Comparison of LHRH-peptidase and plasminogen activator activity in rat testis extracts

1997 ◽  
Vol 9 (7) ◽  
pp. 659 ◽  
Author(s):  
Mark P. Hedger ◽  
Michael D. Culler
Keyword(s):  
Plasminogen Activator ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Exchange Chromatography ◽  
Partial Purification ◽  
Plasmin Activity ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Gonadotrophin Releasing Hormone ◽  
Secreted Proteases

Testicular LHRH-peptidase and testicular urokinase-type plasminogen activator are Sertoli cell-secreted proteases which display similar molecular properties. However, there is relatively little information regarding the substrate specificity and potential cross-reactivity of these enzymes. Testicular extracts were prepared from homogenates of whole rat testes and assessed by LHRH-peptidase assay, and by radial caseinolysis assays for plasminogen activator and plasmin-like activity. Following partial purification of the protease activities in testicular extracts by gel filtration and ion-exchange chromatography, it was conrmed that testicular LHRH-peptidase and plasminogen activator are clearly separable. There was no detectable plasmin-like activity in the testicular extracts; however, the extracts were found to contain an inhibitor, or inhibitors, of both plasminogen activator and plasmin activity. In addition to LHRH and Gly 6 -substituted LHRH analogues, the partially purified LHRH-peptidase degraded both angiotensins I and II, but not the gonadotrophin-releasing-hormone-associated peptide derived from the LHRH precursor molecule. These properties of the LHRH-peptidase provide further evidence that it is a testis-specific prolyl endopeptidase, involved in regulating and/or limiting peptide activity in the testis.

Inhalation of urokinase-type plasminogen activator reduces airway remodeling in a murine asthma model

2009 ◽  
Vol 296 (3) ◽  
pp. L337-L346 ◽  
Author(s):  
Emi Kuramoto ◽  
Teruaki Nishiuma ◽  
Kazuyuki Kobayashi ◽  
Masatsugu Yamamoto ◽  
Yuko Kono ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Growth Factor ◽  
Plasminogen Activator ◽  
Airway Remodeling ◽  
Plasmin Activity ◽  
Matrix Deposition ◽  
Asthma Model ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Murine Asthma Model

The airway remodeling that occurs in asthma is characterized by an excess of extracellular matrix deposition in the submucosa, hyperplasia/hypertrophy of smooth muscle, goblet cell metaplasia, and accumulation of fibroblasts/myofibroblasts. The urokinase-type plasminogen activator (uPA)/plasmin system participates in pericellular proteolysis and is capable of directly degrading matrix components, activating latent proteinases, and activating growth factors. In a mouse ovalbumin (OVA) asthma model, we increased plasminogen activator activity in the lung by administering exogenous uPA or by using mice genetically deficient in the uPA inhibitor plasminogen activator inhibitor-1 (PAI-1) to assess the role of this system in asthma pathogenesis. After intraperitoneal OVA sensitization, mice inhaled OVA plus uPA (500 IU/mouse) or saline by ultrasonic nebulization for 3 wk. When studied 24 h after the final exposure, the groups with upregulated plasmin activity had significantly reduced subepithelial fibrosis within the airway walls and had decreased airway hyperresponsiveness (AHR) to methacholine. Morphometric analysis showed that subepithelial wall thickening of the bronchi (subepithelial area ratio) was also reduced, as were collagen and α-smooth muscle actin. Upregulation of plasmin activity also increased the level of hepatocyte growth factor activity in bronchoalveolar lavage fluid, whereas the release of transforming growth factor-β was decreased. The administration of uPA 1 wk after the last OVA inhalation also significantly reduced lung hydroxyproline content and AHR. These results show that enhancing uPA/plasmin activity lessens the airway remodeling in a murine asthma model.

PROPERTIES OF A HUMAN RECOMBINANT FUSION PROTEIN OF THE ‘FINGER’ DOMAIN OF TISSUE-TYPE PLASMINOGEN ACTIVATOR (t-PA) AND A TRUNCATED SINGLE CHAIN UROKINASE-TYPE PLASMINOGEN ACTIVATOR (scu-PA)

1987 ◽  
Author(s):  
D Gheysen ◽  
L Piérard ◽  
P Jacobs ◽  
H R Lijnen ◽  
A Bollen ◽  
...  
Keyword(s):  
Amino Acids ◽  
Plasminogen Activator ◽  
Gel Filtration ◽  
Tissue Type ◽  
Single Chain ◽  
Terminal Part ◽  
Tissue Type Plasminogen Activator ◽  
Reducing Conditions ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator

