Project description:The E4 allele of Apolipoprotein E (APOE) is associated with both metabolic dysfunction and a heightened pro-inflammatory response – two findings that may be intrinsically linked through the concept of immunometabolism. Here, we combined bulk, single-cell, and spatial transcriptomics with cell-specific and spatially resolved metabolic analyses to systematically address the role of APOE across age, neuroinflammation, and AD pathology. RNAseq highlighted immunometabolic changes across the APOE4 glial transcriptome, specifically in subsets of metabolically distinct microglia enriched in the E4 brain during aging or following an inflammatory challenge. E4 microglia display increased Hif1a expression, a disrupted TCA cycle, and are inherently pro-glycolytic, while spatial transcriptomics and MALDI mass spectrometry imaging highlight an E4-specific response to amyloid that is characterized by widespread alterations in lipid metabolism. Taken together, our findings emphasize a central role for APOE in regulating microglial immunometabolism.
Project description:Comprehensive map of first- and second-trimester gonadal development in humans using a combination of single-cell and spatial transcriptomics, chromatin accessibility assays, and imaging.
Project description:RATIONALE
In spatial proteomics, matrix-assisted laser desorption/ionization (MALDI) imaging enables rapid and cost-effective peptide measurement. Yet, in situ peptide identification remains challenging. Therefore, this study aims to integrate the trapped ion mobility spectrometry (TIMS)-based parallel accumulation-serial fragmentation (PASEF) into MALDI imaging of peptides to enable multiplexed MS/MS imaging.
METHODS
An initial MALDI TIMS MS1 survey measurement is performed, followed by a manual generation of a precursor list containing mass over charge values and ion mobility windows. Inside the dual TIMS system, submitted precursors are trapped, separately eluted by their ion mobility and analyzed in a quadrupole time-of-flight device, thereby enabling multiplexed MALDI MS/MS imaging. Finally, precursors are identified by peptide to spectrum matching.
RESULTS
This study presents the first multiplexed MALDI TIMS MS/MS imaging (iprm-PASEF) of tryptic peptides. Its applicability is showcased on two histomorphologically distinct tissue specimens in a 4-plex and 5-plex setup. Precursors were successfully identified by the search engine MASCOT in one single MALDI imaging experiment for each respective tissue. Peptide identifications were corroborated by liquid-chromatography tandem mass spectrometry experiments and fragment colocalization analyses.
CONCLUSIONS
In the present study, we demonstrate the feasibility of TIMS-based MALDI MS/MS imaging for the multiplexed and rapid identification of tryptic peptides in a spatial manner. Hence, it represents a first step towards the integration of MALDI imaging into the emerging field of spatial proteomics.
The datasets will be uploaded separately. This data set contains the PDX MS1 data. There are two tissues vissible on the.tif image. The relevant one is on the left side of the slide (away from the barcode).
Project description:RATIONALE
In spatial proteomics, matrix-assisted laser desorption/ionization (MALDI) imaging enables rapid and cost-effective peptide measurement. Yet, in situ peptide identification remains challenging. Therefore, this study aims to integrate the trapped ion mobility spectrometry (TIMS)-based parallel accumulation-serial fragmentation (PASEF) into MALDI imaging of peptides to enable multiplexed MS/MS imaging.
METHODS
An initial MALDI TIMS MS1 survey measurement is performed, followed by a manual generation of a precursor list containing mass over charge values and ion mobility windows. Inside the dual TIMS system, submitted precursors are trapped, separately eluted by their ion mobility and analyzed in a quadrupole time-of-flight device, thereby enabling multiplexed MALDI MS/MS imaging. Finally, precursors are identified by peptide to spectrum matching.
RESULTS
This study presents the first multiplexed MALDI TIMS MS/MS imaging (iprm-PASEF) of tryptic peptides. Its applicability is showcased on two histomorphologically distinct tissue specimens in a 4-plex and 5-plex setup. Precursors were successfully identified by the search engine MASCOT in one single MALDI imaging experiment for each respective tissue. Peptide identifications were corroborated by liquid-chromatography tandem mass spectrometry experiments and fragment colocalization analyses.
CONCLUSIONS
In the present study, we demonstrate the feasibility of TIMS-based MALDI MS/MS imaging for the multiplexed and rapid identification of tryptic peptides in a spatial manner. Hence, it represents a first step towards the integration of MALDI imaging into the emerging field of spatial proteomics.
All Datasets are uploaded separateley. This file contains the dataset for mouse kidney MS1 data.
On the same slice a mouse liver was measured for a different experiment.
Project description:RATIONALE
In spatial proteomics, matrix-assisted laser desorption/ionization (MALDI) imaging enables rapid and cost-effective peptide measurement. Yet, in situ peptide identification remains challenging. Therefore, this study aims to integrate the trapped ion mobility spectrometry (TIMS)-based parallel accumulation-serial fragmentation (PASEF) into MALDI imaging of peptides to enable multiplexed MS/MS imaging.
