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1.
Nat Commun ; 15(1): 2168, 2024 Mar 09.
Article in English | MEDLINE | ID: mdl-38461149

ABSTRACT

In common with other omics technologies, mass spectrometry (MS)-based proteomics produces ever-increasing amounts of raw data, making efficient analysis a principal challenge. A plethora of different computational tools can process the MS data to derive peptide and protein identification and quantification. However, during the last years there has been dramatic progress in computer science, including collaboration tools that have transformed research and industry. To leverage these advances, we develop AlphaPept, a Python-based open-source framework for efficient processing of large high-resolution MS data sets. Numba for just-in-time compilation on CPU and GPU achieves hundred-fold speed improvements. AlphaPept uses the Python scientific stack of highly optimized packages, reducing the code base to domain-specific tasks while accessing the latest advances. We provide an easy on-ramp for community contributions through the concept of literate programming, implemented in Jupyter Notebooks. Large datasets can rapidly be processed as shown by the analysis of hundreds of proteomes in minutes per file, many-fold faster than acquisition. AlphaPept can be used to build automated processing pipelines with web-serving functionality and compatibility with downstream analysis tools. It provides easy access via one-click installation, a modular Python library for advanced users, and via an open GitHub repository for developers.


Subject(s)
Proteomics , Software , Proteomics/methods , Mass Spectrometry/methods , Proteome
2.
RMD Open ; 10(1)2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38360038

ABSTRACT

OBJECTIVE: Interim analysis of the RELIANCE registry, an on-going, non-interventional, open-label, multicentre, prospective study evaluating the long-term safety, dosing regimens and effectiveness of canakinumab in patients with cryopyrin-associated periodic syndromes (CAPS), familial Mediterranean fever (FMF), tumour-necrosis factor receptor-associated periodic syndrome (TRAPS) or mevalonate-kinase deficiency (MKD)/hyperimmunoglobulin-D syndrome (HIDS). METHODS: From September 2017 for patients with CAPS, and June 2018 for patients with FMF, TRAPS or MKD/HIDS, the registry enrolled paediatric (aged ≥2 years) and adult patients (aged ≥18 years) receiving canakinumab as part of their routine medical care. Safety, canakinumab dose, disease activity and quality of life outcome measures were evaluated at baseline and every 6 months until end of study visit. RESULTS: At the analysis cut-off date (December 2020), 168 patients (91 CAPS, 54 FMF, 16 TRAPS and 7 MKD/HIDS) were enrolled. 85 (50.9%) patients were female and 72 (43.1%) were children (<18 years). The median patient age was 20.0 years (range 2.0-79.0 years). In the CAPS cohort, serious infections and serious adverse drug-reactions were more common in patients receiving higher than the recommended starting dose (SD) of canakinumab. A trend to receive >SD of canakinumab was observed in the pooled population. The majority of patients were reported as having either absent or mild/moderate disease activity (physician's global assessment) from baseline to Month 30, with a stable proportion of patients (~70%) in remission under canakinumab treatment. Patient-reported disease activity (Visual Analogue Scale (VAS), Autoinflammatory Disease Activity Index), fatigue (VAS); markers of inflammation (C-reactive protein, serum amyloid A and erythrocyte sedimentation rate) remained well-controlled throughout. CONCLUSION: Data from this analysis confirm the long-term safety and effectiveness of canakinumab for the treatment of CAPS, FMF, TRAPS and MKD/HIDS.


Subject(s)
Antibodies, Monoclonal, Humanized , Cryopyrin-Associated Periodic Syndromes , Familial Mediterranean Fever , Mevalonate Kinase Deficiency , Adult , Humans , Child , Female , Adolescent , Male , Prospective Studies , Quality of Life , Familial Mediterranean Fever/drug therapy , Cryopyrin-Associated Periodic Syndromes/diagnosis , Cryopyrin-Associated Periodic Syndromes/drug therapy , Mevalonate Kinase Deficiency/drug therapy , Mevalonate Kinase Deficiency/etiology , Registries
3.
J Control Release ; 367: 385-401, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38253203

