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1: Archives of dermatological research, 2010 Sep 8,
Serum CCL23 levels are increased in patients with systemic sclerosis.

[Abstract]The aim of this study is to determine serum CCL23 levels and their clinical associations in patients with systemic sclerosis (SSc). Serum CCL23 levels were examined by ELISA in 66 patients with SSc, 20 patients with systemic lupus erythematosus, 20 patients with dermatomyositis, and 33 healthy individuals. Serum CCL23 levels were elevated in SSc patients (389.1 +/- 199.2 pg/mL) compared with healthy individuals (94.1 +/- 85.6 pg/mL; P < 0.001) and patients with systemic lupus erythematosus (43.4 +/- 39.3 pg/mL; P < 0.001) or dermatomyositis (132.1 +/- 104.5 pg/mL; P < 0.001). Among SSc patients, there were no differences in serum CCL23 levels between those with limited cutaneous SSc and those with diffuse cutaneous SSc. SSc patients with elevated CCL23 levels were found to have shorter disease duration than those with normal CCL23 levels (P < 0.001). Furthermore, raised CCL23 levels were associated with a higher frequency of pulmonary arterial hypertension (P < 0.05). The results show that serum CCL23 level was increased in the early phase of SSc. CCL23 could be associated with induction of SSc and as such would be a serologically useful marker for disease activity.

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2: Cytokine, 2010 Jan 22,
CKbeta8/CCL23 and its isoform CKbeta8-1 induce up-regulation of cyclins via the G(i)/G(o) protein/PLC/PKCdelta/ERK leading to cell-cycle progression.

[Abstract]CKbeta8/CCL23 is a CC chemokine and alternative splicing of the CKbeta8 gene produces two mRNAs that encode CKbeta8 and its isoform CKbeta8-1. Chemokines play a critical role in leukocyte trafficking and development of inflammation and chemokines are also known to be involved in cell proliferation. To investigate participation of CKbeta8 and CKbeta8-1 in cell proliferation, we examined the effects of CKbeta8 and CKbeta8-1 in the cell cycle. Both CKbeta8 and CKbeta8-1 induced cell-cycle progression. We next investigated whether MAPKs are involved in CKbeta8- and CKbeta8-1-induced cell proliferation. CKbeta8- and CKbeta8-1-stimulated cells showed phosphorylation of ERK1/2 and an inhibitor study indicated that CKbeta8- and CKbeta8-1-induced activation of ERK1/2 is mediated by the G(i)/G(o) protein, PLC, and PKCdelta. CKbeta8 and CKbeta8-1 regulated expression of the cell cycle regulators cyclin D(3) and cyclin B(1,) and the immediate early response gene products c-Myc and Egr-1. These results indicate that both CKbeta8 and CKbeta8-1 are involved in cell proliferation by modulating the cell cycle regulators.

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3: Life sciences, 2009 Nov 28,
CKbeta8/CCL23 induces cell migration via the G(i)/G(o) protein/PLC/PKCdelta/NF-kappaB and is involved in inflammatory responses.

[Abstract]AIMS: CKbeta8/CCL23 is a CC chemokine and alternative splicing of the CKbeta8 gene produces two mRNAs that encode CKbeta8 and its isoform CKbeta8-1. Although it has been reported that CKbeta8 and CKbeta8-1 are implicated in leukocyte trafficking and development of inflammation, the exact roles of these two chemokines in immune responses and the associated chemotaxis signaling are still obscure. MAIN METHODS: To understand the mechanism of CKbeta8- and CKbeta8-1-induced chemotaxis signaling, we examined the chemotactic activities of osteogenic sarcoma cells expressing CC chemokine receptor 1 in response to CKbeta8 and CKbeta8-1. We also examined involvement of CKbeta8 and CKbeta8-1 in inflammatory responses by determining the mRNA expression of pro-inflammatory molecules induced by two chemokines and expressions of these chemokines in foam cells. KEY FINDINGS: Results from a chemotaxis assay using various inhibitors for signaling molecules showed that the chemotaxis signal pathway induced by both CKbeta8 and CKbeta8-1 was mediated via the G(i)/G(o) protein, phospholipase C (PLC) and protein kinase Cdelta (PKCdelta). Treatment with a nuclear factor kappaB (NF-kappaB) inhibitor reduced the chemotactic activities of CKbeta8 and CKbeta8-1, and NF-kappaB was activated in response to CKbeta8 and CKbeta8-1. In addition, CKbeta8 and CKbeta8-1 increased mRNA expression of pro-inflammatory cytokines and adhesion molecules. The mRNA levels of CKbeta8 and CKbeta8-1 were increased in foam cells. SIGNIFICANCE: These results indicate that both CKbeta8 and CKbeta8-1 transduce the chemotaxis signal through the G(i)/G(o) protein, PLC, PKCdelta, and NF-kappaB, and that CKbeta8 and CKbeta8-1 probably play important roles in inflammatory diseases such as atherosclerosis.

