Nicolai Bache (Presenter)
Bruker Daltonics Inc.
Authorship: Jerome Vialaret(1), Sylvain Lehmann(1), Audrey Gabelle(1,2), P.O Schmit(3), Nicolai Bache(4) and Christophe Hirtz(1)
(1) Laboratoire de Biochimie et Protéomique Clinique, Institut de Médecine Régénératrice et de Biothérapie, CHU de Montpellier - Hôpital St. Eloi, Montpellier, France. (2) Centre Mémoire Ressources Re
| Short Abstract In this study we have used a quantitative proteoform profiling experiment to detect and identify several potential biomarkers for Alzheimer’s disease based on cerebrospinal fluid (CSF). We were able to comfortably and reproducibly detect more than 1500 proteoforms in each sample leading to the detection and identification of 77 differentially regulated proteoforms (potential biomarker candidates) which are currently being identified and validated through a scheduled top-down MS/MS approach. Many of those correspond to proteoforms of proteins carrying a specific modification, a mutation or having undergone a proteolytic modification which would have made their characterization much more challenging, if not impossible, with a bottom-up workflow. |
Long Abstract
Measuring the intact masses of proteins from biological samples provides important insight into biological events which cannot be analyzed by standard bottom-up strategies. Despite technical limitations, mainly due to the large size of the biomolecules being measured, it has gained significant momentum over the last couple of years from improvements in both the general workflows and the associated technologies. Being able to analyze intact proteins rather than their proteolytic peptides enables direct measurements of the major and very important biological processes like alternative splicing, proteolytic processing and post translational modifications – including the complex patterns and stoichiometry of multi-modified proteins. The first step in this approach is to establish a set of quantitative proteoform profiles. The differentially expressed features are then targeted and subsequently identified through a separate top-down MS/MS experiment and if needed a more comprehensive characterization.
In this study we have used a quantitative proteoform profiling experiment to detect and identify several potential biomarkers for Alzheimer’s disease based on cerebrospinal fluid (CSF). We were able to comfortably and reproducibly detect more than 1500 proteoforms in each sample leading to the detection and identification of 77 differentially regulated proteoforms (potential biomarker candidates) which are currently being identified and validated through a scheduled top-down MS/MS approach. Many of those correspond to proteoforms of proteins carrying a specific modification, a mutation or having undergone a proteolytic modification which would have made their characterization much more challenging, if not impossible, with a bottom-up workflow. One clear example of this is the diagnostic 1:2 distribution of the truncated and mutated versions of Secretogranin 2 which also clearly illustrates the big potential of the proteoform profiling approach. We are currently extending this study to larger cohorts of patients to both validate our current findings and potentially expand the list of new potential biomarkers.
References & Acknowledgements:
| Description | Y/N | Source |
| Grants | no | |
| Salary | yes | Bruker Daltonics |
| Board Member | no | |
| Stock | no | |
| Expenses | no |
IP Royalty: no
| Planning to mention or discuss specific products or technology of the company(ies) listed above: | yes |