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Fiala J, Schuster D, Ollivier S, Pengelley S, Lubeck M, Busch F, Jankevics A, Raether O, Greisch JF, Heck AJR. Protein-Centric Analysis of Personalized Antibody Repertoires Using LC-MS-Based Fab-Profiling on a timsTOF. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2024; 35:1292-1300. [PMID: 38662593 PMCID: PMC11157643 DOI: 10.1021/jasms.4c00076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2024] [Revised: 04/15/2024] [Accepted: 04/17/2024] [Indexed: 06/06/2024]
Abstract
Endogenous antibodies, or immunoglobulins (Igs), abundantly present in body fluids, represent some of the most challenging samples to analyze, largely due to the immense variability in their sequences and concentrations. It has been estimated that our body can produce billions of different Ig proteins with different isotypes, making their individual analysis seemingly impossible. However, recent advances in protein-centric proteomics using LC-MS coupled to Orbitrap mass analyzers to profile intact Fab fragments formed by selective cleavage at the IgG-hinge revealed that IgG repertoires may be less diverse, albeit unique for each donor. Serum repertoires seem to be dominated by a few hundred clones that cumulatively make up 50-95% of the total IgG content. Enabling such analyses required careful optimization of the chromatography and mass analysis, as all Fab analytes are highly alike in mass (46-51 kDa) and sequence. To extend the opportunities of this mass-spectrometry-based profiling of antibody repertoires, we here report the optimization and evaluation of an alternative MS platform, namely, the timsTOF, for antibody repertoire profiling. The timsTOF mass analyzer has gained traction in recent years for peptide-centric proteomics and found wide applicability in plasma proteomics, affinity proteomics, and HLA peptidomics, to name a few. However, for protein-centric analysis, this platform has been less explored. Here, we demonstrate that the timsTOF platform can be adapted to perform protein-centric LC-MS-based profiling of antibody repertoires. In a side-by-side comparison of the timsTOF and the Orbitrap we demonstrate that the extracted serum antibody repertoires are alike qualitatively and quantitatively, whereby in particular the sensitivity of the timsTOF platform excels. Future incorporation of advanced top-down capabilities on the timsTOF may make this platform a very valuable alternative for protein-centric proteomics and top-down proteomics and thus also for personalized antibody repertoire profiling.
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Affiliation(s)
- Jan Fiala
- Biomolecular
Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular
Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584
CH Utrecht, The
Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Dina Schuster
- Biomolecular
Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular
Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584
CH Utrecht, The
Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Simon Ollivier
- Biomolecular
Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular
Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584
CH Utrecht, The
Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Stuart Pengelley
- Bruker
Daltonics GmbH & Co. KG, Fahrenheitstrasse 4, 28359 Bremen, Germany
| | - Markus Lubeck
- Bruker
Daltonics GmbH & Co. KG, Fahrenheitstrasse 4, 28359 Bremen, Germany
| | - Florian Busch
- Bruker
Switzerland AG, 8117 Fällanden, Zurich Switzerland
| | - Andris Jankevics
- Biomolecular
Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular
Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584
CH Utrecht, The
Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
| | - Oliver Raether
- Bruker
Daltonics GmbH & Co. KG, Fahrenheitstrasse 4, 28359 Bremen, Germany
| | | | - Albert J. R. Heck
- Biomolecular
Mass Spectrometry & Proteomics, Bijvoet Center for Biomolecular
Research & Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Padualaan 8, 3584
CH Utrecht, The
Netherlands
- Netherlands
Proteomics Center, Padualaan
8, 3584 CH Utrecht, The Netherlands
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Ramirez-Sagredo A, Sunny A, Cupp-Sutton K, Chowdhury T, Zhao Z, Wu S, Ann Chiao Y. Characterizing Age-related Changes in Intact Mitochondrial Proteoforms in Murine Hearts using Quantitative Top-Down Proteomics. RESEARCH SQUARE 2024:rs.3.rs-3868218. [PMID: 38313302 PMCID: PMC10836115 DOI: 10.21203/rs.3.rs-3868218/v1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2024]
Abstract
Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and the prevalence of CVDs increases markedly with age. Due to the high energetic demand, the heart is highly sensitive to mitochondrial dysfunction. The complexity of the cardiac mitochondrial proteome hinders the development of effective strategies that target mitochondrial dysfunction in CVDs. Mammalian mitochondria are composed of over 1000 proteins, most of which can undergo post-translational protein modifications (PTMs). Top-down proteomics is a powerful technique for characterizing and quantifying all protein sequence variations and PTMs. However, there are still knowledge gaps in the study of age-related mitochondrial proteoform changes using this technique. In this study, we used top-down proteomics to identify intact mitochondrial proteoforms in young and old hearts and determined changes in protein abundance and PTMs in cardiac aging. METHODS Intact mitochondria were isolated from the hearts of young (4-month-old) and old (24-25-month-old) mice. The mitochondria were lysed, and mitochondrial lysates were subjected to denaturation, reduction, and alkylation. For quantitative top-down analysis, there were 12 runs in total arising from 3 biological replicates in two conditions, with technical duplicates for each sample. The collected top-down datasets were deconvoluted and quantified, and then the proteoforms were identified. RESULTS From a total of 12 LC-MS/MS runs, we identified 134 unique mitochondrial proteins in the different sub-mitochondrial compartments (OMM, IMS, IMM, matrix). 823 unique proteoforms in different mass ranges were identified. Compared to cardiac mitochondria of young mice, 7 proteoforms exhibited increased abundance and 13 proteoforms exhibited decreased abundance in cardiac mitochondria of old mice. Our analysis also detected PTMs of mitochondrial proteoforms, including N-terminal acetylation, lysine succinylation, lysine acetylation, oxidation, and phosphorylation. CONCLUSION By combining mitochondrial protein enrichment using mitochondrial fractionation with quantitative top-down analysis using ultrahigh-pressure liquid chromatography (UPLC)-MS and label-free quantitation, we successfully identified and quantified intact proteoforms in the complex mitochondrial proteome. Using this approach, we detected age-related changes in abundance and PTMs of mitochondrial proteoforms in the heart.
