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Tariq Ghayur - One of the best experts on this subject based on the ideXlab platform.
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the structure of dual Variable Domain immunoglobulin molecules alone and bound to antigen
mAbs, 2013Co-Authors: Ivan Correia, Tariq Ghayur, Clarissa G Jakob, Joyce J Sung, Randall E Burton, Bridget Carragher, Czeslaw RadziejewskiAbstract:A dual-specific, tetravalent immunoglobulin G-like molecule, termed dual Variable Domain immunoglobulin (DVD-Ig™), is engineered to block two targets. Flexibility modulates Fc receptor and complement binding, but could result in undesirable cross-linking of surface antigens and downstream signaling. Understanding the flexibility of parental mAbs is important for designing and retaining functionality of DVD-Ig™ molecules. The architecture and dynamics of a DVD-Ig™ molecule and its parental mAbs was examined using single particle electron microscopy. Hinge angles measured for the DVD-Ig™ molecule were similar to the inner antigen parental mAb. The outer binding Domain of the DVD-Ig™ molecule was highly mobile and three-dimensional (3D) analysis showed binding of inner antigen caused the outer Domain to fold out of the plane with a major morphological change. Docking high-resolution X-ray structures into the 3D electron microscopy map supports the extraordinary Domain flexibility observed in the DVD-Ig™ molecule allowing antigen binding with minimal steric hindrance.
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structure reveals function of the dual Variable Domain immunoglobulin dvd ig molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
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Structure reveals function of the dual Variable Domain immunoglobulin (DVD-Ig™) molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
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Generation of dual-Variable-Domain immunoglobulin molecules for dual-specific targeting.
Methods in Enzymology, 2011Co-Authors: Tariq GhayurAbstract:Bispecific antibodies may be used to improve clinical efficacy by targeting two disease mechanisms for the treatment of complex human diseases in a single agent. Bispecific antibodies also hold promise for certain therapeutic applications difficult to achieve by single-targeting monospecific antibodies, such as immune (T cell or NK) cell retargeting, site-specific targeting, enabling therapeutics to cross the blood-brain barrier, and unique receptor modulation. Although the history of bispecific antibody research is almost as long as hybridoma technology, it is not until recent that bispecific antibodies have made substantial breakthrough, thanks to promising clinical trial results of a few bispecific antibodies and the development of new formats which largely ease manufacturing and physicochemical property challenges encountered by early bispecific antibody formats. The dual-Variable-Domain immunoglobulin (DVD-Ig™) format was initially described in 2007. In this format, the target-binding Variable Domains of two monoclonal antibodies can be combined via naturally occurring linkers to create a tetravalent, dual-targeting single agent. Viable DVD-Ig molecules can be identified through optimization of antibody pair, antibody Variable Domain orientation, and linkers. An optimized DVD-Ig™ molecule has many desirable properties of a mAb, such as good expression in mammalian cells, easy purification to homogeneity using standard approaches, displaying good drug-like biophysical and pharmacokinetic properties, and amenability to large-scale manufacturing. Several DVD-Ig molecules have demonstrated favorable pharmacokinetic properties and efficacy in preclinical animal models. Here, we provide an example of construction and preliminary characterization of a DVD-Ig™ molecule and discuss the general approach used in optimization.
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Ligand association rates to the inner-Variable-Domain of a dual-Variable-Domain immunoglobulin are significantly impacted by linker design.
mAbs, 2011Co-Authors: Enrico L. Digiammarino, John E. Harlan, Karl A. Walter, Uri S. Ladror, Rohinton Edalji, Charles W. Hutchins, Marc R. Lake, Amy Greischar, Liu Junjian, Tariq GhayurAbstract:The DVD-IgTM protein is a dual-specific immunoglobulin. Each of the two arms of the molecule contains two Variable Domains, an inner Variable Domain and an outer Variable Domain linked in tandem, each with binding specificity for different targets or epitopes. One area of on-going research involves determining how the proximity of the outer Variable Domain affects the binding of ligands to the inner Variable Domain. To explore this area, we prepared a series of DVD-Ig proteins with binding specificities toward TNFα and an alternate therapeutic target. Kinetic measurements of TNFα binding to this series of DVD-Ig proteins were used to probe the effects of Variable Domain position and linker design on ligand on- and off-rates. We found that affinities for TNFα are generally lower when binding to the inner Domain than to the outer Domain and that this loss of affinity is primarily due to reduced association rate. This effect could be mitigated, to some degree, by linker design. We show several linker sequenc...
