Affinity chromatography purification and partial characterization of phytohemagglutinin-receptor glycoproteins from porcine splenic lymphocytes

1985 ◽  
Vol 63 (9) ◽  
pp. 932-940 ◽  
Author(s):  
Gilles Dupuis ◽  
Jean-Pierre Doucet ◽  
Bânû Bastin ◽  
Jeannine Cardin

We describe the isolation of pig spleen lymphocyte glycoproteins that interact with phytohemagglutinin (PHA), the lectin from Phaseolus vulgaris. Purification was achieved by affinity chromatography of a Nonidet P-40 extract of the cells on a PHA – Affi-Gel 10 column. The retained glycoproteins were eluted with an acidic (pH 3.0) glycine buffer and represented 1.9–2.4% of the amount of protein applied to the column. They contained 20 ± 1.3% hexose and 1.7 ± 0.7% fatty acids, on a weight basis. Electrophoretic analyses (sodium dodecyl sulfate – polyacrylamide gel electrophoresis) showed the presence of major Coomassie blue positive bands with apparent molecular masses of 50–55, 75, 95, 130, and 155 kdaltons along with minor bands of 20–40, 42, 45, 60–65, 175, and 200–250 kdaltons. The purified PHA-receptor glycoproteins inhibited, in a dose-dependent manner, the incorporation of [3H]thymidine in pig lymphocytes cultured at a concentration of 106 cells/mL in the presence of PHA. A 50% inhibition was observed when 20 μg/mL of the glycoproteins was added to the lymphocyte cultures containing 0.5 μg/mL of PHA. Scatchard analysis of the binding of 125I-labelled PHA, in the presence of increasing amounts of the purified glycoproteins, showed a suppression of the binding of the lectin to high affinity sites of the cells, as evidenced by a change from biphasic to a linear profile. Results of binding suggested a competitive inhibition by a population of purified glycoproteins with a similar affinity for the lectin. The purified glycoproteins decreased PHA-dependent interleukin 2 (IL-2) production by pig lymphocytes as assayed with a IL-2 dependent murine cell line. It is suggested that the affinity-purified PHA-reactive glycoproteins are inhibitors of PHA-dependent cellular responses because they compete with PHA-receptor sites on the lymphocyte plasma membrane. A mouse antiserum raised against the purified glycoproteins inhibited PHA-induced lymphocyte activation, but did not stimulate lymphocytes when added alone to lymphocyte cultures or in combination with a antimouse antiserum.

1978 ◽  
Vol 39 (03) ◽  
pp. 616-563 ◽  
Author(s):  
Inge Clemmensen

SummaryHuman antithrombin III was purified from fresh human plasma by affinity chromatography on heparin-Sepharose®, affinity chromatography on concanavalin A Sepharose®, gel filtration on Ultrogel® AcA 34, ion exchange chromatography on DEAE A-50 Sephadex® and preparative agarose gel electrophoresis. The hydrolytic activity of urokinase (plasminogen activator from urine) on acetyl-glycyl-L-lysine methyl ester acetate (Ac-gly-lys-OMe Ac) was inhibited by antithrombin III in a slow time-dependent manner. Heparin accelerated the reaction between activator and inhibitor. Inhibition of catalytic activity was associated with the formation of an 1:1 molar complex between activator and inhibitor as revealed by sodium dodecyl sulphate polyacrylamide gel electrophoresis. The complex was also demonstrated by crossed Immunoelectrophoresis against anti-antithrombin III.


1981 ◽  
Vol 197 (3) ◽  
pp. 629-636 ◽  
Author(s):  
J L McKenzie ◽  
A K Allen ◽  
J W Fabre

Human and canine brain Thy-1 antigens were solubilized in deoxycholate and antigen activity was followed both by conventional absorbed anti-brain xenosera of proven specificity and by mouse monoclonal antibodies to canine and human Thy-1. It is shown that greater than 80% of Thy-1 activity in the dog and man binds to lentil lectin, that the mobility on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis of canine and human Thy-1 is identical with that of rat Thy-1 and that the Stokes radius in deoxycholate of canine and human brain Thy-1 is 3.0 nm and 3.25 nm respectively. Both lentil lectin affinity chromatography followed by gel-filtration chromatography on the one hand and monoclonal antibody affinity chromatography on the other gave high degrees of purification of the brain Thy-1 molecule in the dog and man, resulting in single bands staining for both protein and carbohydrate on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis (except for a slight contaminant of higher molecular weight staining for protein but not carbohydrate with human Thy-1 purified by lentil lectin and gel-filtration chromatography). Analysis of canine and human brain Thy-1 purified by monoclonal antibody affinity chromatography with additional gel filtration through Sephadex G-200 showed that these molecules had respectively 38% and 36% carbohydrate. The amino acid and carbohydrate compositions were similar to those previously reported for Thy-1 of the rat and mouse, the main point of interest being the presence in canine and human brain Thy-1 of N-acetylgalactosamine, which has been reported in rat and mouse brain Thy-1 but not in Thy-1 from other tissues.


