The innate immune system is critical for clearing infection, and is tightly regulated to avert excessive tissue damage. Nod1/2-Rip2 signaling, which is essential for initiating the innate immune response to bacterial infection and ER stress, is subject to many regulatory mechanisms. In this study, we found that LRRK2, encoded by a gene implicated in Crohn's disease, leprosy and familial Parkinson's disease, modulates the strength of Nod1/2-Rip2 signaling by enhancing Rip2 phosphorylation. LRRK2 deficiency markedly reduces cytokine production in macrophages upon Nod2 activation by muramyl dipeptide (MDP), Nod1 activation by D-gamma-Glu-meso-diaminopimelic acid (iE-DAP) or ER stress. Our biochemical study shows that the presence of LRRK2 is necessary for optimal phosphorylation of Rip2 upon Nod2 activation. Therefore, this study reveals that LRRK2 is a new positive regulator of Rip2 and promotes inflammatory cytokine induction through the Nod1/2-Rip2 pathway.
Animals ; Cytokines ; genetics ; immunology ; HEK293 Cells ; Humans ; Immunity, Innate ; genetics ; Inflammation ; genetics ; immunology ; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2 ; genetics ; immunology ; Mice ; Mice, Knockout ; Nod1 Signaling Adaptor Protein ; genetics ; immunology ; Nod2 Signaling Adaptor Protein ; genetics ; immunology ; Phosphorylation ; genetics ; immunology ; Receptor-Interacting Protein Serine-Threonine Kinase 2 ; genetics ; immunology ; Receptor-Interacting Protein Serine-Threonine Kinases ; genetics ; immunology ; Signal Transduction ; genetics ; immunology

The innate immune response against viral infection is mainly relies on type I interferon, the production of which is mediated by TANK-binding kinase 1 (TBK1). It is revealed that the downstream TBK1 is activated by viral nucleic acid sensors RIG-I, cGAS and TLR3. The activity of TBK1 is complexly and precisely regulated by different type of protein modifications, including phosphorylation, ubiquitination and Sumolylation. This article focuses on the role of TBK1 in anti-viral innate immunity and the regulatory mechanism for the TBK1 activation.
Humans ; Immunity, Innate ; genetics ; physiology ; Interferon Type I ; Phosphorylation ; Protein Processing, Post-Translational ; immunology ; Protein-Serine-Threonine Kinases ; chemistry ; physiology ; Signal Transduction ; Ubiquitination ; Virus Diseases ; physiopathology

The host takes use of pattern recognition receptors (PRRs) to defend against pathogen invasion or cellular damage. Among microorganism-associated molecular patterns detected by host PRRs, nucleic acids derived from bacteria or viruses are tightly supervised, providing a fundamental mechanism of host defense. Pathogenic DNAs are supposed to be detected by DNA sensors that induce the activation of NFκB or TBK1-IRF3 pathway. DNA sensor cGAS is widely expressed in innate immune cells and is a key sensor of invading DNAs in several cell types. cGAS binds to DNA, followed by a conformational change that allows the synthesis of cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) from adenosine triphosphate and guanosine triphosphate. cGAMP is a strong activator of STING that can activate IRF3 and subsequent type I interferon production. Here we describe recent progresses in DNA sensors especially cGAS in the innate immune responses against pathogenic DNAs.
DNA, Bacterial ; immunology ; metabolism ; DNA, Viral ; immunology ; metabolism ; Gene Expression Regulation ; Host-Pathogen Interactions ; Humans ; Immunity, Innate ; Interferon Regulatory Factor-3 ; genetics ; immunology ; Interferon Type I ; biosynthesis ; immunology ; Membrane Proteins ; genetics ; immunology ; Models, Molecular ; NF-kappa B ; genetics ; immunology ; Nucleotides, Cyclic ; biosynthesis ; immunology ; Nucleotidyltransferases ; genetics ; immunology ; Protein Binding ; Protein-Serine-Threonine Kinases ; genetics ; immunology ; Signal Transduction

OBJECTIVETo investigate the inhibiting action of transforming growth factor-beta type R II receptor(TGF-beta R II) antibody to fibroblasts.

METHODSFour groups of cultured skin fibroblasts were treated with different dosages of TGF-beta R II antibody. Examinations were performed with HYP, MTT, microscope, and flow cytometry techniques.

RESULTSTGF-beta R II antibody resulted in significant inhibition of fibroblasts(P < 0.01).

CONCLUSIONTGF-beta R II antibody has inhibiting effects on the proliferation of skin fibroblasts and with a dose-dependent manner.

