Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:3.4.24.59 (MIP)
 4,906 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A full high-resolution three-dimensional solution structure of the monocyte chemoattractant protein-1 (MCP-1 or MCAF) homodimer has been determined by heteronuclear multidimensional NMR. MCP-1 is a member of a family of small proteins which play a crucial role in immune surveillance by orchestrating the recruitment of specific leukocytes to areas of immune challenge. The protein was uniformly isotopically enriched with 13C and 15N by expression in Escherichia coli, and complete sequence-specific resonance assignments were obtained by a combination of heteronuclear double- and triple-resonance experiments. The secondary structure was deduced from characteristic patterns of NOEs, 13 C alpha/beta chemical shifts, measurements of 3JHNH alpha scalar couplings, and patterns of slowly exchanging amide protons. Because MCP-1 forms symmetrical homodimers, additional experiments were carried out to unambiguously establish the quaternary contacts. NOEs from these novel experiments were merged with more traditional heteronuclear separated NOE measurements in an iterative strategy to partition the restraints between explicit inter/intrasubunit contacts and a class wherein both were retained as ambiguous. With more than 30 restraints per residue, the three-dimensional structure is well-defined with a backbone rmsd of 0.37 A to the mean over residues 5-69 of the dimer. We compare the structure with those recently reported for the related chemokines MIP-1 beta and RANTES and highlight the differences in terms of receptor specificity and function as well as interpret the known biological activity data of MCP-1 mutants.
 ...
PMID:Heteronuclear (1H, 13C, 15N) NMR assignments and solution structure of the monocyte chemoattractant protein-1 (MCP-1) dimer. 863 5

Although there is a mounting body of evidence that eosinophils are recruited to sites of allergic inflammation by a number of beta-chemokines, particularly eotaxin and RANTES, the receptor that mediates these actions has not been identified. We have now cloned a G protein-coupled receptor, CC CKR3, from human eosinophils which, when stably expressed in AML14.3D10 cells bound eotaxin, MCP-3 and RANTES with Kds of 0.1, 2.7 and 3.1 nM, respectively. CC CKR3 also bound MCP-1 with lower affinity, but did not bind MIP-1 alpha or MIP-1 beta. Eotaxin, RANTES, and to a lessor extent MCP-3, but not the other chemokines, activated CC CKR3 as determined by their ability to stimulate a Ca(2+) -flux. Competition binding studies on primary eosinophils gave binding affinities for the different chemokines which were indistinguishable from those measured with CC CKR3. Since CC CKR3 is prominently expressed in eosinophils we conclude that CC CKR3 is the eosinophil eotaxin receptor. Eosinophils also express a much lower level of a second chemokine receptor, CC CKR1, which appears to be responsible for the effects of MIP-1 alpha.
 ...
PMID:Cloning, expression, and characterization of the human eosinophil eotaxin receptor. 864 44

We examined the relation between glomerular expression of chemokines from alpha-subfamily (macrophage inflammatory protein-2, MIP-2) and beta-subfamily (monocyte chemoattractant protein-1, MCP-1) and infiltration of neutrophils and monocytes in antibody mediated glomerulonephritis in rats. In the accelerated model of nephrotoxic nephritis (NTN), glomerular expression of MIP-2 and MCP-1 genes correlated with the sequential migration of neutrophil and monocyte influx, respectively. These relationships were investigated further in the heterologous phase of NTN by applying various treatments known to modulate the severity of injury. Pretreatment with bacterial lipopolysaccharide resulted in greater injury, MIP-2 expression increased 25- to 50-fold, and the glomerular neutrophil count increased two- to fourfold. Both MIP-2 mRNA levels and neutrophil infiltration were reduced by additional pretreatment with IL-6, IL-1 receptor antagonist, soluble IL-1 receptor or soluble TNF receptor (Spearman correlation coefficient r = 0.897, P < 0.005). In the heterologous phase of NTN, different pre-treatments only resulted in trivial changes in MCP-1 expression and monocyte infiltration. In conclusion, glomerular MIP-2 gene expression correlates with neutrophil infiltration both temporally during the evolution of nephritis, and when glomerular injury is modified by treatment. Glomerular MCP-1 gene expression correlates with monocyte influx. The data show chemokines of alpha- and beta-subfamilies co-operative to cause selective and sequential migration of different leukocyte subsets during development of antibody mediated glomerulonephritis.
 ...
PMID:Differential expression of macrophage inflammatory protein-2 and monocyte chemoattractant protein-1 in experimental glomerulonephritis. 864 12

