Objective To investigate the expressions of IL-18, IL-18 binding protein isoform a (IL-18BPa) and IL-18 receptor α (IL-18Rα) in blood CD4⁺ Th2 cells of patients with allergic rhinitis (AR) and the effects of allergens on their expressions. Methods Blood samples of AR patients and healthy control subjects (HCs) were collected. Peripheral blood mononuclear cells (PBMCs) and CD4⁺ T cells sorted by immunomagnetic beads were stimulated by crude extract of Artemisia sieversiana wild allergen (ASWE), Platanus pollen (PPE) and house dust mite extract (HDME). Flow cytometry was used to detect the expression of IL-18, IL-18BPa and IL-18Rα in CD4⁺ Th2 cells, and BioPlex was used to detect the level of plasma IL-4 and analyze its correlation with the proportion of IL-18⁺ Th2 cells. Results Compared with HCs, the proportion of IL-18⁺ cells was increased in Th2 cells of AR patients; MFI of IL-18 was increased, while that of IL-18Rα was decreased. Moreover, allergens induced IL-18 and IL-18Rα expression in sorted CD4⁺ Th2 cells of HCs and induced IL-18Rα in that of AR patients. Additionally, elevated plasma IL-4 level was found in AR patients, which was moderately correlated with the percentage of IL-18⁺ Th2 cells. Conclusion Allergens may be involved in the pathogenesis of AR by inducing expression of IL-18 in peripheral blood CD4⁺ Th2 cells.
Humans ; Th2 Cells ; Interleukin-18/metabolism* ; Up-Regulation ; Leukocytes, Mononuclear/metabolism* ; Interleukin-4/metabolism* ; Rhinitis, Allergic/metabolism* ; Allergens ; Cytokines/metabolism*

OBJECTIVETo determine the concentrations of interleukin-18 (IL-18), IL-6, IL-8, and prostaglandin E2 (PGE2) in the synovial fluid in patients with osteoarthritis (OA), and explore the role of IL-18 in the pathogenesis of OA.

METHODSThe synovial fluid was collected from 30 patients with knee OA, and the concentrations of IL-18 and the other cytokines were measured using enzyme-linked immunosorbent assay (ELISA). A linear regression was performed between IL-18 and the other cytokines.

RESULTSThe average IL-18 and PGE2 concentrations were 220-/+304 pg/ml and 89-/+104 pg/ml in the synovial fluid, respectively, and the two cytokines showed a positive correlation in the synovial fluid (r=0.628, P=0.001). The IL-18 concentration was also correlated to the concentrations of IL-6 (1200-/+1587 pg/ml, n=22; r=0.590, P=0.008) and IL-8 (5190-/+6024 pg/ml, n=9; r=0.776, P=0.014).

CONCLUSIONIL-18 can promote PGE2 production, which causes cartilage degradation in OA, thus therapies targeting this cytokine may prove an effective approach to early OA treatment.

Aged ; Dinoprostone ; biosynthesis ; Female ; Humans ; Interleukin-18 ; metabolism ; Male ; Middle Aged ; Osteoarthritis ; metabolism ; Synovial Fluid ; metabolism

Adult ; Ascitic Fluid ; metabolism ; Endometriosis ; blood ; metabolism ; Female ; Humans ; Interleukin-18 ; analysis ; blood ; Middle Aged

