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Selective Antibodies (selective + antibody)
Selected AbstractsSelective antibodies to methadone enantiomers: Synthesis of (R)- and (R,S)-methadone conjugates and determination by an immunoenzymatic method in human serumCHIRALITY, Issue 4 2001Nassima Chikhi-Chorfi Abstract Selective antibodies to (R)-methadone (Mtd) and to its racemate were produced in rabbits by immunization with conjugates of (R)- or (R,S)-hemisuccinyl-methadol-bovine serum albumin, respectively. A hapten was first prepared by reduction of (R)- or (R,S)-Mtd with sodium borohydride, followed by esterification with succinic anhydride. The conjugation of hapten with albumin was achieved by the mixed anhydride method. After immunization of rabbits, the titers and specificity of each antibody were determined by ELISA. The antibodies obtained were tested with (R)-, (S)-, (R,S)-Mtd, its major metabolite (EDDP), and some drugs of abuse (morphine, codeine, cocaine). The sensitivities of antibodies to (R)- and (R,S)-Mtd were about 1 and 2 ng/ml, respectively. Selective (R)-antibodies recognized (R)-Mtd about 40 times more avidly than the (S)-isomer, while an antiserum against (R,S)-Mtd recognized (R)- and (S)-isomers to about the same degree. Both selective antibodies showed little interference (about 0.5%) with EDDP metabolite and no crossreactivity with morphine, codeine, and cocaine. These two selective antibodies were used to develop an immunoenzymatic method (ELISA) for the determination of (R)- and (R,S)-Mtd in serum samples of patients under maintenance treatment for narcotic addiction. Chirality 13:187,192, 2001. © 2001 Wiley-Liss, Inc. [source] Adipocyte-derived angiopoietin-1 supports neurite outgrowth and synaptogenesis of sensory neuronsJOURNAL OF NEUROSCIENCE RESEARCH, Issue 7 2006Joanna Kosacka Abstract Sensory and sympathetic innervation of the white fat tissue (WAT) contributes to lipolysis. In addition, both fiber types adapt in density to weight gain and loss. Because these findings are indicative for a tight control of nerve fiber plasticity by adipokines, we tested whether adipocytes control neurite growth of sensory neurons through angiopoietin-1 (Ang-1). We further considered initial hints that Ang-1-induced neuritogenesis involves transactivation of the high-affinity nerve growth factor (NGF) receptor trkA. Coculturing dorsal root ganglion (DRG) cells with 3T3-L1 adipocytes supported neurite outgrowth. These neurotrophic effects were associated with the increased expression of Ang-1 (presumably in adipocytes) as well as of trkA. The effects were abolished upon inactivating Ang-1 in culture with selective antibodies. Likewise, neurite outgrowth was impaired in the presence of inactivating NGF antibodies as well as upon inhibition of the NGF high-affinity trkA receptor with the antagonist K252a, indicating a tight cooperation of Ang-1 and NGF in the control of neuritogenesis. DRG-adipipocyte cocultures were further used to establish whether sensory neurons would form synaptic contacts with adipocytes. Electron microscopy demonstrated that cultured sensory neurons develop predominantly neuroneuronal synapses but seem to affect adipocytes by synapses en passant. Comparably to the case for neuritogenesis, expression of the presynaptic protein synaptophysin as well of the postsynaptic protein PSD-95 correlated with Ang-1 levels in culture. It is concluded that adipocyte-secreted Ang-1 supports neurite outgrowth, which is involved in synaptogenesis. The novel function of Ang-1 appears to play a physiological role in WAT plasticity. © 2006 Wiley-Liss, Inc. [source] Enantioselective Proteins: Selection, Binding Studies and Molecular Modeling of Antibodies with Affinity towards Hydrophobic BINOL DerivativesCHEMBIOCHEM, Issue 16 2007Brian Schou Rasmussen Dr. Abstract In this paper, the initial steps towards the design of novel artificial metalloenzymes that exploit proteins as a second coordination sphere for traditional metal,ligand catalysis are described. Phage display was employed to select and study antibody fragments capable of recognizing hydrophobic BINOL derivatives designed to mimic BINAP, a widely used ligand in asymmetric metal-catalyzed reactions. The binding affinities of the selected antibodies towards a series of haptens were evaluated by using ELISA assays. A homology model of one of the most selective antibodies was constructed, and a computer-assisted ligand-docking study was carried out to elucidate the binding of the hapten. It was shown that, due to the hydrophobic nature of the haptens, a higher level of theoretical treatment was required to identify the correct binding modes. A small selection of the antibodies was found to discriminate between enantiomers and small structural modifications of the BINOL derivatives. The selectivities arise from hydrophobic interactions, and we propose that the identified set of antibodies provides a foundation for a novel route to artificial metalloenzymes. [source] Selective antibodies to methadone enantiomers: Synthesis of (R)- and (R,S)-methadone conjugates and determination by an immunoenzymatic method in human serumCHIRALITY, Issue 4 2001Nassima Chikhi-Chorfi Abstract Selective antibodies to (R)-methadone (Mtd) and to its racemate were produced in rabbits by immunization with conjugates of (R)- or (R,S)-hemisuccinyl-methadol-bovine serum albumin, respectively. A hapten was first prepared by reduction of (R)- or (R,S)-Mtd with sodium borohydride, followed by esterification with succinic anhydride. The conjugation of hapten with albumin was achieved by the mixed anhydride method. After immunization of rabbits, the titers and specificity of each antibody were determined by ELISA. The antibodies obtained were tested with (R)-, (S)-, (R,S)-Mtd, its major metabolite (EDDP), and some drugs of abuse (morphine, codeine, cocaine). The sensitivities of antibodies to (R)- and (R,S)-Mtd were about 1 and 2 ng/ml, respectively. Selective (R)-antibodies recognized (R)-Mtd about 40 times more avidly than the (S)-isomer, while an antiserum against (R,S)-Mtd recognized (R)- and (S)-isomers to about the same degree. Both selective antibodies showed little interference (about 0.5%) with EDDP metabolite and no crossreactivity with morphine, codeine, and cocaine. These two selective antibodies were used to develop an immunoenzymatic method (ELISA) for the determination of (R)- and (R,S)-Mtd in serum samples of patients under maintenance treatment for narcotic addiction. Chirality 13:187,192, 2001. © 2001 Wiley-Liss, Inc. [source] | ||||||||||