The assembly and activation of kinin-forming systems on the surface of human U-937 macrophage-like cells

2009 ◽  
Vol 390 (3) ◽  
Author(s):  
Anna Barbasz ◽  
Andrzej Kozik
Keyword(s):  
Cell Surface ◽  
Binding Sites ◽  
Plasma Proteins ◽  
Factor Xii ◽  
Tissue Kallikrein ◽  
Bulk Fluid ◽  
Cell Line Model ◽  
Inflammatory State ◽  
Generating System ◽  
Plasma Kinin

AbstractA complex of three plasma proteins, including the high molecular mass kininogen (HK), prekallikrein (PK), and factor XII (FXII), is known to assemble on cell surfaces to release bradykinin-related proinflammatory peptides (kinins). Only recently, the binding of HK to human macrophages was described in the U-937 cell line model. In the present study, the adsorption of the other components of plasma kinin-generating system to these cells was characterized. FXII was found to tightly bind to U-937 cells and was also shown to partially compete with HK for the same binding sites on the macrophage surface. The Mac-1 and gC1qR proteins were found to be receptors for FXII on the cell surface. PK indirectly docked to the macrophages via the cell-bound HK and FXII. Within the complex of these proteins assembled on the macrophage, PK could be activated by FXII/FXIIa or independently of this factor, and the active PK effectively released kinins from HK. The cell surface-bound HK could also be the substrate for tissue kallikrein approaching the cell from the bulk fluid. The kinins released at the surface are suggested to induce secondary responses in the macrophages, leading to further propagation of the inflammatory state.

scholarly journals Assembly of contact-phase factors on the surface of the human neutrophil membrane

Blood ◽  
1994 ◽  
Vol 84 (2) ◽  
pp. 474-482 ◽  
Author(s):  
LM Henderson ◽  
CD Figueroa ◽  
W Muller-Esterl ◽  
KD Bhoola
Keyword(s):  
Binding Sites ◽  
Human Neutrophil ◽  
External Surface ◽  
Human Neutrophils ◽  
Phase System ◽  
Factor Xii ◽  
Tissue Kallikrein ◽  
The Novel ◽  
Contact Phase ◽  
Neutrophil Cell

H-kininogen (HK), a major factor involved in contact-phase activation, was recently immunolocalized on the external surface of human neutrophils. Experiments were, therefore, designed to consider the question of whether the complete assembly of contact factors occurs on the outer surface of the neutrophil membrane. By immunolocalization techniques, and using specific antibodies directed against the various contact factors, we now demonstrate that plasma prekallikrein (PK), factor XI (FXI), and factor XII (FXII) are present on the exterior face of the human neutrophil. Failure to localize HK, PK, or FXI by monoclonal antibodies directed to their reciprocal binding sites, and displacement of PK/FXI by peptide HK31, which mimics the relevant binding site(s) of HK, suggested that prekallikrein and FXI are anchored to the neutrophil membrane through attachment to the kininogen molecule. Probing of the kinin moiety by a specific antibody showed that kininogen molecules bound to the neutrophil cell membrane contain the kinin sequence, which can be released by plasma kallikrein or by tissue kallikrein. Our results led us to the novel conclusion that neutrophils provide a circulating platform for the components of the contact-phase system.

scholarly journals Assembly of contact-phase factors on the surface of the human neutrophil membrane

Blood ◽  
1994 ◽  
Vol 84 (2) ◽  
pp. 474-482 ◽  
Author(s):  
LM Henderson ◽  
CD Figueroa ◽  
W Muller-Esterl ◽  
KD Bhoola
Keyword(s):  
Binding Sites ◽  
Human Neutrophil ◽  
External Surface ◽  
Human Neutrophils ◽  
Phase System ◽  
Factor Xii ◽  
Tissue Kallikrein ◽  
The Novel ◽  
Contact Phase ◽  
Neutrophil Cell

