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)

Adhesion of hematopoietic cells to extracellular matrix components is important for blood cell development. However, little is known regarding the potential influence of IL-3 on this process for precursor B cells and Flt3-ligand has not yet been implicated in induction of adhesion of any blood cell types to extracellular matrix components. Therefore, we examined the characteristics of cytokine-induced cell adhesion to fibronectin (FN), using as a model the murine precursor B cell line, Baf3, a factor-dependent cell line requiring IL-3 for both growth and survival. Since factor-dependent hematopoietic cell lines expressing Flt3 receptor are extremely rare, we also studied Baf3/Flt3, a subline of Baf3 transduced with the Flt3 receptor gene. IL-3 induced adhesion of Baf3 and Baf3/Flt3 cells to FN, while Flt3-ligand induced adhesion of Baf3/Flt3 cells only. Whereas both Baf3 and Baf3/Flt3 cells expressed VLA-4 and -5 integrins as FN receptors, expression levels of VLA-4 and -5 were not affected by IL-3 or Flt3-ligand treatment. However, blocking experiments using anti-integrin antibodies showed that cytokine-induced adhesion of cells depended on both VLA-4 and -5 suggesting that IL-3 and Flt3-ligand activated these integrins. PI-3 kinase inhibitor wortmannin, PKC inhibitor H-7, or PKA inhibitor HA1004 did not suppress adhesion induced by IL-3 or Flt3-ligand; in contrast, PLC inhibitor U-73122 did suppress adhesion, suggesting the possibility that PLC, but not PI-3 kinase, PKC, or PKA, may be involved in this process. Since it is known that IL-3 and Flt3-ligand receptors are expressed on precursor B cells, and these receptors are downregulated during B cell maturation of primary cells, the induction of precursor B cell adhesion to FN by IL-3 and Flt3-ligand may contribute a mechanism by which precursor B cells adhere to bone marrow stroma, thereby influencing their development.
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PMID:Interleukin-3 and Flt3-ligand induce adhesion of Baf3/Flt3 precursor B-lymphoid cells to fibronectin via activation of VLA-4 and VLA-5. 968

Adhesion is required for cell growth, differentiation, survival, and function. Cell adhesion is mediated by a structurally diverse group of plasma membrane receptors, each exhibiting specialized ligand-binding properties that are needed for specific tasks. Integrin-mediated adhesion is important for hematopoietic stem (HSC)/progenitor (HPC) cell survival and may prevent programmed cell death. Interleukin (IL)-11, a multi-functional cytokine secreted by the bone marrow environment, plays an important role in regulating growth and differentiation of HSCs/HPCs. In this report, we demonstrate that IL-11 enhanced adhesion of freshly isolated and 3 day-expanded CD34+ cells to immobilized fibronectin. the expression of very late antigen (VLA)-4 and VLA-5 integrins was detected on CD34+ cells. CD34+ cells also expressed a-chain and gp130 subunits of the IL-11 receptor (R). Enhanced adhesion by IL-11 was mediated via activation of VLA-5 integrins, since this action could be blocked by monoclonal antibodies against beta 1 and alpha 5, but not alpha 4, integrins. Addition of phosphatidylinositol (PI)-3 kinase inhibitors blocked IL-11 enhanced adhesion of CD34+ cells to fibronectin. The results suggest that this enhanced adhesion is associated with the PI-3 kinase pathway, an inside-out signaling pathway.
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PMID:Interleukin-11 enhancement of VLA-5 mediated adhesion of CD34+ cells from cord blood to fibronectin is associated with the PI-3 kinase pathway. 1083 6

Thrombin activates mast cells to release inflammatory mediators through a mechanism involving protease-activated receptor-1 (PAR-1). We hypothesized that PAR-1 activation would induce mast cell adhesion to fibronectin (FN). Fluorescent adhesion assay was performed in 96-well plates coated with FN (20 microg/ml). Murine bone marrow cultured mast cells (BMCMC) were used after 3-5 wk of culture (>98% mast cells by flow cytometry for c-Kit expression). Thrombin induced beta-hexosaminidase, IL-6, and matrix metalloproteinase-9 release from BMCMC. Thrombin and the PAR-1-activating peptide AparafluoroFRCyclohexylACitY-NH(2) (cit) induced BMCMC adhesion to FN in a dose-dependent fashion, while the PAR-1-inactive peptide FSLLRY-NH(2) had no effect. Thrombin and cit induced also BMCMC adhesion to laminin. Thrombin-mediated adhesion to FN was inhibited by anti-alpha(5) integrin Ab (51.1 +/- 6.7%; n = 5). The combination of anti-alpha(5) and anti-alpha(4) Abs induced higher inhibition (65.7 +/- 7.1%; n = 5). Unlike what is known for FcepsilonRI-mediated adhesion, PAR-1-mediated adhesion to FN did not increase mediator release. We then explored the signaling pathways involved in PAR-1-mediated mast cell adhesion. Thrombin and cit induced p44/42 and p38 phosphorylation. Pertussis toxin inhibited PAR-1-mediated BMCMC adhesion by 57.3 +/- 7.3% (n = 4), indicating that G(i) proteins are involved. Wortmannin and calphostin almost completely inhibited PAR-1-mediated mast cell adhesion, indicating that PI-3 kinase and protein kinase C are involved. Adhesion was partially inhibited by the mitogen-activated protein kinase kinase 1/2 inhibitor U0126 (24.5 +/- 3.3%; n = 3) and the p38 inhibitor SB203580 (25.1 +/- 10.4%; n = 3). The two inhibitors had additive effects. Therefore, thrombin mediates mast cell adhesion through the activation of G(i) proteins, phosphoinositol 3-kinase, protein kinase C, and mitogen-activated protein kinase pathways.
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PMID:Thrombin induces mast cell adhesion to fibronectin: evidence for involvement of protease-activated receptor-1. 1237 Mar 92

Adhesion to extracellular matrix plays important roles in the regulation of survival, proliferation, differentiation and homing of hematopoietic cells and is regulated by a wide variety of growth factors, adhesion receptors and other ligands that mediate the cell to matrix and cell to cell interaction. Stem cell factor (SCF) plays important roles in the regulating growth and self-renewal of hematopoietic stem/progenitor cells. In the report, the effects of stem cell factor on the adhesion of hematopoietic cells to fibronectin were observed by using a hematopoietic growth factor dependent cell line-Mo7e. Results showed that Mo7e cells express the very late antigen VLA-4 (beta1 alpha4) and VLA-5 (beta1 alpha5) integrins. The expression of the SCF receptor (c-kit) was also detected in the Mo7e cells. SCF enhances the adhesion of Mo7e cells to fibronectin in a concentration dependent manner. SCF enhanced adhesion of Mo7e cells to fibronectin was blocked by anti-beta1, alpha4 and alpha5 antibodies. Addition of PI-3 kinase inhibitors also blocked the adhesion of Mo7e cells to fibronectin induced by SCF. It was concluded that SCF enhances the adhesion of Mo7e cells to fibronectin, and this process is mediated by integrins and PI-3 kinase pathway.
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PMID:[Stem cell factor enhances the adhesion of hematopoietic cells to fibronectin]. 1251 5