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Kullmann D, Lema Martinez C, Lümkemann J, Huwyler J. Part II: Matrix based scaffold lyophilization facilitates processing as a prerequisite for an innovative packaging system. Eur J Pharm Biopharm 2023; 184:262-273. [PMID: 36565968 DOI: 10.1016/j.ejpb.2022.12.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 12/24/2022]
Abstract
On large manufacturing lines, the fill finish process of drugs is generally accomplished by filling vials and syringes with their respective deliverable doses. Glass as a final container provides excellent protection of the drug product because of its chemical inertia, gas impermeability and relative robustness. However, due to potential needle stitch issues, diluent mix ups, or the required use of complex closed system transfer devices, lyophilizate vials present a significant challenge for healthcare professionals during the correct preparation of intravenous (IV) infusions. A more suitable container could potentially minimize such shortfalls during the preparation of IV infusions. Our investigations aimed at assessing if a novel medication system, consisting of an infusion bag separated into individual dry product and liquid diluent chambers, could facilitate the storage of a lyophilized product equivalently to the current standard, a vial. By incorporating an intermediate process container into two different dual chamber bags (DCB), the stability of a model monoclonal antibody formulation (mAb) was studied. The DCBs were evaluated over a 24-week period against their liquid and lyophilized dosage form equivalents in glass vials. Their stability was assessed through investigations into protein stability, residual moisture uptake of the dry products and permeability of the foil and film materials. It could be demonstrated that the stability of the incorporated drug is highly dependent on the container configuration. Ultimately it could be shown that the storage of lyophilizates is equally possible in DCBs as it is in vials, while being stored next to the diluent within the administration device.
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Affiliation(s)
- Daniel Kullmann
- F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland; Division of Pharmaceutical Technology, Department of Pharmaceutical Sciences, University of Basel, 4056 Basel, Switzerland.
| | | | - Jörg Lümkemann
- F. Hoffmann-La Roche Ltd, Grenzacherstrasse 124, 4070 Basel, Switzerland
| | - Jörg Huwyler
- Division of Pharmaceutical Technology, Department of Pharmaceutical Sciences, University of Basel, 4056 Basel, Switzerland
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2
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Potential Therapies Targeting the Metabolic Reprogramming of Diabetes-Associated Breast Cancer. J Pers Med 2023; 13:jpm13010157. [PMID: 36675817 PMCID: PMC9861470 DOI: 10.3390/jpm13010157] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2022] [Revised: 01/08/2023] [Accepted: 01/10/2023] [Indexed: 01/18/2023] Open
Abstract
In recent years, diabetes-associated breast cancer has become a significant clinical challenge. Diabetes is not only a risk factor for breast cancer but also worsens its prognosis. Patients with diabetes usually show hyperglycemia and hyperinsulinemia, which are accompanied by different glucose, protein, and lipid metabolism disorders. Metabolic abnormalities observed in diabetes can induce the occurrence and development of breast cancer. The changes in substrate availability and hormone environment not only create a favorable metabolic environment for tumorigenesis but also induce metabolic reprogramming events required for breast cancer cell transformation. Metabolic reprogramming is the basis for the development, swift proliferation, and survival of cancer cells. Metabolism must also be reprogrammed to support the energy requirements of the biosynthetic processes in cancer cells. In addition, metabolic reprogramming is essential to enable cancer cells to overcome apoptosis signals and promote invasion and metastasis. This review aims to describe the major metabolic changes in diabetes and outline how cancer cells can use cellular metabolic changes to drive abnormal growth and proliferation. We will specifically examine the mechanism of metabolic reprogramming by which diabetes may promote the development of breast cancer, focusing on the role of glucose metabolism, amino acid metabolism, and lipid metabolism in this process and potential therapeutic targets. Although diabetes-associated breast cancer has always been a common health problem, research focused on finding treatments suitable for the specific needs of patients with concurrent conditions is still limited. Most studies are still currently in the pre-clinical stage and mainly focus on reprogramming the glucose metabolism. More research targeting the amino acid and lipid metabolism is needed.
