Morphological and metastatic murine melanoma variants: motility, adhesiveness, cell surface and in vivo properties

AbstractAll capillary endothelia, including those of the glomeruli, have a luminal cell surface layer (ESL) consisting of glycoproteins, glycolipids, proteoglycans (PGs) and glycosaminoglycans. Previous results have demonstrated that an intact ESL is necessary for a normal filtration barrier and damage to the ESL coupled to proteinuria is seen for example in diabetic kidney disease (DKD). We used the principles of ion exchange chromatography in vivo to elute the highly negatively charged components of the ESL with a 1 M NaCl solution in rats. Ultrastructural morphology and renal function were analyzed and 17 PGs and hyaluronan were identified in the ESL. The high salt solution reduced the glomerular ESL thickness, led to albuminuria and reduced GFR. To assess the relevance of ESL in renal disease the expression of PGs in glomeruli from DKD patients in a next generation sequencing cohort was investigated. We found that seven of the homologues of the PGs identified in the ESL from rats were differently regulated in patients with DKD compared to healthy subjects. The results show that proteoglycans and glycosaminoglycans are essential components of the ESL, maintaining the permselective properties of the glomerular barrier and thus preventing proteinuria.

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Impact of β2 integrin deficiency on mouse natural killer cell development and function

Blood ◽

10.1182/blood-2010-10-315457 ◽

2011 ◽

Vol 117 (10) ◽

pp. 2874-2882 ◽

Cited By ~ 18

Author(s):

Karine Crozat ◽

Céline Eidenschenk ◽

Baptiste N. Jaeger ◽

Philippe Krebs ◽

Sophie Guia ◽

...

Keyword(s):

Cell Surface ◽

Nk Cells ◽

Natural Killer ◽

Nk Cell ◽

Surface Expression ◽

Cell Maturation ◽

Cell Surface Expression ◽

Mcmv Infection ◽

Β2 Integrin

Abstract Natural killer (NK) cells are innate immune cells that express members of the leukocyte β2 integrin family in humans and mice. These CD11/CD18 heterodimers play critical roles in leukocyte trafficking, immune synapse formation, and costimulation. The cell-surface expression of one of these integrins, CD11b/CD18, is also recognized as a major marker of mouse NK-cell maturation, but its function on NK cells has been largely ignored. Using N-ethyl-N-nitrosourea (ENU) mutagenesis, we generated a mouse carrying an A → T transverse mutation in the Itgb2 gene, resulting in a mutation that prevented the cell-surface expression of CD18 and its associated CD11a, CD11b, and CD11c proteins. We show that β2 integrin–deficient NK cells have a hyporesponsive phenotype in vitro, and present an alteration of their in vivo developmental program characterized by a selective accumulation of c-kit+ cells. NK-cell missing-self recognition was partially altered in vivo, whereas the early immune response to mouse cytomegalovirus (MCMV) infection occurred normally in CD18-deficient mice. Therefore, β2 integrins are required for optimal NK-cell maturation, but this deficiency is partial and can be bypassed during MCMV infection, highlighting the robustness of antiviral protective responses.

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Factors Controlling Electropermeabilisation of Cell Membranes

Technology in Cancer Research & Treatment ◽

10.1177/153303460200100502 ◽

2002 ◽

Vol 1 (5) ◽

pp. 319-327 ◽

Cited By ~ 8

Author(s):

M. P. Rols ◽

M. Golzio ◽

B. Gabriel ◽

J. Teissié

Keyword(s):

