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Cell & tissue technologies glossary & taxonomy
Evolving Terminology for Emerging Technologies
Comments? Questions? Revisions? 
Mary Chitty MSLS
Last revised January 09, 2020

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3D Cellular Models See cellular models 3D

artificial cells: Artificial cells designed for specific applications combine properties of biological systems such as nanoscale efficiency, self- organization and adaptability at relatively low cost. Individual components needed for such structures have already been developed, and now the main challenge is to integrate them in functional microscopic compartments. Andrew Pohorille, "Artificial cells, prospects for biotechnology" Trends in Biotechnology, 20 (3): 123- 128, Mar. 2002

artificial chromosomes: DNA constructs that are composed of, at least, elements such as a REPLICATION ORIGIN; TELOMERE; and CENTROMERE, that are required for successful replication, propagation to and maintenance in progeny cells. In addition, they are constructed to carry other sequences for analysis or gene transfer. MeSH, 2001  Narrower terms: Bacterial artificial chromosome BACS, Yeast Artificial Chromosomes YACS 

Bacterial artificial chromosome BAC: A vector used to clone DNA fragments (100- to 300-kb insert size; average, 150 kb) in Escherichia coli cells. Based on naturally occurring F-factor plasmid found in the bacterium E. coli. Compare cloning vector.  DOE

DNA constructs that are composed of, at least, a REPLICATION ORIGIN, for successful replication, propagation to and maintenance as an extra chromosome in bacteria. In addition, they can carry large amounts (about 200 kilobases) of other sequence for a variety of bioengineering purposes. MeSH, 2002   Related term: BAC maps. Maps, genetic & genomic

biobank: A type of biorepository that stores biological samples (usually human) for use in research Wikipedia
Coriell Institute for Biomedical Research 
Related terms: biobanking, biological specimen banks, biorepository, biospecimens, clinical biospecimens

biobanking: Leaders in BioBanking Congress 2018 Oct 14-16 Cleveland Ohio  addresses innovations in biospecimen science and infrastructure to support expanding applications. Maintaining the integrity of biospecimens allows biomedical and biopharmaceutical researchers, regulators, biorepository managers, and practitioners to investigate the best strategies for effective use of biospecimens within today’s cutting-edge biomedical research.

biological specimen banks: Facilities that collect, store, and distribute tissues, e.g., cell lines, microorganisms, blood, sperm, milk, breast tissue, for use by others. Other uses may include transplantation and comparison of diseased tissues in the identification of cancer. MeSH 1993  

biopreservation: Wikipedia 

biorepository: An organization, place, room, or container (physical entity) where biospecimens are stored. In the context of the NCI Best Practices, only biorepositories containing human specimens collected with an intention to use them for research purposes (research biorepositories) are addressed. The physical structure, policies, and the biospecimens and data contained within it are defined collectively as a biospecimen resource, defined below (NCI Best Practices working definition). BioLINC Glossary, NHLBI   

Biorepositories (or biobanks) are "libraries" where biospecimens are stored and made available for scientists to study for clinical or research purposes. These biospecimens are commonly annotated with information about the patient from whom the biospecimen was taken, including data about their medical conditions and background. There are thousands of biorepositories in the United States, which vary widely by size, the type of biospecimens collected, and purpose. Office of Biorepositories and Biospecimen Research, National Cancer Institute What are biospecimens and biorepositories? 

biospecimen: A quantity of tissue, blood, urine, or other biologically derived material. The NHLBI Biologic Specimen Repository stores human biospecimens. Portions or aliquots of a biospecimen are referred to as samples (NCI Best Practices working definition). BioLINC Glossary, NHLBI   

Materials taken from the human body, such as tissue, blood, plasma, and urine that can be used for cancer diagnosis and analysis. When patients have a biopsy, surgery, or other procedure, often a small amount of the specimen removed can be stored and used for later research. Once these samples have been properly processed and stored they are known as human biospecimens. Doctors and researchers may analyze biospecimens to look for indications of disease in the donor. Biospecimens can confirm whether a disease is present or absent in a particular patient, but they also provide other information that may be useful to the physician or a researcher. Each sample may contain DNA, proteins, and other molecules important for understanding disease progression.  Office of Biorepositories and Biospecimen Research, National Cancer Institute What are biospecimens and biorepositories? 

