Role of carbohydrate and protein in the binding of tissue-type plasminogen activator to the human mannose receptor

Tissue-type plasminogen activator (tPA) is one of the components of the plasminogen-plasmin (PLG-PLA) system, better known as fibrinolytic system for its role in the blood clot lysis. It has been demonstrated recently that the activation of plasminogen into the protease plasmin during the sperm-oocyte interaction in the pig and cow decreases the percentages of penetration and increases monospermy (Mondéjar et al. 2012). However, in the mouse species, it was showed that PLG-PLA system enhances fertilization (Huarte et al. 1993). Expression of tPA has been described in rat oocytes (Bicsak et al. 1989) and cumulus cells (Ny et al. 1987; O’Connell et al. 1987), but no clear evidence about its expression in mouse, pig, and cow oocytes or cumulus cells is available. We hypothesised that differences in the effect of PLG-PLA system on fertilization results between the species mentioned above could be related to differences in tPA expression. The aim of this study was the detection of mRNA encoding tPA in oocytes and cumulus cells in mouse, pig, and cow by molecular analysis. Total RNA was obtained from oocytes and cumulus cells and cDNA was synthesised with an oligo-dT as primer. These cDNAs were used as template in RT-PCR amplifications using specific primers designed based on the GenBank sequence for Mus musculus, Sus scrofa, and Bos taurus tPA (NM_ 008872, NM_214054, NM_174146, respectively). The results of this study showed a different expression in the 3 studied species. In mouse, amplicon encoding tPA was detected in oocytes and cumulus cells. In cow and pig, tPA transcripts were obtained only in cumulus cells. The relation between the differences in the tPA expression pattern and the role of PLG-PLA system on fertilization remains to be investigated. This study was supported by MICINN (AGL2009-12512-C02-01-02).

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Cytosolic Tissue-Type Plasminogen Activator (T-Pa) Levels in Breast Tumors and Hormone Dependence. Role of Ps2

The International Journal of Biological Markers ◽

10.1177/172460089400900409 ◽

1994 ◽

Vol 9 (4) ◽

pp. 251-253 ◽

Cited By ~ 5

Author(s):

A. Ruibal ◽

A. Alvarez ◽

B. Fernández Llana ◽

Ma Fernández Fernández ◽

Ma C. Roiz ◽

...

Keyword(s):

Plasminogen Activator ◽

Breast Tumors ◽

Tissue Type ◽

Hormone Dependence ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

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Cluster mannosides can inhibit mannose receptor-mediated tissue-type plasminogen activator degradation by both rat and human cells

Hepatology ◽

10.1002/hep.510260531 ◽

1997 ◽

Vol 26 (5) ◽

pp. 1303-1310

Author(s):

F Noorman ◽

M M Barrett-Bergshoeff ◽

E A L Biessen ◽

E van de Bilt ◽

T J C van Berkel ◽

...

Keyword(s):

Plasminogen Activator ◽

Mannose Receptor ◽

Human Cells ◽

Tissue Type ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

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Increased Clearance Explains Lower Plasma Levels of Tissue-Type Plasminogen Activator by Estradiol: Evidence for Potently Enhanced Mannose Receptor Expression in Mice

Blood ◽

10.1182/blood.v94.4.1330.416k19_1330_1336 ◽

1999 ◽

Vol 94 (4) ◽

pp. 1330-1336

Author(s):

Mirian Lansink ◽

Miek Jong ◽

Martin Bijsterbosch ◽

Marian Bekkers ◽

Karin Toet ◽

...

Keyword(s):

Plasminogen Activator ◽

Clearance Rate ◽

Plasma Levels ◽

Inverse Relationship ◽

Mannose Receptor ◽

Receptor Expression ◽

Tissue Type ◽

Lower Plasma ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

Several clinical studies have demonstrated an inverse relationship between circulating levels of estrogen and tissue-type plasminogen activator (t-PA). The present study was designed to test the hypothesis that estrogens lower plasma levels of t-PA by increasing its clearance from the bloodstream. 17-Ethinyl estradiol (EE) treatment resulted in a significant increase in the clearance rate of recombinant human t-PA in mice (0.46 mL/min in treated mice v 0.32 mL/min in controls; P < .01). The clearance of endogenous, bradykinin-released t-PA in rats was also significantly increased after EE treatment (area under the curve [AUC], 24.9 ng/mL · min in treated animals v 31.9 ng/mL · min in controls; P < .05). Two distinct t-PA clearance systems exist in vivo: the low-density lipoprotein receptor-related protein (LRP) on liver parenchymal cells and the mannose receptor on mainly liver endothelial cells. Inhibition of LRP by intravenous injection of receptor-associated protein (RAP) as a recombinant fusion protein with Salmonella japonicum glutathione S-transferase (GST) significantly retarded t-PA clearance in control mice (from 0.41 to 0.25 mL/min; n = 5, P < .001) and EE-treated mice (from 0.66 to 0.35 mL/min; n = 5, P < .005), but did not eliminate the difference in clearance capacity between the 2 experimental groups. Similar results were obtained in mice in which LRP was inhibited via overexpression of the RAP gene in liver by adenoviral gene transduction. In contrast, administration of mannan, a mannose receptor antagonist, resulted in identical clearances (0.22 mL/min in controls and 0.24 mL/min in EE-treated mice). Northern blot analysis showed a 6-fold increase in mannose receptor mRNA expression in the nonparenchymal liver cells of EE-treated mice, whereas the parenchymal LRP mRNA levels remained unchanged. These findings were confirmed at the protein level by ligand blotting and Western blotting analysis. Our results demonstrate that EE treatment results in increased plasma clearance rate of t-PA via induction of the mannose receptor and could explain for the inverse relationship between estrogen status and plasma t-PA concentrations as observed in humans.

