase 8 and 3 activity in response to antigenic stimuli. To test this hypothesis, BALB/cJ mice were exposed to 10 mg/l mercuric chloride (HgCl(2)) in their drinking water for 2 weeks followed by injection with 20 microg of the Staphylococcal aureus enterotoxin B (SEB) superantigen. Eighteen hours after SEB challenge, there was a statistically significant reduction in caspase 8 and caspase 3 enzyme activity in the SEB reactive Vbeta8+ T-cells. The attenuated caspase activity in Hg-exposed mice persisted for 48 h after exposure. Moreover, activation of caspase 8 and caspase 3 was reduced by more than 60% in CD95 deficient MRL/MpJ-Fas(lpr) mice demonstrating that caspase 8 and 3 activation in response to SEB is CD95 dependent. In addition to the effects of Hg on caspase activity, expression of the T-cell activation marker CD69 was also attenuated in SEB reactive Vbeta8 T-cells in Hg-exposed mice. Moreover, CD69 expression in MRL/MpJ-Fas(lpr) mice was also reduced. Taken together the caspase and CD69 data support a role for CD95 in promoting a proapoptotic and activated state in SEB responsive T-lymphocytes and this state is attenuated by the autoimmune potentiating environmental agent mercury.
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Affiliation(s)
- Michael D Laiosa
- Department of Environmental Medicine, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA
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22
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Misra RS, Russell JQ, Koenig A, Hinshaw-Makepeace JA, Wen R, Wang D, Huo H, Littman DR, Ferch U, Ruland J, Thome M, Budd RC. Caspase-8 and c-FLIPL associate in lipid rafts with NF-kappaB adaptors during T cell activation. J Biol Chem 2007; 282:19365-74. [PMID: 17462996 PMCID: PMC4521413 DOI: 10.1074/jbc.m610610200] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Humans and mice lacking functional caspase-8 in T cells manifest a profound immunodeficiency syndrome due to defective T cell antigen receptor (TCR)-induced NF-kappaB signaling and proliferation. It is unknown how caspase-8 is activated following T cell stimulation, and what is the caspase-8 substrate(s) that is necessary to initiate T cell cycling. We observe that following TCR ligation, a small portion of total cellular caspase-8 and c-FLIP(L) rapidly migrate to lipid rafts where they associate in an active caspase complex. Activation of caspase-8 in lipid rafts is followed by rapid cleavage of c-FLIP(L) at a known caspase-8 cleavage site. The active caspase.c-FLIP complex forms in the absence of Fas (CD95/APO1) and associates with the NF-kappaB signaling molecules RIP1, TRAF2, and TRAF6, as well as upstream NF-kappaB regulators PKC theta, CARMA1, Bcl-10, and MALT1, which connect to the TCR. The lack of caspase-8 results in the absence of MALT1 and Bcl-10 in the active caspase complex. Consistent with this observation, inhibition of caspase activity attenuates NF-kappaB activation. The current findings define a link among TCR, caspases, and the NF-kappaB pathway that occurs in a sequestered lipid raft environment in T cells.
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Affiliation(s)
- Ravi S. Misra
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont 05405-0068
| | - Jennifer Q. Russell
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont 05405-0068
| | - Andreas Koenig
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont 05405-0068
| | - Jennifer A. Hinshaw-Makepeace
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont 05405-0068
| | - Renren Wen
- Blood Research Institute, Department of Microbiology and Molecular Genetics, Blood Center of Wisconsin, Milwaukee, Wisconsin 53201-2178
| | - Demin Wang
- Blood Research Institute, Department of Microbiology and Molecular Genetics, Blood Center of Wisconsin, Milwaukee, Wisconsin 53201-2178
| | - Hairong Huo
- Howard Hughes Medical Institute, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, New York 10016
| | - Dan R. Littman
- Howard Hughes Medical Institute, Skirball Institute of Biomolecular Medicine, New York University School of Medicine, New York, New York 10016
| | - Uta Ferch
- Department of Medicine (Hematology/Oncology), Technical University of Munich, Munich, Germany
| | - Jurgen Ruland
- Department of Medicine (Hematology/Oncology), Technical University of Munich, Munich, Germany
| | - Margot Thome
- Institute of Biochemistry, University of Lausanne, BIL Biomedical Research Center, 1066 Epalinges, Switzerland
| | - Ralph C. Budd
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, Vermont 05405-0068
- To whom correspondence should be addressed: Given Medical Bldg., Burlington, VT 05405-0068. Tel.: 802-656-2286; Fax: 802-656-3854;
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DosReis GA, Ribeiro-Gomes FL, Guillermo LVC, Lopes MF. Cross-talk between apoptosis and cytokines in the regulation of parasitic infection. Cytokine Growth Factor Rev 2007; 18:97-105. [PMID: 17337235 DOI: 10.1016/j.cytogfr.2007.01.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Parasitic diseases have worldwide medical and economical impact. Host T lymphocytes and the cytokines they produce determine the outcome of parasitic infections. Programmed cell death by apoptosis is induced in the course of parasitic infections, and affects cytokine production by removing activated effector T and B cells. In addition, engulfment of apoptotic cells promotes the secretion of cytokines that regulate intracellular replication of protozoan parasites. In this review, we discuss how the cross-talk between apoptosis and cytokines regulates parasitic infection.