Blood ◽  
1986 ◽  
Vol 68 (4) ◽  
pp. 810-817
Author(s):  
KJ Balazovich ◽  
JE Smolen ◽  
LA Boxer

Ca2+-dependent and phospholipid-dependent protein kinase (PKC) is a receptor for and is activated by phorbol esters. This enzyme is reportedly involved in the mechanism of superoxide anion (O2-) production and the release of intracellular granule contents from human neutrophils. As previously reported by others, we found that greater than 75% of the total cellular PKC activity existed in a soluble form in untreated neutrophils and that this activity was enhanced in a dose- dependent manner by phorbol 12-myristate 13-acetate (PMA) and by phorbol 12,13-dibutyrate (PDBu). Furthermore, mezerein, an analogue of PMA that is thought to be a competitive inhibitor, did not activate PKC, and on the contrary, inhibited PMA-stimulated activity in a dose- dependent manner. Pretreatment of intact neutrophils with PMA or PDBu caused the “translocation” of PKC activity to the insoluble cell fraction; PKC translocation was not detected after mezerein stimulation at any of the tested concentrations. Neither did mezerein cause an increase in intracellular Ca2+, as monitored by Quin 2 fluorescence. Both phorbol esters and mezerein stimulated intact neutrophils to generate O2- and release lysosomal enzymes into the extracellular medium. Finally sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis demonstrated key differences in the patterns of endogenous phosphoproteins of neutrophils stimulated with phorbol as compared with mezerein. We therefore suggest that PKC activation may not be the only pathway required to elicit neutrophil responses.


1993 ◽  
Vol 13 (4) ◽  
pp. 2061-2068
Author(s):  
H Shirataki ◽  
K Kaibuchi ◽  
T Sakoda ◽  
S Kishida ◽  
T Yamaguchi ◽  
...  

In a previous study (H. Shirataki, K. Kaibuchi, T. Yamaguchi, K. Wada, H. Horiuchi, and Y. Takai, J. Biol. Chem. 267:10946-10949, 1992), we highly purified from bovine brain crude membranes the putative target protein for smg p25A/rab3A p25, a ras p21-related small GTP-binding protein implicated in neurotransmitter release. In this study, we have isolated and sequenced the cDNA of this protein from a bovine brain cDNA library. The cDNA had an open reading frame encoding a protein of 704 amino acids with a calculated M(r) of 77,976. We tentatively refer to this protein as rabphilin-3A. Structural analysis of rabphilin-3A revealed the existence of two copies of an internal repeat that were homologous to the C2 domain of protein kinase C as described for synaptotagmin, which is known to be localized in the membrane of the synaptic vesicle and to bind to membrane phospholipid in a Ca(2+)-dependent manner. The isolated cDNA was expressed in COS7 cells, and the encoded protein was recognized with an anti-rabphilin-3A polyclonal antibody and was identical in size with rabphilin-3A purified from bovine brain by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Moreover, both rabphilin-3A purified from bovine brain and recombinant rabphilin-3A made a complex with the GTP gamma S-bound form of rab3A p25 but not with the GDP-bound form of rab3A p25. Immunoblot and Northern (RNA) blot analyses showed that rabphilin-3A was highly expressed in bovine and rat brains. These results indicate that rabphilin-3A is a novel protein that has C2 domains and selectively interacts with the GTP-bound form of rab3A p25.