Inflammatory bowel disease (IBD), the most important entities being ulcerative colitis and Crohn's disease, are chronic, relapsing and remitting inflammatory conditions that result from chronic dysregulation of the mucosal immune system in the intestinal tract. Although the precise pathogenesis of IBD is still incompletely understood, increased levels of proinflammatory cytokines, including interleukin (IL)-1beta, IL-18 and tumor necrosis factor-alpha, are detected in active IBD and correlate with the severity of inflammation, indicating that these cytokines may play a key role in the development of IBD. Recently, the intracellular nucleotide-binding oligomerization domain-like receptor (NLR) family members, including NLRP1, NLRP3, NLRC4 and NLRP6, are emerging as important regulators of intestinal homeostasis. Together, one of those aforementioned molecules or the DNA sensor absent in melanoma 2 (AIM2), apoptosis-associated speck-like protein containing 'a caspase recruitment domain (CARD)' (ASC) and caspase-1 form a large (>700 kDa) multi-protein complex called the inflammasome. Stimulation with specific microbial and endogenous molecules triggers inflammasome assembly and caspase-1 activation. Activated caspase-1 leads to the secretion of proinflammatory cytokines, including IL-1beta and IL-18, and the promotion of pyroptosis, a form of phagocyte cell death induced by bacterial pathogens, in an inflamed tissue. Therefore, inflammasomes are assumed to mediate host defense against microbial pathogens and gut homeostasis, so that their dysregulation might contribute to IBD pathogenesis. This review focuses on recent advances of the role of NLRP3 inflammasome signaling in IBD pathogenesis. Improving knowledge of the inflammasome could provide insights into potential therapeutic targets for patients with IBD.
CARD Signaling Adaptor Proteins/metabolism ; Carrier Proteins/metabolism/physiology ; Caspase 1/metabolism ; Humans ; Inflammasomes/*metabolism ; Inflammatory Bowel Diseases/metabolism/*pathology ; Interleukin-18/metabolism ; Interleukin-1beta/metabolism ; Signal Transduction

Humans ; Interleukin-18 ; chemistry ; metabolism ; Pulmonary Fibrosis ; etiology ; pathology ; Silicosis ; complications ; pathology ; physiopathology

OBJECTIVE: To detect the concentrations of interleukin-18 (IL-18) and prostaglandin E2(PGE2) in synovial fluid (SF), and to determine the role of IL-18 and PGE2 in osteoarthritis (OA) pathogenesis. METHODS: IL-18 and PGE2 were measured concurrently in synovial fluid samples from 54 patients with knee OA (OA group) and from 9 controls (control group). Quantitative determination of IL-18 was performed by enzyme-linked immunosorbent assay (ELISA). PGE2 was examined by inhibitory enzyme-linked immunosorbent assay. A linear regression between IL-18 and PGE2 was analysed. RESULTS: The concentrations of IL-18 and PGE2 in SF from the OA group were significantly higher than those from the control group (P<0.01). The average value of IL-18 in the control group was (28.768+/-13.575) x 10(-9)ng/L, and (72.303+/-40.130) x 10(-9)ng/L in the OA group (P<0.01); the average value of PGE2 in the control group was (24.697+/-7.814) x 10(-9)ng/L, and (42.302+/-23.818) x 10(-9)ng/L in the OA group (P<0.01). IL-18 was related with PGE2 in a linear curve fashion (the control group: r=0.76, P<0.001; the OA group: r=0.94, P<0.001). CONCLUSION IL-18 and PGE2 are significantly higher in the OA group than those in the control group, and they might take part in the cartilage degradation in OA pathogenesis. The increase of IL-18 might induce the increase of PGE2, and that might play an important role in OA pathogenesis.
Adult ; Aged ; Case-Control Studies ; Dinoprostone ; metabolism ; Female ; Humans ; Interleukin-18 ; metabolism ; Male ; Middle Aged ; Osteoarthritis ; metabolism ; Synovial Fluid ; metabolism

