Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Both macrophages (MAC) and dendritic cells (DC) are members of the mononuclear phagocyte system (MPS) with monocytes (MO) as common precursor cells. Cells of the MPS are able to take up, process and present antigens to T lymphocytes, thereby inducing a primary or secondary immune response. Adhesion molecules are of crucial importance for the interaction of antigen-presenting cells with immune cells, especially T lymphocytes. By representational difference analysis, we identified CD49c (VLA-3), a member of the beta1-integrin family of adhesion receptors, as differentiation-associated antigen in MO-derived MAC. In contrast, MO-derived DC did not express CD49c mRNA. These data prompted us to compare the integrin expression pattern of MAC and DC. Both cell types showed a low expression of the alpha-chains of the beta1-integrins CD49a, CD49b, CD49d and CD49e, whereas a marked difference was observed for CD49c and CD49f. Expression of both integrins increased during MO to MAC differentiation, but was not detectable on DC. In parallel the beta1-chain (CD29) was clearly up-regulated during MO to MAC differentiation but was only weakly expressed on DC. On the other hand, the beta2-integrins CD11a, CD11b, CD11c and CD18 were all expressed on MAC and DC. Beside their role in cell-cell interaction and adhesion, beta2-integrins are also known as possible binding molecules for bacteria and lipopolysaccharide (LPS), especially for high LPS concentrations. Therefore we investigated the LPS response of MAC versus DC in terms of tumour necrosis factor-alpha (TNF-alpha) release. DC were less responsive to low doses of LPS, which can easily be explained by the very low CD14 expression on DC compared for MAC. In contrast, the TNF-alpha response was comparable to MAC when DC were stimulated with high LPS concentrations. Our results show a specific, differentiation-dependent pattern of beta1- and beta2-integrin expression on in vitro-generated MAC and DC. We suggest that the high expression of CD11/CD18 on DC could be involved in the LPS binding of DC. As LPS is not only an activation but also a differentiation stimulus for DC, the expression of CD11/CD18 on DC may be important for the successful maturation of DC and thereby the initiation of a primary immune response.
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PMID:Comparative analysis of integrin expression on monocyte-derived macrophages and monocyte-derived dendritic cells. 1092 59

Exposure of Brown Norway rats to mercuric chloride induces systemic autoimmunity, involving T- and B-lymphocyte activation, (auto-)antibody production and multiorgan inflammation. Several divalent metal ions, such as Mg2+ and Mn2+, can activate binding of integrins to their ligands, thus causing lymphocyte adhesion. To test the hypothesis that Hg2+ acts in a similar way, we studied the effect of HgCl2 on integrin-mediated T-cell adhesion. HgCl2 induced cell-cell aggregation of human T lymphoblasts. Exposure of a human T-cell clone to HgCl2 for 1 hr enhanced, in a dose-dependent way, cell binding to fibronectin (FN) and to intercellular adhesion molecules (ICAM) -1, -2 and -3. Furthermore, HgCl2 induced strong binding of Jurkat T cells to FN. These effects of HgCl2 were of similar magnitude as the effects of phorbol 12-myristate 13-acetate (PMA) or MnCl2. Studies using blocking antibodies indicated the involvement of CD11a in binding to ICAMs, and of CD49d, CD49e, and CD29 in binding to FN. Adhesion to FN induced by HgCl2 or by PMA, but not by MnCl2, was dependent on temperature and on extracellular Ca2+ or Mg2+. Addition of cytochalasin B enhanced synergistically the FN adhesion induced by MnCl2, whereas the effects of PMA and HgCl2 were not modified. These results indicate that Hg2+ is a potent activator of T-cell adhesion, mediated by several integrins and ligands. In contrast to the effect of MnCl2, HgCl2-induced cell adhesion probably involves an intracellular pathway. Activation of integrins by HgCl2 may play an important role in activation and migration of leucocytes involved in HgCl2-induced immune dysregulation in vivo.
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PMID:The immune dysregulatory compound mercuric chloride induces integrin-mediated T-lymphocyte adhesion. 1116 34