1992 ◽  
Vol 262 (4) ◽  
pp. F639-F646 ◽  
Author(s):  
A. V. Cybulsky ◽  
P. R. Goodyer ◽  
M. D. Cyr ◽  
A. J. McTavish

Proliferation of glomerular epithelial cells (GEC) and release of prostaglandins (PG) and thromboxane (Tx) A2 may occur in glomerular injury. We studied the relationship of eicosanoids to epidermal growth factor (EGF)-induced proliferation of rat GEC in culture. After 48 h of serum-deprivation, EGF stimulated [3H]thymidine incorporation ninefold above serum-deprived cells. Inhibition of cyclooxygenase with indomethacin or of Txsynthase with OKY-046 decreased the proliferative effect of EGF by 50 and 38%, respectively. The effect of indomethacin was reversed by addition of PGE2. Synthesis of PGE2, PGF2 alpha, and TxA2 by serum-deprived GEC was not enhanced by EGF. Scatchard analysis of 125I-EGF binding to GEC demonstrated two populations of EGF receptors; the high-affinity site had a dissociation constant (Kd) of 444 pM and 24,864 receptors/cell. EGF receptor autophosphorylation (reflecting receptor activation) was studied by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblotting of GEC membrane proteins with anti-phosphotyrosine antibody. EGF increased phosphorylation of a protein of approximately 170 kDa, which comigrated with proteins immunoprecipitated from [35S]methionine-labeled GEC with antibodies to EGF receptor. Indomethacin and OKY-046 decreased the EGF-dependent phosphorylation of the 170-kDa protein, and this decrease was overcome by addition of PGE2. Indomethacin and OKY-046 did not, however, reduce 125I-EGF binding. Thus, in GEC, the basal synthesis of eicosanoids enhanced EGF-induced proliferation. This effect appears to be due to enhancement of EGF receptor activation.


1994 ◽  
Vol 267 (2) ◽  
pp. E242-E249
Author(s):  
B. M. Wilkes ◽  
C. M. Macica ◽  
P. F. Mento

Endothelin-1-(1-21), a potent pressor peptide, is transcribed as big endothelin-(1-38) and converted to active peptide by endothelin-converting enzyme. The current investigation tested the hypothesis that human fetoplacental blood vessels convert big endothelin-1 to active peptide and that fetoplacental blood vessels respond to endothelin-1 by binding of the peptide to specific receptor sites. In the isolated perfused placental cotyledon the addition of big endothelin-1 to the perfusate caused a time-dependent increase in perfusion pressure that corresponded to the appearance of endothelin-1 in the perfusate. The properties of human placental endothelin-1 receptors were defined in binding studies performed on a plasma membrane fraction of small arteries (<1.0 mm) dissected from the placenta. Binding was saturable, reached steady state by 3 h at 25 degrees C, and was linear with protein concentration. Scatchard analysis of binding data indicated a single class of high-affinity binding sites with a dissociation constant of 27.6 +/- 2.3 pM and a density of 856 +/- 119 fmol/mg protein (n = 5). The potency order for competitive inhibition of the binding of 125I-labeled endothelin-1 [endothelin-1 = endothelin-2 > endothelin-3 = sarafotoxin S6b >> big endothelin-1 (human) = big endothelin-1 (porcine)] is most consistent with a type A endothelin receptor subtype. Phenylephrine, bradykinin, norepinephrine, atrial natriuretic factor, diltiazem, U-46619, and angiotensin II did not displace 125I-endothelin-1 binding. Endothelin receptors were shown to have an approximate molecular weight of 36,600 by polyacrylamide gel electrophoresis.(ABSTRACT TRUNCATED AT 250 WORDS)


1972 ◽  
Vol 129 (1) ◽  
pp. 83-89 ◽  
Author(s):  
Ragnar Flengsrud ◽  
Bjarne Østerud ◽  
Hans Prydz

1. The supernatant obtained by centrifugation of a rat liver homogenate at 100000g for 1h contained a heat-labile macromolecular inhibitor of the thrombin–fibrinogen reaction. 2. The inhibitor was purified to electrophoretic homogeneity by repeated preparative polyacrylamide disc electrophoresis. Inhibition was observed with purified inhibitor equivalent to about 1μg of protein/ml. 3. The inhibitor had a pI of 3.50–3.75, a molecular weight (from sodium dodecyl sulphate–polyacrylamide-gel electrophoresis) of 72000±3000 and was inactivated by p-hydroxymercuribenzoate or 5,5′-dithiobis-(2-nitrobenzoic acid). 4. Kinetic studies revealed a non-competitive inhibition, with the inhibitor probably acting on the thrombin–fibrinogen complex.