Adolescent ; Antibodies, Monoclonal ; pharmacology ; Cell Division ; drug effects ; Cells, Cultured ; Child ; Fibroblasts ; cytology ; drug effects ; ultrastructure ; Flow Cytometry ; Humans ; Microscopy, Electron ; Protein-Serine-Threonine Kinases ; Receptors, Transforming Growth Factor beta ; analysis ; immunology

OBJECTIVE: To analyze the effects of mangiferin combined with bortezomib on the proliferation, invasion, apoptosis and autophagy of human Burkitt lymphoma Raji cells, as well as the expression of CXC chemokine receptors (CXCRs) family, and explore the molecular mechanism between them to provide scientific basis for basic research and clinical work of Burkitt lymphoma. METHODS: Raji cells were intervened with different concentrations of mangiferin and bortezomib alone or in combination, then cell proliferation was detected by CCK-8 assay, cell invasion ability was detected by Transwell chamber method, cell apoptosis was detected by Annexin V/PI double-staining flow cytometry, apoptosis, autophagy and Akt/mTOR pathway protein expression were detected by Western blot, and the expression changes of CXCR family was detected by real-time quantitative PCR (RT-qPCR). RESULTS: Different concentrations of mangiferin intervened Raji cells for different time could inhibit cell viability in a concentration- and time-dependent manner (r =-0.682, r =-0.836). When Raji cells were intervened by combination of mangiferin and bortezomib, compared with single drug group, the proliferation and invasion abilities were significantly decreased, while the apoptosis level was significantly increased (P <0.01). Mangiferin combined with bortezomib could significantly up-regulate the expression of pro-apoptotic protein Bax and down-regulate the expression of anti-apoptotic protein Bcl-2 after intervention in Raji cells. Caspase-3 was also hydrolyzed and activated, and then induced the apoptosis of Raji cells. Mangiferin combined with bortezomib could up-regulate the expression of LC3Ⅱ protein in Raji cells, and the ratio of LC3Ⅱ/LC3Ⅰ in cells was significantly up-regulated compared with single drug or control group (P <0.01). Mangiferin combined with bortezomib could significantly inhibit the phosphorylation levels of Akt and mTOR, inhibit the proliferation and invasion of Raji cells by inhibiting Akt/mTOR pathway, and induce cell autophagy and apoptosis. Mangiferin and bortezomib could down-regulate the expressions of CXCR4 and CXCR7 mRNA after single-agent intervention in Raji cells, and the down-regulations of CXCR4 and CXCR7 mRNA expression were more significant when the two drugs were combined (P <0.01). Mangiferin alone or combined with bortezomib had no significant effect on CXCR5 mRNA expression in Raji cells (P >0.05), while the combination of the two drugs could down-regulate the expression of CXCR3 (P <0.05). CONCLUSION Mangiferin combined with bortezomib can synergistically inhibit the proliferation and invasion of Raji cells, and induce autophagy and apoptosis. The mechanism may be related to the inhibition of Akt/mTOR signaling pathway, down-regulation of anti-apoptotic protein Bcl-2 and up-regulation of pro-apoptotic protein Bax, and the inhibition of the expression of CXCR family.
Humans ; Antineoplastic Agents/therapeutic use* ; Apoptosis/drug effects* ; Apoptosis Regulatory Proteins/immunology* ; Autophagy/immunology* ; bcl-2-Associated X Protein/immunology* ; Bortezomib/therapeutic use* ; Burkitt Lymphoma/immunology* ; Cell Line, Tumor ; Cell Proliferation/drug effects* ; Drug Therapy, Combination ; Proto-Oncogene Proteins c-akt ; Proto-Oncogene Proteins c-bcl-2 ; Receptors, CXCR/immunology* ; RNA, Messenger ; TOR Serine-Threonine Kinases ; Xanthones/therapeutic use*

Tumor associated microtubule associated protein (TMAP), also known as cytoskeleton associated protein 2 (CKAP2) is a mitotic spindle-associated protein whose expression is cell cycle-regulated and also frequently deregulated in cancer cells. Two monoclonal antibodies (mAbs) against TMAP/CKAP2 were produced: B-1-13 and D-12-3. Interestingly, the reactivity of mAb D-12-3 to TMAP/CKAP2 was markedly decreased specifically in mitotic cell lysate. The epitope mapping study showed that mAb D-12-3 recognizes the amino acid sequence between 569 and 625 and that phosphorylation at T596 completely abolishes the reactivity of the antibody, suggesting that the differential reactivity originates from the phosphorylation status at T596. Immunofluorescence staining showed that mAb D-12-3 fails to detect TMAP/CKAP2 in mitotic cells between prophase and metaphase, but the staining becomes evident again in anaphase, suggesting that phosphorylation at T596 occurs transiently during early phases of mitosis. These results suggest that the cellular functions of TMAP/CKAP2 might be regulated by timely phosphorylation and dephosphorylation during the course of mitosis.
Amino Acid Sequence ; Animals ; Antibodies, Monoclonal/metabolism/pharmacology ; Cell Cycle/physiology ; Cells, Cultured ; Cytoskeletal Proteins/chemistry/immunology/*metabolism/physiology ; Epitope Mapping ; Hela Cells ; Humans ; Mice ; Mitosis/*physiology ; Molecular Sequence Data ; Phosphorylation ; Protein-Serine-Threonine Kinases/*metabolism ; Sequence Homology, Amino Acid ; Threonine/metabolism