Cell Surface ◽

Electric Field ◽

Pulse Duration ◽

Cell Membranes ◽

Physical Parameters ◽

Local Exchange ◽

Physical Mechanisms ◽

A Cell

Electric field pulses are a new approach for drug and gene delivery for cancer therapy. They induce a localized structural alteration of cell membranes. The associated physical mechanisms are well explained and can be safely controlled. A position dependent modulation of the membrane potential difference is induced when an electric field is applied to a cell. Electric field pulses with an overcritical intensity evoke a local membrane alteration. A free exchange of hydrophilic low molecular weight molecules takes place across the membrane. A leakage of cytosolic metabolites and a loading of polar drugs into the cytoplasm are obtained. The fraction of the cell surface which is competent for exchange is a function of the field intensity. The level of local exchange is strongly controlled by the pulse duration and the number of successive pulses. The permeabilised state is long lived. Its lifetime is under the control of the cumulated pulse duration. Cell viability can be preserved. Gene transfer is obtained but its mechanism is not a free diffusion. Plasmids are electrophoretically accumulated against the permeabilised cell surface and form aggregates due to the field effect. After the pulses, several steps follow: translocation to the cytoplasm, traffic to the nucleus and expression. Molecular structural and metabolic changes in cells remain mostly poorly understood. Nevertheless, while most studies were established on cells in culture ( in vitro), recent experiments show that similar effects are obtained on tissue ( in vivo). Transfer remains controlled by the physical parameters of the electrical treatment.

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Endocytic Delivery of Vancomycin Mediated by a Synthetic Cell Surface Receptor: Rescue of Bacterially Infected Mammalian Cells and Tissue Targeting In Vivo

Journal of the American Chemical Society ◽

10.1021/ja067674f ◽

2007 ◽

Vol 129 (2) ◽

pp. 268-269 ◽

Cited By ~ 30

Author(s):

Siwarutt Boonyarattanakalin ◽

Jianfang Hu ◽

Sheryl A. Dykstra-Rummel ◽

Avery August ◽

Blake R. Peterson

Keyword(s):

Cell Surface ◽

Mammalian Cells ◽

Cell Surface Receptor ◽

Synthetic Cell ◽

Tissue Targeting ◽

Surface Receptor

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Substance P Increases Cell-Surface Expression of CD74 (Receptor for Macrophage Migration Inhibitory Factor): In Vivo Biotinylation of Urothelial Cell-Surface Proteins

Mediators of Inflammation ◽

10.1155/2009/535348 ◽

2009 ◽

Vol 2009 ◽

pp. 1-8 ◽

Cited By ~ 3

Author(s):

Katherine L. Meyer-Siegler ◽

Shen-Ling Xia ◽

Pedro L. Vera

Keyword(s):

Substance P ◽

Cell Surface ◽

Migration Inhibitory Factor ◽

Macrophage Migration Inhibitory Factor ◽

Urothelial Cell ◽

Inhibitory Factor ◽

Cell Surface Expression ◽

Macrophage Migration ◽

Urothelial Cells

Macrophage migration inhibitory factor (MIF), an inflammatory cytokine, and its receptor CD74 are upregulated by bladder inflammation. MIF-mediated signal transduction involves binding to cell-surface CD74, this study documents, in vivo, MIF-CD74interactions at the urothelial cell surface. N-hydroxysulfosuccinimide biotin ester-labeled surface urothelial proteins in rats treated either with saline or substance P (SP, 40 μg/kg). The bladder was examined by histology and confocal microscopy. Biotinylated proteins were purified by avidin agarose, immunoprecipitated with anti-MIF or anti-CD74 antibodies, and detected with strepavidin-HRP. Only superficial urothelial cells were biotinylated. These cells contained a biotinylated MIF/CD74 cell-surface complex that was increased in SP-treated animals. SP treatment increased MIF and CD74 mRNA in urothelial cells. Our data indicate that intraluminal MIF, released from urothelial cells as a consequence of SP treatment, interacts with urothelial cell-surface CD74. These results document that our previously described MIF-CD74 interaction occurs at the urothelial cell surface.

