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Proceedings of the National Academy of... Apr 2012T-cell-derived soluble factors that inhibit both X4 and R5 HIV are recognized as important in controlling HIV. Whereas three β chemokines, regulated-on-activation...
T-cell-derived soluble factors that inhibit both X4 and R5 HIV are recognized as important in controlling HIV. Whereas three β chemokines, regulated-on-activation normal T-cell expressed and secreted (RANTES), macrophage inflammatory protein (MIP)-1α, and MIP-1β, account for the suppression of R5 HIV by blockade of HIV entry, the major components responsible for the inhibition of X4 HIV strains have not been identified previously. We identify these factors primarily as a mixture of three β chemokines [macrophage-derived chemokine (MDC), thymus and activation-regulated chemokine (TARC), and I-309] and two RNases (angiogenin and RNase 4) of lesser potency and show that in a clade B population, some correlate with clinical status and are produced by both CD4(+) and CD8(+) T cells (chemokines, angiogenin) or only by CD8(+) T cells (RNase 4). The antiviral mechanisms of these HIV X4-suppressive factors differ from those of the previously described HIV R5-suppressive β chemokines.
Topics: Anti-HIV Agents; Chemokines, CC; Dose-Response Relationship, Drug; HIV; Humans; Ribonucleases; Solubility; T-Lymphocytes; Virus Replication
PubMed: 22431590
DOI: 10.1073/pnas.1202240109 -
The Journal of Clinical Investigation Oct 1999
Review
Topics: Animals; Asthma; Bronchial Hyperreactivity; Calcium; Chemokine CCL11; Chemokines; Chemokines, CC; Cytokines; Humans; Receptors, Chemokine
PubMed: 10525033
DOI: 10.1172/JCI8125 -
Molecular Oncology Oct 2015Elevated levels of chemokine receptor CCR9 expression in solid tumors may contribute to poor patient prognosis. In this study, we characterized a novel CCR9-mediated...
Elevated levels of chemokine receptor CCR9 expression in solid tumors may contribute to poor patient prognosis. In this study, we characterized a novel CCR9-mediated pathway that promotes pancreatic cancer cell invasion and drug resistance, indicating that CCR9 may play a critical role in cancer progression through activation of β-catenin. We noted that the CCL25/CCR9 axis in pancreatic cancer cells induced the activation of β-catenin, which enhanced cell proliferation, invasion, and drug resistance. CCR9-mediated activation of β-catenin and the resulting downstream effects were effectively inhibited by blockade of the PI3K/AKT pathway, but not by antagonism of Wnt. Importantly, we discovered that CCR9/CCL25 increased the lethal dose of gemcitabine, suggesting decreased efficacy of anti-cancer drugs with CCR9 signaling. Through in silico computational modeling, we identified candidate CCR9 antagonists and tested their effects on CCR9/β-catenin regulation of cell signaling and drug sensitivity. When combined with gemcitabine, it resulted in synergistic cytotoxicity. Our results show that CCR9/β-catenin signaling enhances pancreatic cancer invasiveness and chemoresistance, and may be a highly novel therapeutic target.
Topics: Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Chemokines, CC; Computational Biology; Drug Discovery; Drug Screening Assays, Antitumor; Drug Synergism; Humans; Molecular Docking Simulation; Molecular Targeted Therapy; Neoplasm Invasiveness; Pancreatic Neoplasms; Receptors, CCR; Signal Transduction; Wnt Signaling Pathway; beta Catenin
PubMed: 26003048
DOI: 10.1016/j.molonc.2015.04.012 -
The Journal of Biological Chemistry Feb 2012Leukocyte migration and activation is orchestrated by chemokines, the cleavage of which modulates their activity and glycosaminoglycan binding and thus their roles in...