Biospecimens HHS FAQs Terms and Recommendations on informed consent.  The collection and use of human specimens have become essential to biomedical research.  These biospecimens include blood and other tissues, some collected originally for clinical lab tests, some removed during surgeries, and some obtained specifically for research.  While there is no accurate catalog of the number or locations of specimens, there are reasonable estimates that billions of specimens are now stored in laboratories, repositories and “tissue banks” across the country.  Coupled with associated clinical data and the power of bioinformatics, these specimens represent an invaluable resource for current and future research on human health and disease.  At the same time, there are significant ethical, legal and social policy implications relating to the collection, storage and use of biospecimens.   Includes glossary  Related terms: biobanks, biorepositories

cell assays: Assays & screening   Related term: high content screening
cell-based imaging: See Assays and Screening  high content analysis, high content screening Drug discovery & development cell-based drug discovery

cell chips:  The in vitro analysis of cell genomic activity has been revolutionized by a variety of chip technologies. Further important advances can be expected as high resolution analytical approaches are utilized to interrogate chips. [National Center for Research Resources "Integrated Genomics Technologies Workshop Report" Jan 1999] 

cell fusion: Fusion of somatic cells in vitro or in vivo, which results in somatic cell hybridization. MeSH  Broader term: fusion. Narrower term electroporation

cell microarrays: Cell assays performed on a microarray.   Related terms: tissue array, tissue biochips; Narrower term: Microarray categories frozen cell arrays

cell sorting: Wikipedia
Related terms: Molecular imaging  FACS, flow cytometry, flow sorting.

cellular engineering: A new field that addresses issues related to understanding and manipulating cell structure-function relationships. This course is intended to be a bridge between cell biologists and engineers, to understand quantitatively cell biological aspects. Cellular engineering is intrinsically connected to the new field of tissue engineering. Rice University BIOE 321Cellular Engineering course,  

cellular imaging: NIGMS supports research that will lead to a better understanding of cell structure, function and regulation at the most basic level. Such visualization at the cellular and subcellular level will lead to fundamental breakthroughs in understanding cell structure and function and how they are dynamically regulated. National Institute of General Medical Sciences, NIH

cellular models 3D: 3D Cellular Models  June 20-21, 2018 • Boston, MA Program | Inadequate representation of the human tissue environment during a preclinical screen can result in inaccurate predictions of compound effects. Thus, pharmaceutical investigators are searching for preclinical models that closely resemble original tissue for predicting clinical outcome. Three-dimensional cell culture recapitulates normal and pathological tissue architectures that provide physiologically relevant models to study normal development, disease, and drug response. However, challenges remain for screening as researchers must procure large numbers of identical 3D cell cultures, develop assays and obtain fast, automated readouts from these more complex assays.

cellular reprogramming: "made-to-order" cell lines by reprogramming cells from ill patients. These cell lines, and the techniques for producing them, offer long-sought tools for understanding -- and hopefully someday curing -- difficult-to-study diseases such as Parkinson's disease and type 1 diabetes. Science's Breakthrough of the Year: Cellular Reprogramming 2008   

Chinese Hamster Ovary CHO cells: Cell line derived from the ovary of the Chinese hamster, Cricetulus griseus. The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems  for the study of genetic alterations in cultured mammalian cells.  MeSH, 1992

chromosome microdissection:

chromosome painting: A technique for visualizing CHROMOSOME ABERRATIONS using fluorescently labeled DNA probes which are hybridized to chromosomal DNA. Multiple fluorochromes may be attached to the probes. Upon hybridization, this produces a multicolored, or painted, effect with a unique color at each site of hybridization. This technique may also be used to identify cross-species homology by labeling probes from one species for hybridization with chromosomes from another species. MeSH, 1999  Broader term: FISH