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Vaccinia Virus Envelope H3L Protein Binds to Cell Surface Heparan Sulfate and Is Important for Intracellular Mature Virion Morphogenesis and Virus Infection In Vitro and In Vivo

Journal of Virology ◽

10.1128/jvi.74.7.3353-3365.2000 ◽

2000 ◽

Vol 74 (7) ◽

pp. 3353-3365 ◽

Cited By ~ 183

Author(s):

Chi-Long Lin ◽

Che-Sheng Chung ◽

Hans G. Heine ◽

Wen Chang

Keyword(s):

Cell Surface ◽

Vaccinia Virus ◽

Heparan Sulfate ◽

Mutant Virus ◽

Wild Type Virus ◽

Type Virus ◽

Wild Type ◽

Virion Morphogenesis

ABSTRACT An immunodominant antigen, p35, is expressed on the envelope of intracellular mature virions (IMV) of vaccinia virus. p35 is encoded by the viral late gene H3L, but its role in the virus life cycle is not known. This report demonstrates that soluble H3L protein binds to heparan sulfate on the cell surface and competes with the binding of vaccinia virus, indicating a role for H3L protein in IMV adsorption to mammalian cells. A mutant virus defective in expression of H3L (H3L−) was constructed; the mutant virus has a small plaque phenotype and 10-fold lower IMV and extracellular enveloped virion titers than the wild-type virus. Virion morphogenesis is severely blocked and intermediate viral structures such as viral factories and crescents accumulate in cells infected with the H3L− mutant virus. IMV from the H3L− mutant virus are somewhat altered and less infectious than wild-type virions. However, cells infected by the mutant virus form multinucleated syncytia after low pH treatment, suggesting that H3L protein is not required for cell fusion. Mice inoculated intranasally with wild-type virus show high mortality and severe weight loss, whereas mice infected with H3L− mutant virus survive and recover faster, indicating that inactivation of the H3L gene attenuates virus virulence in vivo. In summary, these data indicate that H3L protein mediates vaccinia virus adsorption to cell surface heparan sulfate and is important for vaccinia virus infection in vitro and in vivo. In addition, H3L protein plays a role in virion assembly.

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Constitutive and Regulated Shedding of Soluble FGF Receptors Releases Biologically Active Inhibitors of FGF-2

International Journal of Molecular Sciences ◽

10.3390/ijms22052712 ◽

2021 ◽

Vol 22 (5) ◽

pp. 2712

Author(s):

Anne Hanneken ◽

Maluz Mercado ◽

Pamela Maher

Keyword(s):

Cell Surface ◽

Ligand Binding ◽

Cellular Proliferation ◽

Biological Activities ◽

Biological Properties ◽

Matrix Metalloproteases ◽

Biologically Active ◽

Ectodomain Shedding ◽

High Affinity

The identification of soluble fibroblast growth factor (FGF) receptors in blood and the extracellular matrix has led to the prediction that these proteins modulate the diverse biological activities of the FGF family of ligands in vivo. A recent structural characterization of the soluble FGF receptors revealed that they are primarily generated by proteolytic cleavage of the FGFR-1 ectodomain. Efforts to examine their biological properties are now focused on understanding the functional consequences of FGFR-1 ectodomain shedding and how the shedding event is regulated. We have purified an FGFR-1 ectodomain that is constitutively cleaved from the full-length FGFR-1(IIIc) receptor and released into conditioned media. This shed receptor binds FGF-2; inhibits FGF-2-induced cellular proliferation; and competes with high affinity, cell surface FGF receptors for ligand binding. FGFR-1 ectodomain shedding downregulates the number of high affinity receptors from the cell surface. The shedding mechanism is regulated by ligand binding and by activators of PKC, and the two signaling pathways appear to be independent of each other. Deletions and substitutions at the proposed cleavage site of FGFR-1 do not prevent ectodomain shedding. Broad spectrum inhibitors of matrix metalloproteases decrease FGFR-1 ectodomain shedding, suggesting that the enzyme responsible for constitutive, ligand-activated, and protein kinase C-activated shedding is a matrix metalloprotease. In summary, shedding of the FGFR-1 ectodomain is a highly regulated event, sharing many features with a common system that governs the release of diverse membrane proteins from the cell surface. Most importantly, the FGFR ectodomains are biologically active after shedding and are capable of functioning as inhibitors of FGF-2.

