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Singh PK, Stan RC. Rheumatoid arthritis autoantibodies benefit from inflammation temperatures. Int Immunopharmacol 2024; 129:111690. [PMID: 38354510 DOI: 10.1016/j.intimp.2024.111690] [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: 11/13/2023] [Revised: 01/23/2024] [Accepted: 02/09/2024] [Indexed: 02/16/2024]
Abstract
BACKGROUND Symptoms of rheumatoid arthritis are associated with local inflammation and may include low-grade fever. OBJECTIVE To establish the role of fever/inflammation temperatures (38℃-39℃) on the activity of autoantibodies and therapeutic antibodies relevant for rheumatoid arthritis. METHODS Through the use of molecular dynamics and free energy calculations, we investigated the role of temperature on the formation of pertinent immune complexes. RESULTS Rheumatoid arthritis autoantibodies bind with higher affinity at febrile/inflammation temperatures. CONCLUSIONS Fever may modulate binding affinity of autoantibodies relevant for rheumatoid arthritis.
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Affiliation(s)
- Puneet K Singh
- Puneet K. Singh - Department of Basic Medical Science, Chonnam National University, Hwasun 58128, Republic of Korea
| | - Razvan C Stan
- Puneet K. Singh - Department of Basic Medical Science, Chonnam National University, Hwasun 58128, Republic of Korea.
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2
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Bergonzo C, Hoopes JT, Kelman Z, Gallagher DT. Effects of glycans and hinge on dynamics in the IgG1 Fc. J Biomol Struct Dyn 2023:1-9. [PMID: 37897185 PMCID: PMC11055941 DOI: 10.1080/07391102.2023.2270749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2023] [Accepted: 10/08/2023] [Indexed: 10/29/2023]
Abstract
The crystallizable fragment (Fc) domain of immunoglobulin subclass IgG1 antibodies is engineered for a wide variety of pharmaceutical applications. Two important structural variables in Fc constructs are the hinge region connecting the Fc to the antigen binding fragments (Fab) and the glycans present in various glycoforms. These components affect receptor binding interactions that mediate immune activation. To design new antibody drugs, a robust in silico method for linking stability to structural changes is necessary. In this work, all-atom simulations were used to compare the dynamic behavior of the four structural variants arising from presence or absence of the hinge and glycans. We expressed the simplest of these constructs, the 'minimal Fc' with no hinge and no glycans, in Escherichia coli and report its crystal structure. The 'maximal Fc' that includes full hinge and G0F/G1F glycans is based on a previously reported structure, Protein Data Bank (PDB) ID: 5VGP. These, along with two intermediate structures (with only the glycans or with only the hinge) were used to independently measure the stability effects of the two structural variables using umbrella sampling simulations. Principal component analysis (PCA) was used to determine free energy effects along the Fc's dominant mode of motion. This work provides a comprehensive picture of the effects of hinge and glycans on Fc dynamics and stability.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Christina Bergonzo
- National Institute of Standards and Technology, 9600 Gudelsky Dr. Rockville, MD, 20850
- The Institute for Bioscience and Biotechnology Research, 9600 Gudelsky Dr. Rockville, MD, 20850
| | - J. Todd Hoopes
- The Institute for Bioscience and Biotechnology Research, 9600 Gudelsky Dr. Rockville, MD, 20850
- The Biomolecular Labeling Laboratory, 9600 Gudelsky Dr. Rockville, MD, 20850
| | - Zvi Kelman
- National Institute of Standards and Technology, 9600 Gudelsky Dr. Rockville, MD, 20850
- The Institute for Bioscience and Biotechnology Research, 9600 Gudelsky Dr. Rockville, MD, 20850
- The Biomolecular Labeling Laboratory, 9600 Gudelsky Dr. Rockville, MD, 20850
| | - D. Travis Gallagher
- National Institute of Standards and Technology, 9600 Gudelsky Dr. Rockville, MD, 20850
- The Institute for Bioscience and Biotechnology Research, 9600 Gudelsky Dr. Rockville, MD, 20850
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3
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Sastyarina Y, Firdaus ARR, Nafisah Z, Hardianto A, Yusuf M, Ramli M, Mutalib A, Soedjanaatmadja UM. Modeling and Molecular Dynamic Simulation of F(ab') 2 Fragment of Nimotuzumab for Lung Cancer Diagnostics. Bioinform Biol Insights 2022; 15:11779322211002174. [PMID: 35173422 PMCID: PMC8842462 DOI: 10.1177/11779322211002174] [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: 08/02/2020] [Accepted: 02/22/2021] [Indexed: 01/03/2023] Open
Abstract