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Kline JT, Melani RD, Fornelli L. Mass spectrometry characterization of antibodies at the intact and subunit levels: from targeted to large-scale analysis. INTERNATIONAL JOURNAL OF MASS SPECTROMETRY 2023; 492:117117. [PMID: 38855125 PMCID: PMC11160972 DOI: 10.1016/j.ijms.2023.117117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2024]
Abstract
Antibodies are one of the most formidable molecular weapons available to our immune system. Their high specificity against a target (antigen) and capability of triggering different immune responses (e.g., complement system activation and antibody-dependent cell-mediated cytotoxicity) make them ideal drugs to fight many different human diseases. Currently, both monoclonal antibodies and more complex molecules based on the antibody scaffold are used as biologics. Naturally, such highly heterogeneous molecules require dedicated analytical methodologies for their accurate characterization. Mass spectrometry (MS) can define the presence and relative abundance of multiple features of antibodies, including critical quality attributes. The combination of small and large variations within a single molecule can only be determined by analyzing intact antibodies or their large (25 to 100 kDa) subunits. Hence, top-down (TD) and middle-down (MD) MS approaches have gained popularity over the last decade. In this Young Scientist Feature we discuss the evolution of TD and MD MS analysis of antibodies, including the new frontiers that go beyond biopharma applications. We will show how this field is now moving from the "quality control" analysis of a known, single antibody to the high-throughput investigation of complex antibody repertoires isolated from clinical samples, where the ultimate goal is represented by the complete gas-phase sequencing of antibody molecules without the need of any a priori knowledge.
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Affiliation(s)
- Jake T. Kline
- Department of Biology, University of Oklahoma, Norman, Oklahoma 73019, United States
| | - Rafael D. Melani
- Thermo Fisher Scientific, San Jose, California 95134, United States
| | - Luca Fornelli
- Department of Biology, University of Oklahoma, Norman, Oklahoma 73019, United States
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, Oklahoma 73019, United States
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Kazieva LS, Farafonova TE, Zgoda VG. [Antibody proteomics]. BIOMEDITSINSKAIA KHIMIIA 2023; 69:5-18. [PMID: 36857423 DOI: 10.18097/pbmc20236901005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/02/2023]
Abstract
Antibodies represent an essential component of humoral immunity; therefore their study is important for molecular biology and medicine. The unique property of antibodies to specifically recognize and bind a certain molecular target (an antigen) determines their widespread application in treatment and diagnostics of diseases, as well as in laboratory and biotechnological practices. High specificity and affinity of antibodies is determined by the presence of primary structure variable regions, which are not encoded in the human genome and are unique for each antibody-producing B cell clone. Hence, there is little or no information about amino acid sequences of the variable regions in the databases. This differs identification of antibody primary structure from most of the proteomic studies because it requires either B cell genome sequencing or de novo amino acid sequencing of the antibody. The present review demonstrates some examples of proteomic and proteogenomic approaches and the methodological arsenal that proteomics can offer for studying antibodies, in particular, for identification of primary structure, evaluation of posttranslational modifications and application of bioinformatics tools for their decoding.