Martina Daňková - One of the best experts on this subject based on the ideXlab platform.
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Variable-Domain fuzzy sets—Part II: Apparatus
Fuzzy Sets and Systems, 2020Co-Authors: Libor Běhounek, Martina DaňkováAbstract:Abstract This is the second part of a two-part paper on operations on fuzzy sets that may not share the same Domain of definition. Part I described several ways of representing Variable-Domain fuzzy sets and introduced a few basic Variable-Domain fuzzy set operations. The present (largely self-contained) Part II further develops the theory of Variable-Domain fuzzy sets, based primarily on the representation of Variable Domains by a dummy membership degree that indicates the out-of-Domain assignment error. We first describe several families of algebraic operations on the extended set of membership degrees; these are later employed in the investigation of basic notions of Variable-Domain fuzzy set theory. The fuzzy set operations studied in this paper include Variable-Domain variants of unions and intersections, kernels and supports, heights and plinths, equalities and inclusions, Cartesian products, and fuzzy relational compositions. Besides the initial examination of these Variable-Domain notions, our aim is to demonstrate the viability of Variable-Domain fuzzy set theory and highlight the similarity as well as differences between the fixed- and Variable-Domain treatments of fuzzy sets.
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Variable-Domain fuzzy sets—Part I: Representation
Fuzzy Sets and Systems, 2020Co-Authors: Libor Běhounek, Martina DaňkováAbstract:Abstract Despite the fact that fuzzy sets can generally have different Domains, standard definitions of fuzzy set operations assume a common reference set for all their operands. The usual way to satisfy this precondition is to assign zero membership to elements outside the Domain of each operand. In Part I of this two-part paper we point out several issues with this method and argue that keeping track of the original Domains is necessary to ensure the intended behavior of numerous fuzzy set operations. We discuss several ways of representing fuzzy sets with Variable Domains, preparing the grounds for the apparatus of Variable-Domain fuzzy set theory described in Part II of the paper.
Clarissa G Jakob - One of the best experts on this subject based on the ideXlab platform.
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the structure of dual Variable Domain immunoglobulin molecules alone and bound to antigen
mAbs, 2013Co-Authors: Ivan Correia, Tariq Ghayur, Clarissa G Jakob, Joyce J Sung, Randall E Burton, Bridget Carragher, Czeslaw RadziejewskiAbstract:A dual-specific, tetravalent immunoglobulin G-like molecule, termed dual Variable Domain immunoglobulin (DVD-Ig™), is engineered to block two targets. Flexibility modulates Fc receptor and complement binding, but could result in undesirable cross-linking of surface antigens and downstream signaling. Understanding the flexibility of parental mAbs is important for designing and retaining functionality of DVD-Ig™ molecules. The architecture and dynamics of a DVD-Ig™ molecule and its parental mAbs was examined using single particle electron microscopy. Hinge angles measured for the DVD-Ig™ molecule were similar to the inner antigen parental mAb. The outer binding Domain of the DVD-Ig™ molecule was highly mobile and three-dimensional (3D) analysis showed binding of inner antigen caused the outer Domain to fold out of the plane with a major morphological change. Docking high-resolution X-ray structures into the 3D electron microscopy map supports the extraordinary Domain flexibility observed in the DVD-Ig™ molecule allowing antigen binding with minimal steric hindrance.
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structure reveals function of the dual Variable Domain immunoglobulin dvd ig molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
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Structure reveals function of the dual Variable Domain immunoglobulin (DVD-Ig™) molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
Libor Běhounek - One of the best experts on this subject based on the ideXlab platform.