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Affiliation(s)
- George A DosReis
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Centro de Ciências da Saúde, Bloco G, Ilha do Fundão, Rio de Janeiro, RJ 21949-900, Brazil.
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24
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Guillermo LVC, Silva EM, Ribeiro-Gomes FL, De Meis J, Pereira WF, Yagita H, DosReis GA, Lopes MF. The Fas death pathway controls coordinated expansions of type 1 CD8 and type 2 CD4 T cells in Trypanosoma cruzi infection. J Leukoc Biol 2007; 81:942-51. [PMID: 17261545 DOI: 10.1189/jlb.1006643] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
We investigated the role of the Fas ligand (FasL)/Fas death pathway on apoptosis and cytokine production by T cells in Trypanosoma cruzi infection. Anti-FasL, but not anti-TNF-alpha or anti-TRAIL, blocked activation-induced cell death of CD8 T cells and increased secretion of IL-10 and IL-4 by CD4 T cells from T. cruzi-infected mice. CD4 and CD8 T cells up-regulated Fas/FasL expression during T. cruzi infection. However, Fas expression increased earlier in CD8 T cells, and a higher proportion of CD8 T cells was activated and expressed IFN-gamma compared with CD4 T cells. Injection of anti-FasL in infected mice reduced parasitemia and CD8 T cell apoptosis and increased the ratio of CD8:CD4 T cells recovered from spleen and peritoneum. FasL blockade increased the number of activated T cells, enhanced NO production, and reduced parasite loads in peritoneal macrophages. Injection of anti-FasL increased IFN-gamma secretion by splenocytes responding to T. cruzi antigens but also exacerbated production of type 2 cytokines IL-10 and IL-4 at a late stage of acute infection. These results indicate that the FasL/Fas death pathway regulates apoptosis and coordinated cytokine responses by type 1 CD8 and type 2 CD4 T cells in T. cruzi infection.
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Affiliation(s)
- Landi V Costilla Guillermo
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Av. Carlos Chagas Filho, Ilha do Fundão, Rio de Janeiro, RJ, 21941-902, Brazil
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25
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Arnold R, Frey CR, Müller W, Brenner D, Krammer PH, Kiefer F. Sustained JNK signaling by proteolytically processed HPK1 mediates IL-3 independent survival during monocytic differentiation. Cell Death Differ 2006; 14:568-75. [PMID: 17024227 DOI: 10.1038/sj.cdd.4402042] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
We studied monocytic differentiation of primary mouse progenitor cells to understand molecular mechanisms of differentiation. We found a tightly controlled non-apoptotic activation of caspase-3 that correlated with differentiation. Although caspase activity was already detected during monocytic differentiation, a caspase-3 target has not been identified yet. We show that hematopoietic progenitor kinase 1 (HPK1) is processed towards its N- and C-terminal fragments during monocytic differentiation. While HPK1 is an immunoreceptor-proximal kinase in T and B cells, its role in myeloid cells is elusive. Here, we show that the N-terminal cleavage product, HPK1-N, comprising the kinase domain, confers progenitor cell survival independent of the growth factor IL-3. Furthermore, HPK1-N causes differentiation of progenitor cells towards the monocytic lineage. In contrast to full-length kinase, HPK1-N is constitutively active causing sustained JNK activation, Bad phosphorylation and survival. Blocking of caspase activity during differentiation of primary mouse progenitor cells leads to reduced HPK1-N levels, suppressed JNK activity and attenuated monocytic differentiation. Our work explains growth factor-independent survival during monocytic differentiation by caspase-mediated processing of HPK1 towards HPK1-N.