ABSTRACT

The availability of analytical methods for the characterization of lipid nanoparticles (LNPs) for in-vivo intracellular delivery of nucleic acids is critical for the fast development of innovative RNA therapies. In this study, analytical protocols to measure (i) chemical composition, (ii) drug loading, (iii) particle size, concentration, and stability as well as (iv) structure and morphology were evaluated and compared based on a comprehensive characterization strategy linking key physical and chemical properties to in-vitro efficacy and toxicity. Furthermore, the measurement protocols were assessed either by testing the reproducibility and robustness of the same technique in different laboratories, or by a correlative approach, comparing measurement results of the same attribute with orthogonal techniques. The characterization strategy and the analytical measurements described here will have an important role during formulation development and in determining robust quality attributes ultimately supporting the quality assessment of these innovative RNA therapeutics.


Subject(s)
Nanoparticles , Nucleic Acids , Reproducibility of Results , Lipids/chemistry , RNA, Small Interfering/genetics , Nanoparticles/chemistry , Liposomes , Particle Size
4.
Mol Cell Proteomics ; 23(2): 100713, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38184013

ABSTRACT

Optimizing data-independent acquisition methods for proteomics applications often requires balancing spectral resolution and acquisition speed. Here, we describe a real-time full mass range implementation of the phase-constrained spectrum deconvolution method (ΦSDM) for Orbitrap mass spectrometry that increases mass resolving power without increasing scan time. Comparing its performance to the standard enhanced Fourier transformation signal processing revealed that the increased resolving power of ΦSDM is beneficial in areas of high peptide density and comes with a greater ability to resolve low-abundance signals. In a standard 2 h analysis of a 200 ng HeLa digest, this resulted in an increase of 16% in the number of quantified peptides. As the acquisition speed becomes even more important when using fast chromatographic gradients, we further applied ΦSDM methods to a range of shorter gradient lengths (21, 12, and 5 min). While ΦSDM improved identification rates and spectral quality in all tested gradients, it proved particularly advantageous for the 5 min gradient. Here, the number of identified protein groups and peptides increased by >15% in comparison to enhanced Fourier transformation processing. In conclusion, ΦSDM is an alternative signal processing algorithm for processing Orbitrap data that can improve spectral quality and benefit quantitative accuracy in typical proteomics experiments, especially when using short gradients.


Subject(s)
Proteome , Tandem Mass Spectrometry , Humans , Proteome/metabolism , Tandem Mass Spectrometry/methods , Peptides/analysis , HeLa Cells , Proteomics/methods
5.
Phys Rev Lett ; 131(22): 220201, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38101372

ABSTRACT

From a thermodynamic point of view, all clocks are driven by irreversible processes. Additionally, one can use oscillatory systems to temporally modulate the thermodynamic flux towards equilibrium. Focusing on the most elementary thermalization events, this modulation can be thought of as a temporal probability concentration for these events. There are two fundamental factors limiting the performance of clocks: On the one level, the inevitable drifts of the oscillatory system, which are addressed by finding stable atomic or nuclear transitions that lead to astounding precision of today's clocks. On the other level, there is the intrinsically stochastic nature of the irreversible events upon which the clock's operation is based. This becomes relevant when seeking to maximize a clock's resolution at high accuracy, which is ultimately limited by the number of such stochastic events per reference time unit. We address this essential trade-off between clock accuracy and resolution, proving a universal bound for all clocks whose elementary thermalization events are memoryless.

