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Oxidative stress in a biological system is often defined as a redox imbalance within cells or groups of cells within an organism. Reductive-oxidative (redox) imbalances in cellular systems have been implicated in several diseases such as cancer. To better
This paper summarises the proceedings of a workshop held at Trinity Hall, Cambridge to discuss comparability and includes additional information and references to related information added subsequent to the workshop. Comparability is the need to
Vishnu Dharmaraj, P. Douglas Godfrin, Yun Liu, Steven Hudson
High viscosity is a major challenge with protein therapeutics at extremely high concentration. Understanding the relationship between the concentration of a protein solution and its viscosity as a function of shear rate and temperature is therefore
Carl G. Simon Jr., Anne L. Plant, Sumona Sarkar, John T. Elliott, Sheng Lin-Gibson
Cell therapy products (CTPs) need quantitative, validated, and robust assays to support informed decision making during their development, manufacturing, and regulation. These products, the materials involved in their production and the methods for
Kiran Bhadriraju, Michael Halter, Julien M. Amelot, Peter Bajcsy, Joe Chalfoun, Antoine Vandecreme, Barbara Mallon, Kye-yoon Park, John T. Elliott, Subhash Sista, Anne L. Plant
Identification of critical characteristics of therapeutically active cells, and quantification of those characteristics, are essential for assuring consistency and potency of cell therapy products. We have developed image analysis and visualization
Qian Dong, Xinjian Yan, Yuxue Liang, Stephen E. Stein
This work presents a detailed analysis of glycopeptides produced in the tryptic digestion of an IgG biologic drug reference material. Analysis was done by nanospray ESI LC-MS/MS over a wide range of HCD collision energies with both conventional 1D
Understanding shear thickening presents a significant challenge in colloidal physics. As the applied shear pushes particles into close contact, the macroscopic rheology is increasingly controlled by the microscopic details of short ranged particle
Peter Bajcsy, Mylene H. Simon, Stephen J. Florczyk, Carl G. Simon Jr., Derek Juba, Mary C. Brady
We address the problem of estimating 3D segmentation performance when segmentation is applied to thousands of confocal microscopy images (z-stacks) of cells. With a very large number of z-stacks, manual inputs to validate each segmentation result are
Jeffrey W. Hudgens, Richard Y. Huang, Emma D'Ambro
The chapter examines method validation and measurement standards for measuring protein dynamics by hydrogen/deuterium exchange mass spectrometry. Topics examined include the rationale for a reference measurement system for HDX-MS, attaining high accuracy
Houman Ghasriani, Derek Hodgson, Robert G. Brinson, Ian McEwen, Lucinda F. Buhse, Steven Kozlowski, John Marino, Yves Aubin, David Keire
The higher order structure of biotherapeutics is a critical quality attribute (CQA) that can be evaluated by nuclear magnetic resonance (NMR) spectroscopy at atomic resolution. NMR spectral "fingerprinting" can directly establish drug substance structural
Peter Bajcsy, Antonio Cardone, Joe Chalfoun, Michael W. Halter, Derek Juba, Marcin Kociolek, Michael P. Majurski, Adele P. Peskin, Carl G. Simon Jr., Mylene H. Simon, Antoine Vandecreme, Anne L. Plant, Mary C. Brady
The goal of this survey paper is to overview cellular measurements using optical microscopy imaging followed by automated image segmentation. The cellular measurements of primary interest are taken from mammalian cells and their components. They are
Jia Ma, Huaying Zhao, Julia Sandmaier, James Alexander Liddle, Peter Schuck
Sedimentation velocity (SV) analytical ultracentrifugation is a classical biophysical technique for the determination of the size-distribution of macromolecules, macromolecular complexes, and nanoparticles. SV has traditionally been carried out at a
Shuang Yang, Meiyao Wang, Lijun Chen, Illarion Turko, Karen W. Phinney, Shuwei Li
We describe the design and synthesis of a novel set of iso-baric tags for quantitative glycan profiling, which will have broad applications in carbohydrate based biomarker dis-covery, therapeutic protein characterization, and vaccine development.
Purpose: Industry and regulatory bodies desire more accurate methods for counting and characterizing particles. Measurements of proteinaceous-particle concentrations by light obscuration and flow imaging can differ by factors of ten or more. Methods: We
Methods for characterizing the higher-order structure of protein therapeutics are in great demand for establishing consistency in drug manufacturing, for detecting drug product variations resulting from modifications in the manufacturing process, and for
range from small organic and inorganic molecules to lipids, nucleic acids, peptides, and proteins. Along the protein chain making up such proteins, resident amide groups constantly exchange protons with water. When immersed in heavy water, mass
John Marino, Robert G. Brinson, Jane E. Ladner, David Travis Gallagher, Luke Arbogast, Richard Huang, Jeffrey W. Hudgens, Elyssia S. Gallagher
In contrast to small molecule therapeutics whose conformations can be absolutely defined by constitution and stereochemistry, biopharmaceuticals are distinguished by the requirement for folding into higher order structures (secondary, tertiary, and
Catherine A. Mouchahoir, Mellisa Ly, Michaella Levy, Lisa E. Kilpatrick, Scott C. Lute, Karen W. Phinney, Lisa Marzilli, Kurt A. Brorson, Michael T. Boyne, Darryl Davis, John E. Schiel
The primary sequence of a protein, including therapeutic monoclonal antibodies (mAbs), is a critical quality attribute that determines a great deal of its functionality and stability. Significant effort is devoted to determining the complete amino acid
N-linked glycosylation is a common post-translational modification that imparts structural heterogeneity to recombinant monoclonal antibody therapeutics. The various oligosaccharides attached to the CH2 domains of IgG can impact the efficacy, safety and
Protein molecules in solution can form proteinaceous particles by a variety of aggregation processes. The size and concentration of these particles is an important quality attribute for therapeutic MAb solutions. In this chapter, we describe the techniques
Wenzhou Li, James L. Kerwin, John E. Schiel, Catherine A. Mouchahoir, Darryl Davis, Andrew Mahan, Sabrina A. Benchaar
Therapeutic monoclonal antibodies (mAbs), a rapidly growing class of therapeutic drugs, present a daunting challenge for structural characterization. They are heterodimers of separate light and heavy chains comprising over 1200 amino acid residues. During
John R. Royer, George L. Burton, Daniel L. Blair, Steven D Hudson
Recent advances in colloidal synthesis make it possible to generate a wide array of precisely controlled, non-spherical, shaped particles. However, relatively little is known about the role that particle shape plays in the dynamics of colloidal suspensions
John E. Schiel, Michael T. Boyne, Sarah M. Rogstad
Monoclonal antibody therapeutics are a heterogeneous mixture of glycoforms. Multiple methods exist for defining the glycan composition and relative abundance of species present. In the current report, two MS-based methods were compared for their ability to