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Query: UMLS:C0001511 (Adhesion)
 5,955 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Adhesion molecules play a crucial part in cell-matrix and in cell-cell interactions. These interactions, which are essential to the body's defense processes, involve adhesion molecules belonging to different families: integrins, immunoglobulins and selectins. Integrins are expressed by a large number of tissues, whereas other adhesion molecule families are restricted to a small number of cell types. A recent symposium dealt with the recruitment of circulating platelets at specific sites, their adhesion to extracellular matrix components and their activation by agonists leading to aggregation or attachment to other cells. These events, supporting hemostasis and thrombosis, involve integrins, selectins and other adhesion molecules. This report focuses on newly reported integrins (GPIa, GPIc, GPIIa), selectins (GMP-140) and GPIIIb, previously known as 'minor' surface oriented platelet glycoproteins. Major membrane glycoproteins such as GPIIb-IIIa (an integrin) and GPIb, which also play a vital role in platelet functions, have been extensively reviewed elsewhere.
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PMID:New families of adhesion molecules play a vital role in platelet functions. 220 5

The purpose of this study was to determine whether a heterodimeric complex immunologically related to the fibrinogen receptor could function as a thrombospondin (TSP) receptor in TSP-mediated cell-substratum adhesion of human melanoma cells. We found that polyclonal antibodies to the platelet GPIIb-IIIa complex, GPIIIa, and the human vitronectin receptor inhibited TSP-mediated cell adhesion by 63-68%. Immunoprecipitation of detergent extracts of 125I-surface-labeled melanoma cells using either anti-human platelet GPIIb-IIIa or anti-human vitronectin receptor antibody revealed the presence of a single heterodimeric complex, suggesting that both antisera recognize the same integrin receptor, GPIIb-IIIa-like antigen. Adhesion of cells to TSP is likely mediated through a region of the TSP molecule containing the arginine-glycine-aspartic (RGD) peptide sequence, since cell attachment to TSP was inhibited 50-66% in the presence of peptides containing RGD. These results strongly suggest that a GPIIb-IIIa-like/vitronectin receptor can serve as a cell binding site for TSP in mediating cell-substratum adhesion.
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PMID:The GPIIB-IIIa-like complex may function as a human melanoma cell adhesion receptor for thrombospondin. 247 Jun 6

Adhesion of platelets to the subendothelium is an essential step in hemostasis and thrombosis. Several receptors for adhesive macromolecules have been identified on platelets and are included in the integrin family. To clarify the role of platelet membrane glycoproteins in the interaction of platelets with the subendothelium, 51Cr-labeled platelet adhesion assay and antibody-blocking experiments were performed by using in vitro cultured subendothelium under the static condition. The platelet adhesion in this assay was inhibited by anti-GPIa (VLA-2), GPIc (VLA-5) and -GPIc'-(VLA-6) antibodies, while anti-GPIb and -GPIIb/IIIa antibodies had no effect. Platelets from the patients with Glanzmann's thrombasthenia could also attach to the subendothelium, whereas those from a patient whose platelets lacked GPIa failed to attach to the extracellular matrix (ECM). The monoclonal antibodies against fibronectin and laminin which recognized the cell binding domain of these molecules inhibited the platelet adhesion when they were pre-treated with ECM. Furthermore, antibody-blocking experiments revealed that the percent inhibition by the combination of anti-GPIa, -GPIc and -GPIc' antibodies used herein was approximately 75%. They did not completely inhibit the attachment. These results suggest that the interactions of collagen, fibronectin and laminin with their receptors on platelets are involved in the mechanism of platelet adhesion to subendothelium.
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PMID:Role of membrane glycoproteins in the interaction of blood platelets with the vessel wall--the study on platelet adhesion to in vitro cultured subendothelial matrix. 262 57

Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb-IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de-endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb-IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation.
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PMID:Platelet adhesion and thrombus formation on subendothelium in platelets deficient in glycoproteins IIb-IIIa, Ib, and storage granules. 293 7

