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Thymosin α-1 in cancer therapy: Immunoregulation and potential applications. Int Immunopharmacol 2023; 117:109744. [PMID: 36812669 DOI: 10.1016/j.intimp.2023.109744] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2022] [Revised: 01/11/2023] [Accepted: 01/12/2023] [Indexed: 02/22/2023]
Abstract
Thymosin α-1 (Tα-1) is an immunomodulating polypeptide of 28 amino acids, which was the first peptide isolated from thymic tissue and has been widely used for the treatment of viral infections, immunodeficiencies, and especially malignancies. Tα-1 stimulates both innate and adaptive immune responses, and its regulation of innate immune cells and adaptive immune cells varies under different disease conditions. Pleiotropic regulation of immune cells by Tα-1 depends on activation of Toll-like receptors and its downstream signaling pathways in various immune microenvironments. For treatment of malignancies, the combination of Tα-1 and chemotherapy has a strong synergistic effect by enhancing the anti-tumor immune response. On the basis of the pleiotropic effect of Tα-1 on immune cells and the promising results of preclinical studies, Tα-1 may be a favorable immunomodulator to enhance the curative effect and decrease immune-related adverse events of immune checkpoint inhibitors to develop novel cancer therapies.
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The potential for isotope dilution-LC-MS/MS to improve laboratory measurement of C-peptide: Reasons and critical determinants. J Mass Spectrom Adv Clin Lab 2021; 21:1-9. [PMID: 34820671 PMCID: PMC8600993 DOI: 10.1016/j.jmsacl.2021.07.001] [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: 03/05/2021] [Revised: 07/28/2021] [Accepted: 07/29/2021] [Indexed: 11/21/2022] Open
Abstract
Human C-peptide is secreted in equimolar amounts with insulin by pancreatic beta-cells. Measurement of C-peptide plays an important role in the diagnosis and treatment of diabetes where it is used to evaluate the function of islet cells. However, C-peptide measurement results across different laboratories vary considerably and there is an urgent need to improve comparability between laboratories. As it is sensitive and specific, isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS) has made a major contribution and will continue to play a significant role in the standardization of C-peptide measurement. Here, we reviewed the application of ID-LC-MS/MS in C-peptide measurement by discussing the biochemical properties of C-peptide, common sample preparation procedures, and the sensitivity problems often encountered with ID-LC-MS/MS C-peptide measurement. Collectively, these factors are crucial for the development of ID-LC-MS/MS methods for C-peptide measurement. We also discussed the advantages, disadvantages, and progress of implementing ID-LC-MS/MS as a routine measurement tool for C-peptide in clinical laboratories. Finally, we summarized the existing reference system and the status of C-peptide measurement in clinical laboratories to convey the necessity of improving the comparability of C-peptide measurement in clinical laboratories using ID-LC-MS/MS.
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Dominari A, III DH, Pandav K, Matos W, Biswas S, Reddy G, Thevuthasan S, Khan MA, Mathew A, Makkar SS, Zaidi M, Fahem MMM, Beas R, Castaneda V, Paul T, Halpern J, Baralt D. Thymosin alpha 1: A comprehensive review of the literature. World J Virol 2020; 9:67-78. [PMID: 33362999 PMCID: PMC7747025 DOI: 10.5501/wjv.v9.i5.67] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 11/19/2020] [Accepted: 12/02/2020] [Indexed: 02/06/2023] Open
Abstract
Thymosin alpha 1 is a peptide naturally occurring in the thymus that has long been recognized for modifying, enhancing, and restoring immune function. Thymosin alpha 1 has been utilized in the treatment of immunocompromised states and malignancies, as an enhancer of vaccine response, and as a means of curbing morbidity and mortality in sepsis and numerous infections. Studies have postulated that thymosin alpha 1 could help improve the outcome in severely ill corona virus disease 2019 patients by repairing damage caused by overactivation of lymphocytic immunity and how thymosin alpha 1 could prevent the excessive activation of T cells. In this review, we discuss key literature on the background knowledge and current clinical uses of thymosin alpha 1. Considering the known biochemical properties including antibacterial and antiviral properties, time-honored applications, and the new promising findings regarding the use of thymosin, we believe that thymosin alpha 1 deserves further investigation into its antiviral properties and possible repurposing as a treatment against severe acute respiratory syndrome coronavirus-2.
