Generation of Novel Single-Chain Antibodies by Phage-Display Technology to Direct Imaging Agents Highly Selective to Pancreatic β- or α-Cells In Vivo
| Autor: | Juris J. Meier, Andrea Tannapfel, Sandra Ueberberg, Manfred Köller, Carmen Waengler, Inge Schmitz, Johannes W. Dietrich, Ralf Schirrmacher, Stephan Schneider, Harald Klein, W. Schechinger |
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| Jazyk: | angličtina |
| Rok vydání: | 2009 |
| Předmět: |
medicine.medical_specialty
Biodistribution Phage display Cell Survival Endocrinology Diabetes and Metabolism Apoptosis Biology Endoplasmic Reticulum Antibodies Cell Line Diabetes Mellitus Experimental In vivo Antibody Specificity Internal medicine Insulin-Secreting Cells Internal Medicine medicine Animals Humans geography geography.geographical_feature_category Pancreatic islets Secretory Vesicles Glucose Tolerance Test Islet Immunohistochemistry In vitro Cell biology Rats Microscopy Electron Endocrinology medicine.anatomical_structure Islet Studies Cell culture Glucagon-Secreting Cells Original Article Female Pancreas |
| Zdroj: | Diabetes |
| ISSN: | 1939-327X 0012-1797 |
| Popis: | OBJECTIVE Noninvasive determination of pancreatic β-cell mass in vivo has been hampered by the lack of suitable β-cell–specific imaging agents. This report outlines an approach for the development of novel ligands homing selectively to islet cells in vivo. RESEARCH DESIGN AND METHODS To generate agents specifically binding to pancreatic islets, a phage library was screened for single-chain antibodies (SCAs) on rat islets using two different approaches. 1) The library was injected into rats in vivo, and islets were isolated after a circulation time of 5 min. 2) Pancreatic islets were directly isolated, and the library was panned in the islets in vitro. Subsequently, the identified SCAs were extensively characterized in vitro and in vivo. RESULTS We report the generation of SCAs that bind highly selective to either β- or α-cells. These SCAs are internalized by target cells, disappear rapidly from the vasculature, and exert no toxicity in vivo. Specific binding to β- or α-cells was detected in cell lines in vitro, in rats in vivo, and in human tissue in situ. Electron microscopy demonstrated binding of SCAs to the endoplasmatic reticulum and the secretory granules. Finally, in a biodistribution study the labeling intensity derived from [125I]-labeled SCAs after intravenous administration in rats strongly predicted the β-cell mass and was inversely related to the glucose excursions during an intraperitoneal glucose tolerance test. CONCLUSIONS Our data provide strong evidence that the presented SCAs are highly specific for pancreatic β-cells and enable imaging and quantification in vivo. |
| Databáze: | OpenAIRE |
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