Clinical Biospecimens and Central Lab Solutions  February 20-21, 201Orlando, FL Program  The availability of high quality biological specimens, laboratory access and diagnostics services are of utmost importance for biomarker-driven clinical trials and future research. The complexity and number of samples collected during studies has increased steadily over the years and we need to come up with best practices, operational models and IT systems to deal with this volume and complexity. The next step, the testing of the samples and various laboratory services also requires significant managerial efforts whether they are outsourced or provided by an in-house laboratory. Related terms: biobanking, biorepositories

Comparative Genomic Hybridization CGH: a molecular cytogenetic method for analysing copy number variations (CNVs) relative to ploidy level in the DNA of a test sample compared to a reference sample, without the need for culturing cells. The aim of this technique is to quickly and efficiently compare two genomic DNA samples arising from two sources, which are most often closely related, because it is suspected that they contain differences in terms of either gains or losses of either whole chromosomes or subchromosomal regions (a portion of a whole chromosome). Wikipedia accessed 2018 Feb 6  Related terms: in situ hybridization

cryobiology: cryobiology:
Cryobiology: International Journal of Low Temperature Biology and Medicinepublishes research articles on all aspects of low temperature biology and medicine. Research Areas include: • Cryoprotective additives and their pharmacological actions, • Cryosurgery, • Freeze-drying,  Freezing, • Frost hardiness in plants, • Hibernation, • Hypothermia, • Medical applications of reduced temperature, • Perfusion of organs, • All pertinent methodologies Scope Note  Related terms: antifreeze proteins: Protein categories;  cryomedicine, cryotherapy: Molecular Medicine; cryoelectron tomography: Molecular Imaging; cryoelectron microscopy: Microscopy; cryogenic probe NMR & X-ray crystallography     

cryoelectron microscopy:  Electron microscopy involving rapid freezing of the samples. The imaging of frozen-hydrated molecules and organelles permits the best possible resolution closest to the living state, free of chemical fixatives or stains. MeSH, accessed Sept. 2004

Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays. MeSH 1999 [accessed prior to 2004] 

cryoelectron tomography:  A technology for taking three- dimensional pictures of a cell overcame key technical obstacles in 2002, providing insights into how the cell's machinery carries out some of the basic processes of life. "Cryoelectron tomography" works essentially like a doctor's CT scan; a computer constructs a 3-D image of a flash- frozen cell from a series of image "slices" created by penetrating electron beams.  "Science's Top 10" AAAS, 19 Dec. 2002  Related term: electron tomography

cryonics: Wikipedia

dielectrophoresis:  Can be used to separate cells. Many medical applications. Related term: electrorotation  

electron tomography: Wikipedia

electrorotation: Related term: dielectrophoresis

enucleated: Cell from which the nucleus has been removed, used for nuclear transfer to produce a cloned animal from differentiated cells. Related terms: cloning, nuclear transfer, quiescence

Because of the multidisciplinary research field, detection and isolation difficulties, and different ways of classification, there is currently no consensus about the nomenclature of cell-derived vesicles including exosomes.[1] Consequently, exosomes are also referred to as microvesicles, epididimosomes, argosomes, exosome-like vesicles, microparticles, promininosomes, prostasomes, dexosomes, texosomes, dex, tex, archeosomes and oncosomes. This confusion in terminology has led to typical exosome preparations sometimes being referred to as microvesicles and vice versa.  Wikipedia  accessed Oct 26 2017

expression microdissection: A new tissue microdissection method ... that permits array target to be efficiently prepared from cells that express a particular protein. The technique is performed using a specially designed polymer tethered to an antibody for cell targeting and to an enzyme (reverse transcriptase) for subsequent labeling of cDNA in the marked cells (or, alternatively, to a dye- generating enzyme for activation of LCM Laser Capture Microdissection] film for subsequent recovery of the targeted cells).  RF Chauaqui et. al. Nature Genetics 32 Suppl:509- 514, Dec. 2002  Related terms: layered expression scanning; Laser Capture Microdissection LCM