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Abstract
Monoclonal antibodies are susceptible to chemical and enzymatic modifications during manufacturing, storage, and shipping. Deamidation, isomerization, and oxidation can compromise the potency, efficacy, and safety of therapeutic antibodies. Recently, in silico tools have been used to identify liable residues and engineer antibodies with better chemical stability. Computational approaches for predicting deamidation, isomerization, oxidation, glycation, carbonylation, sulfation, and hydroxylation are reviewed here. Although liable motifs have been used to improve the chemical stability of antibodies, the accuracy of in silico predictions can be improved using machine learning and molecular dynamic simulations. In addition, there are opportunities to improve predictions for specific stress conditions, develop in silico prediction of novel modifications in antibodies, and predict the impact of modifications on physical stability and antigen-binding.
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Affiliation(s)
- Shabdita Vatsa
- Development Services, Lonza Biologics, Singapore, Singapore
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4
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Daryabor G, Atashzar MR, Kabelitz D, Meri S, Kalantar K. The Effects of Type 2 Diabetes Mellitus on Organ Metabolism and the Immune System. Front Immunol 2020; 11:1582. [PMID: 32793223 PMCID: PMC7387426 DOI: 10.3389/fimmu.2020.01582] [Citation(s) in RCA: 190] [Impact Index Per Article: 47.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2020] [Accepted: 06/15/2020] [Indexed: 12/14/2022] Open
Abstract
Metabolic abnormalities such as dyslipidemia, hyperinsulinemia, or insulin resistance and obesity play key roles in the induction and progression of type 2 diabetes mellitus (T2DM). The field of immunometabolism implies a bidirectional link between the immune system and metabolism, in which inflammation plays an essential role in the promotion of metabolic abnormalities (e.g., obesity and T2DM), and metabolic factors, in turn, regulate immune cell functions. Obesity as the main inducer of a systemic low-level inflammation is a main susceptibility factor for T2DM. Obesity-related immune cell infiltration, inflammation, and increased oxidative stress promote metabolic impairments in the insulin-sensitive tissues and finally, insulin resistance, organ failure, and premature aging occur. Hyperglycemia and the subsequent inflammation are the main causes of micro- and macroangiopathies in the circulatory system. They also promote the gut microbiota dysbiosis, increased intestinal permeability, and fatty liver disease. The impaired immune system together with metabolic imbalance also increases the susceptibility of patients to several pathogenic agents such as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Thus, the need for a proper immunization protocol among such patients is granted. The focus of the current review is to explore metabolic and immunological abnormalities affecting several organs of T2DM patients and explain the mechanisms, whereby diabetic patients become more susceptible to infectious diseases.
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Affiliation(s)
- Gholamreza Daryabor
- Autoimmune Diseases Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Mohamad Reza Atashzar
- Department of Immunology, School of Medicine, Fasa University of Medical Sciences, Fasa, Iran
| | | | - Seppo Meri
- Department of Bacteriology and Immunology and the Translational Immunology Research Program (TRIMM), The University of Helsinki and HUSLAB, Helsinki University Hospital, Helsinki, Finland
| | - Kurosh Kalantar
- Department of Immunology, School of Medicine, Shiraz University of Medical Sciences, Shiraz, Iran
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5
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Kanda P, Minshull TC. Determination of glycation levels in Erwinia chrysanthemi asparaginase drug product by liquid chromatography - mass spectrometry. Eur J Pharm Sci 2020; 145:105253. [PMID: 32027934 DOI: 10.1016/j.ejps.2020.105253] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Revised: 01/09/2020] [Accepted: 02/01/2020] [Indexed: 10/25/2022]
Abstract
Erwinase (Erwinia chrysanthemi L-asparaginase) Drug Product (DP) is a freeze-dried formulation with a three-year shelf life at 2-8 °C, and an established safety, stability and efficacy profile over the more than three decades of clinical use. Seven Erwinase® DP batches, released over a 7-year period, were screened by reversed-phase liquid chromatography coupled to time-of-flight mass spectrometry for glycation levels. This modification is a known and natural consequence of exposure of Erwinase Drug Product to glucose excipients in stabilizing formulations. Although glycation is detected in current release and stability methods, glycation, including the conditions under which this reaction occurs, has not been previously characterised in detail. We have found that glycation levels of different DP lots generally correlated with age, when they were stored at low temperature. This suggests that the glycation reaction continues over time within the Drug Product formulation in the lyophilised state, even under low temperature (+2-8 °C) conditions. We were also able to examine glycation levels of one DP lot, Lot D, held under long term stability at 3 different temperatures over a 5-year period. The 2 samples held at -20 °C and -80 °C, were glycated to levels of 12% and 17%, respectively. However, the DP Lot D sample held at +2-8 oC in this time period was found to be glycated to a level of 35.6%, with multiple glycations of individual subunits observed. For analytical reference materials, it is important to keep parameters such as glycation levels as constant as possible, to avoid a 'moving target' with respect to comparisons with release and stability testing. These data suggest that storage of DP as reference standards at a lower temperature (e.g., -20 °C) can significantly reduce levels of glycation over the longer time periods required for analytical reference standards.