6.
Eur J Health Econ ; 2023 Dec 15.
Article in English | MEDLINE | ID: mdl-38102524

ABSTRACT

PURPOSE: The calculation of aggregated composite measures is a widely used strategy to reduce the amount of data on hospital report cards. Therefore, this study aims to elicit and compare preferences of both patients as well as referring physicians regarding publicly available hospital quality information METHODS: Based on systematic literature reviews as well as qualitative analysis, two discrete choice experiments (DCEs) were applied to elicit patients' and referring physicians' preferences. The DCEs were conducted using a fractional factorial design. Statistical data analysis was performed using multinomial logit models RESULTS: Apart from five identical attributes, one specific attribute was identified for each study group, respectively. Overall, 322 patients (mean age 68.99) and 187 referring physicians (mean age 53.60) were included. Our models displayed significant coefficients for all attributes (p < 0.001 each). Among patients, "Postoperative complication rate" (20.6%; level range of 1.164) was rated highest, followed by "Mobility at hospital discharge" (19.9%; level range of 1.127), and ''The number of cases treated" (18.5%; level range of 1.045). In contrast, referring physicians valued most the ''One-year revision surgery rate'' (30.4%; level range of 1.989), followed by "The number of cases treated" (21.0%; level range of 1.372), and "Postoperative complication rate" (17.2%; level range of 1.123) CONCLUSION: We determined considerable differences between both study groups when calculating the relative value of publicly available hospital quality information. This may have an impact when calculating aggregated composite measures based on consumer-based weighting.

7.
Phys Rev Lett ; 131(16): 160204, 2023 Oct 20.
Article in English | MEDLINE | ID: mdl-37925703

ABSTRACT

In order to unitarily evolve a quantum system, an agent requires knowledge of time, a parameter that no physical clock can ever perfectly characterize. In this Letter, we study how limitations on acquiring knowledge of time impact controlled quantum operations in different paradigms. We show that the quality of timekeeping an agent has access to limits the circuit complexity they are able to achieve within circuit-based quantum computation. We do this by deriving an upper bound on the average gate fidelity achievable under imperfect timekeeping for a general class of random circuits. Another area where quantum control is relevant is quantum thermodynamics. In that context, we show that cooling a qubit can be achieved using a timer of arbitrary quality for control: timekeeping error only impacts the rate of cooling and not the achievable temperature. Our analysis combines techniques from the study of autonomous quantum clocks and the theory of quantum channels to understand the effect of imperfect timekeeping on controlled quantum dynamics.

8.
Nature ; 624(7990): 192-200, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37968396

ABSTRACT

Cellular functions are mediated by protein-protein interactions, and mapping the interactome provides fundamental insights into biological systems. Affinity purification coupled to mass spectrometry is an ideal tool for such mapping, but it has been difficult to identify low copy number complexes, membrane complexes and complexes that are disrupted by protein tagging. As a result, our current knowledge of the interactome is far from complete, and assessing the reliability of reported interactions is challenging. Here we develop a sensitive high-throughput method using highly reproducible affinity enrichment coupled to mass spectrometry combined with a quantitative two-dimensional analysis strategy to comprehensively map the interactome of Saccharomyces cerevisiae. Thousand-fold reduced volumes in 96-well format enabled replicate analysis of the endogenous GFP-tagged library covering the entire expressed yeast proteome1. The 4,159 pull-downs generated a highly structured network of 3,927 proteins connected by 31,004 interactions, doubling the number of proteins and tripling the number of reliable interactions compared with existing interactome maps2. This includes very-low-abundance epigenetic complexes, organellar membrane complexes and non-taggable complexes inferred by abundance correlation. This nearly saturated interactome reveals that the vast majority of yeast proteins are highly connected, with an average of 16 interactors. Similar to social networks between humans, the average shortest distance between proteins is 4.2 interactions. AlphaFold-Multimer provided novel insights into the functional roles of previously uncharacterized proteins in complexes. Our web portal ( www.yeast-interactome.org ) enables extensive exploration of the interactome dataset.


Subject(s)
Protein Interaction Mapping , Protein Interaction Maps , Proteome , Saccharomyces cerevisiae Proteins , Saccharomyces cerevisiae , Mass Spectrometry , Protein Interaction Mapping/methods , Proteome/chemistry , Proteome/metabolism , Reproducibility of Results , Saccharomyces cerevisiae/chemistry , Saccharomyces cerevisiae/metabolism , Saccharomyces cerevisiae Proteins/chemistry , Saccharomyces cerevisiae Proteins/metabolism , Epigenesis, Genetic , Databases, Factual
9.
Anal Bioanal Chem ; 415(27): 6633-6645, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37758903