A hybrid between human tissue-type plasminogen activator (t-PA) and human single chain urokinase-type plasminogen activator (scu-PA) was obtained by ligation of cDNA fragments encoding the NH2-terminal amino acids 1 to 67 of t-PA and the COOH-ter-minal amino acids 136 to 411, of scu-PA. Both this chimaeric cDNA and cDNA encoding scu-PA were expressed in a mammalian system (HAK-cells) using bovine papilloma virus (BPV) derived vectors. Two stable cell lines were obtained which secreted the recombinant hybrid and the scu-PA at 1 μg/ml and 2 μg/ml u-PA related antigen respectively into the culture medium. Following purification by Zinc chelate Sepharose, immunoadsorption chromatography, benzamidine-Sepharose and Ultrogel AcA44 gel filtration, highly purified proteins were obtained with a yield of about 200 μg/1. SDS gel electrophoresis under reducing conditions showed single bands with M 43,000 and M 50,000 respectively. Following conversion to urokinase with plasmin, both proteins had a specific amidolytic activity comparable to that of natural scu-PA. Both proteins activated plasminogen directly with km1.4 and 0.5 μM and k2 0.0034 s and 0.0027 s . Neither protein bound specifically to fibrin.Thus the fusion of the finger-like domain of t-PA to the COOH-terminal part of scu-PA does not confer fibrin affinity of t-PA to this chimaeric protein. However, peptide material can be fused to the COOH-terminal part of scu-PA without perturbing its enzymatic properties.

scholarly journals Human tissue-type plasminogen activator. Production in continuous serum-free cell culture and rapid purification

1985 ◽  
Vol 226 (3) ◽  
pp. 631-636 ◽  
Author(s):  
E K O Kruithof ◽  
W D Schleuning ◽  
F Bachmann
Keyword(s):  
Plasminogen Activator ◽  
Human Tissue ◽  
Specific Activity ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Tissue Type ◽  
Single Chain ◽  
Serum Free ◽  
Tissue Type Plasminogen Activator ◽  
Type Plasminogen Activator

A simplified procedure for the production and purification of human tissue-type plasminogen activator (t-PA) is described. Bowes-melanoma cells were maintained in continuous serum-free culture. The cell nutrient consisted of Dulbecco's modified Eagle's medium (DMEM) supplemented with insulin (5 mg/litre), transferrin (5 mg/litre), progesterone (1 nM), cortisol (10 nM), aprotinin (2 X 10(4) units/litre) and a mixture of trace elements. t-PA accumulated in the culture medium at a rate of 40 units/day per ml and was harvested every third day. Cell losses during each harvest, leading to a steady decline of enzyme yields, were compensated for by treating the cells with 5% (v/v) fetal-bovine serum in DMEM every 6-8 weeks. t-PA was rapidly purified by a combination of cation-exchange chromatography and gel filtration. The procedure yielded mainly single-chain t-PA of a specific activity of 80 000 to 100 000 units/mg.

Urokinase type plasminogen activator and inhibitor type-1 plasma levels in colorectal cancer

2001 ◽  
Vol 120 (5) ◽  
pp. A599-A600 ◽  
Author(s):  
L HERSZENYI ◽  
F FARINATI ◽  
G ISTVAN ◽  
M PAOLI ◽  
G ROVERONI ◽  
...  
Keyword(s):  
Colorectal Cancer ◽  
Plasminogen Activator ◽  
Plasma Levels ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Inhibitor Type

Expression and Characterization of Clustered Charge-to-Alanine Mutants of Low Mr Single-Chain Urokinase-Type Plasminogen Activator

1994 ◽  
Vol 71 (01) ◽  
pp. 134-140 ◽  
Author(s):  
S Ueshima ◽  
P Holvoet ◽  
H R Lijnen ◽  
L Nelles ◽  
V Seghers ◽  
...  
Keyword(s):  
Plasminogen Activator ◽  
Solvent Accessibility ◽  
Site Directed Mutagenesis ◽  
Clot Lysis ◽  
Wild Type ◽  
Single Chain ◽  
Charged Amino Acids ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Pharmacokinetic Properties

