Disease relevance of AGP

• Human AGP prevented hemolysis induced by hypotonic phosphate buffer solution [1].
• A good correlation of disease activity, as measured by serum alpha 1-acid glycoprotein concentrations, and immunoglobulin G and immunoglobulin A antibody titers against certain cow's milk proteins could be demonstrated in Crohn's disease, but not ulcerative colitis [2].
• The protection conferred by alpha 1-AGP and alpha 1-AT is presumably indirect, since these proteins did not inhibit TNF/actinomycin D-induced apoptosis in the hepatoma cell lines HepG2 and BWTG3 [3].
• Effects of localized Pasteurella haemolytica infection on erythromycin-binding properties of bovine alpha-1-acid glycoprotein, albumin, serum, and tissue chamber fluids [4].
• Reduction of the in vitro activity of A77003, an inhibitor of human immunodeficiency virus protease, by human serum alpha 1 acid glycoprotein [5].

High impact information on AGP

• The mechanism of chiral recognition for DDP and DLP by AGP is discussed and should be equally applicable to other dansyl-derivative amino acid enantiomers [6].
• Detailed studies of the protein binding of KNI-272 suggest that in human plasma binding occurs predominantly to alpha 1-acid glycoprotein and that KNI-272 is probably extensively (approximately 98 to 99%) protein bound at concentrations likely to be achieved in the circulation [7].
• The in vitro erythromycin-binding properties of bovine alpha-1-acid glycoprotein (AAG) and albumin were studied by using equilibrium dialysis [4].
• The unnatural FPP analogue 8-anilinogeranyl diphosphate (AGPP, 3b) is an effective alternative substrate for mammalian FTase [8].
• Decreased elimination of drug in the presence of alpha-1-acid glycoprotein is related to a reduced hepatocyte uptake [9].

Biological context of AGP

• AGP is an immunocalin, a binding protein that can also exert several immunomodulatory functions [10].
• The goal of this study was to classify and identify the ligand binding sites on alpha(1)-acid glycoprotein (AGP) from 3 species, in order to understand species differences with respect to both ligand binding properties and ligand interaction on protein binding [11].
• Protein binding kinetics of lincomycin (LM) and clindamycin (CM) were studied using plasma, albumin and alpha 1-acid glycoprotein (AGP) derived from humans, dogs, cattle and sheep [12].
• These results suggest that an increase in the AGP content of serum above the normal value found under pathological conditions facilitates the passage of erythrocytes through capillaries, stabilizes erythrocyte membranes and protects against oxidative stress, all of which are favorable for microcirculation [1].
• We found that both bovine alpha 1-AGP and human alpha 1-AT also inhibited specifically the induction of apoptosis of hepatocytes by TNF/ galactosamine in vivo [3].

Anatomical context of AGP

• Alpha1-acid glycoprotein (AGP) is an immunomodulatory protein expressed by hepatocytes in response to the systemic reaction that follows tissue damage caused by inflammation, infection or trauma [13].
• Blood serum values for cortisol and alpha1-acid glycoprotein (AGP) exhibited few treatment differences [14].
• Bovine AGP was detected by Western blotting in all the samples analysed, and could be quantified in colostrum at 162 (+/- 63.7) microg/mL and 114.5 (+/- 67.8) microg/mL during the first 12 h and 24 h respectively [13].
• In order to investigate the origin of AGP in bovine milk, a search for mRNA was carried out in somatic cells and mammary gland tissue: mRNA expression of the boAGP gene was detected in mammary gland tissue, but not in somatic cells [13].
• The effects of human AGP on the oxidative changes in erythrocytes exposed to oxygen radicals were investigated [1].

Associations of AGP with chemical compounds

• The purity of three AGP glycoforms isolated was assessed by hydroxyapatite high-performance liquid chromatography (HPLC), gel-permeation chromatography and SDS-PAGE [15].
• These results suggest that the protective effect of AGP is likely mediated by its sialic acid terminal groups [10].
• Moreover, dog and bovine AGP each have a basic ligand binding site and a steroid hormone binding site, which significantly overlap and affect each other [11].
• The lack of detection of specific binding for LM in cattle and sheep and for CM in sheep plasma could be attributable to a higher Kd and lower plasma AGP concentration compared with other species [12].
• These characteristics of human, dog and bovine AGP were examined using the basic ligands chlorpromazine and auramine O, the acidic ligand acenocoumarin, and the steroid hormone progesterone [11].

Regulatory relationships of AGP

• However, human AGP may promote microcirculation and antioxidant activity compared with HSA [1].

Other interactions of AGP

• Vibrational circular dichroism (VCD) spectra for the glycoproteins alpha1-acid glycoprotein (AGP) and bovine submaxillary mucin (BSM), have been measured in D2O solutions and for the films prepared from aqueous (H2O) buffer solutions in the 1800 to 900 cm(-1) region [16].
• Automated high-performance liquid chromatography was used to analyse dansylhydrazine derivatives of neutral sugars in unfractionated acid hydrolysates of four well-characterized glycoproteins: fetuin, ovalbumin, alpha-1-acid glycoprotein and bovine submaxillary mucin [17].
• Treatment of asialofetuin with endo--alpha--N--acetylgalactosaminidase eliminated its affinity for the lectin column, and other proteins known to contain only N-linked oligosaccharides such as ovalbumin, transferrin, and alpha 1-acid glycoprotein were not retained by the lectin [18].
• Haptoglobin appearance in serum was not associated with the increase of alpha 1-acid glycoprotein (a marker for inflammation) [19].
• Other serum proteins that have been proposed to reduce endothelial permeability, alpha 1-acid glycoprotein (0.035-0.14 g/100 ml) and fibronectin (5 mg/100 ml), did not decrease 125I-albumin permeability from DMEM values [20].

Analytical, diagnostic and therapeutic context of AGP

• One was identified as AGP from its mobility on SDS-PAGE, demonstrating the potential of this assay even with crude materials [21].
• The presence of AGP in bovine milk was confirmed by the internal sequence analysis performed following purification to homogeneity of the protein from milk [13].
• CAP is extracted in acetonitrile and purified by affinity chromatography on an alpha-1-acid glycoprotein (AAG) column, then is identified and determined by ion-trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) analysis in the negative ion mode [22].
• These results suggest that alpha 1-acid glycoprotein, which interacts specifically with debromoaplysiatoxin, contained in bovine serum must have masked the in vitro properties of the tumor promoter in the biological assay systems [23].
• Determination of alpha 1AG was made by use of a single radial immunodiffusion method [24].

References