ABSTRACT: PCR array of inflammatory cytokines and receptors in mouse lungs with NF-kappaB RelA mutant in alveolar epithelial cells during LPS stimulation
Project description:A murine model of RelA mutated throughout the alveolar epithelium was generated. Mice were anesthetized and intratracheally instilled with 50M-NM-<g LPS into the left lung lobe. Mice were euthanized after 6 hours after instillation, and left lung lobes were collected to isolate RNA. We used SABioscience Mouse Inflammatory Cytokines and Receptors PCR Array to evaluate whether the expressions of lung cytokines and receptors during LPS stimulation are dependent on alveolar epithelial NF-M-NM-:B RelA or not. qPCR gene expression profiling. RNA were collected from six different mouse lungs in each genotype (wild-type and alveolar epithelial RelA mutant). Equal amount of RNA (200ng) was pooled from six different mouse lungs, and 1M-NM-<g of total RNA (1.2M-NM-<g) was used to the PCR array.
Project description:A murine model of RelA mutated throughout the alveolar epithelium was generated. Mice were anesthetized and intratracheally instilled with 50μg LPS into the left lung lobe. Mice were euthanized after 6 hours after instillation, and left lung lobes were collected to isolate RNA. We used SABioscience Mouse Inflammatory Cytokines and Receptors PCR Array to evaluate whether the expressions of lung cytokines and receptors during LPS stimulation are dependent on alveolar epithelial NF-κB RelA or not.
Project description:A murine model of RelA mutated throughout the alveolar epithelium was generated. Mice were anesthetized and intratracheally instilled with 106 CFU of Streptococcus pneumoniae serotype 3 into the left lung lobe. Mice were euthanized after 15 hours after instillation, and left lung lobes were collected to isolate RNA. We used SABioscience Mouse Inflammatory Cytokines and Receptors PCR Array to evaluate whether the expressions of lung cytokines and receptors during pneumococcal pneumonia are dependent on alveolar epithelial NF-M-NM-:B RelA or not. qPCR gene expression profiling. RNA were collected from six different mouse lungs in each genotype (wild-type and alveolar epithelial RelA mutant). Equal amount of RNA (200ng) was pooled from six different mouse lungs, and 1M-NM-<g of total RNA (1.2M-NM-<g) was used to the PCR array.
Project description:PCR array of inflammatory cytokines and receptors in mouse lungs with NF-kappaB RelA mutant in alveolar epithelial cells during pneumococcal pneumonia
Project description:A murine model of RelA mutated throughout the alveolar epithelium was generated. Mice were anesthetized and intratracheally instilled with 106 CFU of Streptococcus pneumoniae serotype 3 into the left lung lobe. Mice were euthanized after 15 hours after instillation, and left lung lobes were collected to isolate RNA. We used SABioscience Mouse Inflammatory Cytokines and Receptors PCR Array to evaluate whether the expressions of lung cytokines and receptors during pneumococcal pneumonia are dependent on alveolar epithelial NF-κB RelA or not.
Project description:The NF-KappaB family of transcription factors plays a critical role in numerous cellular processes, particularly the immune response. Our understanding of how the different NF-kappaB subunits act coordinately to regulate gene expression is based on a limited set of genes. We used genome-scale location analysis to identify targets of all five NF-kappaB proteins before and after stimulation of monocytic cells with bacterial lipopolysaccharide (LPS). In unstimulated cells, p50 and p52 bound to a significant number of gene promoters. p50 occupied genes together with RNA polymerase II and defined a set of genes to which other NF-kappaB proteins bound after LPS induction. In stimulated cells, genes bound by multiple NF-kappaB subunits exhibited the greatest increases in RNA polymerase II occupancy and gene expression. This study identifies novel NF-kappaB target genes, reveals how the different NF-kappaB proteins coordinate their activity and maps transcriptional regulatory networks that underlie the host response to infection.
Project description:Classical Hodgkin lymphoma (cHL) is one of the most common malignant lymphomas. It is characterized by the presence of rare Hodgkin and Reed/Sternberg (HRS) cells embedded in an extensive inflammatory infiltrate. Constitutive activation of nuclear factor-kappaB (NF-kappaB) in HRS cells which transcriptionally regulates expression of multiple anti-apoptotic factors and pro-inflammatory cytokines plays a central role in the pathogenesis of cHL (1, 2). In non-stimulated condition, NF-kappaB proteins are rendered inactive by binding to their inhibitors (IkappaB s), which sequester them in the cytoplasm. Stimulation of multiple receptors activates the IkappaB kinase (IKK) complex that phosphorylates IkappaB at two specific serine residues, followed by its ubiquitination and proteasomal degradation, thereby releasing NF-kappaB proteins and allowing their nuclear translocation (3). Recently, two studies provided further insights into the molecular mechanisms of IKK activation upon TNF stimulation (4, 5). Activation of the IKK complex and subsequent NF-kappaB activation requires Lys63 polyubiquitination of RIP1, a kinase which is recruited to the receptor upon TNF stimulation. IKK-gamma (NEMO), the regulatory subunit of the IKK complex, specifically recognizes these Lys63-linked polyubiquitins attached to RIP1 and thereby activates IKK and NF-kappaB (4, 5). A20 is an ubiquitin-modifying enzyme that inhibits NF-kappaB activation in succession of tumor necrosis factor (TNF) receptor and Toll-like receptor induced signals (6-8). This enzyme removes Lys63 linked ubiquitin chains from RIP1 and adds Lys48 polyubiquitins to RIP1, thereby targeting this factor for proteasomal degradation, thus explaining the molecular mechanism of NF-kappaB inhibition by A20 (6). A20 likely inhibits NF-kappaB acitivity also by additional means, including interaction with TRAF1 and TRAF2 (9).