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4: Biochemical and biophysical research communications, 2009 Apr 24, 382(1)
CCL23 up-regulates expression of KDR/Flk-1 and potentiates VEGF-induced proliferation and migration of human endothelial cells.

[Abstract]CCL23 is a CC chemokine and exerts its biological activities on endothelial cells as well as on immune cells through CCR1. We investigated the potential effect of CCL23 on expression of KDR/Flk-1 receptor in endothelial cells. PCR, confocal microscope and Western blot analysis revealed that CCL23 up-regulated KDR/Flk-1 mRNA and protein levels in endothelial cells. A reporter assay indicated that CCL23-induced KDR/Flk-1 expression primarily occurred at the transcriptional level. In addition, CCL23 stimulated phosphorylation of SAPK/JNK, and an inhibitor of SAPK/JNK blocks the CCL23-induced KDR/Flk-1 expression. Furthermore, VEGF-induced ERK phosphorylation was stimulated by CCL23. Finally, CCL23 promoted VEGF-induced endothelial proliferation and migration, which were correlated with the maximal stimulation of KDR/Flk-1 expression by CCL23. Taken together, these findings suggest that CCL23 results in up-regulation of KDR/flk-1 receptor gene transcription and protein expression and that KDR/Flk-1 up-regulation induced by CCL23 may contribute to potentiation of VEGF action in angiogenesis.

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5: Arthritis and rheumatism, 2008 Aug, 58(8)
Potential novel biomarkers of disease activity in rheumatoid arthritis patients: CXCL13, CCL23, transforming growth factor alpha, tumor necrosis factor receptor superfamily member 9, and macrophage colony-stimulating factor.

[Abstract]OBJECTIVE: To determine whether the plasma levels of a range of inflammatory proteins have utility as biomarkers of disease activity in rheumatoid arthritis (RA) patients. METHODS: Plasma proteins (n = 163) were profiled in 44 patients with RA diagnosed according to the American College of Rheumatology 1987 criteria (22 with active and 22 with quiescent disease) and in 16 age- and sex-matched healthy controls. The utility of a subset of differentially expressed proteins as predictors of RA disease activity was investigated using partial least-squares discriminant analysis, and their response to therapeutic intervention was evaluated in plasma from an additional cohort of 16 patients with active RA treated with anti-tumor necrosis factor alpha (anti-TNFalpha). RESULTS: The protein profiling study identified 25 proteins that were differentially expressed in plasma samples from patients with active RA (P for the false discovery rate < or = 0.01) compared with those with quiescent RA, including the previously described interleukin-6 (IL-6), oncostatin M, and IL-2, and the 5 less-established markers macrophage colony-stimulating factor (M-CSF), tumor necrosis factor receptor superfamily member 9, CCL23, transforming growth factor alpha, and CXCL13. Systemic levels of these 5 markers correlated with the C-reactive protein level, erythrocyte sedimentation rate, rheumatoid factor level, tender joint count in 68 joints, and Disease Activity Score in 28 joints (DAS28), and their combined plasma levels were shown to be good predictors of disease activity (kappa = 0.64). In anti-TNFalpha-treated RA patients, plasma levels of CXCL13 were reduced after 1 and 7 days of therapy, and levels of CCL23, M-CSF, and CXCL13 showed a statistically significant positive correlation with the DAS28 score. CONCLUSION: This exploratory study for biomarker discovery led to the identification of several proteins predictive of RA disease activity that may be useful in the definition of disease subphenotypes and in the measurement of response to therapy in clinical studies.

