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Showing papers on "Human serum albumin published in 1979"


Journal Article
TL;DR: Some results suggest the presence of more than the three binding sites for drugs on the albumin surface studied with diazepam, digitoxin and warfarin, as well as improving the binding of the radioactively labeled markers.
Abstract: Human serum albumin can be immobilized in spherical, macroporous microparticles of polyacrylamide of about 1 µm in diameter with retention of its native properties. It has been shown that diazepam, digitoxin and warfarin independently bind to albumin and can conveniently be used as markers of three separate, discrete binding sites on albumin. A simple technique has been devised by which the capacity of about 140 drugs and other compounds to affect the binding of the radioactively labeled markers has been studied. Some drugs, e.g. antirheumatic drugs of the isopropionic acid-type, some antidiabetic agents, penicillin derivatives, benzodiazepines, tryptophan, dansylsarcosine, and suiphobromophthalein efficiently displace diazepam. Other drugs, e.g., some diuretics, sulpha drugs, phenytoin, salicylic acid and butazone derivatives, azapropazoe, bilirubin, and dansylamide displace warfarin. Displacement of digitoxin is less common. In some cases the binding of the markers is improved, e.g., tamoxifen increases the binding of warfarin. Both competitive and allosteric mechanisms are responsible for the changed binding of the markers. Some results suggest the presence of more than the three binding sites for drugs on the albumin surface studied with diazepam, digitoxin and warfarin.

447 citations


Journal ArticleDOI
TL;DR: The post-translational modification appears to occur by a nonenzymatic process analogous to that responsible for glucosylation of hemoglobin A to hemoglobin AIc, i.e. through Schiff base formation and Amadori rearrangement to a ketoamine derivative.

332 citations


Journal ArticleDOI
TL;DR: It was demonstrated by light absorption spectroscopy that bilirubin forms a complex with phosphatidylcholine in diethyl ether and that an aqueous suspension of phosphatidocholine enhanced aggregation of bilirUBin.

283 citations


Journal ArticleDOI
TL;DR: The studies reported here suggest that the level of glucosylated albumin may indeed be a sensitive indicator of moderate hyperglycemia and of early glucose intolerance.
Abstract: Use of an ion exchange chromatographic method and a colorimetric method with thiobarbituric acid showed that levels of nonenzymatically glucosylated serum albumin were increased in patients with poorly controlled diabetes mellitus compared to controls. The two methods correlated well (r = 0.99) and clearly discriminated between normal and poorly controlled diabetic populations. The levels of glycosylated hemoglobin were also measured in both populations. Several patients apparently in good control based on glycosylated hemoglobin measurements were found to have increased levels of glycosylated albumin. Because albumin has a shorter circulating half-life than does the human erythrocyte, the plasma concentration of glucosylated albumin should be expected to reflect short-term control of hyperglycemia in diabetes. The studies reported here suggest that the level of glucosylated albumin may indeed be a sensitive indicator of moderate hyperglycemia and of early glucose intolerance.

272 citations


Journal Article
TL;DR: Serum amyloid P-component (protein SAP) was found to bind in vitro to isolatedAmyloid fibrils of both primary and secondary types, and C-reactive protein, which resembles protein SAP structurally but has calcium-dependent specificity for different ligands, bound significantly to only one of five different amyloids fibril preparations.
Abstract: Serum amyloid P-component (protein SAP) was found to bind in vitro to isolated amyloid fibrils of both primary and secondary types. The binding was strictly calcium-dependent, optimal uptake requiring at least 0.5 mM calcium ion. Using normal human serum as the source of protein SAP different fibril preparations became saturated with between 5--20 micrograms of SAP per mg dry weight of fibril. Isolated pure protein SAP bound in greater amounts. In control experiments SAP did not bind significantly to collagen fibrils, sheep erythrocytes, plastic shavings, or the following immobilized proteins: human kappa or lambda Bence-Jones proteins; human; rabbit or mouse IgG; human serum albumin. C-reactive protein, which resembles protein SAP structurally but has calcium-dependent specificity for different ligands, bound significantly to only one of five different amyloid fibril preparations.