Project description:The bacterial product lipopolysaccharide (LPS) stimulates nuclear factor kB (NF-kB) signaling, which results in the production of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), as part of the immune response. NF-kB target genes also include those encoding proteins that inhibit NF-kB signaling through negative feedback loops. By simultaneously studying the dynamics of the nuclear translocation of the NF-kB subunit RelA and the activity of a Tnf-driven reporter in a mouse macrophage cell line, Sung et al. found that the gene encoding RelA was also a target of NF-kB. Synthesis of RelA occurred only at higher concentrations of LPS and constituted a positive feedback loop that dominated over existing negative feedback mechanisms. Genes expressed in response to a high concentration of LPS were enriched for those involved in innate immune responses. Together, these data suggest that the RelA-dependent positive feedback loop enables macrophages to mount an effective immune only above a critical concentration of LPS. Bone-marrow-derived macrophage (BMDM) cells were stimulated with zero, low, and high concentration of LPS separately for 4hrs. Two replicates for each condition.
Project description:Classical Hodgkin lymphoma (cHL) is one of the most common malignant lymphomas. It is characterized by the presence of rare Hodgkin and Reed/Sternberg (HRS) cells embedded in an extensive inflammatory infiltrate. Constitutive activation of nuclear factor-kappaB (NF-kappaB) in HRS cells which transcriptionally regulates expression of multiple anti-apoptotic factors and pro-inflammatory cytokines plays a central role in the pathogenesis of cHL (1, 2). In non-stimulated condition, NF-kappaB proteins are rendered inactive by binding to their inhibitors (IkappaB s), which sequester them in the cytoplasm. Stimulation of multiple receptors activates the IkappaB kinase (IKK) complex that phosphorylates IkappaB at two specific serine residues, followed by its ubiquitination and proteasomal degradation, thereby releasing NF-kappaB proteins and allowing their nuclear translocation (3). Recently, two studies provided further insights into the molecular mechanisms of IKK activation upon TNF stimulation (4, 5). Activation of the IKK complex and subsequent NF-kappaB activation requires Lys63 polyubiquitination of RIP1, a kinase which is recruited to the receptor upon TNF stimulation. IKK-ï§ï (NEMO), the regulatory subunit of the IKK complex, specifically recognizes these Lys63-linked polyubiquitins attached to RIP1 and thereby activates IKK and NF-kappaB (4, 5). A20 is an ubiquitin-modifying enzyme that inhibits NF-kappaB activation in succession of tumor necrosis factor (TNF) receptor and Toll-like receptor induced signals (6-8). This enzyme removes Lys63 linked ubiquitin chains from RIP1 and adds Lys48 polyubiquitins to RIP1, thereby targeting this factor for proteasomal degradation, thus explaining the molecular mechanism of NF-kappaB inhibition by A20 (6). A20 likely inhibits NF-kappaB acitivity also by additional means, including interaction with TRAF1 and TRAF2 (9). SNP 6.0 array (Affymetrix) analyses were performed according to the manufacturer's directions on DNA extracted from three Hodgkin cell lines (L1236, HDLM-2, U-HO1), HapMap samples included in the Genotyping Console Software 3.0 were used as references.
Project description:The bacterial product lipopolysaccharide (LPS) stimulates nuclear factor kB (NF-kB) signaling, which results in the production of proinflammatory cytokines, such as tumor necrosis factor-alpha (TNF-alpha), as part of the immune response. NF-kB target genes also include those encoding proteins that inhibit NF-kB signaling through negative feedback loops. By simultaneously studying the dynamics of the nuclear translocation of the NF-kB subunit RelA and the activity of a Tnf-driven reporter in a mouse macrophage cell line, Sung et al. found that the gene encoding RelA was also a target of NF-kB. Synthesis of RelA occurred only at higher concentrations of LPS and constituted a positive feedback loop that dominated over existing negative feedback mechanisms. Genes expressed in response to a high concentration of LPS were enriched for those involved in innate immune responses. Together, these data suggest that the RelA-dependent positive feedback loop enables macrophages to mount an effective immune only above a critical concentration of LPS.