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Query: UMLS:C0001511 (
Adhesion
)
5,955
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
There is evidence that mature megakaryocytes migrate into sinusoids, enter the blood and fragment in the vascular bed. We wondered whether differences in expression of adhesion antigens could be associated with the egress of megakaryocytes from bone marrow into the peripheral blood or the fragmentation into platelets. Megakaryocytes from human marrow were purified by counterflow centrifugal elutriation followed by a glycoprotein Ib-dependent agglutination procedure. Megakaryocytes from central venous blood and pulmonary arteries were purified by counterflow centrifugal elutriation alone.
Adhesion
antigens were labelled in an immunohistochemical assay. Both bone marrow megakaryocytes and platelets from healthy volunteers stained > 75% positive for
CD36
, CD41, CD42, Cdw49b (alpha subunit VLA2), Cdw49e (alpha subunit VLA5), Cdw49f (alpha subunit VLA6) and CD62. Circulating megakaryocytes, although > 75% positive for CD41, had, unlike platelets and bone marrow megakaryocytes, a reduced and remarkable heterogeneous (5-100% positive) labelling with antibodies against Cdw49b, Cdw49e, Cdw49f. These results could be confirmed by comparing the bone marrow megakaryocytes, circulating megakaryocytes and platelets from 7 patients that were recovered and processed at the same time. Morphologically mature, circulating megakaryocytes have, unlike bone marrow megakaryocytes, a heterogeneous expression of adhesion antigens, especially of Cdw49b, Cdw49e, and Cdw49f.
...
PMID:Expression of adhesion antigens of human bone marrow megakaryocytes, circulating megakaryocytes and blood platelets. 144 25
The
CD36
and ICAM-1 glycoproteins on vascular endothelial cells have been implicated as cytoadherence receptors for Plasmodium falciparum-infected erythrocytes (IRBC).
Adhesion
of IRBC from Thai patients with uncomplicated and severe falciparum malaria to purified
CD36
or ICAM-1 and to C32 melanoma cells was compared. All malaria isolates bound to solid phase-adsorbed
CD36
and to fluid-phase 125I-labeled
CD36
. IRBC adhesion to purified ICAM-1 varied widely, and no correlation with clinical severity of disease was observed. The cytoadherent phenotype of IRBC was modulated by selective panning on plates coated with purified
CD36
or ICAM-1. IRBC selected by panning on CD36+, ICAM-1+ melanoma cells bound to cells that express surface
CD36
but not to
CD36
-deficient cells, indicating that
CD36
exerts a strong selective pressure on the IRBC cytoadherent phenotype. IRBC adhesion to
CD36
and ICAM-1 suggests that P. falciparum parasites may use these receptors in vivo to promote parasite survival and immune evasion.
...
PMID:Molecular basis of sequestration in severe and uncomplicated Plasmodium falciparum malaria: differential adhesion of infected erythrocytes to CD36 and ICAM-1. 171 52
Adhesion
of parasitized red blood cells (RBCs) to vascular endothelium is thought to be a key factor in the pathology of falciparum malaria. However, quantitative analyses of the intercellular forces and of the effects of flow on adhesion have been lacking. We have characterized cytoadhesion of RBCs parasitized by the strains ITO4 (which can bind to receptors ICAM-1 or
CD36
) and FCR3A2 (which can bind to
CD36
only) using micropipette manipulation and flow chamber techniques. Target cells were unfixed or glutaraldehyde-fixed human umbilical vein endothelial cells (HUVEC, bearing ICAM-1 only) or human amelanotic melanoma cells (C32, bearing
CD36
and ICAM-1). In the static, micropipette assay, 60% to 70% of parasitized cells would adhere when tested at up to three successive sites. The percentage of cells adhering and the force required for their detachment (approximately 10(-10) N) were similar for each combination of parasite strain and adhesion target (ITO4/HUVEC, ITO4/C32, FCR3A2/C32). In the flow chamber, efficiency of initial adhesion of parasitized cells was essentially constant (at about 1%) up to a stress of 0.1 Pa, and then decreased rapidly with increasing stress. Either receptor (ICAM-1 or
CD36
) could immobilize flowing cells at a physiologic flow stress (0.1 Pa), but the numbers of cells adhering varied for the different combinations (ITO4/C32 greater than ITO4/HUVEC greater than FCR3A2/C32). When flow was increased in steps, adhered cells were gradually washed off but many could withstand stresses at which they would not initially adhere. The force for detachment estimated in this way was similar to the pipette value, and again, was similar for the different combinations of strains and targets.