METHODS
An initial MALDI TIMS MS1 survey measurement is performed, followed by a manual generation of a precursor list containing mass over charge values and ion mobility windows. Inside the dual TIMS system, submitted precursors are trapped, separately eluted by their ion mobility and analyzed in a quadrupole time-of-flight device, thereby enabling multiplexed MALDI MS/MS imaging. Finally, precursors are identified by peptide to spectrum matching.
RESULTS
This study presents the first multiplexed MALDI TIMS MS/MS imaging (iprm-PASEF) of tryptic peptides. Its applicability is showcased on two histomorphologically distinct tissue specimens in a 4-plex and 5-plex setup. Precursors were successfully identified by the search engine MASCOT in one single MALDI imaging experiment for each respective tissue. Peptide identifications were corroborated by liquid-chromatography tandem mass spectrometry experiments and fragment colocalization analyses.
CONCLUSIONS
In the present study, we demonstrate the feasibility of TIMS-based MALDI MS/MS imaging for the multiplexed and rapid identification of tryptic peptides in a spatial manner. Hence, it represents a first step towards the integration of MALDI imaging into the emerging field of spatial proteomics.
The datasets will be uploaded separately. This data set contains the PDX MSMS data. There are two tissues vissible on the.tif image. The relevant one is on the left side of the slide (away from the barcode).
Project description:RATIONALE
In spatial proteomics, matrix-assisted laser desorption/ionization (MALDI) imaging enables rapid and cost-effective peptide measurement. Yet, in situ peptide identification remains challenging. Therefore, this study aims to integrate the trapped ion mobility spectrometry (TIMS)-based parallel accumulation-serial fragmentation (PASEF) into MALDI imaging of peptides to enable multiplexed MS/MS imaging.
METHODS
An initial MALDI TIMS MS1 survey measurement is performed, followed by a manual generation of a precursor list containing mass over charge values and ion mobility windows. Inside the dual TIMS system, submitted precursors are trapped, separately eluted by their ion mobility and analyzed in a quadrupole time-of-flight device, thereby enabling multiplexed MALDI MS/MS imaging. Finally, precursors are identified by peptide to spectrum matching.
RESULTS
This study presents the first multiplexed MALDI TIMS MS/MS imaging (iprm-PASEF) of tryptic peptides. Its applicability is showcased on two histomorphologically distinct tissue specimens in a 4-plex and 5-plex setup. Precursors were successfully identified by the search engine MASCOT in one single MALDI imaging experiment for each respective tissue. Peptide identifications were corroborated by liquid-chromatography tandem mass spectrometry experiments and fragment colocalization analyses.
CONCLUSIONS
In the present study, we demonstrate the feasibility of TIMS-based MALDI MS/MS imaging for the multiplexed and rapid identification of tryptic peptides in a spatial manner. Hence, it represents a first step towards the integration of MALDI imaging into the emerging field of spatial proteomics.
The datasets will be uploaded separately. This data set contains the Kidney MSMS data. There is an additional Liver tissue vissible on the .tif image. This was used for another experiment
Project description:IntroductionTranscranial direct current stimulation (tDCS) is an evolving non-invasive neurostimulation technique. Despite multiple studies, its underlying molecular mechanisms are still unclear. Several previous human studies of the effect of tDCS suggest that it generates metabolic effects. The induction of metabolic effects by tDCS could provide an explanation for how it generates its long-term beneficial clinical outcome.AimGiven these hints of tDCS metabolic effects, we aimed to delineate the metabolic pathways involved in its mode of action.MethodsTo accomplish this, we utilized a broad analytical approach of co-analyzing metabolomics and transcriptomic data generated from anodal tDCS in rat models. Since no metabolomic dataset was available, we performed a tDCS experiment of bilateral anodal stimulation of 200 µA for 20 min and for 5 consecutive days, followed by harvesting the brain tissue below the stimulating electrode and generating a metabolomics dataset using LC-MS/MS. The analysis of the transcriptomic dataset was based on a publicly available dataset.ResultsOur analyses revealed that tDCS alters the metabolic profile of brain tissue, affecting bioenergetic-related pathways, such as glycolysis and mitochondrial functioning. In addition, we found changes in calcium-related signaling.ConclusionsWe conclude that tDCS affects metabolism by modulating energy production-related processes. Given our findings concerning calcium-related signaling, we suggest that the immediate effects of tDCS on calcium dynamics drive modifications in distinct metabolic pathways. A thorough understanding of the underlying molecular mechanisms of tDCS has the potential to revolutionize its applicability, enabling the generation of personalized medicine in the field of neurostimulation and thus contributing to its optimization.