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Affiliation(s)
- R Arnold
- Max-Planck-Institute for Physiological and Clinical Research, WG Kerckhoff-Institute, Parkstrasse 1, D-61231 Bad Nauheim, Germany.
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26
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Huber S, Dohrman A, Sartini D, Budd RC. Reduced myocarditis following Coxsackievirus infection in cellular FLICE inhibitory protein--long form-transgenic mice. Immunology 2006; 119:541-50. [PMID: 17010108 PMCID: PMC2265828 DOI: 10.1111/j.1365-2567.2006.02469.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Cellular FLICE inhibitory protein--long form (c-FLIP(L)) is a caspase-defective homologue of caspase-8 that blocks apoptosis by death receptors. c-FLIP(L) expression in T cells can also augment activation of the mitogen-activated protein kinase, extracellular signal-related kinase, as well as nuclear factor-kappaB. This contributes to increased production of interleukin-2 and CD25, resulting in hyperproliferation of T cells from c-FLIP(L)-transgenic mice. c-FLIP also heterodimerizes with and activates caspase-8, resulting in increased death of T cells and a selection of a T helper 2 cytokine profile. The effects of c-FLIP on cytolytic function of CD8(+) T cells have not been examined previously. We studied the cytolytic capacity of T cells from c-FLIP(L)-transgenic mice using an antigen-specific system, as well as the consequences during a viral immune response to Coxsackievirus B3 (CVB3). The increased T-cell receptor (TCR) signalling due to c-FLIP did not alter the cytolytic machinery but did reduce cytotoxicity because of decreased surface expression of TCR and CD8. It also produced a Tc2 cytokine profile. These effects of c-FLIP collectively served to diminish the severity of CVB3-induced myocarditis.
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Affiliation(s)
- Sally Huber
- Department of Pathology, The University of Vermont College of Medcine, Burlington, VT, USA
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27
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Arnold R, Brenner D, Becker M, Frey CR, Krammer PH. How T lymphocytes switch between life and death. Eur J Immunol 2006; 36:1654-8. [PMID: 16791883 DOI: 10.1002/eji.200636197] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
While insufficient cell death of activated T cells can result in autoimmune disorders, elimination of too many T cells can lead to immunodeficiency. Therefore, T lymphocyte fate is highly regulated and requires that cells can switch from an apoptosis-resistant towards an apoptosis-sensitive state. This switch is tightly controlled by various effector molecules. Basically, two separate pathways control the fate of antigen-activated T cells: activation-induced cell death (AICD) and activated T cell autonomous death (ACAD). Autoreactive T lymphocytes are eliminated by restimulation via their T cell receptor (TCR) and undergo AICD involving death receptors (extrinsic pathway). In contrast, ACAD can lead to T cell deletion without TCR restimulation, and is determined by the ratio between anti- and pro-apoptotic Bcl-2 family members at the mitochondria (intrinsic pathway). While the extrinsic and the intrinsic pathway lead to caspase activation, non-caspase proteases (e.g., cathepsins) can be released by the lysosomes and might contribute to AICD as well as to ACAD. Activated T cells poses cell death escape mechanisms which are needed for survival of (memory) T cells, but are deleterious for autoimmune disorders or progression of T cell lymphomas.
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Affiliation(s)
- Rüdiger Arnold
- Tumor Immunology Program, German Cancer Research Center, Heidelberg, Germany.
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28
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Farley N, Pedraza-Alva G, Serrano-Gomez D, Nagaleekar V, Aronshtam A, Krahl T, Thornton T, Rincón M. p38 mitogen-activated protein kinase mediates the Fas-induced mitochondrial death pathway in CD8+ T cells. Mol Cell Biol 2006; 26:2118-29. [PMID: 16507991 PMCID: PMC1430304 DOI: 10.1128/mcb.26.6.2118-2129.2006] [Citation(s) in RCA: 65] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The p38 mitogen-activated protein kinase (MAPK) signaling pathway can be activated by a variety of stress stimuli such as UV radiation and osmotic stress. The regulation and role of this pathway in death receptor-induced apoptosis remain unclear and may depend on the specific death receptor and cell type. Here we show that binding of Fas ligand to Fas activates p38 MAPK in CD8+ T cells and that activation of this pathway is required for Fas-mediated CD8+ T-cell death. Active p38 MAPK phosphorylates Bcl-xL and Bcl-2 and prevents the accumulation of these antiapoptotic molecules within the mitochondria. Consequently, a loss of mitochondrial membrane potential and the release of cytochrome c lead to the activation of caspase 9 and, subsequently, caspase 3. Therefore, the activation of p38 MAPK is a critical link between Fas and the mitochondrial death pathway and is required for the Fas-induced apoptosis of CD8+ T cells.