Leukocyte migration and activation is orchestrated by chemokines, the cleavage of which modulates their activity and glycosaminoglycan binding and thus their roles in inflammation and immunity. Early research identified proteolysis as a means of both activating or inactivating CXC chemokines and inactivating CC chemokines. Recent evidence has shown activating cleavages of the monocyte chemoattractants CCL15 and CCL23 by incubation with synovial fluid, although the responsible proteases could not be identified. Herein we show that CCL15 is processed in human synovial fluid by matrix metalloproteinases (MMPs) and serine proteases. Furthermore, a family-wide investigation of MMP processing of all 14 monocyte-directed CC chemokines revealed that each is precisely cleaved by one or more MMPs. By MALDI-TOF-MS, 149 cleavage sites were sequenced including the first reported instance of CCL1, CCL16, and CCL17 proteolysis. Full-length CCL15-(1-92) and CCL23-(1-99) were cleaved within their unique 31 and 32-amino acid residue extended amino termini, respectively. Unlike other CCL chemokines that lose activity and become receptor antagonists upon MMP cleavage, the prominent MMP-processed products CCL15-(25-92, 28-92) and CCL23-(26-99) are stronger agonists in calcium flux and Transwell CC receptor transfectant and monocytic THP-1 migration assays. MMP processing of CCL16-(1-97) in its extended carboxyl terminus yields two products, CCL16-(8-77) and CCL16-(8-85), with both showing unexpected enhanced glycosaminoglycan binding. Hence, our study reveals for the first time that MMPs activate the long amino-terminal chemokines CCL15 and CCL23 to potent forms that have potential to increase monocyte recruitment during inflammation.
Topics: Amino Acid Sequence; Calcium; Cell Line; Chemokines, CC; Chemotaxis; Enzyme Activation; Glycosaminoglycans; Heparin; Humans; Kinetics; Ligands; Macrophage Inflammatory Proteins; Macrophages; Matrix Metalloproteinases; Molecular Sequence Data; Monocytes; Protein Binding; Substrate Specificity; Synovial Fluid
PubMed: 22147696
DOI: 10.1074/jbc.M111.314609 -
The Journal of Investigative Dermatology Mar 2007Besides their microbicidal functions, human beta-defensins (hBD) and LL-37 activate different immune and inflammatory cells, and their expression is enhanced in inflamed...
Besides their microbicidal functions, human beta-defensins (hBD) and LL-37 activate different immune and inflammatory cells, and their expression is enhanced in inflamed skin and cutaneous wound sites. To protect against pathogens, the skin produces antimicrobial peptides including hBDs and LL-37. Therefore, the aim of our study was to investigate whether hBDs participate in cutaneous inflammation and wound healing by inducing keratinocyte migration, proliferation, and production of proinflammatory cytokines/chemokines. We found that hBD-2, -3, and -4 but not hBD-1 stimulated human keratinocytes to increase their gene expression and protein production of IL-6, IL-10, IP-10, monocyte chemoattractant protein-1, macrophage inflammatory protein-3alpha, and RANTES. This stimulatory effect was markedly suppressed by pertussis toxin and U-73122, inhibitors for G protein and phospholipase C, respectively. We also demonstrated that hBDs elicited intracellular Ca2+ mobilization, and increased keratinocyte migration, and proliferation. In addition, these peptides induced phosphorylation of EGFR, signal transducer and activator of transcription (STAT)1, and STAT3, which are intracellular signaling molecules involved in keratinocyte migration and proliferation. In our study, inhibition of these molecules significantly reduced hBD-mediated keratinocyte migration and proliferation. In conclusion, this study provides evidence that human antimicrobial peptides may be involved in skin immunity through stimulating cytokine/chemokine production, and participate in wound healing by promoting keratinocyte migration and proliferation.
Topics: Antimicrobial Cationic Peptides; Cell Movement; Cell Proliferation; Chemokine CCL20; Chemokine CCL5; Chemokines; Chemokines, CC; Cytokines; Epidermal Cells; Estrenes; Gene Expression Regulation; Humans; Inflammation; Keratinocytes; Macrophage Inflammatory Proteins; Pyrrolidinones; Signal Transduction; beta-Defensins
PubMed: 17068477
DOI: 10.1038/sj.jid.5700599 -
Infection and Immunity Sep 1999In the present study, we describe the ability of Trypanosoma cruzi trypomastigotes to stimulate the synthesis of beta-chemokines by macrophages. In vivo infection with...