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Affiliation(s)
- L Sh Kazieva
- Institute of Biomedical Chemistry, Moscow, Russia
| | | | - V G Zgoda
- Institute of Biomedical Chemistry, Moscow, Russia
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5
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Turner CN, Mullins GN, Hoyer KK. CXCR5 +CD8 T cells: Potential immunotherapy targets or drivers of immune-mediated adverse events? Front Med (Lausanne) 2022; 9:1034764. [PMID: 36314014 PMCID: PMC9606409 DOI: 10.3389/fmed.2022.1034764] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 09/23/2022] [Indexed: 11/15/2022] Open
Abstract
CXCR5+CD8 T cells have attracted significant interest within multiple areas of immunology, cancer, and infection. This is in part due to their apparent dual functionality. These cells perform as cytotoxic cells in a variety of infection states including LCMV, HBV, HIV and SIV. However, CXCR5+CD8 T cells also associate with B cells in peripheral organs and function to stimulate B cell proliferation, antibody/B cell receptor class-switch, and antibody production. CXCR5+CD8 T cells are similar to CXCR5+CD4 T follicular helpers in their genetic make-up, B cell interactions, and functionality despite possessing elevated programmed cell death 1 and cytotoxic proteins. Within cancer CXCR5+CD8 T cells have risen as potential prognostic markers for overall survival and are functionally cytotoxic within tumor microenvironments. In inflammatory disease and autoimmunity, CXCR5+CD8 T cells are implicated in disease progression. During viral infection and cancer, CXCR5 expression on CD8 T cells generally is indicative of progenitor memory stem-like exhausted cells, which are more responsive to immune checkpoint blockade therapy. The use of immune checkpoint inhibitors to overcome immune exhaustion in cancer, and subsequent consequence of immune adverse events, highlights the dual nature of the cellular immune response. This review will detail the functionality of CXCR5+CD8 T cells in cancer and autoimmunity with potential repercussions during immune checkpoint blockade therapy discussed.
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Affiliation(s)
- Christi N. Turner
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States
| | - Genevieve N. Mullins
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States
| | - Katrina K. Hoyer
- Quantitative and Systems Biology Graduate Program, University of California, Merced, Merced, CA, United States,Department of Molecular and Cell Biology, School of Natural Sciences, University of California, Merced, Merced, CA, United States,Health Sciences Research Institute, University of California, Merced, Merced, CA, United States,*Correspondence: Katrina K. Hoyer
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6
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Guo Y, Yu D, Cupp-Sutton KA, Liu X, Wu S. A benchmarking protocol for intact protein-level Tandem Mass Tag (TMT) labeling for quantitative top-down proteomics. MethodsX 2022; 9:101873. [PMID: 36281278 PMCID: PMC9587358 DOI: 10.1016/j.mex.2022.101873] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 09/27/2022] [Indexed: 11/06/2022] Open
Abstract
Isobaric chemical tag labeling for quantification of intact proteins in complex samples is limited due to the tendency of intact proteins precipitate under labeling conditions and increased sample complexity as a result of side products (i.e., incomplete labeling or labeling of unintended residues). To reduce precipitation under labeling conditions, we developed a technique to remove large proteoforms that allowed for the labeling and characterization of small proteoforms (<35 kDa) using top-down proteomics. We also systematically optimized protein-level Tandem Mass Tag (TMT) labeling conditions to obtain optimal labeling parameters for complex samples. Here, we present a benchmarking protocol for protein-level TMT labeling for quantitative top-down proteomics, including complex intact protein sample preparation, protein-level TMT labeling, top-down LC/MS analysis, and TMT reporter ion quantification.An optimized protocol for protein-level TMT labeling in complex sample. Limits production of incorrectly labeled side products for minimization of spectral complexity. A guideline for isobaric chemical tag quantification in top-down proteomics.
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Affiliation(s)
- Yanting Guo
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK 73019, United States
| | - Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK 73019, United States
| | - Kellye A. Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK 73019, United States
| | - Xiaowen Liu
- John W. Deming Department of Medicine, Tulane University School of Medicine, New Orleans Bioinnovation Center, Room 422, United States
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK 73019, United States
- Corresponding author.
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7
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Wang C, Liang Y, Zhao B, Liang Z, Zhang L, Zhang Y. Ethane-Bridged Hybrid Monolithic Column with Large Mesopores for Boosting Top-Down Proteomic Analysis. Anal Chem 2022; 94:6172-6179. [PMID: 35412811 DOI: 10.1021/acs.analchem.1c05234] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Top-down proteomics is challenged by the high complexity of biological samples. The coelution of intact proteins results in overlapped mass spectra, and hence, an increased peak capacity for protein separation is needed. Herein, ethane-bridged hybrid monoliths with well-defined large mesopores were successfully prepared based on the sol-gel condensation of 1,2-bis(trimethoxysilyl)ethane and tetramethoxysilane, followed by two-step base etching of the Si-O-Si domain while maintaining the Si-C-C-Si domain in the structure. Relatively homogeneous macropores of 1.1 μm and large mesopores of 24 nm were obtained, permitting fast mass transfer of large molecules and efficient diffusion without obstruction. The use of less hydrophobic C1 ligand further sharpened the peak shape and improved peak capacity. A 120 cm-long capillary column was used for top-down proteomic analysis of E. coli lysates under low backpressure with 16 MPa. High peak capacity of 646 was achieved within 240 min gradient. With MS/MS analysis, 959 proteoforms corresponding to 263 proteins could be unambiguously identified from E. coli lysates in a single run. Furthermore, to illustrate the separation performance for large proteoforms, such monoliths were applied to top-down analysis of the SEC fraction of E. coli lysates with Mw ranging from 30 to 70 kDa. With highly effective separation, 347 large proteoforms with Mw higher than 30 kDa were detected in the single 75 min run. These results showed great potential for top-down proteomic analysis in complex samples.