Pentraxin 3 (PTX3) was identified as a marker of the inflammatory response and overexpressed in various tissues and cells related to cardiovascular disease. Honokiol, an active component isolated from the Chinese medicinal herb Magnolia officinalis, was shown to have a variety of pharmacological activities. In the present study, we aimed to investigate the effects of honokiol on palmitic acid (PA)-induced dysfunction of human umbilical vein endothelial cells (HUVECs) and to elucidate potential regulatory mechanisms in this atherosclerotic cell model. Our results showed that PA significantly accelerated the expression of PTX3 in HUVECs through the IkappaB kinase (IKK)/IkappaB/nuclear factor-kappaB (NF-kappaB) pathway, reduced cell viability, induced cell apoptosis and triggered the inflammatory response. Knockdown of PTX3 supported cell growth and prevented apoptosis by blocking PA-inducted nitric oxide (NO) overproduction. Honokiol significantly suppressed the overexpression of PTX3 in PA-inducted HUVECs by inhibiting IkappaB phosphorylation and the expression of two NF-kappaB subunits (p50 and p65) in the IKK/IkappaB/NF-kappaB signaling pathway. Furthermore, honokiol reduced endothelial cell injury and apoptosis by regulating the expression of inducible NO synthase and endothelial NO synthase, as well as the generation of NO. Honokiol showed an anti-inflammatory effect in PA-inducted HUVECs by significantly inhibiting the generation of interleukin-6 (IL-6), IL-8 and monocyte chemoattractant protein-1. In summary, honokiol repaired endothelial dysfunction by suppressing PTX3 overexpression in an atherosclerotic cell model. PTX3 may be a potential therapeutic target for atherosclerosis.
Apoptosis/drug effects ; Atherosclerosis/chemically induced/*drug therapy/immunology/pathology ; Biphenyl Compounds/chemistry/isolation & purification/*pharmacology ; C-Reactive Protein/*genetics/immunology ; Down-Regulation/drug effects ; Drugs, Chinese Herbal/chemistry/isolation & purification/*pharmacology ; Human Umbilical Vein Endothelial Cells ; Humans ; I-kappa B Kinase/*immunology ; Lignans/chemistry/isolation & purification/*pharmacology ; Magnolia/chemistry ; Palmitic Acid ; Protein-Serine-Threonine Kinases/*immunology ; Serum Amyloid P-Component/*genetics/immunology ; Signal Transduction/drug effects

Tumor hypoxia contributes to the progression of a malignant phenotype and resistance to ionizing radiation and anticancer drug therapy. Many of these effects in hypoxic tumor cells are mediated by expression of specific set of genes whose relation to therapy resistance is poorly understood. In this study, we revealed that DNA-dependent protein kinase (DNA-PK), which plays a crucial role in DNA double strand break repair, would be involved in regulation of hypoxia inducible factor-1 (HIF-1). HIF-1beta-deficient cells showed constitutively reduced expression and DNA-binding activity of Ku, the regulatory subunit of DNA-PK. Under hypoxic condition, the expression and activity of DNA- PK were markedly induced with a concurrent increase in HIF-1alpha expression. Our result also demonstrated that DNA-PK could directly interact with HIF- and especially DNA-PKcs, the catalytic subunit of DNA-PK, could be involved in phosphorylation of HIF-1alpha, suggesting the possibility that the enhanced expression of DNA- PK under hypoxic condition might attribute to modulate HIF-1alpha stabilization. Thus, the correlated regulation of DNA-PK with HIF-1 could contribute to therapy resistance in hypoxic tumor cells, and it provides new evidence for developing therapeutic strategies enhancing the efficacy of cancer therapy in hypoxic tumor cells.
Antibodies/immunology ; Cell Hypoxia ; Cell Line, Tumor ; DNA Helicases/immunology/metabolism ; DNA-Binding Proteins/genetics/*metabolism/*physiology ; Deferoxamine/pharmacology ; Drug Resistance, Neoplasm/*physiology ; Humans ; Immunoprecipitation ; Neoplasms/enzymology/*metabolism ; Nuclear Proteins/genetics/*metabolism/physiology ; Phosphorylation ; Protein-Serine-Threonine Kinases/metabolism/*physiology ; Research Support, Non-U.S. Gov't ; Transcription Factors/genetics/*metabolism/physiology ; Up-Regulation

OBJECTIVETo explore the activation status of signal pathway of mTOR/S6 in bone marrow (BM) T lymphocytes of refractory/relapsed aplastic anemia patients (AA), and the effects of rapamycin (RAPA) and CTLA-4 immunoglobulin (CTLA-4Ig) on this pathway.