250 citations


Journal ArticleDOI
TL;DR: It is suggested that the first two fatty acids bind side-by-side in an antiparallel fashion in domain III of human serum albumin in support of proposed structural models for albumin.

218 citations


Journal ArticleDOI
TL;DR: Results seem to suggest a possible role of the receptor on Dane particles (presently accepted hepatitis B virions) for polymerized albumin molecules in infecting hepatocytes both in humans and chimpanzees.

179 citations


Journal ArticleDOI
TL;DR: There is now increasing evidence that the actual number of high affinity drug-binding sites of HSA is rather small, and each of these binding sites binds several drugs of very different chemical and pharmacological properties with relative high affinity.
Abstract: Most drugs are bound to human serum albumin (HSA) via a few high affinity binding sites and several sites of much lower affinity. There is now increasing evidence that the actual number of high affinity drug-binding sites of HSA is rather small. Thus, each of these binding sites binds several drugs of very different chemical and pharmacological properties with relative high affinity. On the other hand these drug-binding sites can in some cases be very specific and even stereoselective, as demonstrated by the stereospecific binding of drugs to some of these binding sites. The discrepancy between both observations can be explained by the conformational adaptability of the HSA-binding sites.

172 citations


Journal ArticleDOI
TL;DR: The binding pattern of albumin to the strains was different from those of IgG, IgA, IgM, fibrinogen, haptoglobin, or aggregated beta 2-microglobulin and therefore seems to represent another type of bacterial-mammalian interaction with a specific albumin receptor on the surface of streptococci.
Abstract: Five gram-positive bacterial strains were selected for absorption studies of human serum samples. Strain AR1 (group A, M-type 1) and G148 (group G), with strong immunoglobulin G (IgG) binding capacities, and strain AW43 (group A, M-type 60), binding both IgA1 and IgA2, were compared with Staphylococcus aureus Cowan I and with Staphylococcus epidermidis L603. Both AR1 and G148 were capable of completely absorbing out serum IgG. In contrast, S. aureus Cowan I left a fraction unabsorbed, as expected from its known lack of IgG3 binding. Strain AW43 absorbed out all serum IgA, using a 10-microliter bacterial pellet for 20 microliter of serum. Serum IgM levels were slightly reduced by S. aureus Cowan I absorption. On the basis of the experiments, a bacterial mixture was designed consisting of S. aureus Cowan I and group A streptococcus strains AR1 and AW43, with absorption characteristics suitable for use in discriminating between early IgM and late IgG and IgA immune responses in routine serological work. A new type of bacteria-mammalian protein binding was discovered. Human serum albumin was completely absorbed out by strain G148 and to a lesser extent by strain AR1 and AW43. S. aureus Cowan I and S. epidermidis were negative. The binding capacity of G148 for albumin equalled that of Cowan I for IgG. The binding pattern of albumin to the strains was different from those of IgG, IgA, IgM, fibrinogen, haptoglobin, or aggregated beta 2-microglobulin and therefore seems to represent another type of bacterial-mammalian interaction with a specific albumin receptor on the surface of streptococci.

128 citations


Journal ArticleDOI
TL;DR: In this article, the adsorption of human serum albumin on precipitated stoichiometric hydroxyapatite Ca10(PO4)6(OH)2, /CaHA/ was followed in a wide pH range.

119 citations


Journal ArticleDOI
TL;DR: 8–Methoxypsoralen is shown to form a covalent conjugate with bovine serum albumin by UVA irradiation in the presence of 02.78 J/ds intensity, and this photoreaction appears to be completely different from the known 8–MOP photo‐cycloaddition reaction with DNA.
Abstract: — 8–Methoxypsoralen (8–MOP) is shown to form a covalent conjugate with bovine serum albumin (BSA) by UVA irradiation in the presence of 02. The photoreaction is shown to involve oxidation of 8–MOP itself as a first step, producing an oxidation product which reacts readily with protein. Thus, this photoreaction appears to be completely different from the known 8–MOP photo-cycloaddition reaction with DNA. Among several proteins studied, human serum albumin, histone type 11, RNAse A and lysozyme also undergo photoinduced addition by 8–MOP. Chemical modifications of various amino acid residues in BSA revealed tyrosine-OH as one of the reaction sites. Irradiation (12 h) with UVA at 1.78 J/ds intensity resulted in approximately 1.5 mot of 8–MOP bound to 1 mol of BSA.

