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Biosensor Technology (biosensor + technology)
Selected AbstractsIgG2 containing IgM,IgG immune complexes predominate in normal human plasma, but not in plasma of patients with warm autoimmune haemolytic anaemiaEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 3 2006Dorothea Stahl Abstract:, The different physicochemical and sterical properties of IgG subclasses may favour a selective enrichment of defined IgG subclasses in IgM,IgG immune complexes (IC) of human plasma under physiological conditions. Such enrichment of IgG subclasses in IgM,IgG IC of plasma may differ from the normal IgG subclass distribution in plasma itself, and contribute to the physiological functions of IgM,IgG IC. Systematic studies on the IgG subclass distribution in IgM,IgG IC in humans are lacking. Using specific analytical techniques to characterise IgM,IgG IC in human plasma (i.e. fast protein liquid chromatography, enzyme-linked immunosorbent assay, affinity biosensor technology), and taking warm autoimmune haemolytic anaemia (WAIHA) of humans as a disease model, we here demonstrate that: (i) IgG2 is the predominant IgG subclass in IgM,IgG IC under physiological conditions, (ii) the predominance of IgG2 within IgM,IgG IC may get lost in polyclonal IgG-mediated autoimmune disease and (iii) the IgG subclass distribution in IgM,IgG IC influences the interaction between IC and blood cells involved in antigen presentation. The data presented here therefore extend the physiological function of IgG2, which is the protective immune response towards carbohydrate antigens in bacterial infections, and suggest IgG2-dependent regulation of immune responses to self-immunoglobulin in humans. The disturbed IgG subclass distribution in IgM,IgG IC of patients with WAIHA might influence activity of self-reactive B cells involved in the pathophysiology of the disease. [source] Survey of the year 2006 commercial optical biosensor literatureJOURNAL OF MOLECULAR RECOGNITION, Issue 5 2007Rebecca L. Rich Abstract We identified 1219 articles published in 2006 that described work performed using commercial optical biosensor platforms. It is interesting to witness how the biosensor market is maturing with an increased number of instrument manufacturers offering a wider variety of platforms. However, it is clear from a review of the results presented that the advances in technology are outpacing the skill level of the average biosensor user. While we can track a gradual improvement in the quality of the published work, we clearly have a long way to go before we capitalize on the full potential of biosensor technology. To illustrate what is right with the biosensor literature, we highlight the work of 10 groups who have their eye on the ball. To help out the rest of us who have the lights on but nobody home, we use the literature to address common myths about biosensor technology. Copyright © 2007 John Wiley & Sons, Ltd. [source] BIACORE J: a new platform for routine biomolecular interaction analysis,JOURNAL OF MOLECULAR RECOGNITION, Issue 4 2001Rebecca L. Rich Abstract SPR biosensor technology continues to evolve. The recently released platform from Biacore AB (Uppsala, Sweden), BIACORE J, is designed for the routine analysis of biomolecular interactions. Using an antibody,protein A and a ligand,receptor system, we demonstrate the utility of BIACORE J in determining active concentration and binding affinities. The results from these studies illustrate the high sensitivity of the instrument and its ability to generate reproducible binding responses. The BIACORE J is easy to operate and useful in diverse applications, making SPR technology widely accessible as a research tool. Copyright © 2001 John Wiley & Sons, Ltd. [source] Characterizing a drug's primary binding site on albuminJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 2 2003Yasmina S.N. Day Abstract Surface plasmon resonance-based biosensors can be used to directly measure the binding of small molecules to albumin. We studied 12 drugs with different molecular masses and affinities for albumin to illustrate the benefits of the technology. To examine both high- and low-affinity sites on the protein, each drug was assayed across a 10,000-fold concentration range. The affinity constants determined from the biosensor assay corresponded with affinities determined by other methods. We expanded the utility of the biosensor technology by developing protocols to characterize drug displacement from albumin. Finally, we also compared how a representative panel of drugs bound albumins from 14 species. The results illustrate how biosensors can provide detailed information about the identification and affinity of a drug's primary binding site on albumin. © 2003 Wiley-Liss, Inc. and the American Pharmaceutical Association J Pharm Sci 92:333,343, 2003 [source] Affibody-mediated transferrin depletion for proteomics applicationsBIOTECHNOLOGY JOURNAL, Issue 11 2007Caroline Grönwall Abstract An Affibody® (Affibody) ligand with specific binding to human transferrin was selected by phage display technology from a combinatorial protein library based on the staphylococcal protein A (SpA)-derived Z domain. Strong and selective binding of the selected Affibody ligand to transferrin was demonstrated using biosensor technology and dot blot analysis. Impressive specificity was demonstrated as transferrin was the only protein recovered by affinity chromatography from human plasma. Efficient Affibody-mediated capture of transferrin, combined with IgG- and HSA-depletion, was demonstrated for human plasma and cerebrospinal fluid (CSF). For plasma, 85% of the total transferrin content in the samples was depleted after only two cycles of transferrin removal, and for CSF, 78% efficiency was obtained in single-step depletion. These results clearly suggest a potential for the development of Affibody-based resins for the removal of abundant proteins in proteomics analyses. [source] |