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Affiliation(s)
- Asimina Dominari
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Donald Hathaway III
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Krunal Pandav
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Wanessa Matos
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Sharmi Biswas
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Gowry Reddy
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Sindhu Thevuthasan
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Muhammad Adnan Khan
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Anoopa Mathew
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Sarabjot Singh Makkar
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Madiha Zaidi
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | | | - Renato Beas
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Valeria Castaneda
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Trissa Paul
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - John Halpern
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
| | - Diana Baralt
- Division of Research and Academic Affairs, Larkin Health System, South Miami, FL 33143, United States
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Wang T, Yin L, Wang H, Fawcett JP, Gu J. Development and application of a high-throughput liquid chromatography-tandem mass spectrometric method for the simultaneous determination of thymosin α1 and its recombinant human form in plasma and urine. J Pharm Biomed Anal 2019; 170:16-21. [PMID: 30903925 DOI: 10.1016/j.jpba.2019.03.030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/08/2019] [Accepted: 03/14/2019] [Indexed: 10/27/2022]
Abstract
Thymosin α1 (Thymalfasin, Tα1) is a naturally occurring polypeptide widely used as an immune system enhancer for the treatment of HIV/AIDS, hepatitis B and C, and cancer. Recombinant human Tα1 (rh-Tα1) lacking N-terminal acetylation (NTA) displays similar biological activity to Tα1 and has completed phase III clinical trials in China. To compare the pharmacokinetics of rh-Tα1 and Tα1 and establish whether they undergo mutual transmutation in vivo, we developed a novel bioassay based on liquid chromatography-tandem mass spectrometry (LC-MS/MS) for the simultaneous determination of the two peptides in human plasma and urine. Sample preparation by protein precipitation using a mixture of methanol and perchloric acid was followed by HPLC on a Zorbax 300SB-C18 column (150 × 4.6 mm, 5 μm) maintained at 40 °C. Detection was by multiple reaction monitoring (MRM) of the precursor-to-product ion transitions at m/z 778.0→316.0 for Tα1, m/z 767.3→955.0 for rh-Tα1 and m/z 832.3→159.2 for the internal standard, eptifibatide. The method was linear in the range 2-100 ng/mL for both analytes with good accuracy and precision. High sample throughput was facilitated by inclusion of a parallel two-column chromatographic system. The method was successfully applied to a comparative pharmacokinetic study involving single subcutaneous injections of either Tα1 or rh-Tα1 to two groups of healthy male volunteers. The results indicate that rh-Tα1 undergoes NTA in vivo to form Tα1 but that Tα1 is not deacetylated to rh-Tα1.
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Affiliation(s)
- Tingting Wang
- Research Institute of Translational Medicine, The First Bethune Hospital of Jilin University, Changchun, 130061, PR China; Research Center for Drug Metabolism, College of Life Science, Jilin University, Changchun, 130012, PR China
| | - Lei Yin
- Research Institute of Translational Medicine, The First Bethune Hospital of Jilin University, Changchun, 130061, PR China; Research Center for Drug Metabolism, College of Life Science, Jilin University, Changchun, 130012, PR China
| | - Hao Wang
- School of Life Sciences, Northeast Normal University, Changchun, 130024, PR China
| | - John Paul Fawcett
- Research Center for Drug Metabolism, College of Life Science, Jilin University, Changchun, 130012, PR China
| | - Jingkai Gu
- Research Institute of Translational Medicine, The First Bethune Hospital of Jilin University, Changchun, 130061, PR China; Research Center for Drug Metabolism, College of Life Science, Jilin University, Changchun, 130012, PR China; Beijing Institute of Drug Metabolism, Beijing, 102209, PR China.
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Pica F, Gaziano R, Casalinuovo IA, Moroni G, Buè C, Limongi D, D'Agostini C, Tomino C, Perricone R, Palamara AT, Sinibaldi Vallebona P, Garaci E. Serum thymosin alpha 1 levels in normal and pathological conditions. Expert Opin Biol Ther 2019; 18:13-21. [PMID: 30063864 DOI: 10.1080/14712598.2018.1474197] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
INTRODUCTION Thymosin alpha 1 (Ta1) is a natural occurring peptide hormone that is crucial for the maintenance of the organism homeostasis. It has been chemically synthesized and used in diseases where the immune system is hindered or malfunctioning. AREAS COVERED Many clinical trials investigate the Ta1 effects in patients with cancer, infectious diseases and as a vaccine enhancer. The number of diseases that could benefit from Ta1 treatment is increasing. To date, questions remain about the physiological basal levels of Ta1 and the most effective dose and schedule of treatment. Evidence is growing that diseases characterized by deregulation of immune and/or inflammatory responses are associated with serum levels of Ta1 significantly lower than those of healthy individuals: to date, B hepatitis, psoriatic arthritis, multiple sclerosis and sepsis. The sputum of cystic fibrosis patients contains lower levels of Ta1 than healthy controls. These data are consistent with the role of Ta1 as a regulator of immunity, tolerance and inflammation. EXPERT OPINION Low serum Ta1 levels are predictive and/or associated with different pathological conditions. In case of Ta1 treatment, it is crucial to know the patient's baseline serum Ta1 level to establish effective treatment protocols and monitor their effectiveness over time.