FACS Fluorescence Activated Cell Sorting:  also known as flow cytometry. FACS is a powerful technique for analyzing and characterizing cells that are marked with a fluorescent label (s) and is used widely in both basic research and clinical diagnostic applications. As the individual suspension cell passes through the sensing region of the FACS machine, fluorescent signals are acquired, analyzed, and stored in a computer. The size of cells as well as the expression of interested molecules (such as proteins) within a single cell can be determined. Specific cells can be further separated, sorted, and collected for further analysis.  NFCR Center for Therapeutic Antibody Engineering Glossary  Related terms: cell sorting, flow cytometry, flow sorting

flow cytometry: Technique for characterizing or separating particles such as beads or cells, usually on the basis of their relative fluorescence. IUPAC Combinatorial Chemistry

Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake. MeSH, 1982  Related terms: cell sorting, FACS, flow sorting; Labels, signaling & detection: fluorescence, dyes Narrower term: metabolic cytometry

genotype tissue expression: The Common Fund's Genotype-Tissue Expression (GTEx) program aims to study human gene expression and regulation in multiple tissues, providing valuable insights into the mechanisms of gene regulation and, in the future, its disease-related perturbations. Genetic variation between individuals will be examined for correlation with differences in gene expression level to identify regions of the genome that influence whether and how much a gene is expressed. The GTEx project includes the following initiatives: Novel Statistical Methods for Human Gene Expression Quantitative Trait Loci (eQTL) Analysis  Laboratory, Data Analysis, and Coordinating Center (LDACC) caHUB Acquisition of Normal Tissues in Support of the GTEx Project. NIH Common Fund

heterologous transplantation:  Transplantation between animals of different species. MeSH 1965  Related term: xenotransplantation

host: A cell whose metabolism is used for growth and reproduction of a virus, plasmid, or other form of foreign DNA.  IUPAC Biotech

host-vector system: A compatible combination of host (e.g. bacteria) and vector (e.g. plasmid) that allows propagation of DNA. IUPAC Biotech

human tissue engineered product: currently defined as a product that: contains or consists of engineered cells or tissues; and  is presented as having properties for, or is used in or administered to human beings with a view to regenerating, repairing or replacing a human tissue. A human tissue engineered product may contain cells or tissues of human or animal origin, or both. It may also contain additional substances, such as cellular products, biomolecules, biomaterials, chemical substances, and scaffolds or matrices that help to provide a physical support to the cells/tissues. In addition to having therapeutic applications, human tissue engineered products can have diagnostic applications where the tissue is made in vitro and is used as a platform for testing drugs and other products.  European Medical Technology Industry Association, Regenerative Medicine and Human Tissue Engineering, 2007
Broader term: tissue engineering

hybridoma: A hybrid cell line resulting from the fusion of a specific antibody- producing spleen cell (lymphocyte) with a myeloma cell, which has the growth characteristics of the myeloma component and the antibody- secreting characteristics of the lymphocyte, and will multiply to become a source of pure monoclonal antibody. IUPAC Biotech

Cells artificially created by fusion of activated lymphocytes with neoplastic cells. The resulting hybrid cells are cloned and produce pure or "monoclonal" antibodies or T-cell products, identical to those produced by the immunologically competent parent, and continually grow and divide as the neoplastic parent. MeSH, 1982

image analysis/image processing:  Assays & screening  [in context of high -content screening]

image cytometry: A technique encompassing morphometry, densitometry, neural networks, and expert systems that has numerous clinical and research applications and is particularly useful in anatomic pathology for the study of malignant lesions. The most common current application of image cytometry is for DNA analysis, followed by quantitation of immunohistochemical staining. MeSH, 1996  

