Cutting-edge neurodegenerative disease research at the Emory School of Medicine using Bruker’s timsTOF fleX

Since 2019, Dr. Roberts has led a research group of seven scientists. Alongside characterizing new blood borne biomarkers, his team’s recent research focuses on developing new proteomics technologies to measure metalloproteins. The Roberts Lab is also continuing Dr. Roberts’ original research into blood-based biomarkers and diagnostics, with the focus remaining on leveraging red blood cells instead of plasma as the primary sample in the quest to identify diagnostic markers for Parkinson’s disease. 

This work, and Dr. Roberts’ work going forward, relies on Bruker’s timsTOF fleX which was purchased by the Emory University School of Medicine in 2021. The timsTOF fleX brings trapped ion mobility spectrometry (TIMS) and matrix assisted laser desorption/ionization MALDI Imaging capabilities to Dr. Roberts’ work for the first time.

Although native mass spectrometry (MS) excels in probing protein-ligand complexation or protein binding, it lacks the ability to give definite measurements of the relative molecular size of those complexes on its own. Only recently has the potential of ion mobility spectrometry (IMS) coupled to MS (IMS-MS) been explored for the separation, identification and quantification of peptides and proteins. 

Bruker’s innovation, the timsTOF platform, introduces the next evolution in proteomics technology. The addition of collision cross section (CCS) measurement drives the transition from 3D-Proteomics (retention time, mass to charge (m/z) and MS/MS fragment ion spectra) to 4D-Proteomics™ . 

CCS values have proved consequential in the red blood cell and proteomics work at the Roberts Lab. For the team’s Alzheimer’s disease research, CCS values help to confirm what isomer or modification they are looking at. In the peptide space, having extra characterization of the CCS with the mass and the fragmentation all adds up for higher confidence. 

Using the CCS, the identity of an analyte can be validated with an additional quality criterion. CCS-enabled software intelligently matches spatial MALDI-TIMS imaging data with ‘omics results and enables vital morphological context to ID-lists.

At the Roberts Lab, the group is also investigating the role of amyloid beta in Alzheimer’s disease. There are unanswered questions regarding if amyloid beta isomers are localized exclusively around plaques around brain cells, caused by the build-up of protein, or uniformly distributed throughout the grey matter. 

The timsTOF fleX system’s MALDI Imaging capabilities is the only commercially available solution that provides an ion mobility measurement using MALDI. This has enabled the lab to image amyloid beta isomers which is only possible through the combination of TIMS and MALDI.

Dr. Roberts looks ahead: “With the timsTOF fleX we have not only the proven robust 4D proteomics performance and the advantage of CCS measurement, but also the opportunity to add a spatial dimension to our analysis. Now we know for sure that important molecular modifications are there we want to explore more; we want to discover how they’re organized. This is very exciting work, and we are looking forward to the next stage of our research.”