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Affiliation(s)
- Patrick Kanda
- Porton Biopharma Ltd., Manor Farm Road, Porton Down, Salisbury SP4 0JG, United Kingdom.
| | - Thomas C Minshull
- Porton Biopharma Ltd., Manor Farm Road, Porton Down, Salisbury SP4 0JG, United Kingdom
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Agarwal N, Mason A, Pradhan R, Kemper J, Bosley A, Serfiotis‐Mitsa D, Wang J, Lindo V, Ahuja S, Hatton D, Savery J, Miro‐Quesada G. Kinetic modeling as a tool to understand the influence of cell culture process parameters on the glycation of monoclonal antibody biotherapeutics. Biotechnol Prog 2019; 35:e2865. [DOI: 10.1002/btpr.2865] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 05/10/2019] [Accepted: 06/06/2019] [Indexed: 12/12/2022]
Affiliation(s)
- Nitin Agarwal
- Cell Culture & Fermentation SciencesMedImmune Gaithersburg Maryland
| | - Alison Mason
- Cell Culture & Fermentation SciencesMedImmune Cambridge UK
| | - Rahul Pradhan
- Cell Culture & Fermentation SciencesMedImmune Cambridge UK
| | - Jan Kemper
- Cell Culture & Fermentation SciencesMedImmune Gaithersburg Maryland
| | - Allen Bosley
- Purification Process SciencesMedImmune Gaithersburg Maryland
| | | | - Jihong Wang
- Analytical SciencesMedImmune Gaithersburg Maryland
| | - Viv Lindo
- Analytical SciencesMedImmune Cambridge UK
| | - Sanjeev Ahuja
- Cell Culture & Fermentation SciencesMedImmune Gaithersburg Maryland
| | - Diane Hatton
- Cell Culture & Fermentation SciencesMedImmune Cambridge UK
| | - James Savery
- Quantitative SciencesMedImmune Gaithersburg Maryland
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Sheffield WP, Bhakta V, Jenkins C. Extending the pre-processing holding time of whole blood beyond 48 h reduces coagulation FVIII activity and immunoglobulin G content of recovered plasma. Transfus Apher Sci 2018; 57:768-772. [PMID: 30266202 DOI: 10.1016/j.transci.2018.09.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 09/13/2018] [Accepted: 09/16/2018] [Indexed: 11/17/2022]
Abstract
BACKGROUND Plasma obtained via whole blood (WB) donation may be used either for transfusion or as recovered plasma (RP) for pooling and fractionation. In Canada, transfusable plasma must be processed within 24 h of phlebotomy, while the limit for RP processing is 72 h. We assessed the quality of RP produced by two WB processing methods and as a function of processing time. STUDY DESIGN AND METHODS RP units produced via the buffy coat method (BCM, n = 26) or whole blood filtration (WBF, n = 52) were tested for: the activities of prothrombin, fibrinogen, von Willebrand Factor (VWF), FV, FVII, and FVIII; the prothrombin time (PT); and total protein and IgG concentration. WBF RP units were evenly divided between those processed <48 h of phlebotomy (shorter-processed) or 48-72 h after phlebotomy (longer-processed). RESULTS WBF-RP did not differ significantly from BCM-RP in any tested parameter except for FV and FVIII, which exhibited mean reductions of 10.2% and 20%, respectively. Longer-processed WBF-RP did not differ significantly from shorter-processed WBF-RP in any tested parameter except for FVIII activity and IgG concentration, which exhibited mean reductions of 30.1% and 14.3%, respectively. CONCLUSIONS Canadian RP is currently fractionated into IgG, albumin, fibrinogen, and FVII/VWF concentrates irrespective of its method or time of processing. Our results supported the current approach of fractionating both BCM- and WBF-derived RP, but suggest that greater yields of immunoglobulin and FVIII/VWF products could be obtained if the maximum processing time was reduced from 72 h to 48 h.
