Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P15088 (mast cell)
 14,925 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Integrins are multifunctional recognition molecules and are expressed on various hematopoietic cells. In the present study expression of integrins on the cell surface of human mast cells and human basophils was investigated by using monoclonal antibodies (mAbs) and indirect immunofluorescence. Human mast cells were obtained from lung (n = 5), uterus (n = 5) and skin (n = 4). Human blood basophils were obtained from normal donors (n = 2). In addition, HMC-1 cells (human mast cell line) and KU-812 cells (a basophil cell line) were analyzed. Primary mast cells were found to react with mAbs directed against the common beta chain of beta 1 integrins (CD 29), the alpha chain of VLA-4 (CD 49 d) and VLA-5 (CD 49 e), the beta chain of beta 3 integrins (CD 61), and the alpha chain of the vitronectin receptor (VNR) (CD 51). Mast cells were not recognized by mAbs to beta 2 integrins (CD 18, CD 11 a, CD 11 b, CD 11 c), the alpha chain of VLA-2 (CD 49 b), and VLA-6 (CD 49 f). No differences in expression of integrins on human mast cells obtained from different organs were found. HMC-1 cells and primary mast cells expressed an almost identical pattern of integrins. Human basophils and KU-812 cells were found to react with mAbs directed against beta 1-integrins (CD 29, CD 49 b, CD 49 d, CD 49 e) and beta 2-integrins (CD 18, CD 11 a, CD 11 b, CD 11 c). Together, mast cells and blood basophils express a unique pattern of integrins. These cell surface structures may be involved in the distribution of basophils and tissue mast cells and their accumulation and function in inflammed tissues.
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PMID:Differential expression of cell surface integrins on human mast cells and human basophils. 164 54

We have evaluated the adhesion of human cutaneous mast cells to several components of the extracellular matrix (plasma fibronectin, laminin, collagen type I and IV) and studied whether these cells express the beta 1 integrins potentially involved in the adhesion to these proteins. Human skin mast cells (5.1 +/- 1.5% pure) spontaneously adhered to fibronectin and laminin (0.1 to 10 micrograms/ml) immobilized on plastic surfaces (e.g., 14 +/- 7.2% and 14 +/- 4.4% adhesion at 10 micrograms/ml, respectively). Similar results were obtained with a 90% pure mast cell preparation. In contrast, cutaneous mast cells did not adhere to collagen type I (1.6 +/- 0.5% adhesion) or type IV (1.2 +/- 0.8% adhesion). Control adhesion in BSA-coated wells was < 5%. Mast cell adhesion to fibronectin was optimal after an incubation period of 60 to 90 min (t1/2 = 28.2 +/- 6.2 min), whereas adhesion to laminin was faster (t1/2 = 10.1 +/- 1.2 min), being nearly optimal after a 15-min incubation period. Human skin mast cell adhesion to fibronectin and laminin was found to be dependent on the presence of divalent cations in the extracellular medium. Dual-color immunofluorescence and flow cytometry were used to evaluate whether human skin mast cells (51.3 +/- 3.9% pure) express beta 1 integrins that may mediate cell adhesion to extracellular matrix proteins. These mast cells were found to express VLA (very late Ag)-3 (75.3 +/- 35.6 specific fluorescence intensity) and, to lesser degree, VLA-4 and VLA-5 receptors (8.0 +/- 2.5 and 6.9 +/- 3.2 specific fluorescence intensity, respectively). In contrast, VLA-1, VLA-2, and VLA-6 integrins were not expressed significantly. mAb to VLA-3, VLA-4, and VLA-5 each inhibited by 70% skin mast cell adhesion to fibronectin. mAb to VLA-3 nearly abolished mast cells adhesion to laminin, whereas anti-VLA-4 and anti-VLA-5 were ineffective. Finally, immunosuppressant cyclosporin A (100 nM) and FK-506 (10 nM) significantly inhibited mast cell adhesion to both fibronectin and laminin (p < 0.05). Our data demonstrate that human skin mast cells spontaneously adhere to fibronectin and laminin, and that this adhesion is mediated by VLA-3, VLA-4, and/or VLA-5 integrins on these cells. Interactions between these beta 1 integrins and extracellular matrix proteins may be involved in perivascular tissue localization of human mast cells in vivo.
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PMID:Human skin mast cells express functional beta 1 integrins that mediate adhesion to extracellular matrix proteins. 753 41