Journal ArticleDOI
TL;DR: It is suggested that cholesterol and sphingomyelin enhance liposomal integrity in the presence of serum or plasma and promise to yield enhanced survival of drug-laden lipid vesicles in biological fluids in vivo.

Journal ArticleDOI
TL;DR: The excluded volume fraction for interstitial albumin was estimated in the lungs of seven mongrel dogs during steady state conditions following intravenous infusions of Ringer's solution, indicating a significant contribution by the decrease in FE to the total decrease in tissue albumin concentration as interstitial fluid volume increased.
Abstract: The excluded volume fraction for interstitial albumin (FE) was estimated in the lungs of seven mongrel dogs during steady state conditions following intravenous infusions of Ringer's solution, amounting to 0, 5, 10, and 15% of body weight (BW). We estimated the tissue blood volume with 51Cr red cells, extracellular space with 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA), and the albumin pool with 125I human serum albumin. A prenodal tracheobronchial lymphatic was cannulated for recording lymph flow (QL), total protein (CL), and albumin [CL(A)] concentrations. From these measurements, we calculated the extravascular albumin content (QA) and 99mTc-DTPA space (VI) of lung tissue samples collected at the successive volume expansions. The apparent tissue concentration of albumin (CApp = QA/VI) decreased from a control value (mean +/- SE) of 0.89 +/- 0.06 to 0.46 +/- 0.04 g/dl following the 15% BW infusion, whereas CL(A) decreased from 1.43 +/- 0.16 to 0.50 +/- 0.07 g/dl for the same volume expansion. By assuming that pulmonary lymph represented tissue fluid, we calculated a control FE of 0.38 +/- 0.02 using the equation, FE = 1 - [CApp/CL(A)]. FE decreased following successive infusions to 0.28 +/- 0.03, 0.16 +/- 0.02, and 0.10 +/- 0.02. These data indicate a significant contribution by the decrease in FE to the total decrease in tissue albumin concentration as interstitial fluid volume increased. Somewhat unexpectedly, the mean steady state QL increased by only 2.1-fold following the 5% BW expansion, but did not further increase following subsequent volume expansions. This has been attributed to a nonlinear interstitial compliance, sequestration of interstitial fluid, or possible deterioration of the experimental preparation.

Journal ArticleDOI
TL;DR: Strong evidence was presented that only one tyrosine residue, which reacts faster with tetranitromethane than all others, is mainly involved in the specific indole and benzodiazepine binding site of human serum albumin.

Journal Article
TL;DR: In this paper, the authors used a reaction developed by Krejcarek and Tucker, in which DTPA is coupled to proteins by the formation of an amide bond, and they studied the efficiency of the reaction of HSA with the mixed acid anhydride of the quarternary triethyl ammonium salt of DTPA and butyl formate.
Abstract: Because of the high stability constant of gallium transferrin, the formation of a protein that will be stable in vivo and labeled with gallium-68 (a positron emitter) requires preliminary coupling of a strong chelating group to the protein. In the present study, we have used a reaction developed by Krejcarek and Tucker, in which DTPA is coupled to proteins by the formation of an amide bond. Using human serum albumin (HSA) as a model, we have studied the efficiency of the reaction of HSA with the mixed acid anhydride of the quarternary triethyl ammonium salt of DTPA and butyl formate, as a function of the ratio of albumin to DTPA. After purification of the DTPA-labeled HSA, it is possible to prepare Ga-68-labeled albumin in high yield by chelation of the Ga-68 with the DTPA-labeled protein. In vitro and in vivo stability studies showed that the labeled protein was stable over a period of several hours. The same type of bifunctional chelate has been used to attach Ga-68 to HSA microspheres.

