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Zhang Z, Hug C, Tao Y, Bitsch F, Yang Y. Solving Complex Biologics Truncation Problems by Top-Down Mass Spectrometry. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2021; 32:1928-1935. [PMID: 33395284 DOI: 10.1021/jasms.0c00343] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
With increasing protein therapeutics being designed as non-mAb (non-monoclonal antibody) modalities, additional efforts and resources are required to develop and characterize such therapeutic proteins. Truncation is an emerging issue for manufacturing of non-mAb drug substances and requires sophisticated methods to investigate. In this paper, we describe two cases with complex truncation problems where traditional methods such as intact mass spectrometry led to inclusive or wrong identifications. Therefore, we developed an online top-down LC-MS (liquid chromatography-mass spectrometry) based workflow to study truncated drug substances, and we successfully identified the clipping locations. Compared to other orthogonal methods, this method provides a unique capability of solving protein clipping problems. The successful identification of truncated species and the high compatibility to routine intact MS make it a very valuable tool for resolving truncation problems during protein production in the pharmaceutical industry.
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Affiliation(s)
- Zhe Zhang
- NIBR Biologics Center, Novartis Institutes for BioMedical Research, 100 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Christian Hug
- NIBR Biologics Center, Novartis Institutes for BioMedical Research, Klybeckstrasse 141, CH-4057, Basel, Switzerland
| | - Yuanqi Tao
- NIBR Biologics Center, Novartis Institutes for BioMedical Research, 100 Technology Square, Cambridge, Massachusetts 02139, United States
| | - Francis Bitsch
- NIBR Biologics Center, Novartis Institutes for BioMedical Research, Klybeckstrasse 141, CH-4057, Basel, Switzerland
| | - Yang Yang
- NIBR Biologics Center, Novartis Institutes for BioMedical Research, Klybeckstrasse 141, CH-4057, Basel, Switzerland
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Modernizing the Toolkit for Arthropod Bloodmeal Identification. INSECTS 2021; 12:insects12010037. [PMID: 33418885 PMCID: PMC7825046 DOI: 10.3390/insects12010037] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 12/30/2020] [Accepted: 12/31/2020] [Indexed: 11/24/2022]
Abstract
Simple Summary The ability to identify the source of vertebrate blood in mosquitoes, ticks, and other blood-feeding arthropod vectors greatly enhances our knowledge of how vector-borne pathogens are spread. The source of the bloodmeal is identified by analyzing the remnants of blood remaining in the arthropod at the time of capture, though this is often fraught with challenges. This review provides a roadmap and guide for those considering modern techniques for arthropod bloodmeal identification with a focus on progress made in the field over the past decade. We highlight genome regions that can be used to identify the vertebrate source of arthropod bloodmeals as well as technological advances made in other fields that have introduced innovative new ways to identify vertebrate meal source based on unique properties of the DNA sequence, protein signatures, or residual molecules present in the blood. Additionally, engineering progress in miniaturization has led to a number of field-deployable technologies that bring the laboratory directly to the arthropods at the site of collection. Although many of these advancements have helped to address the technical challenges of the past, the challenge of successfully analyzing degraded DNA in bloodmeals remains to be solved. Abstract Understanding vertebrate–vector interactions is vitally important for understanding the transmission dynamics of arthropod-vectored pathogens and depends on the ability to accurately identify the vertebrate source of blood-engorged arthropods in field collections using molecular methods. A decade ago, molecular techniques being applied to arthropod blood meal identification were thoroughly reviewed, but there have been significant advancements in the techniques and technologies available since that time. This review highlights the available diagnostic markers in mitochondrial and nuclear DNA and discusses their benefits and shortcomings for use in molecular identification assays. Advances in real-time PCR, high resolution melting analysis, digital PCR, next generation sequencing, microsphere assays, mass spectrometry, and stable isotope analysis each offer novel approaches and advantages to bloodmeal analysis that have gained traction in the field. New, field-forward technologies and platforms have also come into use that offer promising solutions for point-of-care and remote field deployment for rapid bloodmeal source identification. Some of the lessons learned over the last decade, particularly in the fields of DNA barcoding and sequence analysis, are discussed. Though many advancements have been made, technical challenges remain concerning the prevention of sample degradation both by the arthropod before the sample has been obtained and during storage. This review provides a roadmap and guide for those considering modern techniques for arthropod bloodmeal identification and reviews how advances in molecular technology over the past decade have been applied in this unique biomedical context.
