title: Sensitive detection of idiotypic platelet-reactive alloantibodies by an electrical protein chip.
abstract: To prevent and treat immune-mediated platelet disorders (e.g. neonatal allo-immune thrombocytopenia and platelet transfusion refractoriness) the causative idiotypic platelet-reactive antibodies have to be detected with high sensitivity and specificity. The "Monoclonal Antibody Immobilization Platelet Assay" (MAIPA) is the diagnostic gold standard for immunotyping sera with respect to alloantibodies against human platelet antigens (HPA). However, it is labor-intensive and time-consuming. In this work, an automated protein chip assay (enzyme-linked sandwich immunoassay) based on interdigitated gold microelectrodes in combination with an electrical read-out system was developed and optimized. For this purpose, specific capture antibodies were immobilized on the gold electrodes. The binding of the target is detected via an enzyme-labeled detection antibody by a redox-recycling process that corresponds to the amount of bound target molecule. With this electrical chip assay it is possible to detect antibodies against HPA-1a, HPA-5b and HLA with high sensitivity and specificity in less than half the duration of the MAIPA protocol with similar intra- and interassay variance.
authors.affiliation: Pharmazeutische Biotechnologie, Institut für Pharmazie, Ernst-Moritz-Arndt-Universität, Greifswald, Germany.
authors.forename: Annett
authors.initials: A
authors.lastname: Quiel
authors.forename: Britta
authors.initials: B
authors.lastname: Jürgen
authors.forename: Andreas
authors.initials: A
authors.lastname: Greinacher
authors.forename: Susan
authors.initials: S
authors.lastname: Lassen
authors.forename: Ralf
authors.initials: R
authors.lastname: Wörl
authors.forename: Sabine
authors.initials: S
authors.lastname: Witt
authors.forename: Thomas
authors.initials: T
authors.lastname: Schweder
mesh_terms: D000911:Antibodies, Monoclonal / Q000737:chemistry; D016824:Antigens, Human Platelet / Q000032:analysis*; D015374:Biosensing Techniques; D001791:Blood Platelet Disorders / Q000175:diagnosis; D055664:Electrochemical Techniques; D006046:Gold; D006680:HLA Antigens / Q000032:analysis; D006801:Humans; D007518:Isoantibodies / Q000032:analysis* / Q000097:blood; D008839:Microelectrodes; D040081:Protein Array Analysis / Q000379:methods; D012680:Sensitivity and Specificity; D013921:Thrombocytopenia / Q000175:diagnosis
chemical_list: D000911:Antibodies, Monoclonal; D016824:Antigens, Human Platelet; D006680:HLA Antigens; D007518:Isoantibodies; D006046:Gold