Isolation and Partial Characterization of Equine Antithrombin III.

Author(s):  
D.W. Estry ◽  
T.G. Bell ◽  
G.H. Tishkoff ◽  
J.C. Mattson ◽  
S.C. Estry

A protein analogous to human antithrombin III was isolated from fresh horse plasma. The procedure for purification was a modification of Thaler and Schmer’s two-step isolation procedure. The horse protein was homogeneous on 7.5% SDS-PAGE gels and had a molecular weight of 62,000 to 64,000 daltons in both reducing and non-reducing systems (human; 62,300). Rabbit anti-human antithrombin III was used to demonstrate a line of partial identity by Immunoelectrophoresis between the horse and human protein. The horse protein rapidly neutralizes human thrombin (34,000 daltons) and the reaction appears to be greatly potentiated by heparin. In order to establish the formation of 1:1 covalent stoichiometric complex between horse AT III and thrombin (IIa), time studies were run in the presence and absence of heparin. AT III (62,000) at 15 seconds, 2, 5, 10 and 60 minutes formed a stable complex with thrombin (32,000) having a molecular weight of 86,000 daltons. Additional bands developing with time are due to the autolytic capabilities of the uncomplexed IIa. The major autolytic band had a molecular weight of 70,000 daltons. Addition of heparin potentiated the interaction although it did not change the stoichio-metry of the complexes formed. The data accumulated to date demonstrates the similarities between the human and horse protein and the possibilities of using the horse as a model system for the evaluation of AT III replacement therapy in vivo.

1979 ◽  
Author(s):  
D. W. Estry ◽  
T. G. Bell ◽  
G. H. Tishkoff ◽  
J. C. Mattson ◽  
S. C. Estry

A protein analogous to human antithrombin III was isolated from fresh horse plasma. The procedure for purification was a modification of Thaler and Schmer’s two-step isolation procedure. The horse protein was homogeneous on 7.5% SDS-PAGE gels and had a molecular weight of 62,000 to 64,000 daltons in both reducing and non-reducing systems (human; 62,300). Rabbit anti-human antithrombin III was used to demonstrate a line of partial identity by immunoelectrophoresis between the horse and human protein. The horse protein rapidly neutralizes human thrombin (34,000 daltons) and the reaction appears to be greatly potentiated by heparin. in order to establish the formation of 1:1 covalent stoichiometric complex between horse AT III and thrombin (IIa), time studies were run in the presence and absence of heparin. AT III (62,000) at 15 seconds, 2, 5, 10 and 60 minutes formed a stable complex with thrombin (32,000) having a molecular weight of 86,000 daltons. Additional bands developing with time are due to the autolytic capabilities of the uncomplexed IIa. The major autolytic band had a molecular weight of 70,000 daltons. Addition of heparin potentiated the interaction although it did not change the stoichiometry of the complexes formed. The data accumulated to date demonstrates the similarities between the human and horse protein and the possibilities of using the horse as a model system for the evaluation of AT III replacement therapy in vivo.


1981 ◽  
Author(s):  
D Estry ◽  
J C Mattson ◽  
T G Bell ◽  
G H Tishkoff

The rabbit is a well established model for studying the disseminated intravascular coagulation (DIC) associated with endotoxic syndromes. In order to establish the role of antithrombin III (AT III) in the modulation of DIC in the rabbit, characterization of rabbit AT III was undertaken. Rabbit antithrombin III, isolated according to modifications of the method of Thaler and Schmer, has a molecular weight comparable to that of human AT III (62,000 daltons) as measured by mobility on SDS-PAGE gels. Mixtures of rabbit and human AT III co-migrate as a single band on 7.5% SDS-PAGE gels. Rabbit AT III possesses both progressive and heparin activated (immediate) antithrombin activity in assays using human thrombin. Antisera raised against rabbit AT III demonstrates no cross reactivity with human AT III suggesting that despite physiologic and molecular weight similarities, antigenic differences are present. Incubation of rabbit antithrombin III with specific antisera, either prior to or after addition of heparin, did not alter the ability of antithrombin III to inhibit thrombin in either the immediate or progressive assays indicating that the antigenic determinants are not found in either the heparin binding or active thrombin binding sites. Crossed immunoelectrophoresis (IEP) demonstrates that antisera to rabbit AT III reacts with both free rabbit antithrombin III and AT III-thrombin complexes and can therefore be used in immunologic assays to quantitate total rabbit AT III (bound and free) and in crossed IEP to demonstrate the mobility of both free and complexed AT III.