SummaryIn an effort to modify the fibrinolytic and/or pharmacokinetic properties of recombinant low M r single-chain urokinase-type plasminogen activator (rscu-PA-32k), mutants were prepared by site-directed mutagenesis of clusters of charged amino acids with the highest solvent accessibility. The following mutants of rscu-PA-32k were prepared: LUK-2 (Lys 212, Glu 213 and Asp 214 to Ala), LUK-3 (Lys 243 and Asp 244 to Ala), LUK-4 (Arg 262, Lys 264, Glu 265 and Arg 267 to Ala), LUK-5 (Lys 300, Glu 301 and Asp 305 to Ala) and LUK-6 (Arg 400, Lys 404, Glu 405 and Glu 406 to Ala).The rscu-PA 32k moictic3 were expressed in High Five Ttichoplasiani cells, and purified to humugciicily from the conditioned cell culture medium, with recoveries of 0.8 to 3.7 mg/1. The specific fibrinolytic activities (220,000 to 300,000 IU/mg), the rates of plasminogen activation by the single-chain moieties and the rates of conversion In lwo chain moieties by plasmin were comparable for mutant and wild-type rscu PA 32k moieties, with the exception of LUK-5 which was virtually inactive. Equi-effective lysis (50% in 2 h) of 60 pi 125I-fibrin labeled plasma clots submerged in 0.5 ml normal human plasma was obtained with 0.7 to 0.8 μg/ml of wild-type or mutant rscu-PA-3?.k, except with LUK-5 (no significant lysis with 16 pg/ml). Following bolus injection in hamsters, all rscu-PA-32k moieties had a comparably rapid plasma clearance (1.3 to 2.7 ml/min), as a result of a short initial half-life (1.4 to 2.5 min). In hamsters with pulmonary embolism, continuous intravenous infusion over 60 min at a dose of 1 mg/kg, resulted in 53 to 72% clot lysis with the mutants, but only 23% with LUK-5, as compared to 36% for wild-type rscu-PA-32k.These data indicate that clustered charge-to-alanine mutants of rscu-PA-32k, designed to eliminate charged regions with the highest solvent accessibility, do not have significantly improved functional, fibrinolytic or pharmacokinetic properties.

Inhibition in Purified Systems and in Human Plasma of Chimaeric Plasminogen Activators Consisting of the NH2-Terminal Region of Tissue-Type Plasminogen Activator and the COOH-Terminal Region of UrokinaseType Plasminogen Activator

1988 ◽  
Vol 60 (02) ◽  
pp. 247-250 ◽  
Author(s):  
H R Lijnen ◽  
L Nelles ◽  
B Van Hoef ◽  
F De Cock ◽  
D Collen
Keyword(s):  
Plasminogen Activator ◽  
Rate Constants ◽  
Plasminogen Activators ◽  
Second Order ◽  
Tissue Type ◽  
Single Chain ◽  
Chain Molecules ◽  
Order Rate ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator

SummaryRecombinant chimaeric molecules between tissue-type plasminogen activator (t-PA) and single chain urokinase-type plasminogen activator (scu-PA) or two chain urokinase-type plasminogen activator (tcu-PA) have intact enzymatic properties of scu-PA or tcu-PA towards natural and synthetic substrates (Nelles et al., J Biol Chem 1987; 262: 10855-10862). In the present study, we have compared the reactivity with inhibitors of both the single chain and two chain variants of recombinant u-PA and two recombinant chimaeric molecules between t-PA and scu-PA (t-PA/u-PA-s: amino acids 1-263 of t-PA and 144-411 of u-PA; t-PA/u-PA-e: amino acids 1-274 of t-PA and 138-411 of u-PA). Incubation with human plasma in the absence of a fibrin clot for 3 h at 37° C at equipotent concentrations (50% clot lysis in 2 h), resulted in significant fibrinogen breakdown (to about 40% of the normal value) for all two chain molecules, but not for their single chain counterparts. Preincubation of the plasminogen activators with plasma for 3 h at 37° C, resulted in complete inhibition of the fibrinolytic potency of the two chain molecules but did not alter the potency of the single chain molecules. Inhibition of the two chain molecules occurred with a t½ of approximately 45 min. The two chain variants were inhibited by the synthetic urokinase inhibitor Glu-Gly-Arg-CH2CCl with apparent second-order rate constants of 8,000-10,000 M−1s−1, by purified α2-antiplasmin with second-order rate constants of about 300 M−1s−1, and by plasminogen activator inhibitor-1 (PAI-1) with second-order rate constants of approximately 2 × 107 M−1s−1.It is concluded that the reactivity of single chain and two chain forms of t-PA/u-PA chimaers with inhibitors is very similar to that of the single and two chain forms of intact u-PA.

Physical Exercise Induces Enhancement of Urokinase-Type Plasminogen Activator (u-PA) Levels in Plasma

1991 ◽  
Vol 65 (01) ◽  
pp. 082-086 ◽  
Author(s):  
G Dooijewaard ◽  
A de Boer ◽  
P N C Turion ◽  
A F Cohen ◽  
D D Breimer ◽  
...  
Keyword(s):  
Physical Exercise ◽  
Plasminogen Activator ◽  
Maximal Exercise ◽  
Normal Values ◽  
Bicycle Ergometer ◽  
Tissue Type ◽  
Healthy Male ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Fibrinolytic Potential