an image-based study or measurement of cells. How image cytometry differs from normal microscopic studies of cells is that very large populations of cells (typically on the order of 104 to 108 cells) are imaged. To make this technically feasible on the two-photon microscope, high-speed imaging techniques are required. ... one of the main strengths of TPM is its ability to image thick tissues specimens ... An important avenue that we are also pursing is the visualization and image analysis tools necessary to study these types of datasets. A typical dataset can generate tens of gigabytes of data, far too much for a human operator to manually classify. It becomes necessary to use automated segmentation procedures to classify the cell population into various sub-populations of biological interest.  So Lab, MIT 

immortalizing oncogene  A gene that upon transfection enables a primary cell to grow indefinitely in culture. FAO glossary

immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents. MeSH, 1988

Immunohistochemistry involves using antibodies (typically visualized via an enzyme- linked antibody assay) that specifically bind to proteins of interest. This method allows one not only to assess levels of a protein but also to localize the protein within cells in the tissue sample. Related terms: Biomarkers  biomarkers Cell biology  gene localization, subcellular localization;  Gene definitions localization; Proteins protein localization
IHCWorld: Immunohistochemistry methods & techniques 

Laser Capture Microdissection LCM: Can be used to help isolate low- abundance proteins.
Laser Capture Microdissection Wikipedia   

Related terms: Expression expression microdissection, layered expression scanning, molecular profiling

laser tweezers: Laser tweezers  and related approaches are important for manipulation and isolation of subcellular organelles and structural components. National Center for Research Resources "Integrated Genomics Technologies Workshop Report" Jan 1999  Related terms: optical trapping, optical tweezers; Broader term: micromanipulation

Library of Integrated Network-Based Cellular Signatures LINCS: The basic components of biological systems – genes, proteins, metabolites and other molecules – work together in a highly orchestrated manner within cells to promote normal development and sustain health. Understanding how these interconnected components of biological pathways and networks are maintained in health, and how they become perturbed by genetic and environmental stressors and cause disease, is challenging but essential to developing new and better therapies to return perturbed networks to their normal state.  To achieve this goal, the Library of Integrated Network-based Cellular Signatures (LINCS) program aims to develop a “library” of molecular signatures, based on gene expression and other cellular changes that describe the response that different types of cells elicit when exposed to various perturbing agents, including siRNAs and small bioactive molecules. High-throughput screening approaches will be used to interrogate the cells and mathematical approaches will be used to describe the molecular changes and patterns of response. The data will be collected in a standardized, integrated, and coordinated manner to promote consistency and comparison across different cell types. LINCS NIH Common Fund 


micellar nanocontainers: Block copolymer micelles are water- soluble biocompatible nanocontainers with great potential for delivering hydrophobic drugs. An understanding of their cellular distribution is essential to achieving selective delivery of drugs at the subcellular level. R. Savic, L. Luo, A. Eisenberg, D. Maysinger, Micellar nanocontainers distribute to defined cytoplasmic organelles Science 300 (5619): 615- 618, Apr. 25, 2003  Broader term: nanocontainers

microimaging: An emerging area of scientific opportunity is the design and use of probes to study structure and function at the molecular and subcellular level in living cells. Approaches and tools such as labels that attach to specific peptide or nucleotide moieties, Fluorescent Resonance Energy Transfer, Green Fluorescent Protein (and mutant color variants), and genetically-engineered voltage or ion-sensitive fluorophores are making it possible to begin to visualize not only the distribution of molecular species in cells, but the manner in which they interact. Research and development of these, and other such technologies, hold the promise of providing scientists the capabilities to track the ebb and flow of signal transduction cascades, protein-protein interactions, protein-nucleotide interactions, movement of subcellular elements within cells, and other dynamic events. And, it appears that as such tools are elaborated and further studied, they will permit such observations to be quantitative and made in real time. Probes for Micro- Imaging the Nervous System, SBIR, 2008  