Macrophage-stimulating protein (MSP), originally identified as an inducer of murine resident macrophage responsiveness to chemoattractants, is a ligand for human RON/murine STK receptor protein tyrosine kinases. Since STK was cloned from populations enriched for hematopoietic stem cells, we initiated studies on the effects of MSP on colony formation by granulocyte-macrophage (CFU-GM), erythroid (BFU-E), and multipotential (CFU-GEMM) myeloid progenitor cells. MSP alone had no colony stimulating activity. However, MSP caused about a 50% suppression of CFU-GM colony formation induced by synergistic combinations of SLF or Flt-L plus GM-CSF, G-CSF, or IL-3 and of BFU-E and CFU-GEMM colonies induced by SLF or Flt3-L plus Epo or Epo and IL-3. In contrast, MSP had no effect on progenitors stimulated by one growth factor. MSP also suppressed colony formation by stimulated cord blood progenitors, but only after preinduction to a rapidly cycling state. It was previously reported that several members of the chemokine family synergistically suppress myeloid progenitor proliferation. Likewise, synergistic suppression was observed when MSP was paired with VEGF, MIP-1 alpha, IL-8, PF4, MCP-1, IP-10, or ENA-78, or when VEGF was paired with the chemokines; and the required MSP concentration was more than 100-fold less than for MSP alone. Additionally, MSP or VEGF inhibited proliferation of the human myeloid growth factor-dependent cell line, M07e, but a sustained effect required multiple additions over time. At the least, some of the MSP suppressive effects on myeloid progenitors, as assessed on single isolated CD34 marrow cells, appeared to be directly on the progenitors; sustained additions of MSP were required to see this effect. The suppressive action of MSP and its synergism with proteins of the chemokine family may be of relevance to regulation of blood cell production.
 ...
PMID:Macrophage-stimulating protein, a ligand for the RON receptor protein tyrosine kinase, suppresses myeloid progenitor cell proliferation and synergizes with vascular endothelial cell growth factor and members of the chemokine family. 869 17

Intratracheal instillation of endotoxin (LPS) causes acute pulmonary inflammation characterized by the accumulation of plasma proteins and leukocytes within the pulmonary airways. The synthetic glucocorticoid dexamethasone 1) inhibits the LPS-initiated vascular leak of plasma proteins into the airspace, 2) inhibits the LPS-initiated emigration of neutrophils and lymphocytes into the airspace in a dose-dependent fashion, and 3) inhibits LPS-initiated mRNA and/or bronchoalveolar lavage protein expression of cytokines (TNF, IL-1 and IL-6) and chemokines (MIP-1 alpha, MIP-2 and MCP-1). In conclusion, dexamethasone inhibits both the vascular and cellular aspects of acute inflammation by downregulation of a broad spectrum of inflammatory cytokines and chemokines.
 ...
PMID:The intratracheal administration of endotoxin: X. Dexamethasone downregulates neutrophil emigration and cytokine expression in vivo. 872 19