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Affiliation(s)
- Chao Wang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yu Liang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Baofeng Zhao
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Zhen Liang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Lihua Zhang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
| | - Yukui Zhang
- CAS Key Lab of Separation Sciences for Analytical Chemistry, National Chromatographic Research and Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China
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8
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de Graaf SC, Hoek M, Tamara S, Heck AJR. A perspective toward mass spectrometry-based de novo sequencing of endogenous antibodies. MAbs 2022; 14:2079449. [PMID: 35699511 PMCID: PMC9225641 DOI: 10.1080/19420862.2022.2079449] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
A key step in therapeutic and endogenous humoral antibody characterization is identifying the amino acid sequence. So far, this task has been mainly tackled through sequencing of B-cell receptor (BCR) repertoires at the nucleotide level. Mass spectrometry (MS) has emerged as an alternative tool for obtaining sequence information directly at the – most relevant – protein level. Although several MS methods are now well established, analysis of recombinant and endogenous antibodies comes with a specific set of challenges, requiring approaches beyond the conventional proteomics workflows. Here, we review the challenges in MS-based sequencing of both recombinant as well as endogenous humoral antibodies and outline state-of-the-art methods attempting to overcome these obstacles. We highlight recent examples and discuss remaining challenges. We foresee a great future for these approaches making de novo antibody sequencing and discovery by MS-based techniques feasible, even for complex clinical samples from endogenous sources such as serum and other liquid biopsies.
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Affiliation(s)
- Sebastiaan C de Graaf
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands.,Netherlands Proteomics Center, Utrecht, Netherlands
| | - Max Hoek
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands.,Netherlands Proteomics Center, Utrecht, Netherlands
| | - Sem Tamara
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands.,Netherlands Proteomics Center, Utrecht, Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Utrecht, Netherlands.,Netherlands Proteomics Center, Utrecht, Netherlands
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9
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Abstract
Top-down proteomics methods have a distinct advantage over bottom-up methods in that they analyze intact proteins rather than digested peptides which can result in loss of information regarding the intact protein. However, the analysis of intact proteins using top-down proteomics methods has been impeded by the low resolution of typical separation approaches applied in bottom-up proteomics studies. To increase the coverage of intact proteomes, orthogonal, two-dimensional separation techniques have been developed to improve the separation efficiency; in this chapter, we describe a two-dimensional HPLC separation technique that utilizes a high-pH mobile phase in the first dimension followed by a low-pH mobile phase in the second dimension. This two-dimensional pH-based HPLC approach demonstrates increased separation efficiency of intact proteins and increased proteome coverage when compared to one-dimensional HPLC in the analysis of larger and lower abundance proteoforms.
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Affiliation(s)
- Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA
| | - Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, USA.
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10
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Why current quantitative serology is not quantitative and how systems immunology could provide solutions. Biol Futur 2021; 72:37-44. [PMID: 34554503 PMCID: PMC7896550 DOI: 10.1007/s42977-020-00061-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Accepted: 12/21/2020] [Indexed: 12/26/2022]
Abstract
Determination of the presence of antibodies against infectious agents, self-antigens, allogeneic antigens and environmental antigens is the goal of medical serology. Along with the standardization of these tests the community also started to use the expression “quantitative serology,” referring to the fact that arbitrary units are used for the expression of results. In this review I will argue against the use of the term quantitative serology for current tests. Because each test and each antibody isotype determination uses its own references, the term semiquantitative better describes these methods. The introduction of really quantitative serology could both benefit from and drive forward systems immunological approach to immunity.
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11
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Progress and challenges in mass spectrometry-based analysis of antibody repertoires. Trends Biotechnol 2021; 40:463-481. [PMID: 34535228 DOI: 10.1016/j.tibtech.2021.08.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2021] [Revised: 08/16/2021] [Accepted: 08/17/2021] [Indexed: 12/22/2022]
Abstract
Humoral immunity is divided into the cellular B cell and protein-level antibody responses. High-throughput sequencing has advanced our understanding of both these fundamental aspects of B cell immunology as well as aspects pertaining to vaccine and therapeutics biotechnology. Although the protein-level serum and mucosal antibody repertoire make major contributions to humoral protection, the sequence composition and dynamics of antibody repertoires remain underexplored. This limits insight into important immunological and biotechnological parameters such as the number of antigen-specific antibodies, which are for example, relevant for pathogen neutralization, microbiota regulation, severity of autoimmunity, and therapeutic efficacy. High-resolution mass spectrometry (MS) has allowed initial insights into the antibody repertoire. We outline current challenges in MS-based sequence analysis of antibody repertoires and propose strategies for their resolution.