ABSTRACT

Recent advances have rekindled the interest in ion mobility as an additional dimension of separation in mass spectrometry (MS)-based proteomics. Ion mobility separates ions according to their size and shape in the gas phase. Here, we set out to investigate the effect of 22 different post-translational modifications (PTMs) on the collision cross section (CCS) of peptides. In total, we analyzed ~4300 pairs of matching modified and unmodified peptide ion species by trapped ion mobility spectrometry (TIMS). Linear alignment based on spike-in reference peptides resulted in highly reproducible CCS values with a median coefficient of variation of 0.26%. On a global level, we observed a redistribution in the m/z vs. ion mobility space for modified peptides upon changes in their charge state. Pairwise comparison between modified and unmodified peptides of the same charge state revealed median shifts in CCS between -1.4% (arginine citrullination) and +4.5% (O-GlcNAcylation). In general, increasing modified peptide masses were correlated with higher CCS values, in particular within homologous PTM series. However, investigating the ion populations in more detail, we found that the change in CCS can vary substantially for a given PTM and is partially correlated with the gas phase structure of its unmodified counterpart. In conclusion, our study shows PTM- and sequence-specific effects on the cross section of peptides, which could be further leveraged for proteome-wide PTM analysis.


Subject(s)
Peptides , Proteomics , Peptides/chemistry , Mass Spectrometry/methods , Proteome , Protein Processing, Post-Translational , Ions/chemistry
10.
Sci Rep ; 13(1): 15764, 2023 09 22.
Article in English | MEDLINE | ID: mdl-37737457

ABSTRACT

We present a generically applicable approach to determine an extensive set of size-dependent critical quality attributes inside nanoparticulate pharmaceutical products. By coupling asymmetrical-flow field-flow fractionation (AF4) measurements directly in-line with solution small angle X-ray scattering (SAXS), vital information such as (i) quantitative, absolute size distribution profiles, (ii) drug loading, (iii) size-dependent internal structures, and (iv) quantitative information on free drug is obtained. Here the validity of the method was demonstrated by characterizing complex mRNA-based lipid nanoparticle products. The approach is particularly applicable to particles in the size range of 100 nm and below, which is highly relevant for pharmaceutical products-both biologics and nanoparticles. The method can be applied as well in other fields, including structural biology and environmental sciences.


Subject(s)
Nanoparticles , Scattering, Small Angle , X-Ray Diffraction , X-Rays , RNA, Messenger/genetics
11.
J Am Soc Mass Spectrom ; 34(10): 2232-2246, 2023 Oct 04.
Article in English | MEDLINE | ID: mdl-37638640

ABSTRACT

"Top-down" proteomics analyzes intact proteins and identifies proteoforms by their intact mass as well as the observed fragmentation pattern in tandem mass spectrometry (MS/MS) experiments. Recently, hybrid ion mobility spectrometry-mass spectrometry (IM/MS) methods have gained traction for top-down experiments, either by allowing top-down analysis of individual isomers or alternatively by improving signal/noise and dynamic range for fragment ion assignment. We recently described the construction of a tandem-trapped ion mobility spectrometer/mass spectrometer (tandem-TIMS/MS) coupled with an ultraviolet (UV) laser and demonstrated a proof-of-principle for top-down analysis by UV photodissociation (UVPD) at 2-3 mbar. The present work builds on this with an exploration of a top-down method that couples tandem-TIMS/MS with UVPD and parallel-accumulation serial fragmentation (PASEF) MS/MS analysis. We first survey types and structures of UVPD-specific fragment ions generated in the 2-3 mbar pressure regime of our instrument. Notably, we observe UVPD-induced fragment ions with multiple conformations that differ from those produced in the absence of UV irradiation. Subsequently, we discuss how MS/MS spectra of top-down fragment ions lend themselves ideally for probability-based scoring methods developed in the bottom-up proteomics field and how the ability to record automated PASEF-MS/MS spectra resolves ambiguities in the assignment of top-down fragment ions. Finally, we describe the coupling of tandem-TIMS/MS workflows with UVPD and PASEF-MS/MS analysis for native top-down protein analysis.