Adhesion
from flow depends on the affinity between surfaces being above a critical level, and once adhesion is established, the fracture energy determines resistance to disruption of adhesion. The results show that the fracture energy is greater than the affinity (ie, that adhesion becomes stabilized after it is initially established) and that the ratio of affinity to fracture energy is different for different receptor/ligand pairs, with ICAM-1 appearing to be the more efficient immobilizing receptor. Also, static and flow-based assays of adhesion clearly differ; the affinity is less critical in the static situation, so that most parasitized cells were capable of adhering in a static assay, but fewer did so under flow. Adhesiveness varied markedly from cell to cell, both for targets and parasitized cells.(ABSTRACT TRUNCATED AT 400 WORDS)
...
PMID:Rheological analysis of the adhesive interactions of red blood cells parasitized by Plasmodium falciparum. 173 18
Adhesion
of parasitized erythrocytes to microvascular endothelium is a central event in the pathogenesis of severe falciparum malaria. We have characterized the adhesion of flowing parasitized red blood cells to three of the known endothelial receptors coated on plastic surfaces (
CD36
, intercellular adhesion molecule-1 (ICAM-1) and thrombospondin (TSP)), and also to cells bearing these receptors (human umbilical vein endothelial cells (HUVEC) and platelets). All of the surfaces could mediate adhesion at wall shear stress within the physiological range. The great majority of adherent parasitized cells formed rolling rather than static attachments to HUVEC and ICAM-1, whereas static attachments predominated for platelets,
CD36
and TSP. Studies with monoclonal antibodies verified that binding the HUVEC was mainly via ICAM-1, and to platelets via
CD36
.
Adhesion
via ICAM-1 was least sensitive to increasing wall shear stress, but absolute efficiency of adhesion was greatest for
CD36
, followed by ICAM-1, and least for TSP. TSP did not give long-lasting adhesion under flow, whereas cells remained adherent to
CD36
or ICAM-1. We propose that the different receptors may have complementary roles in modulating adhesion in microvessels. Initial interaction at high wall shear stress may be of a rolling type, mediated by ICAM-1 or other receptors, with immobilization and stabilization occurring via
CD36
and/or TSP.
...
PMID:Rolling and stationary cytoadhesion of red blood cells parasitized by Plasmodium falciparum: separate roles for ICAM-1, CD36 and thrombospondin. 752 15
Adhesion
of parasitized red blood cells to vascular endothelium contributes to the ischaemic pathology of severe falciparum malaria. One of the endothelial cytoadhesion receptors,
CD36
, is also expressed by platelets. We have studied adhesion of flowing parasitized cells to a surface coated with immobilized, activated platelets, both as a model for
CD36
-mediated adhesion and because interaction with platelets might play a direct role in thrombotic complications of malaria. Parasitized cells were able to bind firmly to platelets over a range of shear stress (up to 0.3 Pa) close to those found in the microcirculation. The binding was largely abolished by treatment of platelets with antibody to
CD36
, with only a small effect by antibody to ICAM-1. Binding showed pH sensitivity consistent with previous reports of
CD36
-mediated cytoadhesion. Fixation of the platelet surface with formaldehyde preserved adhesion and its antibody sensitivity, while fixation with glutaraldehyde greatly reduced adhesion and increased the sensitivity to antibody against ICAM-1. Thus
CD36
-mediated binding is inhibited by glutaraldehyde--but not formaldehyde--fixation, while ICAM-1 can mediate adhesion after either form of fixation. We conclude that platelet-coated surfaces (with or without fixation) represent a practically simple model for studying malarial cytoadhesion and that platelets are likely to be able to bind parasitized cells in vivo and could thus promote vascular occlusion.
...
PMID:Plasmodium falciparum: characterization of adhesion of flowing parasitized red blood cells to platelets. 752 16
Microvascular endothelial cells (EC) recruit circulating leukocytes at sites of inflammation, in part through cytokine-regulated expression of endothelial-leukocyte adhesion molecules.