Abstract H-kininogen (HK), a major factor involved in contact-phase activation, was recently immunolocalized on the external surface of human neutrophils. Experiments were, therefore, designed to consider the question of whether the complete assembly of contact factors occurs on the outer surface of the neutrophil membrane. By immunolocalization techniques, and using specific antibodies directed against the various contact factors, we now demonstrate that plasma prekallikrein (PK), factor XI (FXI), and factor XII (FXII) are present on the exterior face of the human neutrophil. Failure to localize HK, PK, or FXI by monoclonal antibodies directed to their reciprocal binding sites, and displacement of PK/FXI by peptide HK31, which mimics the relevant binding site(s) of HK, suggested that prekallikrein and FXI are anchored to the neutrophil membrane through attachment to the kininogen molecule. Probing of the kinin moiety by a specific antibody showed that kininogen molecules bound to the neutrophil cell membrane contain the kinin sequence, which can be released by plasma kallikrein or by tissue kallikrein. Our results led us to the novel conclusion that neutrophils provide a circulating platform for the components of the contact-phase system.

scholarly journals Cell surface-binding sites for progesterone mediate calcium uptake in human sperm.

1991 ◽  
Vol 266 (28) ◽  
pp. 18655-18659 ◽  
Author(s):  
P.F. Blackmore ◽  
J. Neulen ◽  
F. Lattanzio ◽  
S.J. Beebe
Keyword(s):  
Cell Surface ◽  
Binding Sites ◽  
Calcium Uptake ◽  
Human Sperm ◽  
Surface Binding ◽  
Cell Surface Binding

Target cell surface glycoconjugates and neural induction in an amphibian

Development ◽  
1985 ◽  
Vol 86 (1) ◽  
pp. 39-51
Author(s):  
Lydie Gualandris ◽  
Pierre Rouge ◽  
Anne-Marie Duprat
Keyword(s):  
Cell Surface ◽  
Binding Sites ◽  
Neural Induction ◽  
Specific Receptor ◽  
Con A ◽  
Neural Signal ◽  
Electrophysiological Properties ◽  
Ionic Fluxes ◽  
Target Membrane ◽  
Cell Surface Glycoconjugates

The possible involvement of target membrane specific receptor(s) in the transmission of the neural signal leading to activation of the intracellular machinery involved in the process of neural determination, has been examined using lectin probes (Con A, succinylated-ConA, LcA, PsA and SBA). Not only Con A binding sites but many different glycoconjugated molecules (α-Dgalactose, N-acetyl-D-galactosamine, α-D-fucose, N-acetyl-D-glucosamine, etc.) would have to be involved, if neural receptor(s) are invoked to explain initiation of neural induction. We show here that the close involvement of such receptor molecules in neural induction is so far hypothetical and remains to be demonstrated. Moreover we are inclined to the view of Barth and others who suggested that ionic fluxes and physicochemical and electrophysiological properties of the target membrane could play a crucial role in neural induction.

Chemotaxis-associated properties of separated prestalk and prespore cells of Dictyostelium discoideum

1986 ◽  
Vol 64 (8) ◽  
pp. 722-732 ◽  
Author(s):  
J. D. Mee ◽  
D. M. Tortolo ◽  
M. B. Coukell
Keyword(s):  
Light Scattering ◽  
Cell Surface ◽  
Dictyostelium Discoideum ◽  
Binding Sites ◽  
Large Fraction ◽  
Cell Types ◽  
The Other ◽  
Deficient Mutant ◽  
Camp Phosphodiesterase ◽  
Intracellular Cgmp

During development, prestalk and prespore cells of Dictyostelium discoideum become organized in multicellular structures. This physical association makes it difficult to characterize the two cell types biochemically and physiologically. In the present study, we have separated prestalk and prespore cells from 16-h slugs by the method of Tsang and Bradbury and have examined a number of chemotaxis-associated properties of these cells. When assayed on phosphate-buffered agar under both gradient and nongradient conditions, isolated prestalk cells responded chemotactically to cAMP and, unexpectedly, to folate and certain folate derivatives. In contrast, separated prespore cells failed to respond appreciably to any of these compounds. Neither prestalk nor prespore cells of strain HC91 exhibited a cAMP-induced increase in intracellular cGMP. However, a cGMP response was observed in both prestalk and prespore cells of strain NP368, a cGMP phosphodiesterase deficient mutant. Both cell types exhibited comparable cAMP-mediated light-scattering changes and possessed similar levels of surface cAMP- and folate-binding sites. On the other hand, prestalk cells had at least fourfold higher cAMP phosphodiesterase and folate deaminase activities than prespore cells, and a large fraction of both activities was on the cell surface. Therefore, the greater chemotactic response of prestalk cells to cAMP and folate on agar might be due, in part, to their increased capacity to generate a chemoattractant gradient. Results obtained in this study demonstrate that prestalk and prespore cells separated by this procedure can be used in certain physiological as well as biochemical experiments.