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6: Zhongguo shi yan xue ye xue za zhi / Zhongguo bing li sheng li xue hui = Journal of experimental hematology / Chinese Association of Pathophysiology, 2007 Jun, 15(3)
[Effect of CCL23/myeloid progenitor inhibitory factor 1 (MPIF-1) on the proliferation, apoptosis and differentiation of U937 cells]

[Abstract]CCL23 is a human CC chemokine with potential suppression effects on both human and murine myeloid progenitor cells both in vitro and in vivo, and only expressed and released by dendritic cells differentiated from monocytes in blood cells. However, recent study has shown that CCL23 was over-expressed in bone marrow and peripheral blood cells from pediatric patients with acute myeloid leukemia (AML). In order to investigate the effects of CCL23 on the development, therapy and prognosis of leukemia, the U937 cells, a leukemic cell strain, were adopted and cultured with rhCCL23 for 72 hours. The cell proliferation and apoptosis rate were detected by Cell Counting Kit-8 and FITC-AnnexinV/PI respectively; the morphologic changes and the expression of CCR1 (the only receptor of CCL23 known by now) were observed during the differentiation process. The results showed that no obvious effect on the proliferation, apoptosis and differentiation of U937 was found by using CCL23 alone (P > 0.05), but cultured in combination with CCL23 and PMA, the differentiation of U937 cells were promoted remarkably, during which the CCR1 expression increased (P < 0.05). It is concluded that CCL23 alone did not inhibit the proliferation and differentiation of U937, while its use in combination with PMA may possess synergistic effect on inducting differentiation of U937 through the increase of receptor CCR1 expression.

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7: Journal of immunology (Baltimore, Md. : 1950), 2007 Jun 1, 178(11)
Proinflammatory proteases liberate a discrete high-affinity functional FPRL1 (CCR12) ligand from CCL23.

[Abstract]Most chemokines have been found to bind to and signal through single or highly related chemokine receptors. However, a single chemokine protein, a processed form of the alternatively spliced CCL23 (CKbeta8/MPIF-1) gene product, potently engages both the "classical" chemokine receptor CCR1, as well as FPRL1, a type of pattern recognition receptor on innate immune cells. However, the mechanism by which the alternative form of CCL23 is processed is unknown. In this study, we show that proteases associated with inflammation cleave CCL23 immediately N-terminal to the 18-residue domain encoded by the alternatively spliced nucleotides, resulting in potent CCR1 and FPRL1 activity. The proteases also cleave CCL23 immediately C-terminal to the inserted domain, producing a typical CC chemokine "body" containing even further-increased CCR1 potency and a released approximately 18-aa peptide with full FPRL1 activity but no activity for CCR1. This peptide, which we term SHAAGtide, is by itself an attractant of monocytes and neutrophils in vitro, recruits leukocytes in vivo, and is 50- to 100-fold more potent than all other natural agents posited to act on FPRL1. The appearance of SHAAGtide appears to be transient, however, as the proinflammatory proteases subsequently cleave within the peptide, abolishing its activity for FPRL1. The sequential activation of a transient FPRL1 ligand and a longer-lived CCR1 ligand within a single chemokine may have important consequences for the development of inflammation or the link between innate and adaptive immunity.

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8: Journal of immunology (Baltimore, Md. : 1950), 2007 Apr 1, 178(7)
CCL23 expression is induced by IL-4 in a STAT6-dependent fashion.

