Databases for antibody-based proteomics

Abstract: Humans are believed to have ~20,500 protein-coding genes andmuch effort has over the last years been put into the characterizationand localization of the encoded proteins in order to understand theirfunctions. One such effort is the Human Proteome Resource (HPR)project, started in Sweden 2003 with the aim to generate specificantibodies to each human protein and to use those antibodies toanalyze the human proteome by screening human tissues and cells.The work reported in this thesis deals with structuring of data fromantibody-based proteomics assays, with focus on the importance ofaggregating and presenting data in a way that is easy to apprehend.The goals were to model and build databases for collecting, searchingand analyzing data coming out of the large-scale HPR project and tomake all collected data publicly available. A public website, theHuman Protein Atlas, was developed giving all end-users in thescientific community access to the HPR database with proteinexpression data. In 2008, the Human Protein Atlas was released in its4th version containing more than 6000 antibodies, covering more than25% of the human proteins. All the collected protein expression datais searchable on the public website. End-users can query for proteinsthat show high expression in one tissue and no expression in anotherand possibly find tissue specific biomarkers. Queries can also beconstructed to find proteins with different expression levels in normalvs. cancer tissues. The proteins found by such a query could identifypotential biomarkers for cancer that could be used as diagnosticmarkers and maybe even be involved in cancer therapy in the future.Validation of antibodies is important in order to get reliable resultsfrom different assays. It has been noted that some antibodies arereliable in certain assays but not in others and therefore anotherpublicly available database, the Antibodypedia, has been createdwhere any antibody producer can submit their binders together withthe validation data in order for end users to purchase the bestantibody for their protein target and their intended assay.