Soluble fibronectin binds specifically to glycoprotein (GP) IIb-IIIa on thrombin-activated platelets, and this binding is not observed with platelets of patients with Glanzmann's thrombasthenia (GT) which lack GPIIb-IIIa. Here we report that GT platelets retain the ability to interact with fibronectin-coated surfaces. Adhesion to fibronectin does not require platelet activation and is inhibited by soluble fibronectin, antibodies specific for fibronectin, peptides containing the sequence Arg-Gly-Asp and polyclonal antibodies specific for band 3 of the chicken embryo fibroblast fibronectin receptor (anti-band 3). Using anti-band 3, we have purified a second fibronectin receptor from human platelets, a heterodimer composed of glycoproteins previously designated GPIc and GPIIa. The GPIc-IIa complex is found on both GT and normal platelets and appears to be identical to the GP138 kD-GP160 kD complex recently immunopurified by Giancotti et al. (1986. Exp. Cell Res. 163:47-62) and by Sonnenberg et al. (1987. J. Biol. Chem. 268:10376-10383). In this report, we provide the first evidence that GPIc-IIa actually mediates adhesion of platelets to fibronectin-coated surfaces. GPIc-IIa thus represents a second functional fibronectin receptor, distinct from GPIIb-IIIa, that is largely responsible for the adhesion of nonactivated platelets to fibronectin-coated surfaces.
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PMID:Glycoprotein Ic-IIa functions as an activation-independent fibronectin receptor on human platelets. 296 81

The adhesion of human fixed washed platelets (FWP) to collagen was decreased after treatment with Serratia marcescens protease (SP), which removed 95% of the glycocalicin from platelet membrane glycoprotein (GP) Ib. However, the diminished adhesion of SP treated FWP to collagen could still be increased in the presence of purified von Willebrand factor (vWF). This ability to vWF to increase FWP adhesion to collagen is defined as collagen cofactor (CCo). The adhesion of FWP to collagen was not affected by a monoclonal antibody (MAb) to GP IIb/IIIa (10E5), that inhibits ADP and collagen induced platelet aggregation. On the other hand, it was decreased by 50% by a MAb to GP Ib (6D1), that inhibits ristocetin induced platelet aggregation. Adhesion of FWP in buffer to collagen was completely inhibited by Ricinus communis agglutinin I or concanavalin A, while Lens culinalis agglutinin and wheat germ agglutinin showed 50% inhibition. The FWP adhesion to collagen in the presence of vWF (normal plasma) was unaffected by MAbs to GP IIb/IIIa (10E5, P2, HPL1) but was decreased to 32-38% by MAbs to GP Ib (6D1, AN51, HPL11). A MAb to vWF (CLB-RAg 35), that inhibits ristocetin induced binding of vWF to platelets, decreased the CCo of normal plasma by 70%. The MAb, CLB-RAg 201, that inhibits the binding of vWF to collagen, completely inhibited the CCo of normal plasma.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Glycoprotein Ib has a partial role in platelet-von Willebrand factor collagen interaction. 306 58

Tumor cell adhesion to endothelial cells, subendothelial matrix, and fibronectin is stimulated by the lipoxygenase metabolite of arachidonic acid, 12(S)-HETE, but not by 12(R)-HETE, 5-HETE or 15-HETE. Adhesion is also stimulated by the phorbol ester TPA, an effect inhibited by lipoxygenase but not cyclooxygenase inhibitors. TPA and 12(S)-HETE mediated adhesion is due, in part, to an integrin receptor (i.e., IRGpIIb/IIIa) related to the platelet glycoprotein IIb/IIIa complex and is inhibited by specific monoclonal and polyclonal antibodies against platelet IIb/IIIa. TPA and 12(S)-HETE stimulated adhesion is also inhibited by a lipoxygenase product of linoleic acid; i.e., 13-HODE. These results suggest bidirectional control of tumor cell adhesion by lipoxygenase products of arachidonic acid (increase) and linoleic acid (decrease).
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PMID:Lipoxygenase products regulate IRGpIIb/IIIa receptor mediated adhesion of tumor cells to endothelial cells, subendothelial matrix and fibronectin. 314 31

