[Show abstract][Hide abstract] ABSTRACT: Interleukin-32 (IL-32) is a cytokine and inducer of various proinflammatory cytokines such as TNFα, IL-1β, and IL-6 as well as chemokines. There are five splicing variants (α, β, γ, delta, and epsilon) and IL-32γ is the most active isoform. We generated human IL-32γ transgenic (IL-32γ TG) mice to express high level of IL-32γ in various tissues including immune cells. The pathology of sepsis is based on systemic inflammatory response that is characterized by upregulating inflammatory cytokines in whole body, particularly in response to Gram negative bacteria. We investigated the role of IL-32γ in a mouse model of experimental sepsis by using lipopolysaccharides (LPS). We found that IL-32γTG mice resist LPS-induced lethal endotoxemia. IL-32γ reduced systemic cytokines release after LPS administration but not the local immune response. IL-32γTG increased neutrophil influx into the initial foci of the primary injected site and prolonged local cytokines and chemokines production. These results suggest that neutrophil recruitment in IL-32γTG occurred as a result of the local induction of chemokines but not the systemic inflammatory cytokine circulation. Together, our results suggest that IL-32γ enhances an innate immune response against local infection but inhibits the spread of immune responses leading to systemic immune disorder.
Journal of Microbiology and Biotechnology 04/2014; · 1.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Interleukin-32 (IL-32) is a cytokine produced by T lymphocytes, natural killer (NK) cells, monocytes and epithelial cells. There are five splicing variants (α, β, γ, δ, and ε) and IL-32γ is the most active isoform. We generated human IL-32γ transgenic (IL-32γ TG) mice, displaying a high level of IL-32γ expression in the pancreas. We investigated the effect of IL-32γ on streptozotocin (STZ)-induced type 1 diabetes model using IL-32γ TG mice. After a suboptimal diabetogenic dose of STZ administration, IL-32γ TG mice showed significantly increased blood glucose level comparing with that of wild type (WT) mice at day 5. Inflammatory cytokines levels such as, IL-6, TNFα, IFNγ and IL-1β, in pancreas and liver lysates were accessed by a specific cytokine ELISA. The proinflammatory cytokines were significantly enhanced in the pancreas of IL-32γ TG mice comparing to that of WT mice whereas those cytokines levels in liver of IL-32γ TG and WT mice were not changed by STZ. These data indicate that the overexpression of IL-32γ contributes to initial islet β-cells injury and inflammation in pancreas and aggravates STZ-induced type 1 diabetes.
[Show abstract][Hide abstract] ABSTRACT: Avascular necrosis of the femoral head (ANFH) is commonly observed in patients treated with excessive glucocorticoid (GC). Single administration of lipopolysaccharide (LPS) has shown to induce immune stimulatory factors. However, the effect of repeated administration of LPS on GC-induced ANFH has not been studied. Thus the purpose of this study was (i) to examine cytokine profile-induced by repeated LPS administrations and (ii) to test the effect of repeated LPS treatments on GC-induced ANFH. A mouse necrosis model of ANFH was designed by chronic GC administration with co-treatment of LPS. Mice body weights in the LPS/prednisolone (PDN) co-treated group were lower than that of the untreated control group, but spleen weights were great than the control group. The levels of IL-6, TNFα and IL-33 in the liver and spleen of LPS/PDN group were lower than the untreated control group whereas TNFα level in the femoral head of the LPS/PDN group increased. Collectively, The effect of repeated LPS on pathogenesis of the GC-induced ANFH was associated with TNFα level in the femoral head but the pathogenesis was not correspond to cytokine levels in immune tissues.
Journal of Microbiology and Biotechnology 12/2013; · 1.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The pro-inflammatory cytokines tumor necrosis factor-α (TNFα) and interleukin (IL)-1β are crucial mediators involved in chronic inflammatory diseases. Inflammatory signal pathways regulate inflammatory cytokine expression-mediated by p38 mitogen activated protein kinase (p38MAPK). Therefore, considerable attention has been given to p38MAPK as a target molecule for the development of a novel anti-inflammatory therapeutics. BIRB 796, one of p38MAPK inhibitor, is a candidate of therapeutic drug for chronic inflammatory diseases. In this study, we investigated the effect of BIRB 796 on inflammatory cytokine productions by lipopolysaccharide (LPS) in different immune cell types. BIRB 796 reduced LPS-mediated IL-8 production in THP-1 cells but not in Raw 264.7 cells. Further analysis of signal molecules by western blot revealed that BIRB 796 sufficiently suppressed LPS-mediated phosphorylation of p38MAPK in both cell types whereas it failed to block inhibitor of kappa B (I-κB) degradation in Raw 264.7 cells. Taken together, these results suggest that the anti-inflammatory function of BIRB 796 depends on cell types.