Journal ArticleDOI
TL;DR: A small contamination of transferrin in the human serum albumin preparations used was shown to be responsible for their growth‐supporting effect, while no need for the presence of albumin itself could be demonstrated.
Abstract: Activation of human T cells by mitogens was compared in cultures containing serum, human serum albumin or purified human transferrin as growth support. The mitogenic effect of the lectins leucoagglutinin, concanavalin A and Wistaria floribunda agglutinin was measured as incorporation of [3H]thymidine into the cellular DNA of the lymphocytes. Three different preparations of transferrin were all able to fully substitute serum or serum albumin as growth promotors, when present at concentrations of 10 microgram/ml or more. A small contamination of transferrin in the human serum albumin preparations used was shown to be responsible for their growth-supporting effect, while no need for the presence of albumin itself could be demonstrated.

Journal ArticleDOI
TL;DR: The bulk of radioactivity incorporated into high-density lipoprotein by photoaffinity labelling of whole serum was found to have been associated with the lipids, and the interaction of taurocholate with high- density lipop protein has been confirmed by density gradient centrifugation using 14C-labelled taurcholate.
Abstract: 1. Photoaffinity labelling of human serum albumin with the sodium salts of (3 beta-azido-7 alpha,12 alpha-dihydroxy-5 beta-cholan-24-oyl)-2-amino[2(-3)H (N)]ethanesulfonic acid, (7,7-azo-3 alpha,12 alpha-dihydroxy-5 beta-cholan-24-oyl)-2-amino[2(-3)H (N)]ethanesulfonic acid and (11 zeta-azido-12-oxo-3 alpha,7 alpha-dihydroxy-5 beta-cholan-24-oyl)-2-amino[2(-3)H (N)]ethanesulfonic acid resulted, in each case, in a considerable covalent incorporation of radioactivity into the protein. 2. Photoaffinity labelling of whole serum, obtained from fasting test persons, revealed with all three photolabile derivatives of taurocholate at the physiological concentration of 2.1 microM the incorporation of radioactivity not only into albumin but also into high-density lipoprotein, as demonstrated by density gradient centrifugation and by immunological characterization. 3. The bulk of radioactivity incorporated into high-density lipoprotein by photoaffinity labelling of whole serum was found to have been associated with the lipids. Only 10-20% of the label was covalently bound to apolipoproteins, predominantly to the apolipoproteins A-I and A-II. 4. The interaction of taurocholate with high-density lipoprotein has been confirmed by density gradient centrifugation using 14C-labelled taurcholate. It is assumed that the interaction of taurocholate with high-density lipoprotein is physiologically of significance.

Journal ArticleDOI
TL;DR: Findings give support to the assumption that the binding site for warfarin on the albumin molecule is affected by the neutral-to-base transition in the protein.

Journal ArticleDOI
TL;DR: This reactive tyrosine residue appears to be located in a primary binding site for small apolar anions and to be closely associated with several cationic groups.

Journal ArticleDOI
TL;DR: The chemical structures proposed by these observations are similar to those of classical hapten derivatives and suggest that such derivatives may be immunogenic and/or allergenic in some workers exposed to the vapors of these reagents.

Journal ArticleDOI
TL;DR: The anaphylactoid reactions developing after PP or HSA infusion result from a non‐specific reaction to protein aggregates and in some cases possibly from a specific immune response to the caprylate‐modified HSA.
Abstract: Six patients suffering from anaphylactoid reactions after infusion of pasteurized plasma (PP) or human serum albumin (HSA) were investigated. Clinical symptoms ranged from urticaria and hypotension to cardiac arrest. Immunoglobulin levels, especially of IgA, were normal, as were concentrations of complement factors C3, C4 and factor B. In skin and lymphocyte transformation tests patients, with the exception of one severely allergic to protein, did not react to the monomeric pure HSA. Five out of six patients reacted against HSA aggregates and three patients to the HSA modified by caprylate added as stabilizer during commercial HSA production. It is concluded that the anaphylactoid reactions developing after PP or HSA infusion result from a non-specific reaction to protein aggregates and in some cases possibly from a specific immune response to the caprylate-modified HSA.