Objective: To investigate the role of Maresin1 (MaR1) in hepatic ischemia-reperfusion injury (HIRI). Methods: The HIRI model was established and randomly divided into a sham operation group (Sham group), an ischemia-reperfusion group (IR group), and a MaR1 ischemia-reperfusion group (MaR1+IR group). MaR1 80ng was intravenously injected into each mouse's tail veins 0.5h before anesthesia. The left and middle hepatic lobe arteries and portal veins were opened and clamped. The blood supply was restored after 1h of ischemia. After 6h of reperfusion, the mice were sacrificed to collect blood and liver tissue samples. The Sham's group abdominal wall was only opened and closed. RAW267.4 macrophages were administered with MaR1 50ng/ml 0.5h before hypoxia, followed by hypoxia for 8h and reoxygenation for 2h, and were divided into the control group, the hypoxia-reoxygenation group (HR group), the MaR1 hypoxia-reoxygenation group (MaR1 + HR group), the Z-DEVD-FMK hypoxia-reoxygenation group (HR+Z group), the MaR1 + Z-DEVD-FMK hypoxia-reoxygenation group (MaR1 + HR + Z group), and the Con group without any treatment. Cells and the supernatant above them were collected. One-way analysis of variance was used for inter-group comparisons, and the LSD-t test was used for pairwise comparisons. Results: Compared with the Sham group, the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), interleukin (IL)-1β, and IL-18 in the IR group were significantly higher (P < 0.05), with remarkable pathological changes, while the level in the MaR1 + IR group was lower than before (P < 0.05), and the pathological changes were alleviated. Compared with the Con group, the HR group had higher levels of IL-1β and IL-18 (P < 0.05), while the MaR1 + HR group had lower levels of IL-1β and IL-18 (P < 0.05). Western blot showed that the expressions of caspase-3, GSDME, and GSDME-N were significantly higher in the HR group and IR group than in the other groups; however, the expression was lower following MaR1 pretreatment. The Z-DEVD-FMK exploration mechanism was inhibited by the expression of caspase-3 in HIRI when using MaR1. Compared with the HR group, the IL-1β and IL-18 levels and the expressions of caspase-3, GSDME, and GSDME-N in the HR + Z group were decreased (P < 0.05), while the expression of nuclear factor κB was increased, but following MaR1 pretreatment, nuclear factor κB was decreased. There was no significant difference in the results between the MaR1 + H/R group and the MaR1 + H/R + Z group (P > 0.05). Conclusion: MaR1 alleviates HIRI by inhibiting NF-κB activation and caspase-3/GSDME-mediated inflammatory responses.
Mice ; Animals ; NF-kappa B/metabolism* ; Interleukin-18/metabolism* ; Caspase 3/metabolism* ; Liver/pathology* ; Signal Transduction ; Reperfusion Injury/metabolism*

BACKGROUND: As a potent pro-inflammatory cytokine of the interleukin (IL)-1 family, IL-18 was elevated in early active and progressive plaque-type psoriatic lesions and that serum or plasma levels of IL-18 correlated with the Psoriasis Area and Severity Index (PASI). Although results from previous studies have established that IL-18 may aggravate psoriatic inflammation, the mechanisms of this process remain unknown. In this study, IL-18 knock out (KO) mice and wild-type (WT) mice were used to investigate the effects of IL-18 within a mouse model of psoriasis. METHODS: WT and IL-18 KO mice were divided into four groups, including imiquimod (IMQ)-treated IL-18 KO group (n = 11) and WT group (n = 13) as well as their respectively gene-matched control mice (receiving vaseline; n = 12). PASI scores were used to evaluate psoriatic lesions in IMQ-treated mice. Pathological features and dermal cellular infiltration were investigated by hematoxylin and eosin staining. The levels of psoriasis-related cytokines including IL-23, IL-17, IL-12, IL-1β, IFNγ, IL-15, IL-27, and IL-4 were tested by real-time polymerase chain reaction (PCR). The protein level of IL-1β, IL-27, CXCL1, and Ly6 g were investigated by immunohistochemistry (IHC). RESULTS: Acanthosis (98.46 ± 14.12 vs. 222.68 ± 71.10 μm, P < 0.01) and dermal cell infiltration (572.25 ± 47.45 vs. 762.47 ± 59.59 cells/field, P < 0.01) were significantly milder in IMQ-induced IL-18 KO mice compared with that in WT mice. IMQ-induced IL-18 KO mice manifested larger areas of Munro microabscesses (11,467.83 ± 5112.09 vs. 4093.19 ± 2591.88 μm, P < 0.01) and scales (100,935.24 ± 41,167.77 vs. 41,604.41 ± 14,184.10 μm, P < 0.01) as compared with WT mice. In skin lesions of IL-18 KO mice, the expressions of IL-1β, IL-4, and IL-27 were all significantly upregulated but IL-17 was decreased. Histologically, strong positive signals of Ly6g were observed within the epidermis of IL-18 KO mice but expressions of CXCL1 were decreased. CONCLUSIONS IL-18 may exacerbate prominent inflammation and influence pathological features in IMQ-induced mouse model of psoriasis. IL-18 may upregulate pro-inflammatory cytokines and reduce protective cytokines, thus aggravating psoriatic inflammation. In addition, IL-18 may be involved in the formation of Munro microabscesses and scales.
Animals ; Chemokine CXCL1 ; metabolism ; Cytokines ; metabolism ; Disease Models, Animal ; Imiquimod ; toxicity ; Interleukin-17 ; metabolism ; Interleukin-18 ; metabolism ; Mice ; Mice, Knockout ; Psoriasis ; chemically induced ; genetics ; metabolism ; Skin ; immunology ; metabolism