microspectrophotometry: Analytical technique for studying substances present at enzyme concentrations in single cells, in situ, by measuring light absorption. Light from a tungsten strip lamp or xenon arc dispersed by a grating monochromator illuminates the optical system of a microscope. The absorbance of light is measured (in nanometers) by comparing the difference between the image of the sample and a reference image. MeSH 1990

microtissues: Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory can now control how cells connect with one another in vitro and assemble themselves into three-dimensional, multicellular microtissues. The researchers demonstrated their method by constructing a tailor-made artificial cell-signaling system, analogous to natural cell systems that communicate via growth factors.  A new way to assemble cells into 3D microtissues, Lawrence Berkeley National Lab, 2009

microdissection: See Laser Capture Microdissection, tissue microdissection  

models biological: Theoretical representations that simulate the behavior or activity of biological processes or diseases. For disease models in living animals, DISEASE MODELS, ANIMAL is available. Biological models include the use of mathematical equations, computers, and other electronic equipment. MeSH 1973

Near InfraRed spectroscopy NIR: A noninvasive technique that uses the differential absorption properties of hemoglobin and myoglobin to evaluate tissue oxygenation and indirectly can measure regional hemodynamics and blood flow. Near- infrared light (NIR) can propagate through tissues and at particular wavelengths is differentially  absorbed by oxgenated vs. deoxygenated forms of hemoglobin and myoglobin. illumination of intact tissue with NIR allows qualitative assessment of changes in the tissue concentration of these molecules. The analysis is also used to determine body composition. MeSH, 1997

nuclear transfer: Wikipedia  See also under enucleated

optical mapping:  Uses DNA from lysed cells.

optical trapping:  Optical trapping of small particles by forces exerted by laser radiation pressure has recently been introduced into the study of biological systems. The single- beam gradient trap (optical tweezers) employs a single strongly focused laser beam. In this case, particle size is much less than and the laser light exerts a force pulling the particle toward the high focus part of the beam. Such manipulation of micron- sized (particle size larger than ) particles is also feasible. Manipulations of cells and intracellular organelles have extended to laser cutting (scissors) and to use of two- photon systems. National Center for Research Resources "Integrated Genomics Technologies Workshop Report" Jan 1999      Related/synonymous? terms: laser tweezers, optical tweezers 

optical tweezers: Developed at Bell Labs in the 1980s ... The method relies on the fact that light waves exert minute forces as well as transmitting energy. If an object is small enough -  in this case about 5 micrometers across -- it can be "trapped" or held still by a focused beam of laser light. When the laser's position changes, the trapped object moves too ... The new technique allows researchers to make measurements not possible with conventional methods and should make it easier to judge the effectiveness of inhibitors and other medicines at a variety of concentrations. "Optical tweezers measure stickiness" NIST Technology at a glance, Winter 1997    Related terms: laser tweezers; optical traps (How similar are these to optical tweezers?)  Broader term: micromanipulation

organ-on-a-chip (OOC) is a multi-channel 3-D microfluidic cell culture chip that simulates the activities, mechanics and physiological response of entire organs and organ systems, a type of artificial organ.[1] It constitutes the subject matter of significant biomedical engineering research, more precisely in bio-MEMS. The convergence of labs-on-chips (LOCs) and cell biology has permitted the study of human physiology in an organ-specific context, introducing a novel model of in vitro multicellular human organisms.  Wikipedia accessed 2018 Sept 3   Related terms: organotypic, microfluidics, microfabrication, spheroids

organotypic (biology) Describing tissue, removed from an organ, that continues to develop as it would in that organ. Wiktionary Related terms: cellular models 3d, organ on a chip,      

organotypic models:  Carcinoma cell invasion is traditionally studied in three-dimensional organotypic models composed of type I collagen and fibroblasts. However, carcinoma cell behavior is affected by the various cell types and the extracellular matrix (ECM) in the tumor microenvironment. In this study, a novel organotypic model based on human uterine leiomyoma tissue was established and characterized to create a more authentic environment for carcinoma cells. A novel organotypic model mimics the tumor microenvironment. Nurmenniemi S, Sinikumpu T, Alahuhta I, Salo S, Sutinen M, Santala M, Risteli J, Nyberg P, Salo T  Am J Pathol. 2009 Sep;175(3):1281-91. Epub 2009 Aug 13. .