Journal ArticleDOI
TL;DR: In this article, a size exclusion chromatographic method for measuring ligand-macromolecule binding parameters is described, which allows the determination of the concentrations of constituents in equilibrium and is specially useful for characterizing ligandprotein binding under conditions that can be compared with physiological conditions.

Journal Article
TL;DR: The identification of the lone tryptophan residue as a part of the warfarin binding site of human serum albumin is a significant step forward in localizing this important drug binding site.
Abstract: The interaction of warfarin and dicoumarol with tryptophan- and tyrosine-modified human serum albumin derivatives was investigated by equilibrium dialysis and circular dichroism measurements. The binding of warfarin to its specific high-affinity binding site is strongly reduced after the modification of the lone tryptophan residue of human serum albumin with three different reagents, while the modification of tyrosine residues has nearly no effect on the binding of warfarin to this site. It is concluded that the lone tryptophan residue is part of the warfarin binding site which is clearly separated from the specific indole and benzodiazepine binding site. Evidence is presented that dicoumarol interacts with the warfarin as well as the indole and benzodiazepine binding site of the human serum albumin molecule. A highly reactive tyrosine residue specifically involved in the indole and benzodiazepine binding site seems to be important for the dicoumarol binding, too. Its nitration with tetranitromethane differently affects the four induced circular dichroism bands of dicoumarol bound to human serum albumin. This effect has been qualitatively and quantitatively characterized by the resolution of the induced circular dichroism spectrum of dicoumarol bound to human serum albumin into the Gaussian component bands using a computer program. The identification of the lone tryptophan residue as a part of the warfarin binding site of human serum albumin is a significant step forward in localizing this important drug binding site.

Journal ArticleDOI
TL;DR: A radioimmunoassay for albumin-binding sites associated with hepatitis B surface antigen (HBsAg) is described and the quantity of HBsAg attached to the beads, determined by measuring the amount of 125I-labeled anti-HBs adsorbed during a subsequent incubation step, was related to the presence of HBeAg.
Abstract: A radioimmunoassay for albumin-binding sites associated with hepatitis B surface antigen (HBsAg) is described. Polystyrene beads coated with glutaraldehyde-polymerized human serum albumin were incubat

Journal ArticleDOI
TL;DR: Combining circular dichroism and gel filtration method in studying the binding of chiral ((S)/R)- 1 and prochiral benzodiazepines to human serum albumin (HSA) revealed that both enantiomers of 1 are bound by HSA with different affinities.

Journal ArticleDOI
TL;DR: Results show that binding to HSA is 97 per cent at therapeutic levels and free fatty acids (FFA) decrease indomethacin binding in human serum albumin (HSA), and indometHacin markedly decreases warfarin binding.

Journal ArticleDOI
TL;DR: The reactivity of diluted human serum with p-nitrophenylacetate was found to be one-third to one-half of that expected for its content of serum albumin, but as in vitro, it could be completely inhibited by small amounts of decanoate.


Journal ArticleDOI
TL;DR: Results show that, as the concentration of albumin increases, the binding of all three drugs decreases, but this phenomenon does not appear to be due to the presence of endogenous-competing ligands in serum or crystalline albumin preparations.

Journal ArticleDOI
TL;DR: It is shown that HSA can be tightly bound to Amberlite XAD-7 without the use of chemical coupling agents and the adsorption conforms to Langmuir's isotherm.
Abstract: Platelets adhere to most foreign surfaces. As a result, polymers and albumin have been suggested as possible coatings to improve the blood compatibility of such surfaces. Amberlite XAD-7 has a high affinity for human serum albumin (HSA) and several protein-bound toxic metabolites. In the present study it is shown that HSA can be tightly bound to Amberlite XAD-7 without the use of chemical coupling agents. Optimal binding was achieved at pH 5.0 and the adsorption conforms to Langmuir's isotherm. Theoretical analysis of data and absence of a residual surface coating visible with scanning electron microscopy suggest a monolayer of albumin. The amount of HSA eluted from the resin under severe flow conditions was negligible (approximately 1%). Furthermore, in stirred batch studies with human plasma, the HSA coating did not decrease the adsorptive capacity of XAD-7 for bile acids and bilirubin.