Tumor Necrosis Factor Decoy Receptors: A subclass of tumor necrosis family receptors that lack cell signaling domains. They bind to specific TNF RECEPTOR LIGANDS and are believed to play a modulating role in the TNF signaling pathway. Some of the decoy receptors are products of distinct genes, while others are products of ALTERNATIVE SPLICING of the MRNA for the active receptor.Tumor Necrosis Factor-alpha: Serum glycoprotein produced by activated MACROPHAGES and other mammalian MONONUCLEAR LEUKOCYTES. It has necrotizing activity against tumor cell lines and increases ability to reject tumor transplants. Also known as TNF-alpha, it is only 30% homologous to TNF-beta (LYMPHOTOXIN), but they share TNF RECEPTORS.Receptors, Tumor Necrosis Factor, Member 6b: A secreted tumor necrosis factor receptor family member that has specificity FAS LIGAND and TUMOR NECROSIS FACTOR LIGAND SUPERFAMILY MEMBER 14. It plays a modulating role in tumor necrosis factor signaling pathway.Receptors, Tumor Necrosis Factor: Cell surface receptors that bind TUMOR NECROSIS FACTORS and trigger changes which influence the behavior of cells.Receptors, Tumor Necrosis Factor, Type I: A tumor necrosis factor receptor subtype that has specificity for TUMOR NECROSIS FACTOR ALPHA and LYMPHOTOXIN ALPHA. It is constitutively expressed in most tissues and is a key mediator of tumor necrosis factor signaling in the vast majority of cells. The activated receptor signals via a conserved death domain that associates with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.Receptors, Tumor Necrosis Factor, Type II: A tumor necrosis factor receptor subtype that is expressed primarily in IMMUNE SYSTEM cells. It has specificity for membrane-bound form of TUMOR NECROSIS FACTORS and mediates intracellular-signaling through TNF RECEPTOR ASSOCIATED FACTORS.Necrosis: The pathological process occurring in cells that are dying from irreparable injuries. It is caused by the progressive, uncontrolled action of degradative ENZYMES, leading to MITOCHONDRIAL SWELLING, nuclear flocculation, and cell lysis. It is distinct it from APOPTOSIS, which is a normal, regulated cellular process.Interleukin-1: A soluble factor produced by MONOCYTES; MACROPHAGES, and other cells which activates T-lymphocytes and potentiates their response to mitogens or antigens. Interleukin-1 is a general term refers to either of the two distinct proteins, INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The biological effects of IL-1 include the ability to replace macrophage requirements for T-cell activation.Cytokines: Non-antibody proteins secreted by inflammatory leukocytes and some non-leukocytic cells, that act as intercellular mediators. They differ from classical hormones in that they are produced by a number of tissue or cell types rather than by specialized glands. They generally act locally in a paracrine or autocrine rather than endocrine manner.Osteoprotegerin: A secreted member of the TNF receptor superfamily that negatively regulates osteoclastogenesis. It is a soluble decoy receptor of RANK LIGAND that inhibits both CELL DIFFERENTIATION and function of OSTEOCLASTS by inhibiting the interaction between RANK LIGAND and RECEPTOR ACTIVATOR OF NUCLEAR FACTOR-KAPPA B.NF-kappa B: Ubiquitous, inducible, nuclear transcriptional activator that binds to enhancer elements in many different cell types and is activated by pathogenic stimuli. The NF-kappa B complex is a heterodimer composed of two DNA-binding subunits: NF-kappa B1 and relA.Cells, Cultured: Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.TNF-Related Apoptosis-Inducing Ligand: A transmembrane-protein belonging to the TNF family of intercellular signaling proteins. It is a widely expressed ligand that activates APOPTOSIS by binding to TNF-RELATED APOPTOSIS-INDUCING LIGAND RECEPTORS. The membrane-bound form of the protein can be cleaved by specific CYSTEINE ENDOPEPTIDASES to form a soluble ligand form.Tumor Necrosis Factors: A family of proteins that were originally identified by their ability to cause NECROSIS of NEOPLASMS. Their necrotic effect on cells is mediated through TUMOR NECROSIS FACTOR RECEPTORS which induce APOPTOSIS.Apoptosis: One of the mechanisms by which CELL DEATH occurs (compare with NECROSIS and AUTOPHAGOCYTOSIS). Apoptosis is the mechanism responsible for the physiological deletion of cells and appears to be intrinsically programmed. It is characterized by distinctive morphologic changes