Adhesion molecules, such as CD49d, CD50 and CD62L, have important roles in many adhesive interactions involving cells of the immune system. Since it has been shown that many immunological alterations are present in aged subjects, we studied, by means of triple colour whole blood immunostaining and multiparametric flow cytometry, the expression and intensity level (MFI) of these molecules on peripheral blood lymphocyte subpopulations from 23 healthy elderly subjects and 13 young controls. In the elderly a decrease in total peripheral blood lymphocytes bearing CD62L antigen was observed (39 +/- 13% vs 63 +/- 6% and 745 +/- 312/mm3 vs 1,393 +/- 407/mm3; p<0.001), whereas the numbers of lymphocytes expressing CD49d and CD50 antigens were comparable in aged and young subjects. In addition, CD50 and CD62L MFI values on total peripheral blood lymphocytes were higher in elderly than in young subjects (5.23 +/- 1.03 vs 4.18 +/- 0.44, p = 0.001 and 2.60 +/- 0.35 vs 2.21 +/- 0.40, p = 0.005 respectively) while the intensity expression of CD49d was unchanged. The percentages and absolute numbers of T and B lymphocytes expressing CD62L were decreased in elderly compared to young subjects (CD62L+CD3+: 43 +/- 15% vs 66 +/- 9% and 581 +/- 257/mm3 vs 1,028 +/- 418/mm3, p<0.001; CD62L+CD19+: 78 +/- 12% vs 90 +/- 4%, p < 0.005 and 103 +/- 64/mm3 vs 207 +/- 98, p < 0.001). A decrease in the proportion of CD62L bearing NK cells was also observed in the elderly (25 +/- 14% vs 46 +/- 24%, p<0.005), although their absolute number was unchanged. No significant differences were detected in the proportion of T, B and NK lymphocytes expressing CD49d and CD50 antigens and only the absolute numbers of B cells expressing these adhesion molecules were lower in elderly (CD49d+CD19+: 121 +/- 71/mm3 and CD50+CD19+: 107 +/- 73/mm3) compared to young donors (CD49d+CD19+: 248 +/- 112/mm3 and CD50+CD19+: 235 +/- 120/mm3, p < 0.001). Moreover, the intensity of adhesion molecule expression was differentially modulated in the elderly depending on the specific lymphocyte cell population considered. The densities of CD49d, CD50 and CD62L antigens on B and NK lymphocytes from the two age groups were not different; on the contrary, T lymphocytes from elderly donors exhibited increased CD49d (1.69 +/- 0.09 vs 1.62 +/- 0.07, p < 0.05), CD50 (4.98 +/- 1.16 vs 3.77 +/- 0.46, p < 0.001) and CD62L (2.26 +/- 0.38 vs 1.99 +/- 0.37, p < 0.05) MFI values compared to young donors.
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PMID:Adhesion molecules on peripheral blood lymphocyte subpopulations in the elderly. 1119 33

There is mounting evidence that alpha(4) (CD49d) integrins are involved in neutrophil recruitment and function during inflammatory responses. We report that all resting murine neutrophils derived from bone marrow or peripheral blood express easily detectable levels of alpha(4) integrins on their surface. These alpha(4) integrins were functional, as demonstrated by stimulation of respiratory burst when neutrophils adhered to surfaces coated with the murine vascular cell adhesion molecule-1 (mVCAM-1). Adhesion occurred via alpha(4) integrins, as preincubation of neutrophils with an anti-alpha(4)-specific Ab inhibited attachment to mVCAM-1. Direct cross-linking of the alpha(4) integrin subunit by surface-bound mAbs also elicited superoxide release and release of the secondary granule marker, lactoferrin. The functional responses that occurred downstream of alpha(4) integrin cross-linking required signaling by Src family kinases. Neutrophils derived from hck(-/-)fgr(-/-)lyn(-/-) triple-knockout or hck(-/-)fgr(-/-) double-knockout mice failed to undergo respiratory burst when plated on mVCAM-1. Triple mutant neutrophils were also defective in release of both superoxide and lactoferrin when plated on surfaces coated with mAbs directed against alpha(4). Correlated with impaired alpha(4)-induced functional responses, triple-mutant neutrophils also failed to spread and tightly adhere to anti-alpha(4) mAb-coated surfaces. This is the first direct evidence that functional alpha(4) integrins are expressed by murine PMNs, and that these surface molecules can mediate cellular responses such as tight adhesion, spreading, sustained respiratory burst, and specific granule release in vitro. Moreover the alpha(4) integrins, like all other integrins tested, use the Src family kinases to transduce intracellular signals.
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PMID:Resting murine neutrophils express functional alpha 4 integrins that signal through Src family kinases. 1123 61