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Affiliation(s)
- Nicholas Farley
- Department of Medicine/Immunobiology Program, Given Medical Building D305, University of Vermont, Burlington, VT 05405, USA
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29
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Golks A, Brenner D, Krammer PH, Lavrik IN. The c-FLIP-NH2 terminus (p22-FLIP) induces NF-kappaB activation. ACTA ACUST UNITED AC 2006; 203:1295-305. [PMID: 16682493 PMCID: PMC2121210 DOI: 10.1084/jem.20051556] [Citation(s) in RCA: 165] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
c-FLIP proteins (isoforms: c-FLIPL, c-FLIPS, and c-FLIPR) play an essential role in the regulation of death receptor–induced apoptosis. Here, we demonstrate that the cytoplasmic NH2-terminal procaspase-8 cleavage product of c-FLIP (p22-FLIP) found in nonapoptotic malignant cells, primary T and B cells, and mature dendritic cells (DCs) strongly induces nuclear factor κB (NF-κB) activity by interacting with the IκB kinase (IKK) complex via the IKKγ subunit. Thus, in addition to inhibiting apoptosis by binding to the death-inducing signaling complex, our data demonstrate a novel mechanism by which c-FLIP controls NF-κB activation and life/death decisions in lymphocytes and DCs.
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Affiliation(s)
- Alexander Golks
- Division of Immunogenetics, Tumorimmunology Program, German Cancer Research Center, D-69120 Heidelberg, Germany
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30
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Abstract
Cellular caspase-8 (FLICE)-like inhibitory protein (cFLIP) was originally identified as an inhibitor of death-receptor signalling through competition with caspase-8 for recruitment to FAS-associated via death domain (FADD). More recently, it has been determined that both cFLIP and caspase-8 are required for the survival and proliferation of T cells following T-cell-receptor stimulation. This paradoxical finding launched new investigations of how these molecules might connect with signalling pathways that link to cell survival and growth following antigen-receptor activation. As discussed in this Review, insight gained from these studies indicates that cFLIP and caspase-8 form a heterodimer that ultimately links T-cell-receptor signalling to activation of nuclear factor-kappaB through a complex that includes B-cell lymphoma 10 (BCL-10), mucosa-associated-lymphoid-tissue lymphoma-translocation gene 1 (MALT1) and receptor-interacting protein 1 (RIP1).
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Affiliation(s)
- Ralph C Budd
- Immunobiology Program, Department of Medicine, The University of Vermont College of Medicine, Burlington, Vermont 50405, USA
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31
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Arechiga AF, Bell BD, Solomon JC, Chu IH, Dubois CL, Hall BE, George TC, Coder DM, Walsh CM. Cutting edge: FADD is not required for antigen receptor-mediated NF-kappaB activation. THE JOURNAL OF IMMUNOLOGY 2006; 175:7800-4. [PMID: 16339514 DOI: 10.4049/jimmunol.175.12.7800] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Recently, it has been demonstrated that stimulated T cells bearing defects in caspase-8 fail to promote nuclear shuttling of NF-kappaB complexes. Such cells display strikingly similar proliferative and survival defects as T cells lacking Fas-associated death domain protein (FADD) function. We characterized NF-kappaB signaling in T cells bearing a dominant-negative FADD transgene (FADDdd). Whereas FADDdd T cells displayed proliferative defects following activation, these were not a consequence of aberrant NF-kappaB signaling, as measured by IKK/IkappaB phosphorylation and IkappaB degradation. There were no appreciable defects in nuclear translocation of p65/Rel using ImageStream, a flow-based imaging cytometer. Pretreatment with benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone, a potent caspase inhibitor, also failed to impede canonical NF-kappaB signaling. Secretion of IL-2 and up-regulation of various activation markers occurred normally. Thus, FADD does not play an essential role in NF-kappaB activation, suggesting an alternative route by which this adaptor promotes the clonal expansion of T cells.
