DISCREPANCIES IN PLASMA LH ACTIVITIES AS MEASURED BY RADIOIMMUNOASSAY AND AN IN VITRO BIOASSAY

1974 ◽  
Vol 77 (4) ◽  
pp. 672-685 ◽  
Author(s):  
M. H. Qazi ◽  
P. Romaní ◽  
E. Diczfalusy
Keyword(s):  
Molecular Weight ◽  
Biological Activity ◽  
Gel Filtration ◽  
Biologically Active ◽  
Plasma Samples ◽  
Elution Volume ◽  
Immunological Activity ◽  
Molecular Weight Range ◽  
Weight Range

ABSTRACT Using a highly sensitive in vitro bioassay system, luteinizing hormone activity has been measured in parallel with radioimmunoassays in postmenopausal plasma and plasma obtained from women in various phases of the menstrual cycle (follicular, mid-cycle, luteal). Biological and immunological activities were measured directly in plasma samples without any chemical manipulation. The biological activity (B) was always higher than the immunological activity (I); the B/I ratio varied from 2.1 to 14.0. Gel filtration of pooled plasma samples through Sephadex G-100 revealed major discrepancies in each physiological state when immunological and biological activities were measured in each fraction. The biological activity was eluted as a single peak behind the elution volume of bovine serum albumin, but in front of the elution volume of chymotrypsinogen. It was invariably preceded by a small hump. The immunological activity was spread all over the chromatogram. Areas of immunological activity without any biological activity were located on either side of the biologically active fractions, both in the high molecular weight range (including the void volume) and in the low molecular weight range. The biological LH activity recovered following fractionation on Sephadex G-100 was in close agreement with that loaded, whereas the immunological activity recovered following gel filtration exceeded the loaded activity by a factor of 6–8. In the various physiological states, 11 to 44 % of the total immunological activity recovered was not associated with any biological activity. Furthermore, there was a marked variation in the ratio of biological to immunological activities of those fractions which contained biological activity. It is suggested that the specificity of current RIA methods could be improved significantly by preparing antisera which react only with biologically active LH species.

Isolation of the γc-globulin of bovine cerebrospinal fluid

1968 ◽  
Vol 46 (3) ◽  
pp. 273-276
Author(s):  
Catherine F. C. MacPherson ◽  
François Feldmuller
Keyword(s):  
Molecular Weight ◽  
Cerebrospinal Fluid ◽  
Gel Filtration ◽  
Globulin Fraction ◽  
Elution Volume ◽  
Immunological Activity ◽  
Immunochemical Method ◽  
Milk Whey ◽  
Preliminary Filtration ◽  
Gel Diffusion

The γc-globulin of bovine cerebrospinal fluid (CSF) was isolated in immunologically pure form from the globulin fraction of CSF or milk whey by gel filtration on Sephadex G-75. The globulin fraction was obtained by precipitation with sodium or ammonium sulfate rather than by DEAE chromatography because salt precipitation resulted in greater yields of the γc-globulin. When the protein was isolated from bovine colostral whey, about 90% of the immunoglobulin G (IgG) globulin was removed by a preliminary filtration of the whey on Sephadex G-75. The fraction containing the γc-globulin admixed with IgG globulin was then re-chromatographed on Sephadex G-75 to remove the IgG globulin. On gel filtration through a column of Sephadex G-75 that had been calibrated with proteins of known molecular weight, the elution volume of the γc-globulin corresponded to a molecular weight of 30 000. Different lots of γc-globulin that contained no detectable impurities by gel-diffusion tests were compared on a weight basis by a quantitative immunochemical method, and were found to have equal immunological activity.

scholarly journals Polymeric C-terminal cross-linked material from type-I collagen. A modified method for purification, anomalous behaviour on gel filtration, molecular weight estimation, carbohydrate content and lipid content

1980 ◽  
Vol 189 (1) ◽  
pp. 111-124 ◽  
Author(s):  
N D Light ◽  
A J Bailey
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Type I Collagen ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Type I ◽  
Molecular Weight Range ◽  
Carbohydrate Analysis ◽  
Weight Range