Subject(s)
Ion Mobility Spectrometry , Tandem Mass Spectrometry , Tandem Mass Spectrometry/methods , Proteins/analysis , Ions , Ultraviolet Rays
12.
Anal Chem ; 95(19): 7487-7494, 2023 05 16.
Article in English | MEDLINE | ID: mdl-37146101

ABSTRACT

We report an online analytical platform based on the coupling of asymmetrical flow field-flow fractionation (AF4) and native mass spectrometry (nMS) in parallel with UV-absorbance, multi-angle light scattering (MALS), and differential-refractive-index (UV-MALS-dRI) detectors to elucidate labile higher-order structures (HOS) of protein biotherapeutics. The technical aspects of coupling AF4 with nMS and the UV-MALS-dRI multi-detection system are discussed. The "slot-outlet" technique was used to reduce sample dilution and split the AF4 effluent between the MS and UV-MALS-dRI detectors. The stability, HOS, and dissociation pathways of the tetrameric biotherapeutic enzyme (anticancer agent) l-asparaginase (ASNase) were studied. ASNase is a 140 kDa homo-tetramer, but the presence of intact octamers and degradation products with lower molecular weights was indicated by AF4-MALS/nMS. Exposing ASNase to 10 mM NaOH disturbed the equilibrium between the different non-covalent species and led to HOS dissociation. Correlation of the information obtained by AF4-MALS (liquid phase) and AF4-nMS (gas phase) revealed the formation of monomeric, tetrameric, and pentameric species. High-resolution MS revealed deamidation of the main intact tetramer upon exposure of ASNase to high pH (NaOH and ammonium bicarbonate). The particular information retrieved from ASNase with the developed platform in a single run demonstrates that the newly developed platform can be highly useful for aggregation and stability studies of protein biopharmaceuticals.


Subject(s)
Fractionation, Field Flow , Proteins , Sodium Hydroxide , Mass Spectrometry , Refractometry , Asparaginase , Fractionation, Field Flow/methods
13.
Anal Bioanal Chem ; 415(15): 3007-3031, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37106123

ABSTRACT

A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)-multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC-MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies. Particle sizes and number-based concentrations obtained by orthogonal batch methods (DLS, NTA, TRPS) were comparable for monodisperse spherical samples, while higher deviations were observed for polydisperse, agglomerated samples and for non-spherical particles, especially for light scattering methods. CLS and TRPS offer further insight with increased size resolution, while detailed morphological information can be derived by electron microscopy (EM)-based approaches. Combined techniques such as FFF coupled to MALS and RM can provide complementary information on physical and chemical properties by online measurements, while pyGC-MS analysis of FFF fractions can be used for the identification of polymer particles (vs. inorganic particles) and for their offline (semi)quantification. However, NPL analysis in complex samples will continue to present a serious challenge for the evaluated techniques without significant improvements in sample preparation.

14.
Z Rheumatol ; 82(4): 269-277, 2023 May.
Article in German | MEDLINE | ID: mdl-37099181

ABSTRACT

The major tasks of the immune system are protection against infectious agents, maintaining homeostasis by recognizing and neutralizing noxious substances from the environment, and monitoring pathological, e.g. neoplastic tissue changes. It accomplishes these tasks through complex interactions of cellular and humoral components of the innate and adaptive immune system. This review article focuses on a central problem of self versus non-self discrimination in the development of B and T lymphocytes as carriers of adaptive immunity. During maturation of the lymphocytes in the bone marrow, large repertoires of lymphocyte receptors are randomly generated by somatic recombination, which as a whole have the capability of recognizing any foreign antigen. In order to reduce the implicit risk of autoaggressive immunity that might arise from evolutionary conserved structural motifs in self and foreign antigens, the adaptive immune system must provide redundant mechanisms (clonal deletion, anergy, quiescence and suppression) to eliminate or inactivate lymphocytes expressing highly avid receptors for autoantigens. Thus, the provision of costimulatory signals resulting in a reduced activation threshold of potentially autoreactive anergic T cells through infection, molecular mimicry, disrupted apoptosis regulation, altered "self" by post-translational modification, genetic changes in transcription factors with critical importance for thymic tolerance induction or signaling components of apoptosis can lead to a disruption of self-tolerance and the induction of pathogenic autoimmunity.