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Affiliation(s)
- Adrian F Arechiga
- Center for Immunology and Department of Molecular Biology & Biochemistry, University of California, Irvine. CA 92697, USA
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32
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Wu W, Misra RS, Russell JQ, Flavell RA, Rincón M, Budd RC. Proteolytic regulation of nuclear factor of activated T (NFAT) c2 cells and NFAT activity by caspase-3. J Biol Chem 2006; 281:10682-90. [PMID: 16455648 DOI: 10.1074/jbc.m511759200] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The nuclear factor of activated T (NFAT) cell family of transcription factors is important in regulating the expression of a broad array of genes, including cytokines, T cell surface receptors, and other transcription factors. NFATc1 and NFATc2 are two principal NFAT members that are expressed in peripheral T cells. Levels of NFAT expression in T cells are partly transcriptionally regulated, but less is understood regarding their post-transcriptional control. We show here that NFATc1 and NFATc2 are rapidly degraded in apoptotic T cells. NFATc2 is highly sensitive to cleavage by caspase-3, whereas NFATc1 is only weakly sensitive to caspase-3 or caspase-8. Two potential caspase-3 cleavage sites were identified in the N-terminal transactivation domain. These sites were confirmed by in vitro caspase cleavage assays. Abolition of NFATc2 cleavage by mutation of these two cleavage sites resulted in augmented NFAT transcriptional activity. Furthermore, NFAT activity could be augmented in wild-type effector T cells by inhibition of caspase activity. Of particular interest was that non-apoptotic T cells from cellular FLIP long transgenic (c-FLIP(L)-Tg) mice that manifest elevated caspase activity have greatly reduced levels of NFATc2 protein and NFAT transcriptional activity. Our findings reveal a new post-transcriptional regulation of NFATc2 that operates, not only during apoptosis, but also in non-apoptotic effector T cells.
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Affiliation(s)
- Wenfang Wu
- Immunobiology Program, Department of Medicine, The University of Vermont College of Medicine, Burlington, Vermont 05405, USA
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33
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Brenner D, Golks A, Kiefer F, Krammer PH, Arnold R. Activation or suppression of NFkappaB by HPK1 determines sensitivity to activation-induced cell death. EMBO J 2005; 24:4279-90. [PMID: 16341093 PMCID: PMC1356335 DOI: 10.1038/sj.emboj.7600894] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2005] [Accepted: 11/09/2005] [Indexed: 12/16/2022] Open
Abstract
Restimulation of the T-cell receptor (TCR) in activated T cells induces CD95 (Fas/Apo-1)-mediated activation-induced cell death (AICD). The TCR-proximal mechanisms leading to AICD are elusive. Here we characterize hematopoietic progenitor kinase 1 (HPK1) as a differentially regulated TCR-proximal signaling protein involved in AICD of primary T cells. We show that HPK1 is a functional component of the endogenous IkappaB kinase (IKK) complex and is crucial for TCR-mediated NFkappaB activation. While full-length HPK1 enhances IKKbeta phosphorylation, siRNA-mediated knockdown of HPK1 blunts TCR-mediated NFkappaB activation and increases cell death. We also demonstrate proteolytic processing of HPK1 into HPK1-C, specifically in AICD-sensitive primary T cells. The cleavage product HPK1-C sequesters the inactive IKK complex and suppresses NFkappaB upon TCR restimulation by binding to IKKalpha and IKKbeta. T cells of HPK1-C transgenic mice are sensitized towards TCR-mediated AICD. Consequently, preventing HPK1-C generation in primary T cells by siRNA-mediated knockdown results in decreased AICD. Thus, these results show a novel mechanism of sensitization of T lymphocytes towards AICD by suppression of NFkappaB, and propose that HPK1 is a life/death switch in T lymphocytes.
