GNPS - HIV-Associated Neurocognitive Disorder Column Test
Ontology highlight
ABSTRACT: Plasma and Cerebrospinal fluid data were acquired on the Q-Exactive with 3 different columns: a C8 column, a C18 column, and a polar C18 Column.
Project description:Plasma and Cerebrospinal fluid data were acquired on the Q-Exactive with 3 different columns: a C8 column, a C18 column, and a polar C18 Column.
Project description:Although the benefits of reduction of the size of reversed phase particles are established to provide increased sequencing depth and improved chromatography in LCMS experiments, the wide-scale adoption of optimally sized small particles in reversed-phase columns has been hampered by the necessity for specialized equipment such as ultra-high pressure liquid chromatography or a customized column heating apparatus. Here, we introduce a new strategy to routinely fabricate a 50 cm-long, 1.9 µm particle C18 column and extensively characterize the performance of this column. This column was packed under 100 Bar and routinely utilized on a standard quarternary HPLC at pressures below 300 Bar. Expanding the depth of sequencing of peptides that show a statistically significant quantitative change arising from a biological stimulation is critical. Compared with traditional C18 columns packed with 3 µm particles, the column with the 1.9 µm particles operated with a standard HPLC could detect 330% more peptides with statistically significant changes from differentially stimulated T cells. This improved column fabrication methodology provides an inexpensive improvement for single-run LC-MS/MS analysis to optimize sequencing depth, dynamic range, sensitivity, and reproducibility. This study also highlights the importance of the statistical analysis of quantitative proteomic data instead of a sole focus on peptide spectrum match yields.
Project description:Fe-IMAC columns for robust and reproducible phosphopeptide ernichment, comparison to TiO2 batch and Ti-IMAC tip enrichment, large scale phosphoproteomics coupling Fe-IMAC column pre-enrichment to subsequent hSAX separation
Project description:This SuperSeries is composed of the following subset Series: GSE37664: Human cerebrospinal fluid autoantibody lipid microarray profiling (Fig. 1A) GSE37670: Human cerebrospinal fluid autoantibody lipid microarray profiling (Fig. 2A) GSE37826: Human cerebrospinal fluid autoantibody lipid microarray profiling (Fig. 2C) Refer to individual Series
Project description:A comprehensive proteome map is essential to elucidate molecular pathways and protein functions. Although great improvements in sample preparation, instrumentation and data analysis already yield-ed impressive results, current studies suffer from a limited proteomic depth and dynamic range there-fore lacking low abundant or highly hydrophobic proteins. Here, we combine and benchmark advanced micro pillar array columns (µPAC) operated at nanoflow with Wide Window Acquisition (WWA) and the AI-based CHIMERYS search engine for data analysis to maximize chromatographic separation power, sensitivity and proteome coverage. Our data shows that µPAC columns clearly outperform classical packed bed columns boosting peptide IDs by up to 50% and protein IDs by up to 24%. Using the above-mentioned analysis platform, more than 10,000 proteins could be identified from a single 2 h gradient shotgun analysis for a triple proteome mix of human, yeast and E. coli digests. At high sample loads of 400 ng all three uPAC types yielded comparable number of protein identifications, whereas the 50cm neo column performed best when lower inputs of less than 200 ng were injected. This additional dataset comprises additional data generated with the Aurora Elite G3 column (150 mm x 75 µm, 1.7 µm, IonOpticks) for comparison to the aforementioned µPAC technology.
Project description:Claudin proteins are major constituents of epithelial and endothelial tight junctions (TJ), where they serve as regulators of paracellular permeability to ions and solutes. Claudin-18, a member of the large claudin family, is highly expressed in lung epithelium. To elucidate the role of claudin-18 in alveolar epithelial barrier function and fluid homeostasis, we generated claudin-18 knockout (C18 KO) mice. Increased alveolar fluid clearance (AFC) observed in C18 KO mice may have accounted for absence of lung edema despite increased alveolar solute permeability compared to wild type (WT) controls. Higher AFC in C18 KO mice was associated with higher Na-K-ATPase activity and increased expression of the Na-K-ATPase β1 subunit compared to WT controls. Consistent with in vivo findings, alveolar epithelial cell (AEC) monolayers derived from C18 KO mice exhibited lower transepithelial electrical resistance (RT) accompanied by increased solute and ion permeability without changes in ion selectivity. Expression of claudin-3 and claudin-4 was markedly increased in whole lung and in freshly isolated AEC from C18 KO mice, while claudin-5 was unchanged. In contrast, occludin, another major component of the TJ complex, was significantly decreased in C18 KO lung. Further analysis revealed rearrangements in the F-actin cytoskeleton in C18 KO MAECM. These findings demonstrate a crucial non-redundant role for claudin-18 in regulation of alveolar epithelial tight junction composition and permeability to ions and solutes. Importantly, increased AFC in C18 KO mice identifies additional roles for claudin-18 in alveolar fluid homeostasis beyond its direct contributions to barrier properties of the alveolar epithelium. Animals with a ubiquitous knockout (C18 KO) were obtained by crossing mice harboring a conditional (floxed) allele of claudin-18 (Cldn18F/F) with CMV-cre deleter mice to delete exons 2 and 3 by Cre/loxP recombination.
Project description:Claudin proteins are major constituents of epithelial and endothelial tight junctions (TJ), where they serve as regulators of paracellular permeability to ions and solutes. Claudin-18, a member of the large claudin family, is highly expressed in lung epithelium. To elucidate the role of claudin-18 in alveolar epithelial barrier function and fluid homeostasis, we generated claudin-18 knockout (C18 KO) mice. Increased alveolar fluid clearance (AFC) observed in C18 KO mice may have accounted for absence of lung edema despite increased alveolar solute permeability compared to wild type (WT) controls. Higher AFC in C18 KO mice was associated with higher Na-K-ATPase activity and increased expression of the Na-K-ATPase β1 subunit compared to WT controls. Consistent with in vivo findings, alveolar epithelial cell (AEC) monolayers derived from C18 KO mice exhibited lower transepithelial electrical resistance (RT) accompanied by increased solute and ion permeability without changes in ion selectivity. Expression of claudin-3 and claudin-4 was markedly increased in whole lung and in freshly isolated AEC from C18 KO mice, while claudin-5 was unchanged. In contrast, occludin, another major component of the TJ complex, was significantly decreased in C18 KO lung. Further analysis revealed rearrangements in the F-actin cytoskeleton in C18 KO MAECM. These findings demonstrate a crucial non-redundant role for claudin-18 in regulation of alveolar epithelial tight junction composition and permeability to ions and solutes. Importantly, increased AFC in C18 KO mice identifies additional roles for claudin-18 in alveolar fluid homeostasis beyond its direct contributions to barrier properties of the alveolar epithelium.