1977 ◽  
Vol 38 (02) ◽  
pp. 0494-0503 ◽  
Author(s):  
D. S Pepper ◽  
D Banhegyi ◽  
J. D Cash

SummaryAntithrombin III (AT III) complexes were isolated from human serum by affinity chromatography and gel filtration. In the first step of the preparation, using heparin-agarose chromatography, we observed that the complexed form of AT III bound less strongly to the gel than the free form and that about half of the AT III was free. With further purification a 2.5 × 105 molecular weight complex was isolated. Using 125I labelled human thrombin, this complex was radioactive indicating the presence of thrombin. Only in a synthetic thrombin-AT III system was a 9 × 104 molecular weight complex detected, but not in serum. These facts suggest that in serum AT III complexes may exist in a polymeric form. Also, an AT III antigen derived from the original AT III molecule, but not complexed, was isolated which may be a degradation product.Abbreviations used: AT-III, antithrombin III. Hepes, N-2-Hydroxyethylpiperazine-N-2-Ethanesulphonic acid.


1985 ◽  
Vol 101 (3) ◽  
pp. 1144-1152 ◽  
Author(s):  
P Collin-Osdoby ◽  
W S Adair

Chlamydomonas flagellar sexual agglutinins are responsible for the adhesion of opposite mating-type (plus and minus) gametes during the first stages of mating. Purification and partial characterization of the plus agglutinin was previously reported (Adair, W. S., C. J. Hwang, and U. W. Goodenough, 1983, Cell, 33:183-193). Here we characterize the purified minus molecule. We show it to be a high molecular weight, hydroxyproline-rich glycoprotein that migrates in the 3% stacking region of an SDS-polyacrylamide gel and is absent from two nonagglutinating minus mutants. Plus and minus agglutinins are remarkably similar, although nonidentical, in amino acid composition, molecular morphology, and reactivity in vivo and in vitro with monoclonal antibodies raised against the plus agglutinin. Moreover, the adhesiveness of both plus and minus agglutinins, when coupled to agarose beads, is abolished by thermolysin, trypsin, periodate, alkaline borohydride, reducing agents, or heat, but unaffected by exo- or endoglycosidases. The minus agglutinin, however, migrates just ahead of the plus molecule on SDS PAGE, is excluded from an anion-exchange (Mono Q) column, elutes earlier during hydrophobic interaction (Bio-gel TSK Phenyl 5PW) chromatography, and is sensitive to chymotrypsin digestion (unlike the plus agglutinin); therefore, it differs from the plus agglutinin in apparent molecular weight, net charge, relative hydrophobicity and proteolytic susceptibility. Nevertheless, our results generally demonstrate a high degree of homology between these complementary cell-cell recognition/adhesion molecules, which suggests that they are specified by genes that have a common evolutionary origin.


1987 ◽  
Author(s):  
H Erdjument ◽  
D A Lane ◽  
A M Flynn ◽  
H Ireland ◽  
M Panico ◽  
...  

It has been shown previously that antithrombin III Northwick Park (AT III NWP) has reduced ability to inactivate thrombin and is characterised by an additional anodal component on crossed immunoelectrophoresis. We have applied plasma from an affected family member to heparin-Sepharose and eluted the AT III with a salt gradient. Evidence will be presented that the anodal component has* higher affinity for heparin than normal AT III. Furthermore, this variant component is present in plasma as a MW >120,000 inactive complex whose tryptic peptide FAB map contains numerous signals not characteristic of normal AT . 111 . This complex can be reduced with dithiothreitol to two non identical bands on SDS PAGE with MW ~60,000, only one of which reacts with anti-AT III. Using ion-exchange chromatography and HPLC these two components have been isolated and separated. The N-terminal sequence of the protein that does not react with anti-AT III is believed to be Asp-Ala-His-Ile-Ser-Glu. Structural investigations on the variant AT III are underway.


1986 ◽  
Vol 34 (2) ◽  
pp. 209-214 ◽  
Author(s):  
J U Alles ◽  
K Bosslet

A new monoclonal antibody (moab BW 200) of IgG3 kappa-isotype was generated which recognizes an epitope located on an antigen molecule restricted to human neoplastic and non-neoplastic endothelial cells. The molecular weight of the antigen was determined using immunoprecipitation analysis followed by SDS-PAGE. Despite its similar molecular weight to FVIII-RAG, the antigen detected by moab BW 200 was shown to be different from FVIII-RAG.


1998 ◽  
Vol 66 (9) ◽  
pp. 4374-4381 ◽  
Author(s):  
John C. McMichael ◽  
Michael J. Fiske ◽  
Ross A. Fredenburg ◽  
Deb N. Chakravarti ◽  
Karl R. VanDerMeid ◽  
...  