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Affiliation(s)
- Dirk Brenner
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Alexander Golks
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | | | - Peter H Krammer
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Rüdiger Arnold
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Heidelberg, Germany
- Tumor Immunology Program, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 280, 69112 Heidelberg, Germany. Tel.: +49 6221 423769; Fax: +49 6221 411715; E-mail:
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Maksimow M, Söderström TS, Jalkanen S, Eriksson JE, Hänninen A. Fas costimulation of naive CD4 T cells is controlled by NF-kappaB signaling and caspase activity. J Leukoc Biol 2005; 79:369-77. [PMID: 16330535 DOI: 10.1189/jlb.0505238] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Fas ligation induces apoptosis of activated T cells via the caspase cascade but can also mediate costimulatory signals to naïve T cells at the time of activation. We have previously shown that Fas ligation of naïve CD4 T cells activated by dendritic cells induces death or accelerates their proliferation and increases interferon-gamma (IFN-gamma) production. To understand this costimulation, we investigated the roles of caspases and nuclear factor (NF)-kappaB in survival and proliferation of responding T cells. Fas ligation increased caspase-3 and -8 activities during T cell activation, irrespective of cell fate. The accelerated proliferation induced by Fas ligation could be reduced by selective inhibition of both caspases. Inhibition of NF-kappaB simultaneously with Fas ligation inhibited the increased IFN-gamma production and caused uniform death of all responding T cells. Thus, Fas-mediated costimulation of naïve CD4 T cells is driven by active caspases, and NF-kappaB acts as a dominant survival-supporting factor of Fas-costimulated cells containing high levels of activated caspase-8 and -3.
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35
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Paananen A, Järvinen K, Sareneva T, Salkinoja-Salonen MS, Timonen T, Hölttä E. Valinomycin-induced apoptosis of human NK cells is predominantly caspase independent. Toxicology 2005; 212:37-45. [PMID: 15876477 DOI: 10.1016/j.tox.2005.04.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2005] [Revised: 03/31/2005] [Accepted: 04/04/2005] [Indexed: 11/25/2022]
Abstract
Human NK cells are sensitive to the exogenous toxic compound valinomycin. This toxin, produced by Streptomyces griseus in moisture damaged buildings, induces apoptosis by dissipating the membrane potential in mitochondria. In this paper, we show that valinomycin-induced apoptosis involves two different pathways in human NK cells: the predominant one is caspase-3 independent and the other caspase-3 dependent. Resting human NK cells were found to contain high amounts of active caspase-3 as compared to the T cells in which high caspase-3 activity has been shown only after stimulation. Exposure to valinomycin did not alter the caspase-3 activity of human NK cells but induced nucleosomal fragmentation of DNA. General caspase inhibitor, Z-VAD-FMK, inhibited completely the caspase-3 activity, reduced DNA cleavage but did not prevent the spontaneous or valinomycin-induced apoptosis of NK cells. The endogenous high caspase-3 had only a slight effect on the major functions of human NK cells, i.e. cytotoxicity or gamma-IFN production, giving us a reason to suspect that the biological role of caspase-3 in NK cells could be the elimination of potentially harmful NK clones through apoptosis.
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Affiliation(s)
- Auli Paananen
- Department of Pathology, Haartman Institute, University of Helsinki, P.O. Box 21, FIN-00014 Helsinki, Finland
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Dohrman A, Russell JQ, Cuenin S, Fortner K, Tschopp J, Budd RC. Cellular FLIP Long Form Augments Caspase Activity and Death of T Cells through Heterodimerization with and Activation of Caspase-8. THE JOURNAL OF IMMUNOLOGY 2005; 175:311-8. [PMID: 15972663 DOI: 10.4049/jimmunol.175.1.311] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Caspase activity is required not only for the death of T cells, but also for their activation. A delicate balance of caspase activity is thus required during T cell activation at a level that will not drive cell death. How caspase activity is initiated and regulated during T cell activation is not known. One logical candidate for this process is cellular FLIP long form (c-FLIP(L)), because it can block caspase-8 recruitment after Fas (CD95) ligation as well as directly heterodimerize with and activate caspase-8. The current findings demonstrate that after T cell activation, caspase-8 and c-FLIP(L) associate in a complex enriched for active caspases. This occurs coincidently with the cleavage of two known caspase-8 substrates, c-FLIP(L) and receptor interacting protein 1. Caspase activity is higher in wild-type CD8(+) than CD4(+) effector T cells. Increased expression of c-FLIP(L) results in augmented caspase activity in resting and effector T cells to levels that provoke cell death, especially of the CD8 subset. c-FLIP(L) is thus not only an inhibitor of cell death by Fas, it can also act as a principal activator of caspases independently of Fas.
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Affiliation(s)
- Austin Dohrman
- Immunobiology Program, Department of Medicine, University of Vermont College of Medicine, Burlington, VT 05405, USA
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