Lung cancer is one of the leading causes of cancer-related deaths in the world among both men and women. Several studies in the literature report that overexpression and mutation of the epidermal growth factor receptor (EGFR) are implicated in the pathogenesis of some lung cancers. Nimotuzumab is a humanized monoclonal antibody (mAb) that inhibits EGF binding because it binds to the extracellular domain of the EGFR. Nimotuzumab requires bivalent binding for stable attachment to cellular surface, which leads to nimotuzumab selectively binding to cells that express mAbs of moderate to high EGFR levels, and this could explain its low toxicity. This property has an advantage for development of nimotuzumab as a therapeutic and diagnostic agent. Monoclonal antibodies are large in size (150 kDa), thus penetrating slowly and residing in the blood for extended periods of time (from days to weeks); their use in imaging studies can result in low signal-to-background ratios and poor image quality. A reduction in the size of the immunoglobulin molecule has also been proposed as a means for increasing tumor penetration by mAbs. Nevertheless, it is known that the penetration of mAb into tumor cell is slow, due to its high molecular weight. Therefore, mAb is not very attractive to be used for imaging diagnostic purpose because of its kinetics and potential to elicit antibody response. The objective of this research was to study the homology modeling of a simpler functional molecule based on nimotuzumab, which consists of 2 antigen-binding fragments (Fab), namely, F(ab′)2, using MODELER. The crystal structure of Fab of nimotuzumab from protein data bank was used as a template to construct the model of F(ab′)2. Molecular dynamic simulation was performed to evaluate the stability of F(ab′)2 and conformational changes of F(ab′)2 in simulation. The result showed the dynamic behavior of antigen-binding site region of F(ab′)2 throughout simulation. This result is expected to be useful in the further development of F(ab′)2 fragment nimotuzumab as a lung cancer diagnostic.
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Affiliation(s)
| | - Ade Rizqi Ridwan Firdaus
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
| | - Zuhrotun Nafisah
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
| | - Ari Hardianto
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
| | - Muhammad Yusuf
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
| | - Martalena Ramli
- Center for Radioisotopes and Radiopharmaceutical Tehnology, National Nuclear Agency (BATAN) Puspitek-Serpong, Tangerang, Indonesia
| | - Abdul Mutalib
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
| | - Ukun Ms Soedjanaatmadja
- Department of Chemistry, Faculty of Mathematics and Natural Science, Universitas Padjadjaran, Bandung, Indonesia
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4
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Tomar DS, Licari G, Bauer J, Singh SK, Li L, Kumar S. Stress-dependent flexibility of a full-length human monoclonal antibody: Insights from molecular dynamics to support biopharmaceutical development. J Pharm Sci 2021; 111:628-637. [PMID: 34742728 DOI: 10.1016/j.xphs.2021.10.039] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2021] [Revised: 10/30/2021] [Accepted: 10/30/2021] [Indexed: 01/15/2023]
Abstract
After several decades of advancements in drug discovery, product development of biopharmaceuticals remains a time- and resource-consuming endeavor. One of the main reasons is associated to the lack of fundamental understanding of conformational dynamics of such biologic entities, and how they respond to various stresses encountered during manufacturing. In this work, we have studied the conformational dynamics of human IgG1κ b12 monoclonal antibody (mAb) using molecular dynamics simulations. The hundreds of nanoseconds long trajectories reveal that b12 mAb is highly flexible. Its variable domains show greater conformational fluctuations than the constant domains. Additionally, it collapses towards a more globular shape in response to thermal stress, leading to decrease in the total solvent exposed surface area and radius of gyration. This behavior is more pronounced for the deglycosylated b12 mAb, and it appears to correlate with increase in inter-domain contacts between specific regions of the antibody. Conformational fluctuations also cause temporary formation and disruption of hydrophobic and charged patches on the antibody surface, which is particularly important for the prediction of CMC properties during development phases of antibody-based biotherapeutics. The insights gained through these simulations may help the development of biologic drugs, especially with regards to manufacturing processes where antibodies may undergo significant thermal stress.