METHODSBM was collected from 13 refractory/relapsed AA patients, 8 newly diagnosed severe AA (SAA) patients and 10 iron deficiency anemia (IDA) (as controls) patients, and cocultured with RAPA and CTLA-4 Ig. The expression of p-mTOR, p-S6 and Interferon gamma (IFN-gamma) in CD3(+)T cells was measured by flow cytometry (FCM).

RESULTS(1) The expression of p-mTOR, p-S6 and IFN-gamma in CD3(+)T cells in refractory/relapsed AA group were significantly higher than those in controls (P < 0.01). (2) The expression of p-mTOR and p-S6 in T cells in newly diagnosed SAA group, was similar to those in controls (P > 0.05), but significantly lower than those in refractory/relapsed AA group (P < 0.01). The expression level of IFN-gamma in T cells were significantly higher than that in controls (P < 0.01). (3) On exposure to RAPA, the levels of p-mTOR, p-S6 and IFN-gamma in T cells in refractory/relapsed AA patients were significantly lower than those before the exposure (all P < 0.05). And so were when exposed to CTLA-4 Ig (all P < 0.01).

CONCLUSION(1) The mTOR/S6 signal pathway is activated in refractory/relapsed AA. (2) The expression of p-mTOR, p-S6 and IFN-gamma in refractory/relapsed AA can be suppressed by RAPA or CTLA-4Ig. (3) The signal pathway of CD28/mTOR/S6/IFN-gamma might take part in immune pathogenesis of refractory/relapsed AA.

Adolescent ; Adult ; Aged ; Anemia, Aplastic ; immunology ; metabolism ; Antigens, CD ; pharmacology ; CTLA-4 Antigen ; Child ; Female ; Humans ; Interferon-gamma ; metabolism ; Male ; Middle Aged ; Ribosomal Protein S6 ; metabolism ; Signal Transduction ; drug effects ; Sirolimus ; pharmacology ; T-Lymphocytes ; immunology ; metabolism ; TOR Serine-Threonine Kinases ; metabolism ; Young Adult

A previous report by this laboratory demonstrated that bacterial iron chelator (siderophore) triggers inflammatory signals, including the production of CXC chemokine IL-8, in human intestinal epithelial cells (IECs). Microarray-based gene expression profiling revealed that iron chelator also induces macrophage inflammatory protein 3 alpha (MIP-3alpha)/ CC chemokine-ligand 20 (CCL20). As CCL20 is chemotactic for the cells involved in host adaptive immunity, this suggests that iron chelator may stimulate IECs to have the capacity to link mucosal innate and adaptive immunity. The basal medium from iron chelator deferoxamine (DFO)-treated HT-29 monolayers was as chemotactic as recombinant human CCL20 at equivalent concentrations to attract CCR6+ cells. The increase of CCL20 protein secretion appeared to correspond to that of CCL20 mRNA levels, as determined by real-time quantitative RT-PCR. The efficacy of DFO at inducing CCL20 mRNA was also observed in human PBMCs and in THP-1 cells, but not in human umbilical vein endothelial cells. Interestingly, unlike other proinflammatory cytokines, such as TNF-alpha and IL-1beta, a time-dependent experiment revealed that DFO slowly induces CCL20, suggesting a novel mechanism of action. A pharmacologic study also revealed that multiple signaling pathways are differentially involved in CCL20 production by DFO, while some of those pathways are not involved in TNF-alpha-induced CCL20 production. Collectively, these results demonstrate that, in addition to some bacterial products known to induce host adaptive immune responses, direct chelation of host iron by infected bacteria may also contribute to the initiation of host adaptive immunity in the intestinal mucosa.
Calcium/metabolism ; Cell Movement/drug effects ; Chemokines, CC/genetics/*metabolism ; Deferoxamine/*pharmacology ; Egtazic Acid/analogs & derivatives/pharmacology ; HT29 Cells ; Humans ; Immunity, Mucosal/*drug effects ; Intestinal Mucosa/*drug effects/immunology/metabolism ; Iron Chelating Agents/*pharmacology ; Macrophage Inflammatory Proteins/genetics/*metabolism ; NF-kappa B/metabolism ; Phosphoprotein Phosphatase/physiology ; Protein Transport/drug effects ; Protein-Serine-Threonine Kinases/physiology ; RNA, Messenger/genetics/metabolism ; Receptors, Chemokine/metabolism ; Research Support, Non-U.S. Gov't