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Affiliation(s)
- Francesca Pica
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy
| | - Roberta Gaziano
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy
| | | | - Gabriella Moroni
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy
| | - Cristina Buè
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy
| | - Dolores Limongi
- b IRCCS San Raffaele Pisana , Telematic University , Rome , Italy
| | - Cartesio D'Agostini
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy
| | - Carlo Tomino
- b IRCCS San Raffaele Pisana , Telematic University , Rome , Italy
| | - Roberto Perricone
- c Medicine of Systems, Rheumatology, Allergology and Clinical Immunology , University Tor Vergata , Rome , Italy
| | - Anna Teresa Palamara
- b IRCCS San Raffaele Pisana , Telematic University , Rome , Italy.,d Department of Public Health and Infectious Diseases , Sapienza University of Rome , Rome , Italy
| | | | - Enrico Garaci
- a Departments of Experimental Medicine and Surgery , University Tor Vergata , Rome , Italy.,b IRCCS San Raffaele Pisana , Telematic University , Rome , Italy
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Abstract
Peptides and proteins have been utilized as therapeutic agents for over 40 years. Traditional approaches to quantify these molecules in biological matrices have utilized immunoassay approaches that can be time inefficient, lack assay specificity and have limited analytical ranges. The advances in sample preparation technologies, chromatographic systems and their chemistries, mass spectrometers and their software over the last decade have meant that LC–MS/MS approaches to peptide and protein quantification are feasible and can overcome the problems associated with quantification by immunoassay. In this article we present an overview of the challenges and approaches to overcome them when performing quantitative bioanalysis of peptides and proteins by LC–MS/MS.
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Quantitative analysis of skeletal symmetric chlorhexidine in rat plasma using doubly charged molecular ions in LC–MS/MS detection. Bioanalysis 2011; 3:1357-68. [DOI: 10.4155/bio.11.85] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Background: The skeletal symmetric structure of chlorhexidine predicts that each doubly charged molecular ion may generate two para-chlorbenzenguanidines daughter ions through bond cleavage at two protonation sites, thus generating better sensitivity in MRM transition than that involving singly charged molecular ions. This unique nature can be used to improve sensitivity of a LC–MS/MS method. Results: High-throughput LC–MS/MS was developed and validated to quantify chlorhexidine in rat plasma as low as 0.500 ng/ml. In the method, a unique chromatographic method on a narrow bore column reduced run time to 2.5 min and successfully minimized high background from accumulation of endogenous compounds in matrix on the column. Conclusion: This method was proved to be robust and suitable to support rat dermal toxicology studies.
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Evaluation of pharmacokinetics of bioreducible gene delivery vectors by real-time PCR. Pharm Res 2009; 26:1581-9. [PMID: 19240986 DOI: 10.1007/s11095-009-9847-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2008] [Accepted: 02/04/2009] [Indexed: 12/18/2022]
Abstract
PURPOSE To investigate pharmacokinetics of reversibly stabilized DNA nanoparticles (rSDN) using a single-step lysis RT-PCR. METHODS rSDN were prepared by coating bioreducible polycation/DNA polyplexes with multivalent N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers. Targeted polyplexes were formulated by linking cyclic RGD ligand (c(RGDyK)) to the HPMA surface layer of rSDN. The pharmacokinetic parameters in tumor-bearing mice were analyzed by PKAnalyst. RESULTS The pharmacokinetics of naked plasmid DNA, simple DNA polyplexes, rSDN, and RGD-targeted rSDN exhibited two-compartment model characteristics with area under the blood concentration-time curve (AUC) increasing from 1,102 ng x ml(-1) x min(-1) for DNA to 3,501 ng x ml(-1) x min(-1) for rSDN. Non-compartment model analysis revealed increase in mean retention time (MRT) from 4.5 min for naked DNA to 22.9 min for rSDN. CONCLUSIONS RT-PCR is a sensitive and convenient method suitable for analyzing pharmacokinetics and biodistribution of DNA polyplexes. Surface stabilization of DNA polyplexes can significantly extend their MRT and AUC compared to naked DNA. DNA degradation in rSDN in blood circulation, due to a combined effect of disulfide reduction and competitive reactions with charged molecules in the blood, contributes to DNA elimination.