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Affiliation(s)
- Dheeraj S Tomar
- Biotherapeutics Pharmaceutical Sciences Research and Development, Pfizer Inc., 700 Chesterfield Parkway West, Chesterfield, MO, 63017, USA
| | - Giuseppe Licari
- Pharmaceuticals Development Biologicals, Boehringer Ingelheim Pharmaceuticals, Inc., D-88397 Biberach an der Riss, Germany
| | - Joschka Bauer
- Pharmaceuticals Development Biologicals, Boehringer Ingelheim Pharmaceuticals, Inc., D-88397 Biberach an der Riss, Germany
| | - Satish K Singh
- Biotherapeutics Pharmaceutical Sciences Research and Development, Pfizer Inc., 700 Chesterfield Parkway West, Chesterfield, MO, 63017, USA
| | - Li Li
- Biotherapeutics Pharmaceutical Sciences Research and Development, Pfizer Inc., 1 Burtt Road, Andover, Massachusetts, 01810, USA
| | - Sandeep Kumar
- Biotherapeutics Discovery, Boehringer Ingelheim Pharmaceuticals, Inc., 900 Ridgebury Road, Ridgefield, CT 06877.
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5
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Göritzer K, Strasser R. Glycosylation of Plant-Produced Immunoglobulins. EXPERIENTIA SUPPLEMENTUM (2012) 2021; 112:519-543. [PMID: 34687021 DOI: 10.1007/978-3-030-76912-3_16] [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] [Indexed: 06/13/2023]
Abstract
Many economically important protein-based therapeutics like monoclonal antibodies are glycosylated. Due to the recognized importance of this type of posttranslational modification, glycoengineering of expression systems to obtain highly active and homogenous therapeutics is an emerging field. Although most of the monoclonal antibodies on the market are still produced in mammalian expression platforms, plants are emerging as an alternative cost-effective and scalable production platform that allows precise engineering of glycosylation to produce targeted human glycoforms at large homogeneity. Apart from producing more effective antibodies, pure glycoforms are required in efforts to link biological functions to specific glycan structures. Much is already known about the role of IgG1 glycosylation and this antibody class is the dominant recombinant format that has been expressed in plants. By contrast, little attention has been paid to the glycoengineering of recombinant IgG subtypes and the other four classes of human immunoglobulins (IgA, IgD, IgE, and IgM). Except for IgD, all these antibody classes have been expressed in plants and the glycosylation has been analyzed in a site-specific manner. Here, we summarize the current data on glycosylation of plant-produced monoclonal antibodies and discuss the findings in the light of known functions for these glycans.
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Affiliation(s)
| | - Richard Strasser
- University of Natural Resources and Life Sciences Vienna, Vienna, Austria.