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Evidence for carbohydrate-independent endocytosis of tissue-type plasminogen activator by liver cells

Biochemical Journal ◽

10.1042/bj2850799 ◽

1992 ◽

Vol 285 (3) ◽

pp. 799-804 ◽

Cited By ~ 5

Author(s):

E Stang ◽

N Roos ◽

M Schlüter ◽

T Berg ◽

J Krause

Keyword(s):

Plasminogen Activator ◽

Liver Cell ◽

Hepatic Clearance ◽

Mannose Receptor ◽

Cell Types ◽

Tissue Type ◽

Side Chains ◽

Tissue Type Plasminogen Activator ◽

Hepatic Cells ◽

Type Plasminogen Activator

In the liver, tissue-type plasminogen activator (t-PA) is endocytosed by hepatic parenchymal (PC), endothelial (EC) and Kupffer (KC) cells. Although the endocytosis is receptor-mediated, it remains a matter of discussion which receptors are involved in this catabolic process. To evaluate the role of a protein-specific receptor, as well as the possible involvement of the galactose receptor on PC and the mannose receptor on EC, we have employed different glycosylation variants of t-PA in biochemical and immunocytochemical studies. Partial or total removal of carbohydrate side-chains by endoglycosidases did not prevent clearance and hepatic endocytosis of t-PA by either of the liver cell types. Blockade of the galactose and mannose receptors by co-application of a large excess of the glycoprotein ovalbumin remained without effect on the binding and uptake of t-PA by hepatic cells. However, the contribution of different liver cell types to the hepatic clearance of t-PA was to a certain extent dependent on the type of oligosaccharide chains removed. The mannose receptor on EC is partially responsible for the clearance of t-PA by this cell type, whereas the galactose receptor does not seem to be involved in this process. The results obtained in this study further demonstrate that the major portion of the hepatic catabolism of t-PA is independent of its carbohydrate side-chains.

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The Possible Role of Tissue-Type Plasminogen Activator (tPA) and tPA Blockers in the Pathogenesis and Treatment of Alzheimer's Disease

Journal of Molecular Neuroscience ◽

10.1385/jmn:20:3:287 ◽

2003 ◽

Vol 20 (3) ◽

pp. 287-290 ◽

Cited By ~ 12

Author(s):

Jerry P. Melchor ◽

Robert Pawlak ◽

Zulin Chen ◽

Sidney Strickland

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Plasminogen Activator ◽

Tissue Type ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator

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The Role of the Finger Domain of Tissue-type Plasminogen Activator (t-PA) and Plasminogen Activator Inhibitor 1 (PAI-1) in Initiation and Progression of Thrombolysis

Thrombosis and Haemostasis ◽

10.1055/s-0038-1648981 ◽

1994 ◽

Vol 72 (06) ◽

pp. 900-905 ◽

Cited By ~ 3

Author(s):

Harold A R Stringer ◽

Peter van Swieten ◽

Anton J G Horrevoets ◽

Annelies Smilde ◽

Hans Pannekoek

Keyword(s):

Plasminogen Activator ◽

Plasminogen Activator Inhibitor ◽

Tissue Type ◽

Clot Lysis ◽

Plasminogen Activator Inhibitor 1 ◽

Tissue Type Plasminogen Activator ◽

Type Plasminogen Activator ◽

Activator Inhibitor ◽

Pai 1

SummaryWe further investigated the role of the finger (F) and the kringle-2 (K2) domains of tissue-type plasminogen activator (t-PA) in fibrin-stimulated plasminogen activation. To that end, the action of purified (wt) t-PA or of variants lacking F (del.F) or K2 (del.K2) was assessed either in a static, human whole blood clot-lysis system or in whole blood thrombi generated in the “Chandler loop”. In both clot-lysis systems, significant differences were observed for the initiation of thrombolysis with equimolar concentrations of the t-PA variants. A relatively minor “lag phase” occurred in thrombolysis mediated by wt t-PA, whereas a 6.4-fold and 1.6-fold extension is found for del.F and del.K2, respectively. We observed identical lag-times, characteristic for each t-PA variant, in platelet-rich heads and in platelet-poor tails of thrombi. Since plasminogen activator inhibitor 1 (PAI-1) is preferentially retained in the platelet-rich heads, we conclude that the inhibitor does not interfere with the initial stage of thrombolysis but exerts its action in later stages, resulting in a reduction of the rate of clot lysis. A complementation clot-lysis assay was devised to study a potential interplay of del.F and del.K2. Accordingly, clot lysis was determined with combinations of del.F and del.K2 that were inversely varied in relation to equipotent dosage to distinguish between additive, antagonistic or synergistic effects of these variants. The isobole for combinations of del.F and del.K2 shows an independent, additive action of del.F and del.K2 in clot lysis. Under the conditions employed, namely a relatively high concentration of fibrin and Glu-plasminogen and a low concentration of t-PA variant, our data show: i) the crucial role of the F domain and the lack of effect of PAI-1 in initiation of thrombolysis, ii) the lack of importance of the fibrimbinding domains of t-PA and the regulatory role of PAI-1 in advanced stages of thrombolysis.

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