in the nucleus and cytoplasm, chromatin cleavage at regularly spaced sites, and the endonucleolytic cleavage of genomic DNA; (DNA FRAGMENTATION); at internucleosomal sites. This mode of cell death serves as a balance to mitosis in regulating the size of animal tissues and in mediating pathologic processes associated with tumor growth.Receptors, CCR10: CCR receptors with specificity for CHEMOKINE CCL27. They may play a specialized role in the cutaneous homing of LYMPHOCYTES.RNA, Messenger: RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.Lipopolysaccharides: Lipid-containing polysaccharides which are endotoxins and important group-specific antigens. They are often derived from the cell wall of gram-negative bacteria and induce immunoglobulin secretion. The lipopolysaccharide molecule consists of three parts: LIPID A, core polysaccharide, and O-specific chains (O ANTIGENS). When derived from Escherichia coli, lipopolysaccharides serve as polyclonal B-cell mitogens commonly used in laboratory immunology. (From Dorland, 28th ed)Receptors, TNF-Related Apoptosis-Inducing Ligand: Tumor necrosis factor receptor family members that are widely expressed and play a role in regulation of peripheral immune responses and APOPTOSIS. The receptors are specific for TNF-RELATED APOPTOSIS-INDUCING LIGAND and signal via conserved death domains that associate with specific TNF RECEPTOR-ASSOCIATED FACTORS in the CYTOPLASM.Interleukin-6: A cytokine that stimulates the growth and differentiation of B-LYMPHOCYTES and is also a growth factor for HYBRIDOMAS and plasmacytomas. It is produced by many different cells including T-LYMPHOCYTES; MONOCYTES; and FIBROBLASTS.Signal Transduction: The intracellular transfer of information (biological activation/inhibition) through a signal pathway. In each signal transduction system, an activation/inhibition signal from a biologically active molecule (hormone, neurotransmitter) is mediated via the coupling of a receptor/enzyme to a second messenger system or to an ion channel. Signal transduction plays an important role in activating cellular functions, cell differentiation, and cell proliferation. Examples of signal transduction systems are the GAMMA-AMINOBUTYRIC ACID-postsynaptic receptor-calcium ion channel system, the receptor-mediated T-cell activation pathway, and the receptor-mediated activation of phospholipases. Those coupled to membrane depolarization or intracellular release of calcium include the receptor-mediated activation of cytotoxic functions in granulocytes and the synaptic potentiation of protein kinase activation. Some signal transduction pathways may be part of larger signal transduction pathways; for example, protein kinase activation is part of the platelet activation signal pathway.Receptors, Interleukin-1 Type II: An interleukin-1 receptor subtype that competes with the INTERLEUKIN-1 RECEPTOR TYPE I for binding to INTERLEUKIN-1ALPHA and INTERLEUKIN-1BETA. The interleukin-1 type II receptor appears to lack signal transduction capability. Therefore it may act as a "decoy" receptor that modulates the activity of its ligands. Both membrane-bound and soluble forms of the receptor have been identified.Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Lymphotoxin-alpha: A tumor necrosis factor family member that is released by activated LYMPHOCYTES. Soluble lymphotoxin is specific for TUMOR NECROSIS FACTOR RECEPTOR TYPE I; TUMOR NECROSIS FACTOR RECEPTOR TYPE II; and TUMOR NECROSIS FACTOR RECEPTOR SUPERFAMILY, MEMBER 14. Lymphotoxin-alpha can form a membrane-bound heterodimer with LYMPHOTOXIN-BETA that has specificity for the LYMPHOTOXIN BETA RECEPTOR.Mice, Inbred C57BLCell Line: Established cell cultures that have the potential to propagate indefinitely.Receptor Activator of Nuclear Factor-kappa B: A tumor necrosis factor receptor family member that is specific for RANK LIGAND and plays a role in bone homeostasis by regulating osteoclastogenesis. It is also expressed on DENDRITIC CELLS where it plays a role in regulating dendritic cell survival. Signaling by the activated receptor occurs through its association with TNF RECEPTOR-ASSOCIATED FACTORS.Apoptosis Regulatory Proteins: A large group of proteins that control APOPTOSIS. This family of proteins includes many ONCOGENE PROTEINS as well as a wide variety of classes of INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS such as CASPASES.Cell Line, Tumor: A cell line derived from cultured tumor cells.