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12
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Bondt A, Hoek M, Tamara S, de Graaf B, Peng W, Schulte D, van Rijswijck DMH, den Boer MA, Greisch JF, Varkila MRJ, Snijder J, Cremer OL, Bonten MJM, Heck AJR. Human plasma IgG1 repertoires are simple, unique, and dynamic. Cell Syst 2021; 12:1131-1143.e5. [PMID: 34613904 PMCID: PMC8691384 DOI: 10.1016/j.cels.2021.08.008] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 06/29/2021] [Accepted: 08/19/2021] [Indexed: 01/30/2023]
Abstract
Although humans can produce billions of IgG1 variants through recombination and hypermutation, the diversity of IgG1 clones circulating in human blood plasma has largely eluded direct characterization. Here, we combined several mass-spectrometry-based approaches to reveal that the circulating IgG1 repertoire in human plasma is dominated by a limited number of clones in healthy donors and septic patients. We observe that each individual donor exhibits a unique serological IgG1 repertoire, which remains stable over time but can adapt rapidly to changes in physiology. We introduce an integrative protein- and peptide-centric approach to obtain and validate a full sequence of an individual plasma IgG1 clone de novo. This IgG1 clone emerged at the onset of a septic episode and exhibited a high mutation rate (13%) compared with the closest matching germline DNA sequence, highlighting the importance of de novo sequencing at the protein level. A record of this paper’s transparent peer review process is included in the supplemental information. Novel LC-MS-based methods enable personalized IgG1 profiling in plasma Each donor exhibits a simple but unique serological IgG1 repertoire This repertoire adapts to changes in physiology, e.g., sepsis Individual plasma IgG1 clones can be identified by combining top-down and bottom-up proteomics
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Affiliation(s)
- Albert Bondt
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Max Hoek
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Sem Tamara
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Bastiaan de Graaf
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Weiwei Peng
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Douwe Schulte
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Danique M H van Rijswijck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Maurits A den Boer
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Jean-François Greisch
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Meri R J Varkila
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Joost Snijder
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands
| | - Olaf L Cremer
- Department of Intensive Care Medicine, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Marc J M Bonten
- Julius Center for Health Sciences and Primary Care, University Medical Center Utrecht, Utrecht, the Netherlands; Department of Medical Microbiology, University Medical Center Utrecht, Utrecht, the Netherlands
| | - Albert J R Heck
- Biomolecular Mass Spectrometry and Proteomics, Bijvoet Center for Biomolecular Research and Utrecht Institute for Pharmaceutical Sciences, University of Utrecht, Padualaan 8, Utrecht 3584 CH, the Netherlands; Netherlands Proteomics Center, Padualaan 8, Utrecht 3584 CH, the Netherlands.
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13
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Yu D, Wang Z, Cupp-Sutton KA, Guo Y, Kou Q, Smith K, Liu X, Wu S. Quantitative Top-Down Proteomics in Complex Samples Using Protein-Level Tandem Mass Tag Labeling. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1336-1344. [PMID: 33725447 PMCID: PMC8323476 DOI: 10.1021/jasms.0c00464] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Labeling approaches using isobaric chemical tags (e.g., isobaric tagging for relative and absolute quantification, iTRAQ and tandem mass tag, TMT) have been widely applied for the quantification of peptides and proteins in bottom-up MS. However, until recently, successful applications of these approaches to top-down proteomics have been limited because proteins tend to precipitate and "crash" out of solution during TMT labeling of complex samples making the quantification of such samples difficult. In this study, we report a top-down TMT MS platform for confidently identifying and quantifying low molecular weight intact proteoforms in complex biological samples. To reduce the sample complexity and remove large proteins from complex samples, we developed a filter-SEC technique that combines a molecular weight cutoff filtration step with high-performance size exclusion chromatography (SEC) separation. No protein precipitation was observed in filtered samples under the intact protein-level TMT labeling conditions. The proposed top-down TMT MS platform enables high-throughput analysis of intact proteoforms, allowing for the identification and quantification of hundreds of intact proteoforms from Escherichia coli cell lysates. To our knowledge, this represents the first high-throughput TMT labeling-based, quantitative, top-down MS analysis suitable for complex biological samples.
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Affiliation(s)
- Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Yanting Guo
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Qiang Kou
- School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Kenneth Smith
- Department of Arthritis and Clinical Immunology, Oklahoma Medical Research Foundation, Oklahoma City, Oklahoma 73104, United States
| | - Xiaowen Liu
- School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
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14
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Cejkov M, Greer T, Johnson RO, Zheng X, Li N. Electron Transfer Dissociation Parameter Optimization Using Design of Experiments Increases Sequence Coverage of Monoclonal Antibodies. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:762-771. [PMID: 33596068 DOI: 10.1021/jasms.0c00458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Middle-down analysis of monoclonal antibodies (mAbs) by tandem mass spectrometry (MS2) can provide detailed insight into their primary structure with minimal sample preparation. The middle-down approach uses an enzyme to cleave mAbs into Fc/2, LC, and Fd subunits that are then analyzed by reversed phase liquid chromatography tandem mass spectrometry (RPLC-MS2). As maximum sequence coverage is desired to obtain meaningful structural information at the subunit level, a host of dissociation methods have been developed, and sometimes combined, to bolster fragmentation and increase the number of identified fragments. Here, we present a design of experiments (DOE) approach to optimize MS2 parameters, in particular those that may influence electron transfer dissociation (ETD) efficiency to increase the sequence coverage of antibody subunits. Applying this approach to the NIST monoclonal antibody standard (NISTmAb) using three RPLC-MS2 runs resulted in high sequence coverages of 67%, 67%, and 52% for Fc/2, LC, and Fd subunits, respectively. In addition, we apply this DOE strategy to model the parameters required to maximize the number of fragments produced in "low", "medium", and "high" mass ranges, which ultimately resulted in even higher sequence coverages of NISTmAb subunits (75%, 78%, and 64% for Fc/2, LC, and Fd subunits, respectively). The DOE approach provides high sequence coverage percentages utilizing only one fragmentation method, ETD, and could be extended to other state-of-the-art techniques that combine multiple fragmentation mechanisms to increase coverage.
