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John T. Elliott (Fed)

Next Generation Measurement Tools for Quantitative Cellular Biology
Robust and sensitive tools for measuring a cellular response to environmental conditions are required to advance our understanding and ability to control cellular behavior. We are currently developing quantitative microscopy techniques for measuring cellular response in a variety of applications. Specific projects have involved development of novel cell stains for automated fluorescence microscopy, fixation techniques to preserve GFP within cells, fluorescence reference materials for intra-laboratory and inter-laboratory standardization of fluorescent microscopes and open source image analysis software to facilitate quantification of 3-color microscopy images.

Metrology for Tissue Engineering
Tissue engineering offers the promise of creating artificial tissues and organs that can replace diseased or damaged tissues. The success of this field relies on advances in understanding the complex set of variables governing the interaction of living cells with culture conditions and biomaterials. We currently are investigating the sensitivity and limits to quantitative evaluation of cell/biomaterial interactions with cellular assays. Our program involves the development of indicator cells that express the green fluorescent protein (GFP) under particular physiological conditions. Presently, we are using a fibroblast cell strain that expresses a GFP protein when the cell enters into a proliferation program. The natural variations in GFP expression levels among individual cells suggests that large sample populations and statistical methods will be required to evaluate the indicator cell response. We have developing several protocols for using automated fluorescent microscopy and image processing, and analysis techniques to quantify the indicator cell response. Use of these techniques with the fibroblast indicator cells described above will allow us to rapidly identify biomaterials that promote or prevent fibroblast proliferation.

Thin Films of Extracellular Matrix Proteins
Our program also involves the fabrication and characterization thin film extracellular matrix mimics. By adsorption of either native or denatured type I collagen onto alkanethiol self-assembled monolayers under various conditions, we can prepare collagen thin films that present normal or damaged collagen signals to smooth muscle cells. The fabrication technique is highly reproducible and has been characterized by atomic force microscopy, ellipsometry and fluorescent microscopy. These well-charcterized thin film extracellular matrix mimics are being used to understand how ECM mechanical properties dictate the phenotypic response from various cell types.

Development of a nanopore gas sensing platform for directly measuring nitric oxide released from cells in culture
Nitric oxide (NO) is a critical signaling molecule within mammalian cells that is involved in a variety of cellular responses including inflammation and vascular regulation. Use of NO as a biomarker for cell response has been limited by measurement difficulties related to their low abundance and limited lifetimes. We have designed and are currently building a real-time nanopore gas sensor platform that is integrated into a cell culture surface. Volatile small molecule biomarkers will be detected in the nanopore gas sensors that are directly under the cells. Methods to validate the nanopore gas sensor measurements with quantitative microscopy and cell permeable NO-reactive fluorophores are currently under development.

Quality Control Metrics for Cell Culture
Next-generation cell therapies for replacement or repair of diseased tissues will involve implantation or injection of living cells into the patient. In many cases, the living cells used in these therapies will be expanded under laboratory conditions before being used in clinical settings. We are testing cellular measurements such as spreading morphology and cell volume as quality assurance metrics for proliferating cell cultures that may be used during the production of cell therapy products.


Workshop 13: Building Measurement Assurance in Flow Cytometry

Lili Wang, Stephen Perfetto, Robert Hoffman, John T. Elliott, Sheng Lin-Gibson, Steven Bauer, Heba Degheidy, Judith Arcidiacono, Litwin Virginia
Two workshops were held to identify measurement challenges and potential solutions for building measurement assurance for flow cytometry. This report summarizes

Generating Domain Terminologies using Root- and Rule-Based Terms

Talapady N. Bhat, John T. Elliott, Ursula R. Kattner, Carelyn E. Campbell, Eswaran Subrahmanian, Ram D. Sriram, Jacob Collard, Monarch Ira
Motivated by the need for exible, intuitive, reusable, and normalized ter- minology for the semantic web, we present a general approach for generat- ing sets of

How measurement science can improve confidence in research results

Anne L. Plant, Chandler A. Becker, Robert J. Hanisch, Ronald F. Boisvert, Antonio M. Possolo, John T. Elliott
The concepts and methods of measurement science can help provide clarity in the definition of reproducibility and its role in the scientific process. The

Agglomeration of Escherichia coli with positively charged nanoparticles can lead to artifacts in a standard Caenorhabditis elegans toxicity assay

Shannon Hanna, Antonio R. Montoro Bustos, Alexander W. Peterson, Vytautas Reipa, Leona D. Scanlan, Sanem Hosbas Coskun, Tae Joon Cho, Monique E. Johnson, Vincent A. Hackley, Bryant C. Nelson, Michael R. Winchester, John T. Elliott, Elijah J. Petersen
The increased use and incorporation of engineered nanoparticles (ENPs) in consumer products requires a robust assessment of their potential environmental


Graphic with multiple blocks showing a knowledge management system

Knowledge Management System and Process for Managing Knowledge

NIST Inventors
John T. Elliott, Talapady N. Bhat, Ursula R. Kattner, Carelyn E. Campbell, Ram D. Sriram, Eswaran Subrahmanian and Jacob Collard
Patent Description This method is a general approach to generating sets of normalized terminology from a digital corpus of natural language documents in any given domain to address the need for flexible, intuitive, reusable, and normalized terminology. The terms that this approach generates are root
Created October 9, 2019, Updated June 15, 2021