Several studies have shown that CC chemokines attract T lymphocytes, and that CD45RO+, memory phenotype cells are considered to be the main responders. The results, however, have often been contradictory and the role of lymphocyte activation and proliferation has remained unclear. Using CD45RO+ blood lymphocytes cultured under different stimulatory conditions, we have now studied chemotaxis as well as chemokine receptor expression. Expression of the RANTES/MIP-1 alpha receptor (CC-CKR1) and the MCP-1 receptor (CC-CKR2) was highly correlated with migration toward RANTES, MCP-1, and other CC chemokines, and was strictly dependent on the presence of IL-2 in the culture medium. Migration and receptor expression were rapidly downregulated when IL-2 was withdrawn, but were fully restored when IL-2 was added again. The effect of IL-2 could be partially mimicked by IL-4, IL-10, or IL-12, but not by IL-13, IFN gamma, IL-1 beta, TNF-alpha, or by exposure to anti-CD3, anti-CD28 or phytohemagglutinin. Activation of fully responsive lymphocytes through the TCR/CD3 complex and CD28 antigen actually had the opposite effect. It rapidly downregulated receptor expression and consequent migration even in the presence of IL-2. In contrast to the effects on CC chemokine receptors, stimulation of CD45RO+ T lymphocytes with IL-2 neither induced the expression of the CXC chemokine receptors, IL8-R1 and IL8-R2, nor chemotaxis to IL-8. The prominent role of IL-2 in CC chemokine responsiveness of lymphocytes suggests that IL-2-mediated expansion is a prerequisite for the recruitment of antigen-activated T cells into sites of immune and inflammatory reactions.
 ...
PMID:Interleukin-2 regulates CC chemokine receptor expression and chemotactic responsiveness in T lymphocytes. 876 Jul 84

Once thought as immunologically naive, cells from the central nervous system have been shown to become immunologically reactive and produce various substances including cytokines and adhesion molecules. Recent investigations have revealed that mRNAs of certain cytokines such as tumor necrosis factor, interleukin-1, and interleukin-6 are expressed in the ischemic brain of the animals. Chemokines including CINC, MCP-1, and MIP-1, as well as adhesion molecules such as ICAM-1. ELAM and P-selectin were also found to be expressed. Although identification of the cells producing these cytokines were often difficult, neurons, endothelia, activated astrocytes and microglia/macrophages were the likely sources. The induction of these molecules in ischemic brain is time-locked and appears to be controlled in a highly regulated manner during the process of ischemic cascade. The functional role, interrelationship, and basic mechanism of action of these molecules are being increasingly recognized, while trials such as antiadhesion antibody molecules, growth factors, and anticytokine antibodies have been successful in reducing the neuronal damage in animals subjected to ischemic injury. Furthermore, changes of certain cytokines or adhesion molecules have been detected in the serum or cerebrospinal fluid of patients with stroke and related diseases suggesting that these molecules play a role in the pathogenesis of human stroke. Understanding of these cytokine-adhesion molecule cascades in the ischemic brain may allow us to develop new strategies for the treatment of stroke.
 ...
PMID:Cytokines and adhesion molecules in stroke and related diseases. 878 58

Following the intracranial injection of lipopolysaccharide or during acute neuronal degeneration, there is a paucity of polymorphonuclear leukocyte recruitment to the brain parenchyma and a delay in monocyte recruitment. The present study investigates whether the injection of specific leukocyte chemoattractants into the murine central nervous system can override this intrinsic resistance. Recombinant alpha-(IL-8/NAP-1 MIP-2, IP-10) and beta-chemokines (MCP-1, RANTES) were injected into the murine hippocampus and leukocyte recruitment was assessed histologically. Injections were also made into the dermis of the hind flank for comparison. At doses of 1 microgram, MCP-1 was found to be the most potent monocyte chemoattractant in the brain parenchyma and skin with IP-10 and RANTES producing minimal monocyte recruitment to both sites. In contrast IL-8, and MIP-2 provoked dramatic polymorphonuclear leukocyte recruitment in both the central nervous system and skin. The polymorphonuclear leukocyte recruitment was associated with a breaching of the blood brain barrier that was particularly severe after MIP-2. Both L-8 and MIP-2 induced blood brain barrier breakdown could be attenuated by prior depletion of the circulating leukocytes. The regulation of polymorphonuclear leukocyte chemoattractants in the brain parenchyma during injury and infection is an important area for future studies.
 ...
PMID:Overriding the brain's intrinsic resistance to leukocyte recruitment with intraparenchymal injections of recombinant chemokines. 884 93