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6
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Rathore AS, Sarker A, Gupta RD. Designing antibody against highly conserved region of dengue envelope protein by in silico screening of scFv mutant library. PLoS One 2019; 14:e0209576. [PMID: 30629625 PMCID: PMC6328183 DOI: 10.1371/journal.pone.0209576] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2018] [Accepted: 12/07/2018] [Indexed: 02/08/2023] Open
Abstract
Dengue being one of the deadliest diseases of tropical regions, enforces to put continuous efforts for the development of vaccine and effective therapeutics. Most of the antibodies generated during dengue infection are non-neutralizing and cause antibody dependent enhancement. Hence, making a potent neutralizing antibody against all four dengue serotypes could be very effective for the treatment. However, designing a single antibody for all serotypes is difficult due to variation in protein sequences. Therefore, the objective is to identify conserved region of dengue envelope protein and then develop an antibody against that conserved region. Before advancing to the development of such an antibody, it is desirable to validate the interactions between antibody and dengue envelope protein. In silico analysis of such interactions provides a good platform to find out a suitable region to design and construct an antibody against it by analyzing antigen-antibody interaction before synthesizing the antibody. In this study, two highly conserved regions of dengue envelope protein were identified and an scFv was constructed against it. Both scFv and FuBc proteins were expressed in bacterial expression system and binding efficiency was analyzed by SPR analysis with KD value 2.3 μM. In order to improve binding efficiency, an in silico scFv mutant library was created which was virtually screened for higher binding efficiency. Six mutants with high binding efficiency were selected for further analysis. The binding ability of these mutants were predicted using simulation analysis which shows these mutations were stabilizing scFv-FuBc complex.
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Affiliation(s)
| | - Animesh Sarker
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, India
| | - Rinkoo Devi Gupta
- Faculty of Life Sciences and Biotechnology, South Asian University, New Delhi, India
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Thinking outside the Laboratory: Analyses of Antibody Structure and Dynamics within Different Solvent Environments in Molecular Dynamics (MD) Simulations. Antibodies (Basel) 2018; 7:antib7030021. [PMID: 31544873 PMCID: PMC6640683 DOI: 10.3390/antib7030021] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2018] [Revised: 06/11/2018] [Accepted: 06/20/2018] [Indexed: 11/17/2022] Open
Abstract
Monoclonal antibodies (mAbs) have revolutionized the biomedical field, directly influencing therapeutics and diagnostics in the biopharmaceutical industry, while continuing advances in computational efficiency have enabled molecular dynamics (MD) simulations to provide atomistic insight into the structure and function of mAbs. Despite the success of MD tools, further optimizations are still required to enhance the computational efficiency of complex mAb simulations. This issue can be tackled by changing the way the solvent system is modelled to reduce the number of atoms to be tracked but must be done without compromising the accuracy of the simulations. In this work, the structure of the IgG2a antibody was analyzed in three solvent systems: explicit water and ions, implicit water and ions, and implicit water and explicit ions. Root-mean-square distance (RMSD), root-mean-square fluctuations (RMSF), and interchain angles were used to quantify structural changes. The explicit system provides the most atomistic detail but is ~6 times slower in its exploration of configurational space and required ~4 times more computational time on our supercomputer than the implicit simulations. Overall, the behavior of the implicit and explicit simulations is quantifiably similar, with the inclusion of explicit ions in the implicit simulation stabilizing the antibody to reproduce well the statistical fluctuations of the fully explicit system. Therefore, this approach holds promise to maximize the use of computational resources to explore antibody behavior.
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Abstract
The crystallizable fragment (Fc) of the immunoglobulin class G (IgG) is a very attractive scaffold for the design of novel therapeutics due to its quality of uniting all essential antibody functions. This article reviews the functionalization of this homodimeric glycoprotein by diversification of structural loops of CH3 domains for the design of Fcabs, i.e. antigen-binding Fc proteins. It reports the design of libraries for the selection of nanomolar binders with wildtype-like in vivo half-life and correlation of Fc receptor binding and ADCC. The in vitro and preclinical biological activity of selected Fcabs is compared with that of clinically approved antibodies. Recently, the great potential of the scaffold for the development of therapeutics for clinical use has been shown when the HER2-binding Fcab FS102 entered clinical phase I. Furthermore, methods for the engineering of biophysical properties of Fcabs applicable to proteins in general are presented as well as the different approaches in the design of heterodimeric Fc-based scaffolds used in the generation of bispecific monoclonal antibodies. Finally, this work critically analyzes and compares the various efforts in the design of highly diverse and functional libraries that have been made in the engineering of IgG1-Fc and structurally similar scaffolds.