In the present study, we describe the ability of Trypanosoma cruzi trypomastigotes to stimulate the synthesis of beta-chemokines by macrophages. In vivo infection with T. cruzi led to MIP-1alpha, RANTES, and JE/MCP1 mRNA expression by cells from peritoneal inflammatory exudate. In addition, in vitro infection with T. cruzi resulted in expression of beta-chemokine MIP-1alpha, MIP-1beta, RANTES, and JE mRNA by macrophages. The expression of the beta-chemokine MIP-1alpha, MIP-1beta, RANTES, and JE proteins by murine macrophages cultured with trypomastigote forms of T. cruzi was confirmed by immunocytochemistry. Interestingly, macrophage infection with T. cruzi also resulted in NO production, which we found to be mediated mainly by beta-chemokines. Hence, treatment with anti-beta-chemokine-specific neutralizing antibodies partially inhibited NO release by macrophages incubated with T. cruzi parasites. Further, the addition of the exogenous beta-chemokines MIP-1alpha, MIP-1beta, RANTES, and JE/MCP-1 induced an increased T. cruzi uptake, leading to enhanced NO production and control of parasite replication in a dose-dependent manner. L-NMMA, a specific inhibitor of the L-arginine-NO pathway, caused a decrease in NO production and parasite killing when added to cultures of macrophages stimulated with beta-chemokines. Among the beta-chemokines tested, JE was more potent in inhibiting parasite growth, although it was much less efficient than gamma interferon (IFN-gamma). Nevertheless, JE potentiates parasite killing by macrophages incubated with low doses of IFN-gamma. Together, these results suggest that in addition to their chemotactic activity, murine beta-chemokines may also contribute to enhancing parasite uptake and promoting control of parasite replication in macrophages and may play a role in resistance to T. cruzi infection.
Topics: Animals; Cells, Cultured; Chemokine CCL2; Chemokine CCL3; Chemokine CCL4; Chemokine CCL5; Chemokines, CC; Female; Macrophage Activation; Macrophage Inflammatory Proteins; Macrophages; Mice; Mice, Inbred C3H; Nitric Oxide; Trypanosoma cruzi
PubMed: 10456936
DOI: 10.1128/IAI.67.9.4819-4826.1999 -
Cytokine Sep 2017Rheumatoid arthritis (RA) is a destructive and chronic autoimmune inflammatory disease. Synovial inflammation is a major feature of RA and is associated with leukocyte...
Rheumatoid arthritis (RA) is a destructive and chronic autoimmune inflammatory disease. Synovial inflammation is a major feature of RA and is associated with leukocyte recruitment. Leukocytes cross the endothelial cells (ECs) into the synovial tissue and fluid and this migration is mediated via a range of chemokines and adhesion molecules on the ECs. As important mediators of leukocyte extravasation, a number of chemokines from each of the chemokine families have been established as expressed in the RA joint. However, as little information is available on which chemokines are expressed/presented by the ECs themselves, the purpose of the study was to ascertain which of the CC chemokines were localised in RA ECs. Immunofluoresence was used to assess the presence of the CC-family chemokines in RA synovial ECs using von-Willebrand factor (VWF) as a pan-endothelial marker and a range of human chemokine antibodies. The percentage of VWF positive vessels which were positive for the chemokines was determined. The presence of the four most highly expressed novel chemokines were further investigated in non-RA synovial ECs and the sera and synovial fluid (SF) from patients with RA and osteoarthritis (OA). Statistical analysis of immunofluorescence data was carried out by Student's t-test. For analysis of ELISA data, Kruskal-Wallis ANOVA followed by Dunn's multiple comparison test was utilised to analyse differences in sera and SF levels for each chemokine between RA and OA. Spearman rank correlations of sera and SF chemokine levels with a range of clinical variables were also performed. Chemokine