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Affiliation(s)
- Milos Cejkov
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Tyler Greer
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Reid O'Brien Johnson
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Xiaojing Zheng
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
| | - Ning Li
- Analytical Chemistry, Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, New York 10591-6707, United States
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15
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Fang M, Wang Z, Cupp-Sutton KA, Welborn T, Smith K, Wu S. High-throughput hydrogen deuterium exchange mass spectrometry (HDX-MS) coupled with subzero-temperature ultrahigh pressure liquid chromatography (UPLC) separation for complex sample analysis. Anal Chim Acta 2021; 1143:65-72. [PMID: 33384131 PMCID: PMC8265693 DOI: 10.1016/j.aca.2020.11.022] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 10/31/2020] [Accepted: 11/16/2020] [Indexed: 11/23/2022]
Abstract
Hydrogen deuterium exchange coupled with mass spectrometry (HDX-MS) is a powerful technique for the characterization of protein dynamics and protein interactions. Recent technological developments in the HDX-MS field, such as sub-zero LC separations, large-scale data analysis tools, and efficient protein digestion methods, have allowed for the application of HDX-MS to the analysis of multi protein systems in addition to pure protein analysis. Still, high-throughput HDX-MS analysis of complex samples is not widespread because the co-elution of peptides combined with increased peak complexity after labeling makes peak de-convolution extremely difficult. Here, for the first time, we evaluated and optimized long gradient subzero-temperature ultra-high-pressure liquid chromatography (UPLC) separation conditions for the HDX-MS analysis of complex protein samples such as E. coli cell lysate digest. Under the optimized conditions, we identified 1419 deuterated peptides from 320 proteins at -10 °C, which is about 3-fold more when compared with a 15-min gradient separation under the same conditions. Interestingly, our results suggested that the peptides eluted late in the gradient are well-protected by peptide-column interactions at -10 °C so that peptides eluted even at the end of the gradient maintain high levels of deuteration. Overall, our study suggests that the optimized, sub-zero, long-gradient UPLC separation is capable of characterizing thousands of peptides in a single HDX-MS analysis with low back-exchange rates. As a result, this technique holds great potential for characterizing complex samples such as cell lysates using HDX-MS.
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Affiliation(s)
- Mulin Fang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Thomas Welborn
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Kenneth Smith
- Department of Arthritis and Clinical Immunology, Oklahoma Medical Research Foundation, Oklahoma City, OK, 73104, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA.
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16
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Zeneyedpour L, Sten-van `t Hoff J, Luider T. Using phosphoproteomics and next generation sequencing to discover novel therapeutic targets in patient antibodies. Expert Rev Proteomics 2020; 17:675-684. [DOI: 10.1080/14789450.2020.1845147] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Lona Zeneyedpour
- Department of Neurology, Erasmus MC, Laboratory of Neuro-Oncology/Clinical & Cancer Proteomics, Rotterdam, The Netherlands
| | - Jenny Sten-van `t Hoff
- Department of Neurology, Erasmus MC, Laboratory of Neuro-Oncology/Clinical & Cancer Proteomics, Rotterdam, The Netherlands
| | - Theo Luider
- Department of Neurology, Erasmus MC, Laboratory of Neuro-Oncology/Clinical & Cancer Proteomics, Rotterdam, The Netherlands
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17
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Wang Z, Yu D, Cupp-Sutton KA, Liu X, Smith K, Wu S. Development of an Online 2D Ultrahigh-Pressure Nano-LC System for High-pH and Low-pH Reversed Phase Separation in Top-Down Proteomics. Anal Chem 2020; 92:12774-12777. [PMID: 32857493 PMCID: PMC7544661 DOI: 10.1021/acs.analchem.0c03395] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The development of novel high-resolution separation techniques is crucial for advancing the complex sample analysis necessary for high-throughput top-down proteomics. Recently, our group developed an offline 2D high-pH RPLC/low-pH RPLC separation method and demonstrated good orthogonality between these two RPLC formats. Specifically, ultrahigh-pressure long capillary column RPLC separation has been applied as the second dimensional low-pH RPLC separation for the improvement of separation resolution. To further improve the throughput and sensitivity of the offline approach, we developed an online 2D ultrahigh-pressure nano-LC system for high-pH and low-pH RPLC separations in top-down proteomics. An online microtrap column with a dilution setup was used to collect eluted proteins from the first dimension high-pH separation and inject the fractions for ultrahigh-pressure long capillary column low-pH RPLC separation in the second dimension. This automatic platform enables the characterization of 1000+ intact proteoforms from 5 μg of intact E. coli cell lysate in 10 online-collected fractions. Here, we have demonstrated that our online 2D pH RP/RPLC system coupled with top-down proteomics holds the potential for deep proteome characterization of mass-limited samples because it allows the identification of hundreds of intact proteoforms from complex biological samples at low microgram sample amounts.