This study aims to explore the effect of "Trichosanthis Fructus-Allii Macrostemonis" combination(GX) on the activation of NOD-, LRR-, and pyrin domain-containing protein 3(NLRP3) inflammasome, the release of inflammatory cytokines, and the level of autophagy in RAW264.7 macrophage damaged by lipopolysaccharide(LPS), and the mechanism of GX against inflammatory response in macrophages. To be specific, LPS was used to induce the injury of RAW264.7 cells. Cell Counting Kit-8(CCK-8) assay was employed to measure the survival rate of cells, and Western blot to detect the protein expression of NLRP3, apoptosis-associated speck-like protein(ASC), cysteine-aspartic acid protease(caspase)-1, interleukin(IL)-18, IL-1β, microtubule-associated protein light chain 3(LC3)-Ⅱ, and selective autophagy junction protein p62/sequestosome 1 in RAW264.7 macrophages. ELISA was used to measure the levels of IL-18 and IL-1β in RAW264.7 cells. Transmission electron microscopy was applied to observe the number of autophagosomes in RAW264.7 cells. Immunofulourescence staining was used to detect the expression of LC3-Ⅱ and p62 in RAW264.7 cells. The result showed that GX significantly reduced the protein expression of NLRP3, ASC, and caspase-1 in RAW264.7 cells, significantly increased the protein expression of LC3Ⅱ, decreased the expression of p62, significantly inhibited the secretion of IL-18 and IL-1β, significantly increased the number of autophagosomes, significantly enhanced the immunofluorescence of LC3Ⅱ, and reduced the immunofluorescence of p62. Furthermore, 3-methyladenine(3-MA) could reverse the inhibitory effect of GX on NLRP3, ASC, and caspase-1 and reduce the release of IL-18 and IL-1β. In summary, GX can increase of the autophagy activity of RAW264.7 and inhibit the activation of NLRP3 inflammasome, thereby reducing the release of inflammatory cytokines and suppressing inflammatory response in macrophages.
Inflammasomes/metabolism* ; NLR Family, Pyrin Domain-Containing 3 Protein/metabolism* ; Interleukin-18/metabolism* ; Lipopolysaccharides/pharmacology* ; Macrophages ; Cytokines/metabolism* ; Caspase 1/metabolism* ; Autophagy ; Interleukin-1beta/metabolism*

OBJECTIVETo evaluate the role of interleukin (IL)-18 and IL-18 receptor (IL-18R) in the predominant Th1 type cytokine response in patients with immune thrombocytopenia (ITP).

METHODSFifteen patients with active phase ITP, eighteen in remission and thirteen healthy controls were enrolled in this study. T-bet and GATA-3 mRNA levels in peripheral blood mononucleated cells (PBMNC) were measured by reverse transcriptase polymerase chain reaction (RT-PCR); the plasma IL-18 level by enzyme linked immunosorbent assay (ELISA), the expression of IL-18R on CD3(+) lymphocytes and total lymphocytes by flow cytometry(FCM).

RESULTSThe T-bet mRNA levels in patients with active phase ITP was 3.572 fold as much as that in the controls (P < 0.05), while the GATA-3 mRNA levels were 0.378 fold of that in controls (P < 0.05). The levels of plasma IL-18 and IL-18R on CD3(+) lymphocytes were significantly increased in active phase ITP than in remission phase and controls. There was no difference in ratio of T-bet/GATA-3 between remitted ITP and controls and so was for T-bet mRNA, GATA-3 mRNA, plasma IL-18 and IL-18R on CD3(+) lymphocytes.

CONCLUSIONITP as a disease of Th1-dominant response there is an unbalance between T-bet and GATA-3 in its active phase; IL-18 and IL-18R being upregulated.

Adolescent ; Adult ; Aged ; Case-Control Studies ; Female ; GATA3 Transcription Factor ; metabolism ; Humans ; Interleukin-18 ; immunology ; metabolism ; Male ; Middle Aged ; Purpura, Thrombocytopenic, Idiopathic ; immunology ; metabolism ; Receptors, Interleukin-18 ; immunology ; metabolism ; T-Box Domain Proteins ; metabolism ; Th1 Cells ; immunology ; metabolism ; Young Adult