ABSTRACT The UspA1 and UspA2 proteins of Moraxella catarrhalisare potential vaccine candidates for preventing disease caused by this organism. We have characterized both proteins and evaluated their vaccine potential using both in vitro and in vivo assays. Both proteins were purified from the O35E isolate by Triton X-100 extraction, followed by ion-exchange and hydroxyapatite chromatography. Analysis of the sequences of internal peptides, prepared by enzymatic and chemical cleavage of the proteins, revealed that UspA1 and UspA2 exhibited distinct structural differences but shared a common sequence including an epitope recognized by the monoclonal antibody 17C7. By sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), purified UspA1 exhibited a molecular weight of approximately 350,000 when unheated and a molecular weight of 100,000 after being heated for 10 min at 100°C. In contrast, purified UspA2 exhibited an apparent molecular weight of 240,000 by SDS-PAGE that did not change with the length of time of heating. Their sizes as determined by gel filtration were 1,150,000 and 830,000 for UspA1 and UspA2, respectively. Preliminary results indicate the proteins have separate functions in bacterial pathogenesis. Purified UspA1 was found to bind HEp-2 cells, and sera against UspA1, but not against UspA2, blocked binding of the O35E isolate to the HEp-2 cells. UspA1 also bound fibronectin and appears to have a role in bacterial attachment. Purified UspA2, however, did not bind fibronectin but had an affinity for vitronectin. Both proteins elicited bactericidal antibodies in mice to homologous and heterologous disease isolates. Finally, mice immunized with each of the proteins, followed by pulmonary challenge with either the homologous or a heterologous isolate, cleared the bacteria more rapidly than mock-immunized mice. These results suggest that UspA1 and UspA2 serve different virulence functions and that both are promising vaccine candidates.


1977 ◽  
Author(s):  
Christine N. Vogel ◽  
Kingdon S. Henry ◽  
Roger L. Lundblad

Our intention is to study the interaction of rabbit thrombin with antithrombin III (AT-III) in vitro and in vivo. After activation of crude prothrombin with tissue thromboplastin and CaCl2, thrombin was purified and showed two species of thrombin with molecular weights of 36,000 and 39,000 daltons as determined by sodium dodecyl sulfate discontinuous gel electrophoresis. Rabbit AT-III was purified using a heparin agarose column and had a molecular weight of 55,000 daltons. The inhibition of thrombin by AT-III was followed by fibrinogen clotting assays and an AT-III-thrombin complex was observed on gel electrophoresis. For the in vivo studies both thrombin and AT-III were radiolabelled with Na125i using the solid state lactoperoxidase method and retained 99% of the pre-iodinated specific activity. Radiolabelled thrombin and a radiolabelled AT-III-thrombin complex were injected into different rabbits. The rate of removal of both was very similar with a half-life of approximately 9 hours. When radiolabelled AT-III was injected, the half-life was approximately 60 hours. Since the disappearance rate of thrombin more closely approximates that of the preformed AT-III-thrombin complex and is clearly shorter than the turnover rate of AT-III, the possibility is raised that thrombin combines in vivo with a native inhibitor such as AT-III and may in fact be removed from the circulation as a complex rather than as a native molecule.


1979 ◽  
Author(s):  
E.R. Podack ◽  
J.G. Curd ◽  
J.H. Griffin ◽  
H.J. Müller-Eberherd

S-protein (S) is a newly discovered 80,000 MW plosma glycoprotein. It functions as an inhibitor of the membrane attack complex of complement. We now wish to report that S also functions as thrombin protecting factor in coagulation; S forms a reversible complex with thrombin which is more resistant to inactivation by antithrombin III (AT III) than thrombin alone. An S-thrombin complex and on S-throm-bin-AT III complex were formed in clotted plasma and with isolated proteins as demonstrated by two dimensional Immunoelectrophoresis. Functional studies measuring the esterolytic or clotting activity of thrombin showed that S in the presence and absence of heparin decreased the rate of inactivation of thrombin by AT III. Similar results were observed using plasma. For example, in the presence of 0.04 u/ml heparin and 1.6 u/ml thrombin, the thrombin time of plasma depleted in S was 150 sec. as opposed to 15 sec. when the plasma was reconstituted with purified S. That this effect of S was due to a decreased inactivation of thrombin by AT III was demonstrated directly by SDS-PAGE analysis of plasma containing 125l-thrombin. In the presence of S the rate of formation of the 95,000 dalton 125I-thrombin-AT III complex was markedly decreased compared to the rate of complex formation in the S-depleted plasma. These data suggest that S may modulate the interactions of thrombin and AT III.


Blood ◽  
1989 ◽  
Vol 73 (2) ◽  
pp. 490-496 ◽  
Author(s):  
PM George ◽  
P Pemberton ◽  
IC Bathurst ◽  
RW Carrell ◽  
HL Gibson ◽  
...  

Abstract Both congenital and acquired antithrombin-III (AT-III) deficiencies are amenable to replacement therapy. We describe two antithrombins produced by recombinant DNA techniques from human alpha 1-antitrypsin (alpha 1AT) cDNA in yeast. Alteration of the alpha 1AT active site, replacing methionine 358 with arginine, results in a thrombin inhibition rate similar to that of heparin-activated AT-III. Alteration of two further residues, to give a five-residue sequence identical to AT-III, does not increase this rate further. Neither antithrombin is activated by heparin; both are unglycosylated and have shorter in vivo half-lives (t1/2) than human alpha 1AT. These antithrombins should be suitable for therapeutic replacement of AT-III in cases of congenital deficiency and in conditions associated with acquired AT-III deficiency, such as disseminated intravascular coagulation.


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