detection varied, the least abundant being CCL27 which was present in 8.3% of RA blood vessels and the most abundant being CCL19 which was present in 80%. Of the 26 chemokines studied, 19 have not been previously observed in RA ECs. Four of these novel chemokines, namely CCL7, CCL14, CCL16 and CCL22 were present on ≥60% of vessels. CCL14 and CCL22 were shown to be increased in RA ECs compared to non-RA ECs, p=0.0041 and p=0.014 respectively. EC chemokines CCL7, CCL14, CCL16 and CCL22 also occurred in RA synovial fluid and sera as established by ELISA. CCL7 was shown to be significantly increased in sera and SF from RA patients compared to that from osteoarthritis (OA) patients (p<0.01), and to have a highly significant correlation with the level of anti-CCP (R=0.93, p=0.001). Less abundant chemokines shown to be present in RA ECs were CCL1-3, CCL5, CCL10-13, CCL15, CCL17, CCL18, CCL20, CCL21 and CCL23-28. In conclusion, this initial study is the first to show the presence of a number of CC chemokines in RA ECs. It provides evidence that further validation and investigation into the presence and functionality of these novel chemokines expressed at RA synovial ECs may be warranted.
Topics: Aged; Arthritis, Rheumatoid; Biomarkers; Chemokine CCL7; Chemokines, CC; Endothelial Cells; Female; Fluorescent Antibody Technique; Humans; Male; Middle Aged; Synovial Fluid; Synovial Membrane
PubMed: 28648867
DOI: 10.1016/j.cyto.2017.05.023 -
Microbiology and Immunology 2002Intestinal epithelial cells are the initial sites of host response to Clostridium difficile infection and can play a role in signaling the influx of inflammatory cells....
Intestinal epithelial cells are the initial sites of host response to Clostridium difficile infection and can play a role in signaling the influx of inflammatory cells. To further explore this role, the regulated expression and polarized secretion of CXC and CC chemokines by human intestinal epithelial cells were investigated. An expression of the CXC chemokines, including IL-8 and growth-related oncogene (GRO)-alpha, and the CC chemokine monocyte chemoattractant protein (MCP)-1 from HT-29 cells increased in the 1-6 hr following C. difficile toxin A stimulation, assessed by quantitative RT-PCR. In contrast, the expression of neutrophil activating protein-78 (ENA-78) was delayed for 18 hr. The up-regulated mRNA expression of chemokines was paralleled by the increase of protein levels. However, the expression of macrophage inflammatory protein (MIP)-1alpha, RANTES (regulated on activation normal T cells expressed and secreted), and interferon-gamma-inducible protein-10 (IP-10) was not changed in HT-29 or Caco-2 cells stimulated with toxin A. Upon stimulation of the polarized Caco-2 epithelial cells in a transwell chamber with toxin A, CXC and CC chemokines were released predominantly into the basolateral compartment. Moreover, the addition of IFN-gamma and TNF-alpha to toxin A stimulated Caco-2 cells increased the basolateral release of CC chemokine MCP-1. In contrast, IFN-gamma and TNF-alpha had no effect on the expression of the CXC chemokines IL-8 and GRO-alpha. These results suggest that a CXC and CC chemokine expression from epithelial cells infected with C. difficile may be an important factor in the mucosal inflammatory response.
Topics: Bacterial Toxins; Caco-2 Cells; Chemokine CCL2; Chemokine CCL3; Chemokine CCL4; Chemokine CCL5; Chemokines, CXC; Clostridioides difficile; Enterotoxins; Enzyme-Linked Immunosorbent Assay; HT29 Cells; Humans; Intestinal Mucosa; L-Lactate Dehydrogenase; Macrophage Inflammatory Proteins; RNA, Messenger; Reverse Transcriptase Polymerase Chain Reaction; Up-Regulation
PubMed: 12139393
DOI: 10.1111/j.1348-0421.2002.tb02704.x -
Proceedings of the National Academy of... May 2016CC chemokine ligand 5 (CCL5) and CCL3 are critical for immune surveillance and inflammation. Consequently, they are linked to the pathogenesis of many inflammatory...
