Daniel J. Ryan, David Nei, Boone M. Prentice, Kristie L. Rose, Richard M. Caprioli, Jeffrey M. Spraggins
Robotic liquid surface extractions can be used to interrogate discrete regions of tissue to provide protein identifications with high throughput, accuracy, and robustness. The direct coupling of tissue surface extractions and liquid chromatography, offers a new and effective approach to provide spatial proteomics data in an imaging experiment.
Tissue extractions were completed using the TriVersa NanoMate® (Advion, Inc., Ithaca, NY, USA) modified to include a glass capillary (LESA Plus) for improved spatial resolution and online integration with LC-based experiments. 36 Scanned images of thaw-mounted samples were uploaded to the ChipSoft Software (Advion, Inc.) to allow histological regions of interest to be selected for analysis.
Lieke Lamont, Mark Baumert, Nina Ogrinc Potočnik, Mark Allen, Rob Vreefken, Ron M. A. Heeren, and Tiffany Porta
Direct analysis by mass spectrometry (imaging) has become increasingly deployed in preclinical and clinical research due to its rapid and accurate readouts. However, when it comes to biomarker discovery or histopathological diagnostics, more sensitive and in-depth profi ling from localized areas is required. We developed a comprehensive, fully automated online platform for high-resolution liquid extraction surface analysis (HR-LESA) followed by micro−liquid chromatography (LC) separation and a data-independent acquisition strategy for untargeted and low abundant analyte identifi cation directly from tissue sections. Applied to tissue sections of rat pituitary, the platform demonstrated improved spatial resolution, allowing sample areas as small as 400 μ m to be studied, a major advantage over conventional LESA.
The LESA extraction was performed using the automated TriVersa NanoMate® The LESA extraction was controlled by a beta version of the LESA Plus software (Advion, UK)
Rian L. Griffiths, Emma K. Sisley, Andrea F. Lopez-Clavija, Anna L. Simmonds, Iain B. Styles, Helen J. Cooper
Here, researchers present native liquid extraction surface analysis (LESA) mass spectrometry imaging of proteins and protein complexes from mouse brain and liver tissue. Intact proteins were detected in characteristically low charge states, indicating that the proteins remain folded. In brain, abundant proteins such as ubiquitin and β thymosin 4 were detected homogeneously across the tissue whereas other proteins, such as neurogranin, were localised in specific anatomical regions.
In liver, imaging of a protein complex (tetrameric hemoglobin) is demonstrated, as well as fatty acid binding protein. Interestingly, the use of native-like solvents enables extraction of proteins which have not previously been observed in LESA experiments employing denaturing solvents, i.e., native LESA can be applied to extend the range of proteins observed. In addition native LESA ion mobility spectrometry is presented and shows that the collision cross sections of proteins extracted from tissue may be determined by travelling wave ion mobility spectrometry. The collision cross section of the 5+ ion of ubiquitin was calculated as 1047 Å2, in good agreement with measurements of ubiquitin protein standard solutions. Collision cross sections for the 4+ ions of β-thymosin 4, β-thymosin 10 and two unidentified proteins were also calculated, together with that of a 10+ ion of an unidentified protein of molecular weight 15660 Da.
For mass spectrometry and mass spectrometry imaging, the samples were introduced to the mass spectrometer via nanoESI using a TriVersa NanoMate® (Advion Biosciences, Ithaca, USA). The exact location to be sampled was selected using the LESA® Points software (Advion).
The TriVersa NanoMate® LESA® is the latest in chip-based electrospray ionization technology from Advion Interchim Scientific®. It combines the benefits of liquid chromatography, mass spectrometry, chip-based infusion, fraction collection and direct surface analysis into one integrated ion source platform. It allows scientists to obtain more information from complex samples than LC/MS alone.
The early stages of nonalcoholic fatty liver disease (NAFLD) are characterized by the accumulation of fat in the liver (steatosis). This can lead to cell injury and inflammation resulting in nonalcoholic steatohepatitis (NASH). To determine whether lipid profiling of liver tissue can identify metabolic signatures associated with disease presence and severity, we explored liquid extraction surface analysis mass spectrometry (LESA−MS, Advion TriVersa NanoMate with LESA PLUS) as a novel sampling tool. Using LESA−MS, lipids were extracted directly from the surface of ultrathin slices of liver tissue prior to detection by high-resolution mass spectrometry (MS).
We compared the data obtained by LESA− MS to that from liquid chromatography (LC)− MS and matrix-assisted laser desorption ionization MS. Advantages of LESA− MS include rapid analysis, minimal sample preparation, and high lipid coverage.
Furthermore, since tissue slices are routinely used for diagnostics in clinical settings, LESA− MS is ideally placed to complement traditional histology. Overall LESA− MS is found to be a robust, fast, and discriminating approach for determining NAFLD presence and severity in clinical samples.
Infusion based lipidomics analysis (shotgun Lipidomics) is an analysis strategy that involves the liquid extraction of lipids from samples such as blood, tissue homogenates or dried blood spots. This approach is suitable for a wide range of biomedical questions of lipid differentiation and lipid flux in the field of metabolic disease, neurological disorders, cancers or eye diseases. See how utilizing the Advion Interchim Scientific TriVersa NanoMate® can be used for high throughput shotgun Lipidomics analysis.
Published by the International Journal of Mass Spectrometry
Native liquid extraction surface analysis (LESA) mass spectrometry enables the direct sampling of protein complexes from a solid surface. We have previously demonstrated native LESA mass spectrometry of holomyoglobin (~17 kDa) from glass slides and tetrameric haemoglobin (~64 kDa) from dried blood spots and thin tissue sections. Here, we further explore the capabilities of this
emerging technique by investigating a range of proteins which exist in various oligomeric states in vivo.
Victor A.Mikhailov, Rian L.Griffiths, Helen J.Cooper,
Liquid Extraction Surface Analysis for Native Mass Spectrometry: Protein
Complexes and Ligand Binding, International Journal of Mass Spectrometry
http://dx.doi.org/10.1016/j.ijms.2016.09.011
Liquid Extraction Surface Analysis Mass Spectrometry (LESA-MS) has been utilized for determination of small molecules, lipids and proteins from a variety of surfaces such as tissue sections, plant material, medical devices, TLC plates or DBS cards. It allows direct surface analysis without sample preparation from spot sizes of 1 mm diameter by aspiration of extraction solvent into a pipette tip, formation of a liquid junction at the intended target location and extraction of the analytes of interest. In the final step, analytes are ionized by static nano electrospray and detected in the mass spectrometer.
Liquid Extraction Surface Analysis (LESA) is a new, high throughput tool for ambient mass spectrometry. A solvent droplet is deposited from a pipette tip onto a surface and maintains contact with both the surface and the pipette tip for a few seconds before being re-aspirated. The technique is particularly suited to the analysis of trace materials on surfaces due to its high sensitivity and low volume of sample removal. In this work, we assess the suitability of LESA for obtaining detailed chemical profiles of fingerprints, oral fluid and urine, which may be used in future for rapid medical diagnostics or metabolomics studies. We further show how LESA can be used to detect illicit drugs and their metabolites in urine, oral fluid and fingerprints. This makes LESA a potentially useful tool in the growing field of fingerprint chemical analysis, which is relevant not only to forensics but also to medical diagnostics. Finally, we show how LESA can be used to detect the explosive material RDX in contaminated artificial fingermarks.