SummaryThe enhancement of the blood fibrinolytic potential by physical exercise is generally attributed to the release of tissue-type plasminogen activator (t-PA) from the vessel wall. In this study we have investigated the possible contribution of urokinase-type plasminogen activator (u-PA).Six healthy male volunteers (age 21–25 years) were screened for their ability to perform maximal exercise for their age-group for 12 min on a bicycle ergometer. Subsequently, on one occasion they were required to remain supine for 2 h (from 8.30 a. m. onwards) and on another they performed maximal exercise (from 9.00 a.m. onwards). During exercise an increase in u-PA antigen and plasmin-activatable pro-urokinase (proUK) activity, concurrent with t-PA antigen and euglobulin t-PA activity, was observed in all six volunteers, while at rest these parameters remained unaffected. Mean u-PA- and t-PA antigen increased, respectively, from 4.2 ± 1.0 ng/ml and 5.8 ± 2.1 ng/ml before exercise to 9.8 ± 3.0 ng/ml and 18.3 ± 3.8 ng/ml (peak). Mean plasminactivatable proUK activity and t-PA activity increased, respectively, from 2.1 ± 0.4 ng/ml and 0.3 ± 0.2 ng/ml before exercise to 4.3 ± 1.7 ng/ml and 7.2 ± 4.0 ng/ml (peak). The increases were statistically significant throughout (paired t-test, pre vs post, antigen P <0.005 and activity P <0.02). After cessation of exercise u-PA and t-PA declined concurrently to normal values with a 50"/" decay in about 5 min. In conclusion, we found that both u-PA antigen and plasmin-activatable proUK activity are, concurrently with t-PA, enhanced upon exercise and, therefore, we consider that u-PA also contributes to – and co-operates in – the enhancement of the blood fibrinolytic potential and activity under these conditions.

An Enzyme-Linked Immunosorbent Assay for Urokinase-Type Plasminogen Activator (u-PA) and Mutants and Chimeras Containing the Serine Protease Domain of u-PA

1992 ◽  
Vol 67 (01) ◽  
pp. 095-100 ◽  
Author(s):  
Paul J Declerck ◽  
Leen Van Keer ◽  
Maria Verstreken ◽  
Désiré Collen
Keyword(s):  
Serine Protease ◽  
Plasminogen Activator ◽  
Active Site ◽  
Enzyme Linked Immunosorbent Assay ◽  
Single Chain ◽  
Protease Domain ◽  
Serine Protease Domain ◽  
Type Plasminogen Activator ◽  
Urokinase Type Plasminogen Activator ◽  
Normal Human

SummaryAn enzyme-linked immunosorbent assay (ELISA) for quantitation of natural and recombinant plasminogen activators containing the serine protease domain (B-chain) of urokinase-type plasminogen activator (u-PA) was developed, based on two murine monoclonal antibodies, MA-4D1E8 and MA-2L3, raised against u-PA and reacting with non-overlapping epitopes in the B-chain. MA-4D1E8 was coated on microtiter plates and bound antigen was quantitated with MA-2L3 conjugated with horseradish peroxidase. The intra-assay, inter-assay and inter-dilution coefficients of variation of the assay were 6%, 15% and 9%, respectively. Using recombinant single-chain u-PA (rscu-PA) as a standard, the u-PA-related antigen level in normal human plasma was 1.4 ± 0.6 ng/ml (mean ± SD, n = 27).The ELISA recognized the following compounds with comparable sensitivity: intact scu-PA (amino acids, AA, 1 to 411), scu-PA-32k (AA 144 to 411), a truncated (thrombin-derived) scu-PA comprising A A 157 to 411, and chimeric t-PA/u-PA molecules including t-PA(AA1-263)/scu-PA(AA144-411), t-PA(AA1-274)/scu-PA(AA138-411) and t-PA(AA87-274)/scu-PA(AA138-411). Conversion of single-chain to two-chain forms of u-PA or inhibition of active two-chain forms with plasminogen activator inhibitor-1 or with the active site serine inhibitor phenyl-methyl-sulfonyl fluoride, did not alter the reactivity in the assay. In contrast, inactivation with α2-antiplasmin or with the active site histidine inhibitor Glu-Gly-Arg-CH2Cl resulted in a 3- to 5-fold reduction of the reactivity. When purified scu-PA-32k was added to pooled normal human plasma at final concentrations ranging from 20 to 1,000 ng/ml, recoveries in the ELISA were between 84 and 110%.The assay was successfully applied for the quantitation of pharmacological levels of scu-PA and t-PA(AA87_274)/scu-PA(AA138-411) in plasma during experimental thrombolysis in baboons.Thus the present ELISA, which is specifically dependent on the presence of the serine protease part of u-PA, is useful for measurement of a wide variety of variants and chimeras of u-PA which are presently being developed for improved thrombolytic therapy.

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