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Variable-Domain fuzzy sets—Part II: Apparatus
Fuzzy Sets and Systems, 2020Co-Authors: Libor Běhounek, Martina DaňkováAbstract:Abstract This is the second part of a two-part paper on operations on fuzzy sets that may not share the same Domain of definition. Part I described several ways of representing Variable-Domain fuzzy sets and introduced a few basic Variable-Domain fuzzy set operations. The present (largely self-contained) Part II further develops the theory of Variable-Domain fuzzy sets, based primarily on the representation of Variable Domains by a dummy membership degree that indicates the out-of-Domain assignment error. We first describe several families of algebraic operations on the extended set of membership degrees; these are later employed in the investigation of basic notions of Variable-Domain fuzzy set theory. The fuzzy set operations studied in this paper include Variable-Domain variants of unions and intersections, kernels and supports, heights and plinths, equalities and inclusions, Cartesian products, and fuzzy relational compositions. Besides the initial examination of these Variable-Domain notions, our aim is to demonstrate the viability of Variable-Domain fuzzy set theory and highlight the similarity as well as differences between the fixed- and Variable-Domain treatments of fuzzy sets.
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Variable-Domain fuzzy sets—Part I: Representation
Fuzzy Sets and Systems, 2020Co-Authors: Libor Běhounek, Martina DaňkováAbstract:Abstract Despite the fact that fuzzy sets can generally have different Domains, standard definitions of fuzzy set operations assume a common reference set for all their operands. The usual way to satisfy this precondition is to assign zero membership to elements outside the Domain of each operand. In Part I of this two-part paper we point out several issues with this method and argue that keeping track of the original Domains is necessary to ensure the intended behavior of numerous fuzzy set operations. We discuss several ways of representing fuzzy sets with Variable Domains, preparing the grounds for the apparatus of Variable-Domain fuzzy set theory described in Part II of the paper.
Enrico L. Digiammarino - One of the best experts on this subject based on the ideXlab platform.
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Structure reveals function of the dual Variable Domain immunoglobulin (DVD-Ig™) molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
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structure reveals function of the dual Variable Domain immunoglobulin dvd ig molecule
mAbs, 2013Co-Authors: Clarissa G Jakob, Enrico L. Digiammarino, Rohinton Edalji, Russell A Judge, Tariq GhayurAbstract:Several bispecific antibody-based formats have been developed over the past 25 years in an effort to produce a new generation of immunotherapeutics that target two or more disease mechanisms simultaneously. One such format, the dual-Variable Domain immunoglobulin (DVD-Ig™), combines the target binding Domains of two monoclonal antibodies via flexible naturally occurring linkers, which yields a tetravalent IgG - like molecule. We report the structure of an interleukin (IL)12-IL18 DVD-Ig™ Fab (DFab) fragment with IL18 bound to the inner Variable Domain (VD) that reveals the remarkable flexibility of the DVD-Ig™ molecule and how the DVD-Ig™ format can function to bind four antigens simultaneously. An understanding of how the inner Variable Domain retains function is of critical importance for designing DVD-Ig™ molecules, and for better understanding of the flexibility of immunoglobulin Variable Domains and linkers, which may aid in the design of improved bi- and multi-specific biologics in general.
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Ligand association rates to the inner-Variable-Domain of a dual-Variable-Domain immunoglobulin are significantly impacted by linker design.
mAbs, 2011Co-Authors: Enrico L. Digiammarino, John E. Harlan, Karl A. Walter, Uri S. Ladror, Rohinton Edalji, Charles W. Hutchins, Marc R. Lake, Amy Greischar, Liu Junjian, Tariq GhayurAbstract:The DVD-IgTM protein is a dual-specific immunoglobulin. Each of the two arms of the molecule contains two Variable Domains, an inner Variable Domain and an outer Variable Domain linked in tandem, each with binding specificity for different targets or epitopes. One area of on-going research involves determining how the proximity of the outer Variable Domain affects the binding of ligands to the inner Variable Domain. To explore this area, we prepared a series of DVD-Ig proteins with binding specificities toward TNFα and an alternate therapeutic target. Kinetic measurements of TNFα binding to this series of DVD-Ig proteins were used to probe the effects of Variable Domain position and linker design on ligand on- and off-rates. We found that affinities for TNFα are generally lower when binding to the inner Domain than to the outer Domain and that this loss of affinity is primarily due to reduced association rate. This effect could be mitigated, to some degree, by linker design. We show several linker sequenc...