Adhesion
molecule expression varies among vascular beds and among EC within microvessels of a particular vascular bed. In the present study, we have examined the patterns of antigen expression and cytokine responsiveness of dermal microvascular endothelial cells (DMEC) in a skin organ culture model and, for comparison, in cell culture. Within the superficial vascular plexus (SVP) of normal skin, CD36 molecule expression is undetectable on capillary loops and is expressed on DMEC in only 20% of the larger, horizontal vessels.
CD36
expression is not modulated by cytokines. Endothelial-leukocyte adhesion molecule-1 (ELAM-1) expression induced at 6 and 24 h by TNF or IL-1, is restricted to the venular side of the capillary loop and to the venules proper. Vascular cell adhesion molecule-1 (VCAM-1) expression is not inducible on EC of the SVP in normal skin by TNF, IL-1, or IL-4, alone or in combination at either time point. When inflamed skin is examined in organ culture, SVP EC are cytokine responsive regarding VCAM-1 expression. Within the deep vascular plexus (DVP).
CD36
molecules are expressed on EC in all capillaries and small vessels. Both ELAM-1 and, to a lesser extent, VCAM-1 expression are inducible by TNF, IL-1, and/or IL-4 on capillaries and larger microvessels at 6 and 24 h. The larger vessels at the dermal-subcutaneous border were found to be
CD36
-/ELAM-1+/VCAM-1+ after cytokine treatment.
CD36
expression of DMEC in cell culture varies from 47 to 98% of cells (mean 75%) in seven separate isolates and is not modified by cytokines. Upon TNF or IL-1 activation, 50 to 90% of DMEC express ELAM-1 molecules at 6 h and expression persists at high levels for 24 h. VCAM-1 expression is negligible at both times. These results with DMEC differ from human umbilical vein EC analyzed in parallel, which are completely
CD36
- and show transient ELAM-1 and sustained VCAM-1 expression in response to TNF and IL-1. In summary, we have demonstrated that DMEC comprise a heterogeneous population that differ from umbilical vein EC.
...
PMID:Heterogeneity of dermal microvascular endothelial cell antigen expression and cytokine responsiveness in situ and in cell culture. 769 64
To determine virulence factors of isolates of Plasmodium falciparum and the potential role of cytokines in cerebral malaria, 46 Malagasy patients presenting with cerebral (n = 10), severe (n = 10), and uncomplicated (n = 26) malaria were enrolled in a study. The capacity of 21 of 46 P. falciparum isolates to form rosettes in vitro and to adhere to human umbilical vein endothelial cells (HUVECs) that express intercellular adhesion molecule-1 receptors and to C32 amelanotic melanoma cells that express mainly
CD36
receptors was investigated together with the effects of tumor necrosis factor alpha (TNF-alpha), granulocyte macrophage-colony-stimulating factor (GM-CSF), interleukin-3 (IL-3), and IL-6 alone and in two-by-two combinations on the cytoadherence of infected erythrocytes to HUVECs. Plasma levels of these cytokines were also measured in the patients at admission. The percentage of rosette formation was higher for the isolates from patients with cerebral (n = 6; 19.5%) and severe (n = 6; 30.5%) malaria than for those from patients with uncomplicated malaria (n = 9; 5%) (P < 0.002). The cytoadherence properties of the isolates did not differ among the three groups whatever the target cell used, but adherence to melanoma cells was systematically higher than that to HUVECs.
Adhesion
to HUVECs was increased more after TNF-alpha stimulation than after GM-CSF, IL-3, or IL-6 stimulation (P < 0.01). Only the combination of TNF-alpha and IL-3 enhanced cytoadherence more than TNF-alpha used alone (P < 0.02). No difference in the modulation of cytoadherence by cytokines was found in relation to the severity of the disease. TNF-alpha and IL-6 levels in peripheral blood were higher in the patients with cerebral and severe malaria than in the patients with uncomplicated malaria (P < 0.005). Most of the patients' sera contained little or no IL-3 or GM-CSF. Our results challenge the role of intercellular adhesion molecule-1 as the principal receptor mediating the cytoadherence of P. falciparum-infected erythrocytes and contrast with data obtained in the murine model.
...