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Affiliation(s)
- Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
| | - Xiaowen Liu
- School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, Indiana 46202, United States
| | - Kenneth Smith
- Arthritis & Clinical Immunology Research Program, Oklahoma Medical Research Foundation, 825 N.E. 13th Street, Oklahoma City, Oklahoma 73104, United States
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Norman, Oklahoma 73019, United States
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18
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Abstract
Top-down mass spectrometry (MS) analyzes intact proteins at the proteoform level, which allows researchers to better understand the functions of protein modifications. Recently, top-down proteomics has increased in popularity due to advancements in high-resolution mass spectrometers, increased efficiency in liquid chromatography (LC) separation, and advances in data analysis software. Some unique protein proteoforms, which have been distinguished using top-down MS, have even been shown to exhibit marked variation in biological function compared to similar proteoforms. However, the qualitative identification of a particular proteoform may not be enough to determine the biological relevance of that proteoform. Quantitative top-down MS methods have been notably applied to the study of the differing biological functions of protein proteoforms and have allowed researchers to explore proteomes at the proteoform, rather than the peptide, level. Here, we review the top-down MS methods that have been used to quantitatively identify intact proteins, discuss current applications of quantitative top-down MS analysis, and present new areas where quantitative top-down MS analysis may be implemented.
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Affiliation(s)
- Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK 73019-5251, USA.
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19
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Lee AYS, Chataway T, Colella AD, Gordon TP, Wang JJ. Quantitative Mass Spectrometric Analysis of Autoantibodies as a Paradigm Shift in Autoimmune Serology. Front Immunol 2019; 10:2845. [PMID: 31867009 PMCID: PMC6904311 DOI: 10.3389/fimmu.2019.02845] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Accepted: 11/19/2019] [Indexed: 12/11/2022] Open
Affiliation(s)
- Adrian Y S Lee
- Department of Immunology, SA Pathology, Flinders Medical Centre, Adelaide, SA, Australia.,College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Tim Chataway
- College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Alex D Colella
- Department of Immunology, SA Pathology, Flinders Medical Centre, Adelaide, SA, Australia.,College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Tom P Gordon
- Department of Immunology, SA Pathology, Flinders Medical Centre, Adelaide, SA, Australia.,College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
| | - Jing J Wang
- Department of Immunology, SA Pathology, Flinders Medical Centre, Adelaide, SA, Australia.,College of Medicine and Public Health, Flinders University, Adelaide, SA, Australia
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20
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Yu D, Wang Z, Cupp-Sutton KA, Liu X, Wu S. Deep Intact Proteoform Characterization in Human Cell Lysate Using High-pH and Low-pH Reversed-Phase Liquid Chromatography. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2019; 30:2502-2513. [PMID: 31755044 PMCID: PMC7539543 DOI: 10.1007/s13361-019-02315-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2019] [Revised: 08/10/2019] [Accepted: 08/10/2019] [Indexed: 05/26/2023]
Abstract
Post-translational modifications (PTMs) play critical roles in biological processes and have significant effects on the structures and dynamics of proteins. Top-down proteomics methods were developed for and applied to the study of intact proteins and their PTMs in human samples. However, the large dynamic range and complexity of human samples makes the study of human proteins challenging. To address these challenges, we developed a 2D pH RP/RPLC-MS/MS technique that fuses high-resolution separation and intact protein characterization to study the human proteins in HeLa cell lysate. Our results provide a deep coverage of soluble proteins in human cancer cells. Compared to 225 proteoforms from 124 proteins identified when 1D separation was used, 2778 proteoforms from 628 proteins were detected and characterized using our 2D separation method. Many proteoforms with critically functional PTMs including phosphorylation were characterized. Additionally, we present the first detection of intact human GcvH proteoforms with rare modifications such as octanoylation and lipoylation. Overall, the increase in the number of proteoforms identified using 2DLC separation is largely due to the reduction in sample complexity through improved separation resolution, which enables the detection of low-abundance PTM-modified proteoforms. We demonstrate here that 2D pH RP/RPLC is an effective technique to analyze complex protein samples using top-down proteomics.
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Affiliation(s)
- Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK, 73019-5251, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK, 73019-5251, USA
| | - Kellye A Cupp-Sutton
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK, 73019-5251, USA
| | - Xiaowen Liu
- School of Informatics and Computing, Indiana University-Purdue University Indianapolis, Indianapolis, IN, 46202, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, 101 Stephenson Parkway, Room 2210, Norman, OK, 73019-5251, USA.
