Secretomics – principles of secretome analysis by mass spectrometry
Stefan Lichtenthaler, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
The secretome of a cell comprises soluble, secreted proteins and the membrane protein ectodomains proteolytically released by sheddases (sheddome). Secretome proteins have a major role in central biological processes, including cell-cell communication and adhesion, but are also linked to diseases, such as cancer, inflammation and Alzheimer’s disease.
Additionally, secretome proteins are considered as a rich source for the identification of biomarkers and drug targets. Quantitative proteomics of secretome proteins from cell culture supernatants is in principle possible by mass spectrometry, but has been difficult due to fundamental technical limitations, such as being restricted to serum- and protein-free cell culture conditions. We solved these issues by developing the secretome protein enrichment with click sugars (SPECS) method, which allows proteome-wide identification of secreted proteins from primary cells at unprecedented depth, even in the presence of serum proteins. SPECS combines metabolic glycan labelling and click chemistry-mediated biotinylation and distinguishes between cellular and serum proteins.
This talk presents the SPECS method and its validation as well as additional proteomic methods for secretome analysis.