Subject(s)
Autoimmune Diseases , Rheumatic Diseases , Humans , Immune Tolerance , T-Lymphocytes , Self Tolerance , Autoimmunity , Autoantigens
15.
Small ; 19(23): e2207207, 2023 06.
Article in English | MEDLINE | ID: mdl-36922728

ABSTRACT

In this study, a 96-well exposure system for safety assessment of nanomaterials is developed and characterized using an air-liquid interface lung epithelial model. This system is designed for sequential nebulization. Distribution studies verify the reproducible distribution over all 96 wells, with lower insert-to-insert variability compared to non-sequential application. With a first set of chemicals (TritonX), drugs (Bortezomib), and nanomaterials (silver nanoparticles and (non-)fluorescent crystalline nanocellulose), sequential exposure studies are performed with human lung epithelial cells followed by quantification of the deposited mass and of cell viability. The developed exposure system offers for the first time the possibility of exposing an air-liquid interface model in a 96-well format, resulting in high-throughput rates, combined with the feature for sequential dosing. This exposure system allows the possibility of creating dose-response curves resulting in the generation of more reliable cell-based assay data for many types of applications, such as safety analysis. In addition to chemicals and drugs, nanomaterials with spherical shapes, but also morphologically more complex nanostructures can be exposed sequentially with high efficiency. This allows new perspectives on in vivo-like and animal-free approaches for chemical and pharmaceutical safety assessment, in line with the 3R principle of replacing and reducing animal experiments.


Subject(s)
Metal Nanoparticles , Humans , Silver , Lung , Epithelial Cells , Bortezomib
16.
Mol Cell Proteomics ; 22(2): 100489, 2023 02.
Article in English | MEDLINE | ID: mdl-36566012

ABSTRACT

Data-independent acquisition (DIA) methods have become increasingly popular in mass spectrometry-based proteomics because they enable continuous acquisition of fragment spectra for all precursors simultaneously. However, these advantages come with the challenge of correctly reconstructing the precursor-fragment relationships in these highly convoluted spectra for reliable identification and quantification. Here, we introduce a scan mode for the combination of trapped ion mobility spectrometry with parallel accumulation-serial fragmentation (PASEF) that seamlessly and continuously follows the natural shape of the ion cloud in ion mobility and peptide precursor mass dimensions. Termed synchro-PASEF, it increases the detected fragment ion current several-fold at sub-second cycle times. Consecutive quadrupole selection windows move synchronously through the mass and ion mobility range. In this process, the quadrupole slices through the peptide precursors, which separates fragment ion signals of each precursor into adjacent synchro-PASEF scans. This precisely defines precursor-fragment relationships in ion mobility and mass dimensions and effectively deconvolutes the DIA fragment space. Importantly, the partitioned parts of the fragment ion transitions provide a further dimension of specificity via a lock-and-key mechanism. This is also advantageous for quantification, where signals from interfering precursors in the DIA selection window do not affect all partitions of the fragment ion, allowing to retain only the specific parts for quantification. Overall, we establish the defining features of synchro-PASEF and explore its potential for proteomic analyses.


Subject(s)
Proteomics , Tandem Mass Spectrometry , Tandem Mass Spectrometry/methods , Proteomics/methods , Proteome/analysis , Peptides/analysis
17.
Proteomics ; 23(7-8): e2200032, 2023 04.
Article in English | MEDLINE | ID: mdl-36300730