[Show abstract][Hide abstract] ABSTRACT: Among the 11 members of the IL-1 family cytokines, the precursors of IL-1α, IL-1β, and IL-33 have relatively long N-terminal pro-sequences of approximately 100 amino acid residues prior to the N-terminus of the mature forms. Compared to the mature forms secreted from the cell, 80-90% of the primary translation product is in the intracellular compartment in the precursor form. However, the precursors are readily released from cells during infections but also with non-infectious conditions such a hypoxia and trauma. In this setting, the precursors act rapidly as "alarmins" in the absence of a processing mechanism to remove the pro-sequence and generate a mature form. In the case of IL-1α, the release of the precursor activates adjacent cells via receptor-mediated signaling. However, there are no data comparing the specific activity of the IL-1α precursor to the mature form. In the present study, we compared the precursor and mature forms of recombinant human IL-1α, IL-1β, and IL-33 proteins on the induction of cytokines from A549 cells as well as from human peripheral blood mononuclear cells (PBMC). Similar to the mature form, the IL-1α precursor was active in inducing IL-6 and TNFα, whereas the precursor forms of IL-1β and IL-33 were not active. On PBMC, precursor and mature IL-1α at 0.04 and 0.2 nM were equally active in inducing IL-6. Given the fact that during necrotic cell death, the IL-1α precursor is released intact and triggers IL-1 receptors on tissue macrophages, these data identify the precursor form of IL-1α as a key player in sterile inflammation.
[Show abstract][Hide abstract] ABSTRACT: Interferons (IFNs) are commonly grouped into type I and type II IFN. Type I IFNs are known as antiviral IFNs including IFN-α, IFN-β, and IFN-ω whereas type II IFN is referred to immune IFN and IFN-γ is only member of the type II IFN. Type I IFNs are induced by virus invading however type II IFN is produced by mitogenic or antigenic stimuli. IFN-τ was first identified in ruminant ungulates as a pregnancy recognition hormone, trophoblastin. IFN-τ constitutes a new class of type I IFN, which possesses the common features of type I IFN, such as the ability to prevent viral infection and to limit cell proliferation. In addition, IFN-τ is unique in that it is induced by pregnancy unlike other type I IFNs. We cloned Bos taurus (B. T.) Coreanae IFN-τ from peripheral blood mononuclear cells. The amino acid sequence of B. T. Coreanae IFN-τ shares only 90.3% identity with that of Holstein dairy cow. Recombinant B. T. Coreanae and Holstein IFN-τ proteins were expressed in Escherichia coli and the antiviral activity of IFN-τ proteins were examined. Both recombinant proteins were active and protected human WISH and bovine MDBK cells from the cytopathic effect of vesicular stomatitis virus. The recombinant IFN-τ protein of B. T. Coreanae and Holstein properly induced the expression of antiviral genes including 2',5'-oligoadenylate synthetase (OAS) and Mx GTPase 1 (Mx-1).
[Show abstract][Hide abstract] ABSTRACT: Cytokines are essential coordinators of defensive immune responses for resolving the invasion of pathogens such as bacteria, virus, and fungi. However, dysregulated cytokines are the main cause of various autoinflammatory immune disorders such as rheumatoid arthritis, inflammatory bowel disease, and psoriasis. Interleukin-32 (IL-32) is a recently described cytokine and characterized as a proinflammatory cytokine. IL-32 stimulates monocytes and macrophages to induce important proinflammatory cytokines (IL-1β, IL-6, and TNFα) and chemokines (IL-8 and MIP-2) by activating the NF-κB and p38 mitogen-activated protein (MAP) kinase pathways. The biological activities of IL-32 are associated with epidemic pathogens, Mycobacterium tuberculosis, influenza A virus, and human immunodeficiency virus (HIV). IL-32 is transcribed as six alternative splice variants (α, β, γ, δ, ɛ, and ζ), with IL-32γ being the most active isoform. However, it is unclear which isoform is related to specific disease activities since there are no high quality antibodies available to measure circulating IL-32 in biological samples of patients. Therefore, we developed specific anti-human IL-32γ monoclonal antibodies from recombinant human IL-32γ, which was expressed in Escherichia coli. The IL-32γ specific monoclonal antibodies recognized IL-32 in cell culture supernatants and serum of IL-32γ transgenic mice. The newly developed IL-32γ monoclonal antibodies will be a useful tool to measure IL-32 level in serum samples of various inflammatory diseases. These monoclonal antibodies will be helpful in investigating the precise function of IL-32 in immune responses and in autoinflammatory diseases.