1. The nitric oxide synthase (NOS) inhibitor, N(omega)-nitro-L-arginine methyl ester (L-NAME), inhibits both rat and human eosinophil chemotaxis in vitro. Here, the role of nitric oxide (NO) in human eosinophil cell surface integrin expression and function was investigated. 2. Human peripheral blood eosinophils were treated with L-NAME (0.01 - 1.0 mM) and their adhesion to human fibronectin and serum observed. Adhesion of cells to fibronectin and serum increased by 24.0+/-4.6 and 43.8+/-4.7%, respectively, when eosinophils were treated with 1.0 mM L-NAME. Increased adhesion by L-NAME could be abolished when cells were co-incubated with VLA-4- and Mac-1-specific monoclonal antibodies (mAbs). 3. The NO donor, sodium nitroprusside (2.5 mM), significantly inhibited eosinophil adhesion to fibronectin and serum by 34.3+/-4.5 and 45.2+/-5.6%, respectively. This inhibition was accompanied by a 4 fold increase in the levels of intracellular cyclic GMP. 4. Flow cytometrical analysis demonstrated that L-NAME induced an increased expression of CD11b (Mac-1) on the eosinophil cell surface of 36.3+/-7.4%. L-NAME had no effect upon CD49d (VLA-4) expression. 5. Treatment of human eosinophils, in vitro, with H-[1,2,4] oxadiazolo quinoxalin-1-one (ODQ) (0.1 mM), an inhibitor of soluble guanylate cyclase, also significantly increased eosinophil adhesion to fibronectin and serum by 73.5+/-17.9 and 91.7+/-12.9%, respectively. This increase in adhesion could also be inhibited by co-incubation with the Mac-1 and VLA-4-specific mAbs. 6. In conclusion, results indicate that NO, via a cyclic GMP-dependent mechanism, inhibits the adhesion of human eosinophils to the extracellular matrix (ECM). This inhibition is accompanied by a decrease in the expression and function of the eosinophil's adhesion molecules, in particular, the expression of the Mac-1 integrin and the function of the VLA-4 integrin.
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PMID:Nitric oxide regulates human eosinophil adhesion mechanisms in vitro by changing integrin expression and activity on the eosinophil cell surface. 1158 18

The study was designed to investigate the changes, both numerically and functionally, of the molecules critical to wound healing in spinal cord injury (SCI) patients. Spinal cord injury patients who demonstrated delayed healing of their pressure ulcers were used as study subjects. Age-matched healthy individuals served as controls. Adhesion molecule expression of the peripheral blood leukocytes, including lymphocytes and granulocytes, was measured by flow cytometric analysis. Binding capacity of the lymphocytes was evaluated using human umbilical cord vein endothelial cells (HUVECs) as the binding matrix. Samples from pressure ulcers of the patients were immunostained to define fibronectin, kalinin, beta4 integrin, alpha2beta1, alpha3beta1, alpha5beta1, and CD138 expression. Compared to healthy controls, there was decreased expression of CD11a, CD11b, CD18, CD49b, CD49c, CD49d, CD54, and CD8 in patients' lymphocyte populations and CD11a, CD18, CD49c, CD49d, and CD8 in patients' granulocyte populations. The binding capacity, expressed as percentage binding of the lymphocytes to the HUVEC matrix, was greatly diminished in the patients. There was markedly diminished immunohistochemical staining of fibronectin in pressure ulcers. These findings showed that delayed healing of pressure ulcers in SCI patients can be attributed to reduced adhesion molecule expression, impaired cell-cell interaction, and lack of extracellular matrix structural and functional protein.
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PMID:Cellular and molecular alterations in spinal cord injury patients with pressure ulcers: a preliminary report. 1189 Jul 21

Synergistic interactions between cytokines, chemokines and adhesion molecules may facilitate the selective recruitment of eosinophils into sites of allergic inflammation. Ovalbumin-sensitized IL5TG mice responded to antigen challenge with robust airway eosinophilia 24 and 72 hr post-exposure. Adhesion molecule expression and functional responsiveness of immune cells derived from IL5TG mice to various inflammatory mediators were evaluated. IL5TG-derived eosinophils, but not neutrophils, expressed higher levels of CD49d and CD11b relative to WT. Functional responsiveness to eotaxin was increased in IL5TG eosinophils as demonstrated by a 10x increase in its potency in producing actin polymerization and 3x increase in CD11b upregulation relative to WT. These data are consistent with increased CCR3 expression on IL5TG eosinophils. Responsiveness of eosinophils to LTB4 or MIP-1alpha was similar between WT and IL-5TG mice. These data provide evidence of synergy between eosinophil-specific cytokines and chemokines that may promote accumulation of this cell type under conditions of allergic inflammation in vivo.
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PMID:Functional effects of eotaxin are selectively upregulated on IL-5 transgenic mouse eosinophils. 1208 17