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Anderson NL, Anderson NG, Pearson TW, Borchers CH, Paulovich AG, Patterson SD, Gillette M, Aebersold R, Carr SA. A human proteome detection and quantitation project. Mol Cell Proteomics 2009; 8:883-6. [PMID: 19131327 DOI: 10.1074/mcp.r800015-mcp200] [Citation(s) in RCA: 173] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The lack of sensitive, specific, multiplexable assays for most human proteins is the major technical barrier impeding development of candidate biomarkers into clinically useful tests. Recent progress in mass spectrometry-based assays for proteotypic peptides, particularly those with specific affinity peptide enrichment, offers a systematic and economical path to comprehensive quantitative coverage of the human proteome. A complete suite of assays, e.g. two peptides from the protein product of each of the approximately 20,500 human genes (here termed the human Proteome Detection and Quantitation project), would enable rapid and systematic verification of candidate biomarkers and lay a quantitative foundation for subsequent efforts to define the larger universe of splice variants, post-translational modifications, protein-protein interactions, and tissue localization.
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Gao D, Zhang X, Zhang J, Cao J, Wang F. Expression of thymosin alpha1-thymopentin fusion peptide in Pichia pastoris and its characterization. Arch Pharm Res 2008; 31:1471-6. [PMID: 19023544 DOI: 10.1007/s12272-001-2132-z] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2008] [Revised: 10/25/2008] [Accepted: 10/27/2008] [Indexed: 11/26/2022]
Abstract
Thymopentin plays an important role in improving imbalanced immune systems of patients, however, it has a limited half-life in plasma. To get more stable and active thymopentin analogs, a fusion thymosin alpha1-thymopentin (Talpha1-TP5) gene was synthesized and cloned into vector pGAPZalphaA. Talpha1-TP5 fusion peptide was expressed in pichia pastoris and purified by metal chelating chromatography and gel filtration chromatography. The circular dichroism spectra (CD) indicated that the secondary structure of Talpha1-TP5 fusion peptide is dominated by a-helix and random coil. In vitro analysis showed that the plasma half-life of Talpha1-TP5 fusion peptide is 140 +/- 14 min, which is longer than that of TP5 (5.6+/-0.7 min) and Talpha1 (127+/-11 min). The in vitro activity assay presented that Talpha1-TP5 fusion peptide has greater activity in promoting proliferation of Kunming mouse splenocytes, and in vivo experiment it showed better activity in promoting the phagocytosis of macrophages and secretion of IL-2 than both Talpha1 and TP5. Our findings suggest that Talpha1-TP5 fusion peptide might be a potential therapeutic agent.
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Affiliation(s)
- Demin Gao
- Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China
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van den Broek I, Sparidans RW, Schellens JH, Beijnen JH. Quantitative bioanalysis of peptides by liquid chromatography coupled to (tandem) mass spectrometry. J Chromatogr B Analyt Technol Biomed Life Sci 2008; 872:1-22. [DOI: 10.1016/j.jchromb.2008.07.021] [Citation(s) in RCA: 134] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 06/16/2008] [Accepted: 07/12/2008] [Indexed: 12/25/2022]
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PUMFERY ANNE, BERRO REEM, KASHANCHI FATAH. Proteomics of viruses. MEDICAL APPLICATIONS OF MASS SPECTROMETRY 2008. [PMCID: PMC7151880 DOI: 10.1016/b978-044451980-1.50017-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Proteomics is a promising approach for the study of viruses allowing a better understanding of disease processes and the development of new biomarkers for diagnosis and early detection of disease, thus accelerating drug development. Viral proteomics has included the analysis of viral particles to determine all proteins that compose the infectious virus, the examination of cellular proteins associated with a single viral protein in the hopes of determining all the functions of that viral protein, or the determination of cellular proteins induced or altered during a particular disease state. Viral particles of human cytomegalovirus (HCMV) and Kaposi's sarcoma-associated herpesvirus/human herpesvirus 8 (KSHV/HHV-8) have been recently examined. During the herpesviral replicative cycle, different viral particles are formed. For HCMV, this includes mature, infectious virions, noninfectious enveloped particles, and dense bodies. A proteome database of B-lymphoblastoid cell lines (LCLs), before and after transformation, has been developed to identify the cellular mechanisms of virus-induced immortalization. 2DE is used to first separate proteins based on their relative charge (pI) and then based on their molecular weight. Proteomic analysis has provided a unique tool for the identification of diagnostic biomarkers, evaluation of disease progression, and drug development. It is also an important approach for clinical diagnostics.
