LC-MS-based proteomics requires methods with highpeak capacity and a high degree of automation, integratedwith data-handling tools able to cope with the massive dataproduced and able to quantitatively compare them. Thispaper describes an off-line two-dimensional (2D) LC-MSmethod and its integration with software tools for datapreprocessing and multivariate statistical analysis. The 2DLC-MS method was optimized in order to minimizepeptide loss prior to sample injection and during thecollection step after the first LC dimension, thus minimizing errors from off-column sample handling. The seconddimension was run in fully automated mode, injectingonto a nanoscale LC-MS system a series of more than100 samples, representing fractions collected in the firstdimension (8 fractions/sample). As a model study, themethod was applied to finding biomarkers for the antiinflammatory properties of zilpaterol, which are coupled tothe
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2-adrenergic receptor. Secreted proteomes fromU937 macrophages exposed to lipopolysaccharide in thepresence or absence of propanolol or zilpaterol wereanalysed. Multivariate statistical analysis of 2D LC-MSdata, based on principal component analysis, and subsequent targeted LC-MS/MS identification of peptides ofinterest demonstrated the applicability of the approach.