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Hlavackova K, Dvorak V, Chaskopoulou A, Volf P, Halada P. A novel MALDI-TOF MS-based method for blood meal identification in insect vectors: A proof of concept study on phlebotomine sand flies. PLoS Negl Trop Dis 2019; 13:e0007669. [PMID: 31498786 PMCID: PMC6733444 DOI: 10.1371/journal.pntd.0007669] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 07/29/2019] [Indexed: 12/24/2022] Open
Abstract
Background Identification of blood sources of hematophagous arthropods is crucial for understanding the transmission cycles of vector-borne diseases. Many different approaches towards host determination were proposed, including precipitin test, ELISA, DNA- and mass spectrometry-based methods; yet all face certain complications and limitations, mostly related to blood degradation. This study presents a novel method for blood meal identification, peptide mass mapping (PMM) analysis of host-specific hemoglobin peptides using MALDI-TOF mass spectrometry. Methodology/Principal findings To identify blood meal source, proteins from abdomens of engorged sand fly females were extracted, cleaved by trypsin and peptide fragments of host hemoglobin were sequenced using MALDI-TOF MS. The method provided correct host identification of 100% experimentally fed sand flies until 36h post blood meal (PBM) and for 80% samples even 48h PBM. In females fed on two hosts, both blood meal sources were correctly assigned for 60% of specimens until 36h PBM. In a validation study on field-collected females, the method yielded unambiguous host determination for 96% of specimens. The suitability of PMM-based MALDI-TOF MS was proven experimentally also on lab-reared Culex mosquitoes. Conclusions/Significance PMM-based MALDI-TOF MS analysis targeting host specific hemoglobin peptides represents a sensitive and cost-effective method with a fast and simple preparation protocol. As demonstrated here on phlebotomine sand flies and mosquitoes, it allows reliable and rapid blood source determination even 48h PBM with minimal material input and provides more robust and specific results than other currently used methods. This approach was also successfully tested on field-caught engorged females and proved to be a promising useful tool for large-scale screening of host preferences studies. Unlike other methods including MALDI-TOF protein profiling, it allows correct identification of mixed blood meals as was demonstrated on both experimentally fed and field-collected sand flies. Leishmaniases belong among the most important and yet neglected vector-borne diseases, transmitted mostly by bite of female phlebotomine sand flies. To understand role of different reservoir hosts in the transmission cycles, it is important to determine blood meal sources of bloodfeeding females. Most of currently used methods face challenges due to tiny volumes of engorged blood, in case of mammals also enucleated, as well as quick progress of blood digestion which leads to rapid DNA and protein degradation. New approach towards blood source determination presented in this study is based on MALDI-TOF mass spectrometry that identifies unique peptide sequences of host hemoglobins, showing high precision and sensitivity together with a longer time period for successful host determination when compared to nowadays standardly used DNA sequencing. It was tested and verified on engorged phlebotomine sand flies from both laboratory colonies and natural endemic areas and also on Culex mosquitoes and shall be universal to hematophagous insects. Beside blood meal identification, it allows also the use of both morphological and molecular methods (DNA- or protein-based) for the species identification of the analysed specimen.
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Affiliation(s)
- Kristyna Hlavackova
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Vit Dvorak
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | | | - Petr Volf
- Department of Parasitology, Faculty of Science, Charles University, Prague, Czech Republic
| | - Petr Halada
- Institute of Microbiology of the Czech Academy of Sciences, Prague, Czech Republic
- * E-mail:
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Lyon YA, Riggs D, Fornelli L, Compton PD, Julian RR. The Ups and Downs of Repeated Cleavage and Internal Fragment Production in Top-Down Proteomics. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2018; 29:150-157. [PMID: 29038993 PMCID: PMC5786485 DOI: 10.1007/s13361-017-1823-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 09/08/2017] [Accepted: 09/23/2017] [Indexed: 05/10/2023]
Abstract
Analysis of whole proteins by mass spectrometry, or top-down proteomics, has several advantages over methods relying on proteolysis. For example, proteoforms can be unambiguously identified and examined. However, from a gas-phase ion-chemistry perspective, proteins are enormous molecules that present novel challenges relative to peptide analysis. Herein, the statistics of cleaving the peptide backbone multiple times are examined to evaluate the inherent propensity for generating internal versus terminal ions. The raw statistics reveal an inherent bias favoring production of terminal ions, which holds true regardless of protein size. Importantly, even if the full suite of internal ions is generated by statistical dissociation, terminal ions are predicted to account for at least 50% of the total ion current, regardless of protein size, if there are three backbone dissociations or fewer. Top-down analysis should therefore be a viable approach for examining proteins of significant size. Comparison of the purely statistical analysis with actual top-down data derived from ultraviolet photodissociation (UVPD) and higher-energy collisional dissociation (HCD) reveals that terminal ions account for much of the total ion current in both experiments. Terminal ion production is more favored in UVPD relative to HCD, which is likely due to differences in the mechanisms controlling fragmentation. Importantly, internal ions are not found to dominate from either the theoretical or experimental point of view. Graphical abstract ᅟ.