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Affiliation(s)
- William P Sheffield
- From the Centre for Innovation of Canadian Blood Services, Hamilton, Ontario, Canada; From the Department of Pathology and Molecular Medicine, McMaster University, Hamilton, Ontario, Canada.
| | - Varsha Bhakta
- From the Centre for Innovation of Canadian Blood Services, Hamilton, Ontario, Canada
| | - Craig Jenkins
- From the Centre for Innovation of Canadian Blood Services, Ottawa, Ontario, Canada
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Wei B, Berning K, Quan C, Zhang YT. Glycation of antibodies: Modification, methods and potential effects on biological functions. MAbs 2017; 9:586-594. [PMID: 28272973 DOI: 10.1080/19420862.2017.1300214] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Glycation is an important protein modification that could potentially affect bioactivity and molecular stability, and glycation of therapeutic proteins such as monoclonal antibodies should be well characterized. Glycated protein could undergo further degradation into advance glycation end (AGE) products. Here, we review the root cause of glycation during the manufacturing, storage and in vivo circulation of therapeutic antibodies, and the current analytical methods used to detect and characterize glycation and AGEs, including boronate affinity chromatography, charge-based methods, liquid chromatography-mass spectrometry and colorimetric assay. The biological effects of therapeutic protein glycation and AGEs, which ranged from no affect to loss of activity, are also discussed.
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Affiliation(s)
- Bingchuan Wei
- a Protein Analytical Chemistry, Genentech , South San Francisco , CA , USA
| | - Kelsey Berning
- a Protein Analytical Chemistry, Genentech , South San Francisco , CA , USA
| | - Cynthia Quan
- a Protein Analytical Chemistry, Genentech , South San Francisco , CA , USA
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9
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He Z, Tong C, Sheng L, Ma M, Cai Z. Monitoring glycation-induced structural and biofunctional changes in chicken immunoglobulin Y by different monosaccharides. Poult Sci 2016; 95:2715-2723. [DOI: 10.3382/ps/pew223] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/05/2016] [Indexed: 11/20/2022] Open
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10
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Leblanc Y, Bihoreau N, Jube M, Andre MH, Tellier Z, Chevreux G. Glycation of polyclonal IgGs: Effect of sugar excipients during stability studies. Eur J Pharm Biopharm 2016; 102:185-90. [DOI: 10.1016/j.ejpb.2016.03.016] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Revised: 03/07/2016] [Accepted: 03/14/2016] [Indexed: 10/22/2022]
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11
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Hmiel LK, Brorson KA, Boyne MT. Post-translational structural modifications of immunoglobulin G and their effect on biological activity. Anal Bioanal Chem 2014; 407:79-94. [DOI: 10.1007/s00216-014-8108-x] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2014] [Revised: 08/08/2014] [Accepted: 08/11/2014] [Indexed: 12/15/2022]
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12
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Yuk IH, Zhang B, Yang Y, Dutina G, Leach KD, Vijayasankaran N, Shen AY, Andersen DC, Snedecor BR, Joly JC. Controlling glycation of recombinant antibody in fed-batch cell cultures. Biotechnol Bioeng 2011; 108:2600-10. [PMID: 21618472 DOI: 10.1002/bit.23218] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2011] [Revised: 05/10/2011] [Accepted: 05/13/2011] [Indexed: 12/27/2022]
Abstract
Protein glycation is a non-enzymatic glycosylation that can occur to proteins in the human body, and it is implicated in the pathogenesis of multiple chronic diseases. Glycation can also occur to recombinant antibodies during cell culture, which generates structural heterogeneity in the product. In a previous study, we discovered unusually high levels of glycation (>50%) in a recombinant monoclonal antibody (rhuMAb) produced by CHO cells. Prior to that discovery, we had not encountered such high levels of glycation in other in-house therapeutic antibodies. Our goal here is to develop cell culture strategies to decrease rhuMAb glycation in a reliable, reproducible, and scalable manner. Because glycation is a post-translational chemical reaction between a reducing sugar and a protein amine group, we hypothesized that lowering the concentration of glucose--the only source of reducing sugar in our fed-batch cultures--would lower the extent of rhuMAb glycation. When we decreased the supply of glucose to bioreactors from bolus nutrient and glucose feeds, rhuMAb glycation decreased to below 20% at both 2-L and 400-L scales. When we maintained glucose concentrations at lower levels in bioreactors with continuous feeds, we could further decrease rhuMAb glycation levels to below 10%. These results show that we can control glycation of secreted proteins by controlling the glucose concentration in the cell culture. In addition, our data suggest that rhuMAb glycation occurring during the cell culture process may be approximated as a second-order chemical reaction that is first order with respect to both glucose and non-glycated rhuMAb. The basic principles of this glycation model should apply to other recombinant proteins secreted during cell culture.