Type VI collagen is a subendothelial constituent that binds von Willebrand factor (vWF) and platelets. The interaction of platelets with type VI collagen and the roles of platelet glycoprotein (GP) receptors and vWF were studied under flow conditions using epi-fluorescent videomicroscopy coupled with digital image processing. We found that surface coverage was less than 6% on collagen VI at a relatively high-wall shear rate (1,000 s-1) and was approximately 60% at a low-wall shear rate (100 s-1). The molecular mechanisms involved in low-shear platelet binding were studied using monoclonal antibodies to platelet GPIb and GPIIb-IIIa, and polymeric aurin tricarboxylic acid. Anti-GPIIb-IIIa was the most effective in eliminating adhesion (surface coverage, 0.8%), followed by anti-GPIb (4.3%), and ATA (12.6%). Experiments with von Willebrand disease blood indicate that vWF is involved in platelet adhesion to collagen VI at 100 s-1. In the absence of vWF, there may be direct binding of platelet GPIIb-IIIa complexes to collagen VI. Adhesion and aggregation on collagen VI are different in shear rate dependence from collagen I. Our results suggest a possible role for collagen VI and vWF in platelet adhesion and aggregation in vascular regions with low shear rates.
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PMID:Platelet adhesion and aggregation on human type VI collagen surfaces under physiological flow conditions. 770 89

Platelet membrane glycoproteins Ib (GPIb) and IIb/IIIa (GPIIb/IIIa) bind soluble von Willebrand factor (vWf) after stimulation with ristocetin (GPIb) or with thrombin or ADP (GPIIb/IIIa). In fluid-phase, vWf does not bind to these platelet receptors without stimulation. In contrast, platelets adhere to solid-phase vWf without stimulation by ristocetin, adenosine diphosphate (ADP), or thrombin, and adhesion increases after stimulation by these agonists. The effect of monoclonal antibodies specific for GPIb (6D1) and GPIIb/IIIa (10E5 and HP1-1D) on platelet adhesion to solid-phase vWF was studied. Adhesion of radiolabeled, washed platelets (with washed red blood cells) aspirated at a constant wall shear rate of 1000 sec-1 through glass capillary tubes coated with purified human vWf was quantified. Unstimulated platelet adhesion was decreased 80% to 90% by blocking either the GPIb site or the GPIIb/IIIa site with 6D1 or 10E5, respectively, or with 6D1 and 10E5 together. Adhesion was not reduced significantly by HP1-1D (anti-GPIIb/IIIa). After stimulation with ADP or thrombin, the platelet adhesion was reduced by prior incubation with saturating concentrations of either 6D1 (61% reduction) or 10E5 (80% reduction), as well as with both 6D1 and 10E5 (80% reduction). After stimulation with ristocetin, the adhesion was reduced with either 6D1 (90% reduction) or 10E5 (90% reduction) or both 6D1 and 10E5 (90% reduction). Prior incubation with HP1-1D had minimal effect on platelet adhesion to vWF after stimulation with thrombin, ADP, or ristocetin.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Monoclonal antibodies to platelet glycoproteins Ib and IIb/IIIa inhibit adhesion of platelets to purified solid-phase von Willebrand factor. 805 92

We investigated the molecular mechanism(s) by which platelets adhere to an artificial surface exposed to plasma, using polystyrene microtiter plates pretreated with plasma. Washed platelets labelled with 51Cr were incubated with the plates under static conditions. Prostaglandin E1(PGE1) was added to the platelets to prevent platelet-platelet interactions. Adhesion required the presence of a divalent cation such as Mg++ or Ca++. Polyclonal anti-fibrinogen antibody inhibited adhesion by 70%. Polyclonal antibodies against fibronectin, vitronectin, von Willebrand's Factor, and the Fc portion of human IgG, had no effect on adhesion. Platelets adhered normally to a surface pretreated with plasma from a patient with severe von Willebrand's disease. No platelet adhesion occurred when the surface was pretreated with an afibrinogenemic plasma. Monoclonal antibodies against platelet membrane GPIIb-IIIa, potent inhibitors of ADP-induced fibrinogen binding to platelets, completely inhibited adhesion. Monoclonal antibodies against the GPIb alpha subunit and GPIc(VLA alpha 5) showed no inhibitory effects on adhesion. Platelets from a patient with Glanzmann's thrombasthenia (type I) did not adhere to the surface pretreated with normal plasma. These results suggest that plasma fibrinogen adsorbed onto the surface and that platelet membrane glycoprotein(GP)IIb-IIIa were responsible for adhesion in an activation-independent manner.
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PMID:Evidence that plasma fibrinogen and platelet membrane GPIIb-IIIa are involved in the adhesion of platelets to an artificial surface exposed to plasma. 813 6


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