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Affiliation(s)
- Elisabeth Lobner
- Christian Doppler Laboratory for Antibody Engineering, Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Michael W Traxlmayr
- Christian Doppler Laboratory for Antibody Engineering, Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Christian Obinger
- Christian Doppler Laboratory for Antibody Engineering, Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
| | - Christoph Hasenhindl
- Christian Doppler Laboratory for Antibody Engineering, Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
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9
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Castilho A, Gruber C, Thader A, Oostenbrink C, Pechlaner M, Steinkellner H, Altmann F. Processing of complex N-glycans in IgG Fc-region is affected by core fucosylation. MAbs 2016; 7:863-70. [PMID: 26067753 DOI: 10.1080/19420862.2015.1053683] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
We investigated N-glycan processing of immunoglobulin G1 using the monoclonal antibody cetuximab (CxMab), which has a glycosite in the Fab domain in addition to the conserved Fc glycosylation, as a reporter. Three GlcNAc (Gn) terminating bi-antennary glycoforms of CxMab differing in core fucosylation (α1,3- and α1,6-linkage) were generated in a plant-based expression platform. These GnGn, GnGnF(3), and GnGnF(6) CxMab variants were subjected in vivo to further processing toward sialylation and GlcNAc diversification (bisected and branching structures). Mass spectrometry-based glycan analyses revealed efficient processing of Fab glycans toward envisaged structures. By contrast, Fc glycan processing largely depend on the presence of core fucose. A particularly strong support of glycan processing in the presence of plant-specific core α1,3-fucose was observed. Consistently, molecular modeling suggests changes in the interactions of the Fc carbohydrate chain depending on the presence of core fucose, possibly changing the accessibility. Here, we provide data that reveal molecular mechanisms of glycan processing of IgG antibodies, which may have implications for the generation of glycan-engineered therapeutic antibodies with improved efficacies.
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Affiliation(s)
- Alexandra Castilho
- a Department of Applied Genetics and Cell Biology ; University of Natural Resources and Life Sciences ; Vienna , Austria
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Traxlmayr MW, Lobner E, Hasenhindl C, Stadlmayr G, Oostenbrink C, Rüker F, Obinger C. Construction of pH-sensitive Her2-binding IgG1-Fc by directed evolution. Biotechnol J 2015; 9:1013-22. [PMID: 24964247 PMCID: PMC4314675 DOI: 10.1002/biot.201300483] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2013] [Revised: 05/05/2014] [Accepted: 06/23/2014] [Indexed: 01/17/2023]
Abstract
For most therapeutic proteins, a long serum half-life is desired. Studies have shown that decreased antigen binding at acidic pH can increase serum half-life. In this study, we aimed to investigate whether pH-dependent binding sites can be introduced into antigen binding crystallizable fragments of immunoglobulin G1 (Fcab). The C-terminal structural loops of an Fcab were engineered for reduced binding to the extracellular domain of human epidermal growth factor receptor 2 (Her2-ECD) at pH 6 compared to pH 7.4. A yeast-displayed Fcab-library was alternately selected for binding at pH 7.4 and non-binding at pH 6.0. Selected Fcab variants showed clear pH-dependent binding to soluble Her2-ECD (decrease in affinity at pH 6.0 compared to pH 7.4) when displayed on yeast. Additionally, some solubly expressed variants exhibited pH-dependent interactions with Her2-positive cells whereas their conformational and thermal stability was pH-independent. Interestingly, two of the three Fcabs did not contain a single histidine mutation but all of them contained variations next to histidines that already occurred in loops of the lead Fcab. The study demonstrates that yeast surface display is a valuable tool for directed evolution of pH-dependent binding sites in proteins.