CC chemokine ligand 5 (CCL5) and CCL3 are critical for immune surveillance and inflammation. Consequently, they are linked to the pathogenesis of many inflammatory conditions and are therapeutic targets. Oligomerization and glycosaminoglycan (GAG) binding of CCL5 and CCL3 are vital for the functions of these chemokines. Our structural and biophysical analyses of human CCL5 reveal that CCL5 oligomerization is a polymerization process in which CCL5 forms rod-shaped, double-helical oligomers. This CCL5 structure explains mutational data and offers a unified mechanism for CCL3, CCL4, and CCL5 assembly into high-molecular-weight, polydisperse oligomers. A conserved, positively charged BBXB motif is key for the binding of CC chemokines to GAG. However, this motif is partially buried when CCL3, CCL4, and CCL5 are oligomerized; thus, the mechanism by which GAG binds these chemokine oligomers has been elusive. Our structures of GAG-bound CCL5 and CCL3 oligomers reveal that these chemokine oligomers have distinct GAG-binding mechanisms. The CCL5 oligomer uses another positively charged and fully exposed motif, KKWVR, in GAG binding. However, residues from two partially buried BBXB motifs along with other residues combine to form a GAG-binding groove in the CCL3 oligomer. The N termini of CC chemokines are shown to be involved in receptor binding and oligomerization. We also report an alternative CCL3 oligomer structure that reveals how conformational changes in CCL3 N termini profoundly alter its surface properties and dimer-dimer interactions to affect GAG binding and oligomerization. Such complexity in oligomerization and GAG binding enables intricate, physiologically relevant regulation of CC chemokine functions.
Topics: Binding Sites; Chemokine CCL3; Chemokine CCL5; Dimerization; Glycosaminoglycans; Humans; Protein Binding; Protein Conformation; Structure-Activity Relationship
PubMed: 27091995
DOI: 10.1073/pnas.1523981113 -
The European Respiratory Journal Aug 2003Eosinophil recruitment into the airways is a feature of asthma in children. However, the mechanisms by which these cells migrate into the airways are not fully...
Eosinophil recruitment into the airways is a feature of asthma in children. However, the mechanisms by which these cells migrate into the airways are not fully understood. The present study investigated the presence of the eosinophil-activating chemokines regulated on activation, normal T-cell expressed and secreted (RANTES), monocyte chemotactic proteins (MCP)-3 and -4, and eotaxins-1 and -2 in the bronchoalveolar lavage (BAL) fluid obtained from both asthmatic (n=10, age 6-10 yrs) and normal children (n=10, age 5-10 yrs). Measurements of chemokines in BAL fluid showed that levels of RANTES, MCPs-3 and -4, and eotaxins-1 and -2 were significantly increased in fluid obtained from asthmatic children when compared with normal children. Among the different chemokines, RANTES was the cytokine released in greatest quantities in BAL fluid from asthmatic children. There was a significant correlation between the concentrations of MCP-4 and eosinophil numbers in BAL fluid and a trend between both chemokines MCP-3 and eotaxin-2 and eosinophils. Interestingly, the levels of most chemokines correlated with one another. These findings suggest that RANTES monocyte chemotactic proteins-3 and -4, and eotaxins-1 and -2 may regulate eosinophil trafficking into the airways of asthmatic children in a coordinated manner.
Topics: Asthma; Bronchoalveolar Lavage Fluid; Chemokine CCL11; Chemokine CCL24; Chemokine CCL5; Chemokine CCL7; Chemokines, CC; Child; Child, Preschool; Cytokines; Eosinophils; Female; Humans; Leukocyte Count; Male; Monocyte Chemoattractant Proteins
PubMed: 12952266
DOI: 10.1183/09031936.03.00084802