Adhesion molecules are known to be an important part of leukocyte migration and extravasation in both homeostatic and inflammatory conditions. Intracellular adhesion molecule-1 (ICAM-1 or CD54) is constitutively expressed on endothelial cells and is up-regulated during acute and chronic inflammation. We investigated the efficacy and consequences of interfering with CD54 after administration of an antisense oligonucleotide to ICAM-1 (CD54) in the transgenic HLA-B27/beta2 microglobulin rat model. One hundred percent of the HLA-B27 transgene + animals will spontaneously develop chronic inflammation (some more severely than others) in the gastric mucosa, cecum, and colon. We carried out two studies, i.p. injection and rectal administration of antisense. Following i.p. and rectal treatment, there were significant decreases in colonic mucosal wall thickness, histologic inflammation, CD54 expression in the colon and peripheral blood, and the percentage of colon weight per end body weight. Furthermore, decreased expression of CD49d, CD18, and tumor necrosis factor-alpha was observed in antisense treated rats. Therefore, the HLA-B27 transgenic model of spontaneous and chronic inflammatory bowel disease, which has increased expression of adhesion molecules, responds to both routes of administration of ICAM-1 antisense oligonucleotides. These studies support the regulatory role of adhesion molecules in chronic intestinal inflammation, the need for an understanding of how the route of drug delivery can alter the dose and area affected, and finally the role of antisense oligonucleotides as a therapeutic modality in chronic spontaneous inflammatory bowel diseases.
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PMID:Amelioration of chronic and spontaneous intestinal inflammation with an antisense oligonucleotide (ISIS 9125) to intracellular adhesion molecule-1 in the HLA-B27/beta2 microglobulin transgenic rat model. 1218 46

CCR6 is expressed by memory T cells (mTC) and is a requirement for efficient arrest of a subset of mTC to activated human dermal microvascular endothelial cells (HDMEC) under physiologic shear stress. We now address whether CCR6 alone is sufficient to induce arrest of a model T cell line (Jurkat) that shows low expression of all CCRs tested (CCR1-10). Herein, we transduced Jurkat (JK) T cells expressing fucosyltransferase VII with a chimeric chemokine receptor consisting of CCR6 fused to enhanced green fluorescent protein. In contrast to the starting JK lines, the resulting cell line (JK fucosyltransferase VII-CCR6) migrated 6-fold better to CCL20 in chemotaxis assays, arrested in response to CCL20 that was immobilized to plastic, and demonstrated a 2.5-fold increase in adhesion to activated HDMEC (p = 0.001). Adhesion was blocked by anti-CD18 mAb (p = 0.005) but not by anti-CD49d mAb (p = 0.3). After arrest on recombinant substrates, CCR6 clustered on the surface as detected by real-time observation of enhanced green fluorescent protein fluorescence. Dual-label confocal microscopy revealed that LFA-1 (CD18 and CD11a), but not CXCR4, colocalized with clustered CCR6 in the presence of immobilized CCL20. Thus, the functional expression of CCR6 is sufficient to provide the chemokine signaling necessary to induce arrest of a JK T cell line to activated HDMEC. Clustering of CCR6 and coassociation with critical integrins may serve to strengthen adhesion between T cells and activated endothelial cells.
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PMID:CCR6 colocalizes with CD18 and enhances adhesion to activated endothelial cells in CCR6-transduced Jurkat T cells. 1219

Malignant plasma cells (PC) from multiple myeloma (MM) patients characteristically home to the bone marrow (BM). High numbers of tumour cells are found in the peripheral blood (PB) only at end-stage disease (secondary plasma cell leukaemia, PCL) in a minority of patients. Using flow cytometric and fluorescence in situ hybridization (FISH) analysis, a high percentage of tumoral BM PC from untreated patients was found to express CD106. In addition, these cells also expressed an activated form of CD29, as determined using the CD29 activation reporter monoclonal antibody HUTS-21. Adhesion-binding experiments showed that CD106+-activated CD29+ BM PC from these patients adhered to fibronectin (FN) in a CD29/CD49d-dependent manner. In contrast, marrow PC from progressive patients and BM or circulating malignant cells from secondary PCL patients expressed lower levels or were negative for CD106 and activated CD29, respectively, with a decreased or zero ability to adhere to FN. The expression of constitutive CD29 and CD49d, however, was similar during disease progression. We conclude that BM myelomatous cells co-express CD106 and a functionally active form of CD29. Moreover, our results suggest that the loss of expression and/or function of these antigens are associated with the progression of MM and may explain the exit of tumoral cells from the BM.
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PMID:CD106 and activated-CD29 are expressed on myelomatous bone marrow plasma cells and their downregulation is associated with tumour progression. 1235 5


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