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Affiliation(s)
- ANNE PUMFERY
- Department of Biochemistry and Molecular Biology, The George Washington University, Washington, DC 20037, USA
| | - REEM BERRO
- Department of Biochemistry and Molecular Biology, The George Washington University, Washington, DC 20037, USA
| | - FATAH KASHANCHI
- Department of Biochemistry and Molecular Biology, The George Washington University, Washington, DC 20037, USA
- The Institute for Genomic Research, Rockville, MD 20850, USA
- Corresponding author. Address: Department of Biochemistry and Molecular Biology, The George Washington University, Washington, DC 20037, USA. Tel.: 202-994-1782; Fax: +1-202-994-1780
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van den Broek I, Sparidans RW, Schellens JHM, Beijnen JH. Enzymatic digestion as a tool for the LC–MS/MS quantification of large peptides in biological matrices: Measurement of chymotryptic fragments from the HIV-1 fusion inhibitor enfuvirtide and its metabolite M-20 in human plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2007; 854:245-59. [PMID: 17500050 DOI: 10.1016/j.jchromb.2007.04.026] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2007] [Revised: 04/17/2007] [Accepted: 04/22/2007] [Indexed: 11/23/2022]
Abstract
The use of enzymatic digests of the peptide HIV-1 fusion inhibitor enfuvirtide as a tool for the absolute quantification of this polypeptide (MW 4492 Da) in human plasma by LC-MS/MS has been evaluated. Two different methods applying digestion of enfuvirtide with chymotrypsin after solid phase extraction (SPE) of the plasma samples have therefore been developed and validated. One method used a stable isotopically labeled analog of the complete peptide (d60-enfuvirtide) as internal standard (IS) and could use as much as four different chymotryptic fragments for the quantification of enfuvirtide in a range of 100-10,000 ng/ml. Intra- and inter-assay precisions and deviations from the nominal concentrations varied for the different fragments, but were below 9% when the four results were averaged. The other method used a stable isotopically labeled chymotryptic fragment of the peptide (d10-ASLW) as IS. Although this IS does not correct for variations in digestion recovery, it allows the selective quantification of enfuvirtide (100-10,000 ng/ml), besides the quantification of the sum of enfuvirtide and its de-amidated metabolite M-20 (120-12,000 ng/ml). Both methods were suitable for the absolute quantification of enfuvirtide and M-20 in plasma, but proper selection of the fragment(s) used for the quantification appeared crucial when the deuterated fragment was used as IS.
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Affiliation(s)
- Irene van den Broek
- Department of Pharmaceutical Sciences, Section of Biomedical Analysis, Division of Drug Toxicology, Utrecht University, Sorbonnelaan 16, 3584 CA Utrecht, The Netherlands.
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Anderson L. Candidate-based proteomics in the search for biomarkers of cardiovascular disease. J Physiol 2005; 563:23-60. [PMID: 15611012 PMCID: PMC1665562 DOI: 10.1113/jphysiol.2004.080473] [Citation(s) in RCA: 266] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2004] [Accepted: 12/16/2004] [Indexed: 11/08/2022] Open
Abstract
The key concept of proteomics (looking at many proteins at once) opens new avenues in the search for clinically useful biomarkers of disease, treatment response and ageing. As the number of proteins that can be detected in plasma or serum (the primary clinical diagnostic samples) increases towards 1000, a paradoxical decline has occurred in the number of new protein markers approved for diagnostic use in clinical laboratories. This review explores the limitations of current proteomics protein discovery platforms, and proposes an alternative approach, applicable to a range of biological/physiological problems, in which quantitative mass spectrometric methods developed for analytical chemistry are employed to measure limited sets of candidate markers in large sets of clinical samples. A set of 177 candidate biomarker proteins with reported associations to cardiovascular disease and stroke are presented as a starting point for such a 'directed proteomics' approach.
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