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Affiliation(s)
- Inn H Yuk
- Early Stage Cell Culture, Genentech, Inc., 1 DNA Way, South San Francisco, California 94080, USA.
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Monitoring nonenzymatic glycation of human immunoglobulin G by methylglyoxal and glyoxal: A spectroscopic study. Anal Biochem 2010; 408:59-63. [PMID: 20816660 DOI: 10.1016/j.ab.2010.08.038] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2010] [Revised: 08/23/2010] [Accepted: 08/27/2010] [Indexed: 12/25/2022]
Abstract
The accumulation of dicarbonyl compounds, methylglyoxal (MG) and glyoxal (G), has been observed in diabetic conditions. They are formed from nonoxidative mechanisms in anaerobic glycolysis and lipid peroxidation, and they act as advanced glycation endproduct (AGE) precursors. The objective of this study was to monitor and characterize the AGE formation of human immunoglobulin G (hIgG) by MG and G using ultraviolet (UV) and fluorescence spectroscopy, circular dichroism (CD), and matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS). hIgG was incubated over time with MG and G at different concentrations. Formation of AGE was monitored by UV and fluorescence spectroscopy. The effect of AGE formation on secondary structure of hIgG was studied by CD. Comparison of AGE profile for MG and G was performed by MALDI-MS. Both MG and G formed AGE, with MG being nearly twice as reactive as G. The combination of these techniques is a convenient method for evaluating and characterizing the AGE proteins.
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Shcheglova T, Makker S, Tramontano A. Reactive immunization suppresses advanced glycation and mitigates diabetic nephropathy. J Am Soc Nephrol 2009; 20:1012-9. [PMID: 19389854 DOI: 10.1681/asn.2008050555] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Agents that inhibit glycation end products by reducing the carbonyl load from glycation and glycoxidation are an emerging pharmacologic approach to treat complications of diabetes. We previously demonstrated that antibodies generated to the glycoprotein keyhole limpet hemocyanin (KLH) can cross-link with reactive carbonyl residues on protein conjugates. Here, we immunized streptozotocin-induced diabetic rats with KLH to assess the capacity of the elicited antibodies to intercept carbonyl residues on glycated proteins and to mitigate glycation-related pathology. Compared with diabetic rats immunized with adjuvant alone, KLH-immunized diabetic rats had decreased levels of glycated peptides in sera and demonstrated a reduction in albuminuria, proteinuria, deposition of glycation end products in the kidney, and histologic damage. In vitro, low molecular weight glycated peptides from rat serum reacted with anti-KLH antibodies at a faster rate than normal IgG and selectively modified the lambda chains. The reaction products contained peptide sequences from type I collagen alpha chain, albumin, and LDL receptor-related protein. These adduction reactions were inhibited by free KLH and by reduction of glycated peptides with borohydride. In summary, these results suggest that inherent reactivity of Ig light chains provides a natural mechanism for the removal of cytotoxic glycation products. This reactivity can be augmented by glycoprotein-specific reactive immunization, a potential biopharmaceutical approach to glycation-related pathology.