Polymeric cross-linked C-terminal peptide material (poly-alpha 1CB6) from mature bovine tendon type-I collagen was prepared and purified by a modification of the method previously described [Light & Bailey (1980) Biochem. J. 185, 373-381]. Poly-alpha 1CB6 was shown to exhibit concentration-dependent aggregation effects on gel filtration due to interaction with a filtration medium. The material had an amino acid content that was very similar to a mixture of alpha 1CB6 and alpha 1CB5. The material was shown to be polydisperse with a mol.wt. range of 50 000-350 000, but chromatographic fractions were relatively homogeneous over this molecular weight range with respect to amino-acid composition. The heterogeneity of the material was not due to incomplete CNBr peptide cleavage, as poly-alpha 1CB6 did not contain detectable quantities of methionine. The material showed no discrete bands on sodium dodecyl sulphate/polyacrylamide-gel electrophoresis but gave a constant blue stain throughout the molecular weight range described above. Lipid analysis showed that the partially purified material contained elevated levels of stearate when compared to the crude CNBr-digested starting material. This may indicate the specific association of a stearic-acid-rich lipid with the peptide material. On carbohydrate analysis poly-alpha 1CB6 was shown to contain only galactose and glucose at levels of 0.72 and 0.28% respectively. The carbohydrate and amino acid analyses indicated that (alpha 1CB6)2-(alpha 1CB5)1 may be the basic cross-linked structural unit of poly-alpha 1CB6)2-(alpha 1CB5)1 units, although the carbohydrate analysis indicated that the higher molecular weight oligomers may be enriched in alpha 1CB6.

INFLUENCE OF THE PURITY OF THE IODINATED TRACER ON THE SPECIFICITY OF THE RADIOIMMUNOASSAY OF HUMAN LUTEINIZING HORMONE

1978 ◽  
Vol 89 (3) ◽  
pp. 506-520 ◽  
Author(s):  
H. Suginami ◽  
D. M. Robertson ◽  
E. Diczfalusy
Keyword(s):  
High Resolution ◽  
Luteinizing Hormone ◽  
Gel Filtration ◽  
Cross Reactivity ◽  
Biologically Active ◽  
Immunological Activity ◽  
Subunit A ◽  
Adsorption Step ◽  
Reference Preparation

ABSTRACT Human luteinizing hormone (HLH) iodinated with 125I by the use of a lactoperoxidase method, was fractionated by either cellulose adsorption, gel filtration or by the combination of these methods. The products of iodination were characterized by their in vitro biological LH activity and by their binding profiles with antisera to HLH, HLHα and HLHβ subunits. Several radioactive components were obtained after gel filtration with or without an initial cellulose adsorption step. One of these fractions was identified as biologically active HLH and another as the HLHα subunit. Radioimmunoassay studies were conducted with different iodinated fractions as tracers, using three well defined and widely available antisera to HLH. The standard used was the HLH International Reference Preparation for immunoassay (68/40). Cross-reactivity was examined with several purified pituitary preparations, such as HFSH, HTSH, HLHα and HLHβ subunit. A significantly higher cross-reactivity with HLHα, HFSH and HTSH was obtained with the [125I]HLHα fraction as tracer than with biologically active [125I]HLH. Furthermore, in the radioimmunoassay of HLH preparations of varying purity, significantly higher estimates of immunological activity were obtained with the [125I]HLHα tracer than with the biologically active [125I]HLH. It is concluded that the presence of [125I]HLHα in the [125I]HLH tracer can result in serious overestimates of the immunological activity in the measurement of LH. Therefore [125I]HLHα should be separated from [125I]HLH prior to radioimmunoassay. Many of the fractionation methods commonly used (cellulose adsorption and short column gel filtration systems) are inadequate for this purpose. However, an adequate separation can be achieved by the use of high resolution gel filtration systems.

Low Molecular Weight Heparin Is Responsible for the Anti-Xa Activity of Desmin 370

1996 ◽  
Vol 75 (02) ◽  
pp. 286-291 ◽  
Author(s):  
David Brieger ◽  
Joan Dawes
Keyword(s):  
Molecular Weight ◽  
Low Molecular Weight Heparin ◽  
Anticoagulant Activity ◽  
Factor Xa ◽  
Biologically Active ◽  
Low Molecular Weight ◽  
Dermatan Sulphate ◽  
Molecular Weight Range ◽  
Sulphated Glycosaminoglycan