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Affiliation(s)
- Yana A Lyon
- Department of Chemistry, University of California, Riverside, 501 Big Springs Road, Riverside, CA, 92521, USA
| | - Dylan Riggs
- Department of Chemistry, University of California, Riverside, 501 Big Springs Road, Riverside, CA, 92521, USA
| | - Luca Fornelli
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, 2145 N. Sheridan Road, Evanston, IL, 60208, USA
| | - Philip D Compton
- Departments of Chemistry and Molecular Biosciences, and the Proteomics Center of Excellence, Northwestern University, 2145 N. Sheridan Road, Evanston, IL, 60208, USA
| | - Ryan R Julian
- Department of Chemistry, University of California, Riverside, 501 Big Springs Road, Riverside, CA, 92521, USA.
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Keller JI, Ballif BA, St. Clair RM, Vincent JJ, Monroy MC, Stevens L. Chagas disease vector blood meal sources identified by protein mass spectrometry. PLoS One 2017; 12:e0189647. [PMID: 29232402 PMCID: PMC5726658 DOI: 10.1371/journal.pone.0189647] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Accepted: 11/29/2017] [Indexed: 02/08/2023] Open
Abstract
Chagas disease is a complex vector borne parasitic disease involving blood feeding Triatominae (Hemiptera: Reduviidae) insects, also known as kissing bugs, and the vertebrates they feed on. This disease has tremendous impacts on millions of people and is a global health problem. The etiological agent of Chagas disease, Trypanosoma cruzi (Kinetoplastea: Trypanosomatida: Trypanosomatidae), is deposited on the mammalian host in the insect’s feces during a blood meal, and enters the host’s blood stream through mucous membranes or a break in the skin. Identifying the blood meal sources of triatomine vectors is critical in understanding Chagas disease transmission dynamics, can lead to identification of other vertebrates important in the transmission cycle, and aids management decisions. The latter is particularly important as there is little in the way of effective therapeutics for Chagas disease. Several techniques, mostly DNA-based, are available for blood meal identification. However, further methods are needed, particularly when sample conditions lead to low-quality DNA or to assess the risk of human cross-contamination. We demonstrate a proteomics-based approach, using liquid chromatography tandem mass spectrometry (LC-MS/MS) to identify host-specific hemoglobin peptides for blood meal identification in mouse blood control samples and apply LC-MS/MS for the first time to Triatoma dimidiata insect vectors, tracing blood sources to species. In contrast to most proteins, hemoglobin, stabilized by iron, is incredibly stable even being preserved through geologic time. We compared blood stored with and without an anticoagulant and examined field-collected insect specimens stored in suboptimal conditions such as at room temperature for long periods of time. To our knowledge, this is the first study using LC-MS/MS on field-collected arthropod disease vectors to identify blood meal composition, and where blood meal identification was confirmed with more traditional DNA-based methods. We also demonstrate the potential of synthetic peptide standards to estimate relative amounts of hemoglobin acquired when insects feed on multiple blood sources. These LC-MS/MS methods can contribute to developing Ecohealth control strategies for Chagas disease transmission and can be applied to other arthropod disease vectors.
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Affiliation(s)
- Judith I. Keller
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - Bryan A. Ballif
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- * E-mail: (LS); (BAB)
| | - Riley M. St. Clair
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - James J. Vincent
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
| | - M. Carlota Monroy
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- Laboratorio de Entomología Aplicada y Parasitología, Escuela de Biología, Facultad de Ciencias Químicas y Farmacia, Universidad de San Carlos de Guatemala, Ciudad de Guatemala, Guatemala
| | - Lori Stevens
- Department of Biology, University of Vermont, Burlington, Vermont, United States of America
- * E-mail: (LS); (BAB)
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