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Affiliation(s)
- Tatiana Shcheglova
- Department of Pediatrics, University of California, Davis, Medical School, One Shields Avenue, Davis, CA 95616, USA
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15
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Li Y, Cohenford MA, Dutta U, Dain JA. In vitro nonenzymatic glycation of guanosine 5'-triphosphate by dihydroxyacetone phosphate. Anal Bioanal Chem 2008; 392:1189-96. [PMID: 18791706 DOI: 10.1007/s00216-008-2365-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2008] [Revised: 08/17/2008] [Accepted: 08/20/2008] [Indexed: 01/10/2023]
Abstract
Dihydroxyacetone phosphate (DHAP) is a glycolytic intermediate that has been found to be significantly elevated in the erythrocytes of diabetic patients and patients with triosephosphate isomerase deficiency. DHAP spontaneously breaks down to methylglyoxal, a potent glycating agent that reacts with proteins and nucleic acids in vivo to form advanced glycation endproducts (AGEs). Like methylglyoxal, DHAP itself is also a glycating metabolite, capable of condensing with proteins and altering their structure or function. The objective of this investigation was to evaluate the susceptibility of nucleotides to nonenzymatic attack by DHAP, and to determine the factors influencing the rate and extent of nucleotide glycation by this sugar. Of the four nucleotide triphosphates (ATP, CTP, GTP and UTP) that were studied, only GTP was reactive, forming a wide range of UV and fluorescent products with DHAP. Increases in temperature and nucleotide concentration enhanced the rate and extent of GTP glycation by DHAP and promoted the heterogeneity of AGEs. Capillary electrophoresis, HPLC, and mass spectrometry allowed for a thorough analysis of the glycated products and demonstrated that the reaction of DHAP with GTP occurred via the classical Amadori pathway.
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Affiliation(s)
- Yuyuan Li
- Department of Chemistry, University of Rhode Island, Kingston, RI, 02881, USA
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Abstract
Heterogeneity of monoclonal antibodies is common due to the various modifications introduced over the lifespan of the molecules from the point of synthesis to the point of complete clearance from the subjects. The vast number of modifications presents great challenge to the thorough characterization of the molecules. This article reviews the current knowledge of enzymatic and nonenzymatic modifications of monoclonal antibodies including the common ones such as incomplete disulfide bond formation, glycosylation, N-terminal pyroglutamine cyclization, C-terminal lysine processing, deamidation, isomerization, and oxidation, and less common ones such as modification of the N-terminal amino acids by maleuric acid and amidation of the C-terminal amino acid. In addition, noncovalent associations with other molecules, conformational diversity and aggregation of monoclonal antibodies are also discussed. Through a complete understanding of the heterogeneity of monoclonal antibodies, strategies can be employed to better identify the potential modifications and thoroughly characterize the molecules.
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Affiliation(s)
- Hongcheng Liu
- Process Sciences Department, Abbott Bioresearch Center, 100 Research Drive, Worcester, Massachusetts 01605, USA.
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17
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Jairajpuri DS, Fatima S, Saleemuddin M. Immunoglobulin glycation with fructose: a comparative study. Clin Chim Acta 2006; 378:86-92. [PMID: 17173886 DOI: 10.1016/j.cca.2006.10.020] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2006] [Revised: 10/15/2006] [Accepted: 10/30/2006] [Indexed: 12/22/2022]
Abstract
BACKGROUND Immunoglobulins undergo non-enzymatic glycation reaction with sugars both in vivo and in vitro. Effects of glycation on the ability of the antibodies to bind antigens are contradictory. Antibodies raised in various animals may also be exposed to high concentration of sugars that are added during freeze-drying/pasteurization for preservation. METHODS IgG isolated from the sera of goat, human, rabbit, mouse, buffalo as well as IgY from hen egg yolk was subjected to in vitro glycation with fructose. The behavior of glycated IgG was investigated by SDS-PAGE, hyperchromicity at 280 nm, tryptophan fluorescence and new fluorescence. RESULTS Marked variations were observed in the response of the immunoglobulins derived from various animals to incubation with fructose. Also, incubation of anti-glucoseoxidase (GOD) antibodies with fructose resulted in a rapid loss of their ability to bind the enzyme antigen as revealed by immunodiffusion and ELISA. DETAPAC and EDTA were quite protective but were unable to completely prevent the fructose-induced alterations. CONCLUSIONS Immunoglobulins derived from goat, human, rabbit, mouse, buffalo and hen egg yolk undergo remarkable structural alterations on incubation with fructose. The susceptibility of the immunoglobulins to the modification however differed remarkably. The goat IgG was most recalcitrant while hen egg yolk IgY was most susceptible to the alterations. DETAPAC or EDTA restricted the fructose-induced alterations remarkably.
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Affiliation(s)
- Deeba S Jairajpuri
- Department of Biochemistry, Aligarh Muslim University, Aligarh 202002, India
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