PMID:Parasite virulence factors during falciparum malaria: rosetting, cytoadherence, and modulation of cytoadherence by cytokines. 822 94
HPMECs were successfully isolated by differential trypsinization from peripheral lung lobes. The cells proliferated rapidly in EGM-MV with 10% FBS and were serially cultivated for more than 20 passages (1:4 split ratio) in vitro. Cells were characterized as endothelial based upon their cobblestone morphology, the presence of factor VIII-related antigen, incorporation of DiI-Ac-LDL, tubule-like structure formation in Matrigel, and positive staining for ACE.
Adhesion
molecules were tested at passage 3 and passage 12. Cells demonstrated intense staining for PECAM-1 both unstimulated and stimulated with TNF-alpha (20 ng/ml). The adhesion molecules ICAM-1, VCAM-1, ELAM-1, and P-selectin differed in expression on unstimulated cells. ICAM-1 was constitutively expressed on unstimulated cells and the expression was increased by TNF-alpha stimulation (20 hr). In contrast, VCAM-1, ELAM-1, and P-selectin were not detected on unstimulated cells but were detected after stimulation with TNF-alpha. The inducibility of adhesion molecules was different. VCAM-1 (10 hr) and ELAM-1 (4 hr) were expressed more strongly than P-selectin (minutes to 4 hr). The adhesion molecule profile found on passage 12 was the same as on passage 3.
CD36
was not detected on both unstimulated and stimulated (4 and 8 hr) cells. The peak of adhesion of HL-60 cells to TNF-alpha activated HPMEC monolayers was around 8 hr. The results indicate that HPMEC can be continuously grown in vitro for many passages without losing their adhesion molecule expression. This expression of adhesion molecules confirms that HPMECs might be a good in vitro model in the understanding of various aspects of pulmonary microvascular endothelial cell function and may be useful as the basis for studies of adhesion molecule targeted therapies of pulmonary inflammatory diseases.
...
PMID:Expression of adhesion molecules in cultured human pulmonary microvascular endothelial cells. 858 50
Plasmodium falciparum gametocyte-infected erythrocytes are characterized by their ability to sequester in the microvasculature of various organs, primarily the spleen and bone marrow. This phenomenon is thought to play a critical role in the development and survival of the sexual stages. Little is known, however, about ligands on the gametocyte-infected erythrocyte. Infection of erythrocytes with mature asexual stages of P. falciparum (trophozoites and schizonts) has been shown to induce modification of the erythrocyte anion transporter, band 3, and this has been linked to the acquisition of an adherent phenotype. Here, we demonstrate for the first time that immature gametocyte-infected erythrocytes also express modified band 3. In vitro binding assays demonstrate that gametocyte-infected erythrocytes of the 3D7 strain utilize this surface receptor for adhesion to C32 amelanotic melanoma cells via the host cell receptor
CD36
(platelet glycoprotein IIIb).
Adhesion
of gametocyte-infected erythrocytes to
CD36
-transfected CHO cells is also dependent on modified band 3. However, modified band 3 does not mediate adhesion of gametocyte-infected erythrocytes to intercellular adhesion molecule 1, a second host receptor for gametocytes expressed on C32 cells.
...
PMID:Plasmodium falciparum gametocyte adhesion to C32 cells via CD36 is inhibited by antibodies to modified band 3. 892 98
Adhesion
molecules on the endothelial surface of the blood-brain barrier (BBB) play an important role in the pathogenesis of many encephalopathies, including multiple sclerosis (MS) and cerebral malaria (CM). The expression of four surface molecules of relevance to MS and CM on the immortalized human umbilical vein endothelial cell line, ECV304, was investigated using immunofluorescence flow cytometry. We found that ECV304 cells express intercellular adhesion molecule-1 (ICAM-1) and low levels of
CD36
, but not vascular cell adhesion molecule-1 (VCAM-1) or E-selectin. This expression pattern was unaltered on ECV304 cells which were co-cultured with C6 glioma cells; conditions under which the endothelial cells display enhanced barrier formation. Tumour necrosis factor-alpha (TNF-alpha), which is elevated in MS and CM, decreased the integrity of the barrier in co-cultured endothelial cells and upregulated the expression of ICAM-1 nine-fold. The significance of elevated ICAM-1 expression in relation to the binding of parasitised erythrocytes at the BBB in CM is discussed.
...
PMID:Upregulation of intercellular adhesion molecule-1 expression on human endothelial cells by tumour necrosis factor-alpha in an in vitro model of the blood-brain barrier. 1036 90
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