[Show abstract][Hide abstract] ABSTRACT: Interleukin-18 binding protein (IL-18BP) is a soluble antagonist of IL-18 originally discovered while attempting to isolate a soluble receptor by using IL-18-ligand affinity column. IL-18BP has four isoforms (a, b, c, and d) in humans and two isoforms (c and d) in mice. The human isoforms IL-18BPa and IL-18BPc neutralize IL-18 activity sufficiently at an equimolar ratio; however IL-18BPb and IL-18BPd isoforms lack a complete Ig domain at C-terminus and lose the ability to neutralize IL-18 activity. Mouse IL-18BPc and IL-18BPd isoforms, possessing a similar complete Ig domain, also neutralize the biological activity of mouse IL-18 at an equimolar ratio. Here we expressed recombinant proteins of the active human IL-18BP isoforms and developed monoclonal antibodies (MAbs) against human IL-18BP a and c isoforms. We obtained two MAbs (78-4 and 38-3) of human IL-18BPa and two MAbs (18-7 and 29-6) of human IL-18BPc. The MAb clones 18-7 and 29-6 specifically recognized recombinant IL-18BPc in Western blot analyses and ELISA, whereas the MAb clone 78-4 recognized both isoforms in Western blot analyses, but only human IL-18BPa isoform in ELISA. We developed a sandwich ELISA by using the monoclonal antibody specific to human IL-18BPa isoform. The isoform-specific anti-human IL-18BP MAb may be a useful tool in categorizing a distinct group of patients from various autoimmune diseases related to IL-18BP.
[Show abstract][Hide abstract] ABSTRACT: Inflammatory cytokines mediate inflammatory bowel diseases (IBDs) and cytokine blocking therapies often ameliorate the disease severity. IL-32 affects inflammation by increasing the production of IL-1, TNFα, and several chemokines. Here, we investigated the role of IL-32 in intestinal inflammation by generating a transgenic (TG) mouse expressing human IL-32γ (IL-32γ TG). Although IL-32γ TG mice are healthy, constitutive serum and colonic tissue levels of TNFα are elevated. Compared with wild-type (WT) mice, IL-32γ TG mice exhibited a modestly exacerbated acute inflammation early following the initiation of dextran sodium sulfate (DSS)-induced colitis. However, after 6 d, there was less colonic inflammation, reduced tissue loss, and improved survival rate compared with WT mice. Associated with attenuated tissue damage, colonic levels of TNFα and IL-6 were significantly reduced in the IL-32γ TG mice whereas IL-10 was elevated. Cultured colon explants from IL-32γ TG mice secreted higher levels of IL-10 compared with WT mice and lower levels of TNFα and IL-6. Constitutive levels of IL-32γ itself in colonic tissues were significantly lower following DSS colitis. Although the highest level of serum IL-32γ occurred on day 3 of colitis, IL-32 was below constitutive levels on day 9. The ability of IL-32γ to increase constitutive IL-10 likely reduces TNFα, IL-6, and IL-32 itself accounting for less inflammation. In humans with ulcerative colitis (UC), serum IL-32 is elevated and colonic biopsies contain IL-32 in inflamed tissues but not in uninvolved tissues. Thus IL-32γ emerges as an example of how innate inflammation worsens as well as protects intestinal integrity.
Proceedings of the National Academy of Sciences 11/2010; 107(49):21082-6. · 9.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Post-translational modifications of target proteins by small ubiquitin-like modifier (SUMO) proteins modulate many cellular processes in yeast and animals. Here we present the development of monoclonal antibodies (MAb) and polyclonal antibodies (PAb) against Arabidopsis SIZ1 (AtSIZ1) protein with high specificity. Mice were immunized with recombinant AtSIZ1 protein for generating monoclonal antibodies via the classic hybridoma production technique. Anti-AtSIZ1 MAb and PAb were able to detect endogenous AtSIZ1 in Arabidopsis wild type and its complementary line formed by transforming C-siz1-2 mutant with construct containing the AtSIZ1 gene under the control of the native promoter, but not the siz1-2 deletion mutant. These results show that these anti-AtSIZ MAbs are highly sensitive to detect endogenous AtSIZ1 and can be used for immunoblotting and other experimental methods. The new anti-AtSIZ1 MAbs will be essential tools used to investigate the role of AtSIZ1 in plant developmental biology.