Previous studies demonstrated the involvement of astrocytes in the development of astrogliosis, a condition in which these cells undergo proliferation and hypertrophy. To examine whether astrocytes could migrate into lesions, we tested the influence of the murine chemokines MCP-1, KC, TCA3, and MIP-1 beta on migration of cultured neonatal mouse astrocytes. Subnanomolar concentrations of MCP-1 and KC were active chemoattractants indicating that these molecules were effective at physiologic concentrations. Specificity of MCP-1 was demonstrated by antibody inhibition and by the finding that the chemokine MIP-1 beta failed to induce astrocyte migration. The migratory responses were sensitive to pertussis toxin; this finding is consistent with involvement of G protein-coupled receptors. To examine the receptors for these chemokines further, we cloned the mouse homolog of the human MCP-1 receptor from a mouse peritoneal exudate cell cDNA library. The gene had 78% nucleotide sequence homology with the human MCP-1 receptor (the nucleotide sequence of clone 1 encoding the mouse MCP-1 receptor can be obtained from the GenBank database, accession number U56819). However, reverse transcriptase-polymerase chain reaction (RT-PCR) failed to detect message for either the MCP-1 or KC receptors in astrocytes. The combined data suggest that mouse astrocytes use novel receptors to recognize these chemokines.
 ...
PMID:Mouse astrocytes respond to the chemokines MCP-1 and KC, but reverse transcriptase-polymerase chain reaction does not detect mRNA for the KC or new MCP-1 receptor. 887 98

Breast feeding improves the health of children. The greatest significance is to host defense, prevention of autoimmunity, and development of the digestive system; however, the underlying mechanisms for these effects are not well understood. Based on recent evidence that cytokines might be important in these processes, we have used ELISA to quantitate the cytokines in human colostrum, transitional, and mature milk from mothers delivering preterm or at term. We also used reverse transcription PCR to test breast milk cells for the production of cytokine mRNA. No significant (< 10 pg/ml) GM-CSF, SCF, LIF, MIP-1 alpha, IL-2, IL-4, IL-11, IL-12, IL-13, IL-15, sIL-2R, or IFN-gamma was detected. And, in contrast to earlier studies using bioassays or RIA, no significant IL-1 beta, TNF-alpha, or IL-6 was present; nor was IL-10, which had been tested using less specific antibodies. We did confirm the presence of high levels of M-CSF, which remained high throughout lactation. Human milk contained latent, but not free, TGF-beta 1, and especially TGF-beta 2, both of which may be activated by gastric acid pH. High levels of IL-1RA were detected, and like activated TGF-beta, may protect against autoimmunity. Chemokines, particularly GRO-alpha and MCP-1, but also RANTES and IL-8, were present and could protect against infection. Maternal cells in breast milk expressed mRNA for MCP-1 (20/20), IL-8 (14/20), TGF-beta 1 (14/16), TGF-beta 2 (4/6), M-CSF (9/12), IL-6 (6/12) and IL-1 beta (7/12), and may be a source of these cytokines. mRNA for IL-2, IL-10, IFN-gamma, TNF-alpha was not detected and only weak expression was found for RANTES (1/18). There was considerable variability between individual women, and women delivering preterm had lower levels of several cytokines in colostrum than women delivering at term. Yet, cytokine levels remained high months to years into lactation, providing immunological benefit to the breastfed infant/child.
 ...
PMID:Cytokines in human milk. 889 39


<< Previous 1 2 3 4 5 6 7 8 9 10 Next >>