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21
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Huguet R, Mullen C, Srzentić K, Greer JB, Fellers RT, Zabrouskov V, Syka JEP, Kelleher NL, Fornelli L. Proton Transfer Charge Reduction Enables High-Throughput Top-Down Analysis of Large Proteoforms. Anal Chem 2019; 91:15732-15739. [PMID: 31714757 DOI: 10.1021/acs.analchem.9b03925] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Despite the recent technological advances in Fourier transform mass spectrometry (FTMS) instrumentation, top-down proteomics (TDP) is currently mostly applied to the characterization of proteoforms <30 kDa due to the poor performance of high-resolution FTMS for the analysis of larger proteoforms and the high complexity of intact proteomes in the 30-60 kDa mass range. Here, we propose a novel data acquisition method based on ion-ion proton transfer, herein termed proton transfer charge reduction (PTCR), to investigate large proteoforms of Pseudomonas aeruginosa in a high-throughput fashion. We designed a targeted data acquisition strategy, named tPTCR, which applies two consecutive gas phase fractionation steps for obtaining intact precursor masses: first, a narrow (1.5 m/z-wide) quadrupole filter m/z transmission window is used to select a subset of charge states from all ionized proteoform cations; second, this aliquot of protein cations is subjected to PTCR in order to reduce their average charge state: upon m/z analysis in an Orbitrap, proteoform mass spectra with minimal m/z peak overlap and easy-to-interpret charge state distributions are obtained, simplifying the proteoform mass calculation. Subsequently, the same quadrupole-selected narrow m/z region of analytes is subjected to collisional dissociation to obtain proteoform sequence information, which used in combination with intact mass information leads to proteoform identification through an off-line database search. The newly proposed method was benchmarked against the previously developed "medium/high" data-dependent acquisition strategy and doubled the number of UniProt entries and proteoforms >30 kDa identified on the liquid chromatography time scale.
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Affiliation(s)
- Romain Huguet
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Christopher Mullen
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Kristina Srzentić
- Thermo Fisher Scientific , 790 Memorial Drive, Suite 2D , Cambridge , Massachusetts 02139 , United States
| | - Joseph B Greer
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence , Northwestern University , 2170 Campus Drive , Evanston , Illinois 60208 , United States
| | - Ryan T Fellers
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence , Northwestern University , 2170 Campus Drive , Evanston , Illinois 60208 , United States
| | - Vlad Zabrouskov
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - John E P Syka
- Thermo Fisher Scientific , 355 River Oaks Parkway , San Jose , California 95134 , United States
| | - Neil L Kelleher
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence , Northwestern University , 2170 Campus Drive , Evanston , Illinois 60208 , United States
| | - Luca Fornelli
- Department of Biology , University of Oklahoma , 730 Van Vleet Oval , Norman , Oklahoma 73071 , United States
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22
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Schaffer LV, Millikin RJ, Miller RM, Anderson LC, Fellers RT, Ge Y, Kelleher NL, LeDuc RD, Liu X, Payne SH, Sun L, Thomas PM, Tucholski T, Wang Z, Wu S, Wu Z, Yu D, Shortreed MR, Smith LM. Identification and Quantification of Proteoforms by Mass Spectrometry. Proteomics 2019; 19:e1800361. [PMID: 31050378 PMCID: PMC6602557 DOI: 10.1002/pmic.201800361] [Citation(s) in RCA: 128] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2019] [Revised: 04/07/2019] [Indexed: 12/29/2022]
Abstract
A proteoform is a defined form of a protein derived from a given gene with a specific amino acid sequence and localized post-translational modifications. In top-down proteomic analyses, proteoforms are identified and quantified through mass spectrometric analysis of intact proteins. Recent technological developments have enabled comprehensive proteoform analyses in complex samples, and an increasing number of laboratories are adopting top-down proteomic workflows. In this review, some recent advances are outlined and current challenges and future directions for the field are discussed.
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Affiliation(s)
- Leah V Schaffer
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Robert J Millikin
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Rachel M Miller
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Lissa C Anderson
- Ion Cyclotron Resonance Program, National High Magnetic Field Laboratory, Tallahassee, FL, 32310, USA
| | - Ryan T Fellers
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Ying Ge
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
- Department of Cell and Regenerative Biology and Human Proteomics Program, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Neil L Kelleher
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
- Department of Chemistry and Molecular Biosciences and the Division of Hematology and Oncology, Northwestern University, Evanston, IL, 60208, USA
| | - Richard D LeDuc
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Xiaowen Liu
- Department of BioHealth Informatics, Indiana University-Purdue University, Indianapolis, IN, 46202, USA
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, 46202, USA
| | - Samuel H Payne
- Department of Biology, Brigham Young University, Provo, UT, 84602
| | - Liangliang Sun
- Department of Chemistry, Michigan State University, East Lansing, MI, 48824, USA
| | - Paul M Thomas
- Proteomics Center of Excellence, Northwestern University, Evanston, IL, 60208, USA
| | - Trisha Tucholski
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Zhe Wang
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Si Wu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Zhijie Wu
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Dahang Yu
- Department of Chemistry and Biochemistry, University of Oklahoma, Norman, OK, 73019, USA
| | - Michael R Shortreed
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
| | - Lloyd M Smith
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, 53706, USA
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