patch clamping: A technique for studying the electrical currents involved in the movement of ions across cell membranes. With this technique, an electrode is affixed to the membrane so that a small patch of membrane is electrically isolated, allowing currents through it can be determined. Patch clamping is a high-resolution technique, meaning that movements through one ion channel can be recorded. Patch clamping can also involve the use of very fine pipette to measure what is going on in or on an individual cell.  

photobleaching:  Light-induced change in a chromophore, resulting in the loss of its absorption of light of a particular wave length. The photon energy causes a conformational change in the photoreceptor proteins affecting PHOTOTRANSDUCTION. This occurs naturally in the retina ( ADAPTATION, OCULAR) on long exposure to bright light. Photobleaching presents problems when occurring in PHOTODYNAMIC THERAPY, and in FLUORESCENCE MICROSCOPY. On the other hand, this phenomenon is exploited in the technique, FLUORESCENCE RECOVERY AFTER PHOTOBLEACHING, allowing measurement of the movements of proteins and LIPIDS in the CELL MEMBRANE.  MeSH 2003

Useful for determining cellular structure.

plasmid, plasmids: Extrachromosomal genetic element consisting generally of circular double- stranded DNA, which can replicate independently of chromosomal DNA.  Used as vectors for cloning DNA in bacteria or yeast host cells. IUPAC Bioinorganic 

Autonomously replicating, extrachromosomal circular DNA molecules, distinct from the normal bacterial genome and nonessential for cell survival under nonselective conditions. Some plasmids are capable of integrating into the host genome. A number of artificially constructed plasmids are used as cloning vectors. DOE

Any extrachromosomal hereditary determinant. Plasmids are self- replicating circular molecules of DNA that are found in a variety of bacterial, archaeal, fungal, algal, and plant species. MeSH, 1978  Related terms: cloning, enucleated, nuclear transfer rDNA: See recombinant DNA  

single cell analysis Assaying the products of or monitoring various biochemical processes and reactions in an individual cell. MeSH Year introduced: 2011

Single cell analysis: March 14-15, 2019 San Francisco CA Program | Accelerating Innovative Approaches to Single Cell Omics  Advanced techniques examining single cells are revolutionizing basic biology as well as our understanding of health and disease. This rapid development in isolation and analysis is showing promise and expanding applications. However, before biomarker analysis from single cells can be integrated into diagnostic and therapeutic use, hurdles including validation, interpretation, and method standardization must be addressed Innovators and early adopters present single cell omics case studies for diagnostic and therapeutic applications in genomics, transcriptomics, and proteomics

See related Molecular Diagnostics single cell in diagnostics, Ultrasensitivity single molecule

site-directed mutagenesis: The substitution or modification of a single amino acid at a defined location in a protein is performed by changing one or more base pairs in the DNA using recombinant DNA technology. IUPAC Bioinorganic

Mutagenesis where the mutation is caused by in vitro induction directed at a specific site in a DNA molecule. The most common method involves use of a chemically synthesized oligonucleotide mutant which can hybridize with the DNA target molecule. The resulting mismatch - carrying DNA duplex may then be transfected into a bacterial cell line and the mutant strands recovered. MeSH, 1991 

somatic cell hybrids: culture lines that contain the entire complement of the mouse genome and a few human chromosomes. These culture lines are developed by mixing human and mouse cells in the presence of the Sendai virus. The virus facilitates the fusing of the two cell types to form a hybrid cell. For a reason that is not entirely known, most, but not all, human chromosomes are lost from the hybrid cell