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Affiliation(s)
- Michael W Traxlmayr
- Christian Doppler Laboratory for Antibody Engineering at Department of Chemistry and Department of Biotechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria; Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Vienna, Austria
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11
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Hasenhindl C, Lai B, Delgado J, Traxlmayr MW, Stadlmayr G, Rüker F, Serrano L, Oostenbrink C, Obinger C. Creating stable stem regions for loop elongation in Fcabs - insights from combining yeast surface display, in silico loop reconstruction and molecular dynamics simulations. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2014; 1844:1530-40. [PMID: 24792385 PMCID: PMC4118681 DOI: 10.1016/j.bbapap.2014.04.020] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Revised: 04/01/2014] [Accepted: 04/24/2014] [Indexed: 11/05/2022]
Abstract
Fcabs (Fc antigen binding) are crystallizable fragments of IgG where the C-terminal structural loops of the CH3 domain are engineered for antigen binding. For the design of libraries it is beneficial to know positions that will permit loop elongation to increase the potential interaction surface with antigen. However, the insertion of additional loop residues might impair the immunoglobulin fold. In the present work we have probed whether stabilizing mutations flanking the randomized and elongated loop region improve the quality of Fcab libraries. In detail, 13 libraries were constructed having the C-terminal part of the EF loop randomized and carrying additional residues (1, 2, 3, 5 or 10, respectively) in the absence and presence of two flanking mutations. The latter have been demonstrated to increase the thermal stability of the CH3 domain of the respective solubly expressed proteins. Assessment of the stability of the libraries expressed on the surface of yeast cells by flow cytometry demonstrated that loop elongation was considerably better tolerated in the stabilized libraries. By using in silico loop reconstruction and mimicking randomization together with MD simulations the underlying molecular dynamics were investigated. In the presence of stabilizing stem residues the backbone flexibility of the engineered EF loop as well as the fluctuation between its accessible conformations were decreased. In addition the CD loop (but not the AB loop) and most of the framework regions were rigidified. The obtained data are discussed with respect to the design of Fcabs and available data on the relation between flexibility and affinity of CDR loops in Ig-like molecules. Characterization of EF loop libraries of IgG1-Fc displayed on yeast surface. Artificial stable stem regions increase tolerance to amino acid insertions. Combination of in silico loop elongation with MD simulations. Analysis of loop dynamics and conformational variability. Pronounced impact of loop stabilization on domain and loop dynamics.
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Affiliation(s)
- Christoph Hasenhindl
- Christian Doppler Laboratory for Antibody Engineering, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Balder Lai
- Institute of Molecular Modeling and Simulation, Department of Material Sciences and Process Engineering, BOKU - University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Javier Delgado
- Design of Biological Systems, Systems Biology Research Unit, Centre for Genomic Regulation-CRG, UPF, 08003 Barcelona, Spain
| | - Michael W Traxlmayr
- Christian Doppler Laboratory for Antibody Engineering, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Gerhard Stadlmayr
- Christian Doppler Laboratory for Antibody Engineering, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Florian Rüker
- Christian Doppler Laboratory for Antibody Engineering, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department of Biotechnology, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria
| | - Luis Serrano
- Design of Biological Systems, Systems Biology Research Unit, Centre for Genomic Regulation-CRG, UPF, 08003 Barcelona, Spain
| | - Chris Oostenbrink
- Institute of Molecular Modeling and Simulation, Department of Material Sciences and Process Engineering, BOKU - University of Natural Resources and Life Sciences, A-1190 Vienna, Austria
| | - Christian Obinger
- Christian Doppler Laboratory for Antibody Engineering, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria; Department of Chemistry, Vienna Institute of BioTechnology, BOKU - University of Natural Resources and Life Sciences, Muthgasse 18, A-1190 Vienna, Austria.
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