The development of mast cells from bone marrow precursors and their function as the mucosal- or connective-tissue-type mast cell are critically dependent on microenvironmental factors. Extracellular matrix proteins, such as collagen, fibronectin, and laminin, may represent insoluble components of the microenvironment. Recent studies have described multiple isoforms of laminin isolated from different tissues. In the present study, adhesion of mouse bone marrow-derived mast cells (BMMC) and long-term mast cell lines to Engelbreth-Holm-Swarm (EHS) tumor laminin, rat laminin, human merosin, and human placental laminin was compared. The greatest level of adhesion was found with human laminin as the substrate. By use of a newly prepared mouse VLA-alpha 6 integrin-specific mAb (MA6) together with the previously described mAb GoH3, VLA-6 (alpha 6 beta 1) integrin was found to be expressed and utilized by BMMC and long-term mast cell lines. VLA-6 has been described as a major laminin receptor with roles in diverse cell functions including cell growth and differentiation. BMMC have been shown to express a 32/67-kDa laminin receptor. Therefore, in addition to the 32/67-kDa laminin receptor described in early studies, BMMC also express VLA-6 integrin, which may have roles in the regulation of their development.
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PMID:Integrin VLA-6 (alpha 6 beta 1) mediates adhesion of mouse bone marrow-derived mast cells to laminin. 889 18

Mast cell numbers are increased significantly in oral lichen planus (OLP). In other inflammatory conditions, mast cells frequently adhere to extracellular matrix proteins such as laminin. The aim of this study, therefore, was to determine whether the distribution of mast cells in OLP is related topographically to laminin in vascular and epithelial basement membranes. Monoclonal antibodies for tryptase, laminin and the alpha6beta1 CD49f laminin-binding integrin were used to identify mast cells, basement membranes (blood vessels and basal epithelium) and the "classical" laminin adhesion receptor, respectively. A double-labelling immunoperoxidase technique was employed to examine and compare mast cell-laminin relationships in OLP (n=19) and normal buccal mucosa (NBM, n=13). In both OLP and NBM, the majority of mast cells were located close to vascular basement membranes. Quantitative studies revealed that the number of mast cells associated with the laminin of vascular basement membranes (distance <1 microm) was two-fold and three-fold higher, respectively, in the superficial and deep layers in OLP compared with NBM (P<0.001). The frequency distribution of mast cells associated with basal epithelium was not statistically different in both groups (P>0.05). The association of mast cells with laminin may be an important determinant of mast cell density in OLP During OLP lesion formation and progression, the preferential distribution of mast cells in the immediate perivascular region provides an ideal situation for mast cell-derived mediators to influence the vascular endothelium.
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PMID:Associations between mast cells and laminin in oral lichen planus. 956 71

Integrins are expressed on mast cells and constitute an essential prerequisite for the accumulation of the cells at sites of inflammation. In order to clarify a potential contribution of inflammatory cytokines to this process, we have studied the modulation of integrin expression and adhesion of immature human mast cells (HMC-1) to extracellular matrix proteins by interleukin-6, tumor necrosis factor alpha, interferon-alpha and interferon-gamma. Corticosteroids were used for comparison. On fluorescence-activated cell sorter analysis, preincubation of cells for 48 h with different concentrations of interleukin-6 induced a significant, up to 40%, increase of alpha v alpha 5, CD49b (alpha 2), CD49e (alpha 5), CD49f (alpha 6), and CD51 (alpha v). In contrast, different concentrations of tumor necrosis factor alpha, interferon-alpha, interferon-gamma, and dexamethasone (10-8-10-10 M) inhibited expression of adhesion receptors by up to 60%, reaching significance for some but not all integrins. On semiquantitative polymerase chain reaction analysis, interleukin-6, the other cytokines, and corticosteroids significantly modulated expression of alpha1, alpha v and alpha 5 integrin chains at mRNA level. Functional significance of these findings was proven in adhesion assays using fibronectin, laminin, and vitronectin, with interleukin-6 causing significant enhancement of adhesion in all cases, tumor necrosis factor alpha and dexamethasone inducing significant reduction of adhesion to fibronectin and laminin, and interferon-gamma significantly inhibiting adhesion to fibronectin only. Specificity of interleukin-6-induced changes was demonstrated using antibodies against alpha1 and alpha 5 integrins in unstimulated and interleukin-6-prestimulated cells. These data show that interleukin-6 stimulates mast cell adhesion to extracellular matrix and thus allows for the accumulation of the cells at tissue sites by enhancing integrin expression, whereas tumor necrosis factor alpha, interferon-alpha, interferon-gamma, and dexamethasone downmodulate this process.
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PMID:Interleukin-6 enhances whereas tumor necrosis factor alpha and interferons inhibit integrin expression and adhesion of human mast cells to extracellular matrix proteins. 1271 84