SummaryDermatan sulphate does not catalyse the inactivation of factor Xa. However, the low molecular weight (LMW) dermatan sulphate Desmin 370 has been shown to generate circulating anti-Xa activity following administration to humans. Using a single batch of Desmin 370, we measured 3 U/mg of anti-Xa activity by amidolytic assay in vitro. The material responsible for this activity had a lower molecular weight range (6000 and 1800 Da) than Desmin 370 and was more highly sulphated than the bulk of the drug. Heparinase digestion of Desmin 370 eliminated 90% of the in vitro anti-Xa activity without significantly interfering with its ability to potentiate inactivation of thrombin by HCII, suggesting that the anti-Xa activity is not due to dermatan sulphate and is probably heparin. When 125I-labelled Desmin 370 together with 40 mg/kg carrier drug was administered intravenously to a rabbit, anti-Xa activity was readily detectable in the plasma for up to 10 h and had a longer half-life than the sulphated radiolabel. Most of this anticoagulant activity was recovered from the plasma by Polybrene affinity chromatography and was probably a sulphated glycosaminoglycan. Administration of the heparinase-digested drug to a rabbit resulted in 70% less anti-Xa activity than the undigested drug. We conclude that Desmin 370 contains detectable quantities of biologically active low molecular weight heparin, which is responsible for persistent anti-Xa activity following intravenous administration.

scholarly journals STUDIES ON THE PATHOGENESIS OF FEVER

1968 ◽  
Vol 127 (2) ◽  
pp. 341-357 ◽  
Author(s):  
Marilyn Sue Kozak ◽  
Helmut H. Hahn ◽  
William J. Lennarz ◽  
W. Barry Wood
Keyword(s):  
Molecular Weight ◽  
Biological Activity ◽  
Active Material ◽  
Gel Filtration ◽  
Chemical Properties ◽  
Disc Electrophoresis ◽  
Polyacrylamide Gel ◽  
Sulfhydryl Groups ◽  
Biologically Active ◽  
Exhaustive Extraction

Small quantities of highly purified granulocytic pyrogen have been separated from contaminating proteins by disc electrophoresis in polyacrylamide gel. The biologically active material thus isolated was shown to be electrophoretically homogeneous at pH 9 and pH 3.8. Earlier work on the chemical properties of the pyrogen molecule has been extended to include: (a) estimation of its molecular weight by gel filtration; (b) demonstration of free sulfhydryl groups essential for its biological activity; and (c) evidence that it is not inactivated by exhaustive extraction with ethanolether or n-heptane.

scholarly journals Nuclear matrix of HeLa S3 cells. Polypeptide composition during adenovirus infection and in phases of the cell cycle.

1977 ◽  
Vol 72 (1) ◽  
pp. 194-208 ◽  
Author(s):  
L D Hodge ◽  
P Mancini ◽  
F M Davis ◽  
P Heywood
Keyword(s):  
Cell Cycle ◽  
Molecular Weight ◽  
Nuclear Matrix ◽  
Apparent Molecular Weight ◽  
Molecular Weight Range ◽  
Weight Range ◽  
Molecular Weights ◽  
Liver Nuclei ◽  
Hela S3 ◽  
Biochemical Analyses

A subnuclear fraction has been isolated from HeLa S3 nuclei after treatment with high salt buffer, deoxyribonuclease, and dithiothreitol. This fraction retains the approximate size and shape of nuclei and resembles the nuclear matrix recently isolated from rat liver nuclei. Ultrastructural and biochemical analyses indicate that this structure consists of nonmembranous elements as well as some membranous elements. Its chemical composition is 87% protein, 12% phospholipid, 1% DNA, and 0.1% RNA by weight. The protein constituents are resolved in SDS-polyacrylamide slab gels into 30-35 distinguishable bands in the apparent molecular weight range of 14,000 - 200,000 with major peptides at 14,000 - 18,000 and 45,000 - 75,000. Analysis of newly synthesized polypeptides by cylindrical gel electrophoresis reveals another cluster in the 90,000-130,000 molecular weight range. Infection with adenovirus results in an altered polypeptide profile. Additional polypeptides with apparent molecular weights of 21,000, 23,000, and 92,000 become major components by 22 h after infection. Concomitantly, some peptides in the 45,000-75,000 mol wt range become less prominent. In synchronized cells the relative staining capacity of the six bands in the 45,000-75,000 mol wt range changes during the cell cycle. Synthesis of at least some matrix polypeptides occures in all phases of the cell cycle, although there is decreased synthesis in late S/G2. In the absence of protein synthesis after cell division, at least some polypeptides in the 45,000-75,000 mol wt range survive nuclear dispersal and subsequent reformation during mitosis. The possible significance of this subnuclear structure with regard to structure-function relationships within the nucleus during virus replication and during the life cycle of the cell is discussed.