scholarly journals Conformational epitopes at cadherin calcium-binding sites and p120-catenin phosphorylation regulate cell adhesion

2012 ◽  
Vol 23 (11) ◽  
pp. 2092-2108 ◽  
Author(s):  
Yuliya I. Petrova ◽  
MarthaJoy M. Spano ◽  
Barry M. Gumbiner
Keyword(s):  
Cell Surface ◽  
Conformational Changes ◽  
Binding Sites ◽  
Calcium Binding ◽  
Cell Types ◽  
P120 Catenin ◽  
Physiological Regulation ◽  
Conformational Epitopes ◽  
Calcium Binding Sites ◽  
E Cadherin

We investigated changes in cadherin structure at the cell surface that regulate its adhesive activity. Colo 205 cells are nonadhesive cells with a full but inactive complement of E-cadherin–catenin complexes at the cell surface, but they can be triggered to adhere and form monolayers. We were able to distinguish the inactive and active states of E-cadherin at the cell surface by using a special set of monoclonal antibodies (mAbs). Another set of mAbs binds E-cadherin and strongly activates adhesion. In other epithelial cell types these activating mAbs inhibit growth factor–induced down-regulation of adhesion and epithelial morphogenesis, indicating that these phenomena are also controlled by E-cadherin activity at the cell surface. Both types of mAbs recognize conformational epitopes at different interfaces between extracellular cadherin repeat domains (ECs), especially near calcium-binding sites. Activation also induces p120-catenin dephosphorylation, as well as changes in the cadherin cytoplasmic domain. Moreover, phospho-site mutations indicate that dephosphorylation of specific Ser/Thr residues in the N-terminal domain of p120-catenin mediate adhesion activation. Thus physiological regulation of the adhesive state of E-cadherin involves physical and/or conformational changes in the EC interface regions of the ectodomain at the cell surface that are mediated by catenin-associated changes across the membrane.

Participation of concanavalin A binding sites in the interaction between Trypanosoma cruzi and macrophages

1983 ◽  
Vol 62 (1) ◽  
pp. 287-299
Author(s):  
M.N. Meirelles ◽  
A. Martinez-Palomo ◽  
T. Souto-Padron ◽  
W. De Souza
Keyword(s):  
Plasma Membrane ◽  
Cell Surface ◽  
Trypanosoma Cruzi ◽  
Uniform Distribution ◽  
Concanavalin A ◽  
Binding Sites ◽  
Peritoneal Macrophages ◽  
Untreated Mouse ◽  
Mouse Peritoneal Macrophages

Untreated mouse peritoneal macrophages as well as macrophages treated with concanavalin A (ConA) were incubated in the presence of untreated or ConA-treated epimastigotes and trypomastigotes of Trypanosoma cruzi. Treatment of epimastigotes or trypomastigotes with ConA increased or decreased their uptake by macrophages, respectively. Treatment of their macrophages with ConA reduced by 70% and increased by five times the ingestion of epimastigotes and trypomastigotes, respectively. These results are discussed in relation to previous studies on the mobility of ConA receptors in the membrane of the parasite. Using fluorescein- or ferritin-labelled ConA we observed that ConA binding sites located on the plasma membrane of macrophages are internalized during endocytosis of T. cruzi, and observed in association with the membrane of the endocytic vacuole. Vacuoles without parasites showed a uniform distribution of ConA binding sites, while these sites were distributed in patches in vacuoles containing parasites. These results, in association with others previously reported, suggest the involvement of glycoproteins and/or glycolipids localized on the cell surface of T. cruzi and macrophages during the T. cruzi-macrophage interaction.

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