Analytical challenges in human plasma lipidomics: A winding path towards the truth

Human plasma lipidome has been extensively studied in many pathophysiological contexts with the hope of identifying biomarkers for early diagnostics and monitoring the progression and treatment of a broad spectrum of diseases. However, despite remarkable progress in lipidomics technologies, the concordance of lipidomics measurements between independent laboratories remains limited and not fulfilling the criteria of common laboratory diagnostics. Here we highlighted a few critical aspects of epidemiological studies of the plasma lipidome, including the selection of study cohorts, collection of plasma samples as well as extraction, identification and quantification of lipids. We argue that reporting the abundances of plasma lipids as molar concentrations is a key turning point during the transition of research lipidomics into a common tool of clinical diagnostics.