Blood ◽  
1989 ◽  
Vol 73 (5) ◽  
pp. 1202-1206 ◽  
Author(s):  
MG Bolyard ◽  
ST Lord

Abstract The human fibrinogen B beta chain was expressed in Escherichia coli to study the functions of fibrinogen associated with this subunit. Recombinant B beta chains were expressed at 100 ng/mL in an IPTG- dependent manner. A first cistron sequence, inserted into the expression vector 5′ to the B beta chain cDNA, was required to express the protein. Recombinant B beta chains were expressed within five minutes after induction with IPTG and were soluble in physiologic buffers. The recombinant B beta chains migrated on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) at a rate identical to B beta chains from fibrinogen treated with N-glycanase. Recombinant B beta chains were cleaved by thrombin, as demonstrated by the loss of cross-reactivity with a monoclonal antibody (MoAb) specific for the undigested B beta 1–42 fragment. The levels of expression of the B beta chain were much lower than those reported previously for the gamma chain of fibrinogen expressed in a similar vector in E coli. However, these levels are sufficient to allow further characterization of this fibrinogen subunit.


1994 ◽  
Vol 267 (5) ◽  
pp. L618-L624 ◽  
Author(s):  
A. Gunther ◽  
M. Kalinowski ◽  
A. Elssner ◽  
W. Seeger

Polymerization of fibrin in the presence of pulmonary surfactant was recently noted to induce incorporation of phospholipids into the insoluble clot material, thereby effecting severe loss of surface activity (W. Seeger, A. Elssner, A. Gunther, H.-J. Kramer, and H. O. Kalinowski. Am. J. Respir. Cell Mol. Biol. 9: 213'220, 1993). In the present study, we investigated the influence of such incorporation of calf lung surfactant extract (CLSE) on the enzymatic cleavage of the fibrin network with the use of plasmin, trypsin, or elastase. Employing a fibrin-plate assay, the proteolytic release of radioactivity originating from 125I-labeled fibrinogen was assessed, and the pattern of split products was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. Surface activity of CLSE was measured in the pulsating bubble surfactometer. When incorporated into the fibrin clot, CLSE inhibited the cleavage of fibrin by all proteases in a dose-dependent manner without affecting the profile of scission products. Inhibition of plasmin-induced clot lysis was also noted on incorporation of CLSE into clotted plasma and on incorporation of dipalmitoylphosphatidylcholine into fibrin polymers. In contrast, corresponding concentrations of CLSE added to the incubation medium after preformation of the fibrin matrix did not substantially influence the kinetics of fibrinolysis. CLSE incorporation into the nascent fibrin clot resulted in complete loss of surface activity, but adsorption and surface tension-lowering properties were largely restored by subsequent plasmic clot lysis. Arising fibrin split products were shown to display similar inhibitory strength on CLSE surface activity compared with fibrinogen split products.(ABSTRACT TRUNCATED AT 250 WORDS


1988 ◽  
Vol 118 (1) ◽  
pp. 47-NP ◽  
Author(s):  
W. D. Booth ◽  
C. A. White

ABSTRACT Pheromaxein, the 16-androstene steroid-binding protein with a relative molecular mass of 15 000 was isolated in sub-milligram quantities from the submaxillary gland and saliva of the Gottingen miniature boar, after a fourfold purification involving the following methods: ultrafiltration for submaxillary gland cytosols and ethanol precipitation for saliva, Concanavalin-A-Sepharose affinity chromatography, sodium dodecyl sulphate polyacrylamide gel electrophoresis, 'Extractigel-D' affinity chromatography (to remove sodium dodecyl sulphate) and fast protein-liquid chromatography. Yields of purified pheromaxein obtained after fast protein-liquid chromatography represented 10–20% of total protein present in an ultrafiltrate of a submaxillary gland cytosol. Fast protein-liquid chromatography separated the α- and β-charge isomers of pheromaxein which were shown to have isoelectric points of 4·78 and 5·35 respectively on flat-bed isoelectric focusing. Some data are provided for the variable occurrence of the isomeric forms of pheromaxein in relation to different breeds of pig. Five 16-unsaturated steroids showed the highest binding to pheromaxein. Other steroids of the 5α- and 5β-androstane series also showed some binding to pheromaxein, i.e. 17β-hydroxy-5α-androstan-3-one (19·2%), with 5α-androstan-3-one, which has a similar urinous odour to 5α-androst-16-en-3-one, showing the greatest binding (42·6%) relative to 5α-androst-16-en-3-one (100%). J. Endocr. (1988) 118, 47–57


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