ABSTRACT

Mass spectrometry-based phosphoproteomics has identified >150,000 post-translational phosphorylation sites in the human proteome. To disentangle their functional relevance, complex experimental designs that require increased throughput are now coming into focus. Here, we apply dia-PASEF on a trapped ion mobility (TIMS) mass spectrometer to analyze the phosphoproteome of a human cancer cell line in short liquid chromatography gradients. At low sample amounts equivalent to ∼20 ug protein digest per analysis, we quantified over 13,000 phosphopeptides including ∼8700 class I phosphosites in 1 h without a spectral library. Decreasing the gradient time to 15 min yielded virtually identical coverage of the phosphoproteome, and with 7 min gradients we still quantified about 80% of the class I sites with a median coefficient of variation <10% in quadruplicates. We attribute this in part to the increased peak capacity, which effectively compensates for the higher peptide density per time unit in shorter gradients. Our data show a five-fold reduction in the number of co-isolated peptides with TIMS. In the most extreme case, these were positional isomers of nearby phosphosites that remained unresolved with fast liquid chromatography. In summary, our study demonstrates how key features of dia-PASEF translate to phosphoproteomics.


Subject(s)
Phosphopeptides , Proteome , Humans , Phosphopeptides/analysis , Chromatography, Liquid/methods , Mass Spectrometry/methods , Proteome/analysis , Cell Line
18.
J Clin Med ; 11(21)2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36362620

ABSTRACT

Drug-related problems (e.g., adverse drug reactions, ADR) are serious safety issues in patients treated with oral anticancer therapeutics (OAT). The previously published randomized AMBORA trial showed that an intensified clinical pharmacological/pharmaceutical care program within the first 12 weeks of treatment reduces the number and severity of ADR as well as hospitalization rates in 202 patients. The present investigation focused on unscheduled hospitalizations detected within AMBORA and analyzed the characteristics (e.g., frequency, involved OAT) and cost of each hospital stay. To estimate the potential savings of an intensified care program in a larger group, the absolute risk for OAT-related hospitalizations was extrapolated to all insureds of a leading German statutory health insurance company (AOK Bayern). Within 12 weeks, 45 of 202 patients were hospitalized. 50% of all unscheduled hospital admissions were OAT-related (20 of 40) and occurred in 18 patients. The mean cost per inpatient stay was EUR 5873. The intensified AMBORA care program reduced the patients' absolute risk for OAT-related hospitalization by 11.36%. If this care program would have been implemented in the AOK Bayern collective (3,862,017 insureds) it has the potential to reduce hospitalization rates and thereby cost by a maximum of EUR 4.745 million within 12 weeks after therapy initiation.

20.
Mol Cell Proteomics ; 21(9): 100279, 2022 09.
Article in English | MEDLINE | ID: mdl-35944843

ABSTRACT

Data-independent acquisition (DIA) methods have become increasingly attractive in mass spectrometry-based proteomics because they enable high data completeness and a wide dynamic range. Recently, we combined DIA with parallel accumulation-serial fragmentation (dia-PASEF) on a Bruker trapped ion mobility (IM) separated quadrupole time-of-flight mass spectrometer. This requires alignment of the IM separation with the downstream mass selective quadrupole, leading to a more complex scheme for dia-PASEF window placement compared with DIA. To achieve high data completeness and deep proteome coverage, here we employ variable isolation windows that are placed optimally depending on precursor density in the m/z and IM plane. This is implemented in the freely available py_diAID (Python package for DIA with an automated isolation design) package. In combination with in-depth project-specific proteomics libraries and the Evosep liquid chromatography system, we reproducibly identified over 7700 proteins in a human cancer cell line in 44 min with quadruplicate single-shot injections at high sensitivity. Even at a throughput of 100 samples per day (11 min liquid chromatography gradients), we consistently quantified more than 6000 proteins in mammalian cell lysates by injecting four replicates. We found that optimal dia-PASEF window placement facilitates in-depth phosphoproteomics with very high sensitivity, quantifying more than 35,000 phosphosites in a human cancer cell line stimulated with an epidermal growth factor in triplicate 21 min runs. This covers a substantial part of the regulated phosphoproteome with high sensitivity, opening up for extensive systems-biological studies.


Subject(s)
Proteome , Tandem Mass Spectrometry , Animals , Chromatography, Liquid/methods , Epidermal Growth Factor , Humans , Mammals/metabolism , Proteome/metabolism , Proteomics/methods , Tandem Mass Spectrometry/methods
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