HEMODIALYSIS OF THE RAT

1966 ◽  
Vol 44 (5) ◽  
pp. 849-859 ◽  
Author(s):  
Sumner M. Robinson ◽  
David A. Hurwitz ◽  
Robert Louis-Ferdinand ◽  
William F. Blatt
Keyword(s):  
Molecular Weight ◽  
Gel Filtration ◽  
Low Molecular Weight

A technique is described for hemodialysis of either anesthetized or non-restrained rats. In the apparatus the dialysis plates of an autoanalyzer system are used with only minor modification. The efficiency of this method has been evaluated with regard to the clearance of saccharides, both in vitro and in vivo, as well as the extraction of nitrogenous low molecular weight moieties from circulating blood. Approximately 50% of the dialyzable material was obtained in a 1-hour dialysis. Further fractionation of the dialyzate was accomplished by gel filtration (Sephadex G-25).

Uremic Neurotoxin in the Middle Molecular Weight Range

1980 ◽  
Vol 4 (2) ◽  
pp. 116-120 ◽  
Author(s):  
N.K. Man ◽  
G. Cueille ◽  
J. Zingraff ◽  
J. Boudet ◽  
A. Sausse ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Molecular Weight Range ◽  
Weight Range

scholarly journals Isolation and Characterization of Two Proteins fromMoraxella catarrhalis That Bear a Common Epitope

1998 ◽  
Vol 66 (9) ◽  
pp. 4374-4381 ◽  
Author(s):  
John C. McMichael ◽  
Michael J. Fiske ◽  
Ross A. Fredenburg ◽  
Deb N. Chakravarti ◽  
Karl R. VanDerMeid ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Bacterial Attachment ◽  
Vaccine Candidates ◽  
Isolation And Characterization ◽  
Sds Page

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.

scholarly journals Characterization of proteins from the cytoskeleton of Giardia lamblia

1983 ◽  
Vol 59 (1) ◽  
pp. 81-103 ◽  
Author(s):  
R. Crossley ◽  
D.V. Holberton
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulphate ◽  
Giardia Lamblia ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Molecular Size ◽  
Molecular Weights

Proteins from the axonemes and disc cytoskeleton of Giardia lamblia have been examined by sodium dodecyl sulphate/polyacrylamide gel electrophoresis. In addition to tubulin and the 30 X 10(3) molecular weight disc protein, at least 18 minor components copurify with the two major proteins in Triton-insoluble structures. The most prominent minor bands have the apparent molecular weights of 110 X 10(3), 95 X 10(3) and 81 X 10(3). Protein of 30 X 10(3) molecular weight accounts for about 20% of organelle protein on gels. In continuous 25 mM-Tris-glycine buffer it migrates mostly as a close-spaced doublet of polypeptides, which are here given the name giardins. Giardia tubulin and giardin have been purified by gel filtration chromatography in the presence of sodium dodecyl sulphate. Well-separated fractions were obtained that could be further characterized. Both proteins are heterogeneous when examined by isoelectric focusing. Five tubulin chains were detected by PAGE Blue 83 dye-binding after focusing in a broad-range ampholyte gel. Giardin is slightly less acidic than tubulin. On gels it splits into four major and four minor chains with isoelectric points in the pI range from 5.8 to 6.2. The amino acid composition of the giardin fraction has been determined, and compared to Giardia tubulin and a rat brain tubulin standard. Giardins are rich in helix-forming residues, particularly leucine. They have a low content of proline and glycine; therefore they may have extensive alpha-helical regions and be rod-shaped. As integral proteins of disc microribbons, giardins in vivo associate closely with tubulin. The properties of giardins indicate that in a number of respects - molecular size, charge, stoichiometry - their structural interaction with tubulin assemblies will be different from other tubulin-accessory protein copolymers studied in vitro.

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