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Surface charge distribution on the endothelial cell of liver sinusoids.

The Journal of Cell Biology ◽

10.1083/jcb.99.2.639 ◽

1984 ◽

Vol 99 (2) ◽

pp. 639-647 ◽

Cited By ~ 30

Author(s):

L Ghitescu ◽

A Fixman

Keyword(s):

Endothelial Cell ◽

Cell Surface ◽

Liver Sinusoid ◽

Electron Microscopic ◽

Coated Pits ◽

Endothelial Cell Surface ◽

Liver Sinusoids ◽

Surface Charge Distribution ◽

Cationic Residues

The topography of the charged residues on the endothelial cell surface of liver sinusoid capillaries was investigated by using electron microscopic tracers of different size and charge. The tracers used were native ferritin (pl 4.2-4.7) and its cationized (pl 8.4) and anionized (pl 3.7) derivatives, BSA coupled to colloidal gold (pl of the complex 5.1), hemeundecapeptide (pl 4.85), and alcian blue (pl greater than 10). The tracers were either injected in vivo or perfused in situ through the portal vein of the mouse liver. In some experiments, two tracers of opposite charge were sequentially perfused with extensive washing in between. The liver was processed for electron microscopy and the binding pattern of the injected markers was recorded. The electrostatic nature of the tracer binding was assessed by perfusion with high ionic strength solutions, by aldehyde quenching of the plasma membrane basic residues, and by substituting the cell surface acidic moieties with positively charged groups. Results indicate that the endothelial cells of the liver sinusoids expose on their surface both cationic and anionic residues. The density distribution of these charged groups on the cell surface is different. While the negative charge is randomly and patchily scattered all over the membrane, the cationic residues seem to be accumulated in coated pits. The charged groups co-exist in the same coated pit and bind the opposite charged macromolecule. It appears that the fixed positive and negative charges of the coated pit glycocalyx are mainly segregated in space. The layer of basic residues is located at 20-30-nm distance of the membrane, while most of the negative charges lie close to the external leaflet of the plasmalemma.

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Regulation of c-met expression in B16 murine melanoma cells by melanocyte stimulating hormone

Journal of Cell Science ◽

10.1242/jcs.112.5.623 ◽

1999 ◽

Vol 112 (5) ◽

pp. 623-630

Author(s):

D. Rusciano ◽

P. Lorenzoni ◽

M.M. Burger

Keyword(s):

Melanoma Cells ◽

Parental Cell ◽

Melanocortin Receptor ◽

Parental Cell Line ◽

Melanocyte Stimulating Hormone ◽

Murine Melanoma ◽

The One ◽

Murine Melanoma Cells ◽

Stimulating Hormone

B16 murine melanoma cells selected in vivo for enhanced liver metastatic ability (B16-LS9) show on the one hand an increased expression and constitutive activation of the proto-oncogene c-met (the receptor for hepatocyte growth factor/scatter factor), and on the other hand a more differentiated phenotype, when compared to the parental cell line, B16-F1. Following this observation, we have tried to establish whether there is a direct relationship between differentiation and c-met expression in B16 melanoma cells. Treatment of these cells with differentiating agents indicated that c-met expression was strongly induced by melanocyte stimulating hormone, while retinoic acid had almost no influence. c-met induction was triggered by engagement of the melanocortin receptor, cAMP elevation and PKA/PKC(α) activation, as respectively shown by the effects of ACTH, cAMP elevating agents and specific PK inhibitors. Regulation of c-met expression via the melanocortin receptor and cAMP raises the intriguing possibility that autocrine and/or paracrine mechanisms acting in vivo on this circuit might influence (through c-met expression and activation) the metastatic behavior of these tumor cells, which we have shown to be dependent on their c-met expression.

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