[Abstract]The chemokine CCL23 is primarily expressed in cells of the myeloid lineage but little information about its regulation is available. In this study, it is demonstrated that IL-4 and IL-13 induced CCL23 expression in human peripheral blood monocytes. GM-CSF had no effect on its own but synergized with IL-4, but not IL-13. CCL23 promoter reporter gene constructs were sensitive to IL-4 stimulation in the presence of the transcription factor STAT6. A canonical STAT6 binding site in the promoter region of the CCL23 gene was critical for the IL-4-inducible phenotype because reporter plasmids with a defective STAT6 binding site were unable to respond to IL-4 stimulation. In addition, two tandem copies of the STAT6 site conferred cytokine responsiveness to a heterologous minimal promoter. Furthermore, IL-4 inducibility of the CCL23 promoter was dependent on the absence of a negatively acting cis-element downstream of the STAT6 binding site. The negative function of this element was operative also on heterologous IL-4-inducible promoters. CCL23 was also expressed in skin from patients suffering from atopic dermatitis at higher levels than in normal individuals. However, no correlation between CCL23 expression in the serum and IgE levels as a diagnostic marker for atopy was found. Collectively, these data suggest a link between the inducible phenotype of CCL23 expression in monocytes by the prototype Th2 molecule pair IL-4/STAT6 and the increased number of CCL23-expressing cells in skin of atopic dermatitis patients.

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9: Biochemical and biophysical research communications, 2006 Feb 10, 340(2)
Human CC chemokine CCL23 enhances expression of matrix metalloproteinase-2 and invasion of vascular endothelial cells.

[Abstract]Human CCL23 (also known as CKbeta8, MPIF-1, or MIP-3) has been recently reported to induce endothelial cell migration and tube formation via CCR1. Matrix metalloproteinases (MMPs) are involved in the degradation of the extracellular matrix and also appear to play critical roles in angiogenesis. In the present study, we have demonstrated that CCL23 enhances the expression of MMP-2 mRNA and protein levels in endothelial cells in a dose-dependent manner, but has no effect on the expression levels of MMP-9, TIMP-1, TIMP-2, and MT1-MMP. CCL23 was shown to dose-dependently activate the expression of the MMP-2/Luc reporter gene, thereby indicating that it stimulates the transcription of the MMP-2 gene. Vascular endothelial cells, when exposed to CCL23, showed a marked ability to invade through a 3D Matrigel. This increase in invasion was also correlated with enhancements in the expression and activity of MMP-2. Neutralization with anti-CCL23 and anti-CCR1 antibodies, as well as the heat-induced inactivation of CCL23, resulted in a blockage of the CCL23-activated invasion, indicating that the invasion of HUVECs was induced by CCL23 specifically. Furthermore, we showed that the CCL23-induced invasion was inhibited by MMP inhibitors such as GM6001 and a specific MMP-2 Inhibitor I. Our results indicate that CCL23 may play a direct role in angiogenesis, via the upregulation of MMP-2 expression.

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10: Journal of cellular physiology, 2000 May, 183(2)
CKbeta-8 [CCL23], a novel CC chemokine, is chemotactic for human osteoclast precursors and is expressed in bone tissues.

[Abstract]We have previously demonstrated that a tartrate-resistant acid phosphatase (TRAP)-positive subpopulation of mononuclear cells isolated from collagenase digests of human osteoclastoma tissue exhibits an osteoclast phenotype and can be induced to resorb bone. Using these osteoclast precursors as a model system, we have assessed the chemotactic potential of 16 chemokines. Three CC chemokines, the recently described CKbeta-8, RANTES, and MIP-1alpha elicited significant chemotactic responses. In contrast, 10 other CC chemokines (MIP-1beta, MCP-1, MCP-2, MCP-3, MCP-4, HCC-1, eotaxin-2, PARC, SLC, ELC) and 3 CXC chemokines (IL-8, GROalpha, SDF-1) were inactive. None of these chemokines showed any chemotactic activity for either primary osteoblasts derived from human bone explants or the osteoblastic MG-63 cell line. The identity of the osteoclast receptor that mediates the chemotactic response remains to be established. However, all three active chemokines have been reported to bind to CCR1 and cross-desensitization studies demonstrate that RANTES and MIP-1alpha can partially inhibit the chemotactic response elicited by CKbeta-8. CKbeta-8, the most potent of the active CC chemokines (EC(max) 0.1-0.3 nM), was further characterized with regard to expression in human bone and cartilage. Although expression is not restricted to these tissues, CKbeta-8 mRNA was shown to be highly expressed in osteoblasts and chondrocytes in human fetal bone by in situ hybridization. In addition, CKbeta-8 protein was shown to be present in human osteophytic tissue by immunolocalization. These observations suggest that CKbeta-8, and perhaps other chemokines, may play a role in the recruitment of osteoclast precursors to sites of bone resorption.