sonocytology:  Sonocytology, a recently developed technique within nanotechnology research, uses a scanning probe microscope to record the vibrational movements of cell walls and amplifies those vibrations so that humans can hear them. ...In this paper, I will address how raw cellular vibrations are converted into cellular sounds that scientists can interpret as conveying meaningful information regarding the dynamism of cellular interiors. Further, I will examine the conditions that enable scientists to describe cells as actors capable of ‘speaking’ or ‘screaming,’ and how listening to cellular sounds may eventually change how scientists think about cells—as subjects that are dynamic, environmentally situated, and experiential. SONIC EUKARYOTES: SONOCYTOLOGY, CYTOPLASMIC MILIEU AND THE TEMPS INTERIEUR 2 03 2009 SOPHIA ROOSTH  MutaMorphosis  

spheroids and 3d cell culture: It’s been well established that culturing cells in three-dimensions is much more representative of the in vivo environment than traditional two-dimensional cultures. The multicellular arrangement allows cells to interact with each other and the extracellular matrix (ECM), providing a much better understanding of cellular complexities, particular in cancer and stem cell research  Thermo Fisher, Brief History of Spheroids

synthetic biology:  The goal of synthetic biology is to make the construction of novel biological systems into a practical and useful engineering discipline. The key is the development of an engineering methodology based on standardized and well-characterized interchangeable parts. Biological systems can be a basis for practical programmable materials, providing an engineering substrate with exquisite control over and response to the chemical world. The consequences of synthetic biology will be as great as the development of chemical engineering from alchemy, with enormous and as perhaps unimaginable implications for materials science and medicine. The range of potential applications is vast, encompassing but not limited to: diagnostics, therapeutics, sensors, environmental remediation, energy production, and a host of other biomolecular and chemical manufacturing outputs. Synthetic biology can also help us gain valuable insight into fundamental biological principles and improve our quantitative understanding of the living world. Synthetic Biology Center@MIT

This exciting field is evolving so rapidly that no widely accepted definitions exist. Common to many explanations is the idea of synthetic biology as the application of engineering principles to the fundamental components of biology. … More recent advances however, have enabled scientists to make new sequences of DNA from scratch. By combining these advances with the principles of modern engineering, scientists can now use computers and laboratory chemicals to design organisms that do new things—like produce biofuels or excrete the precursors of medical drugs. To many people, this is the essence of synthetic biology.    What is synthetic biology: Defining the concept, Synthetic Biology Project

Synthetic biology: planning for a secure future, American Institute of Biological Sciences

synthetic lethal screening: Second- site mutations that are not lethal themselves, but in combination with the primary defect cause lethality. Used in yeast genetics, but can be generalized to model organisms other than yeast. The rationale is that many mutations commonly found in tumors that result in instability of the genome are loss- of- function mutations, and it is difficult to replace the function of missing or altered proteins with a small- molecule drug. The idea of screening for second- site mutations is to identify targets that when inhibited by a specific novel drug may specifically result in the death of cells that have such a loss- of- function mutation, but that will be nontoxic to normal cells. 

tissue array analysis: The simultaneous analysis of multiple samples of TISSUES or CELLS from BIOPSY or in vitro culture that have been arranged in an array format on slides or microchips. MeSH 2005 

Tissue array research program, NCI

tissue banking:  When remaining or extra tissue that has been removed during a medical procedure such as an operation, biopsy, or blood test is collected and stored. This extra tissue, not needed for your diagnosis or treatment, is used by scientists to study disease and find better ways to diagnose, prevent, and treat cancer in the future.  Dana Farber Cancer Institute  
Related terms: biobanking, biospecimens

NCI Biorepositories and Biospecimen Research Bank

tissue chips 3-D platforms designed to mimic functions of the human body and support living human tissues and cells. Referred to as "tissue chips" or "organs on chips," these devices are designed as accurate models of the structure and function of human organs, such as the lung, liver and heart. When scientists have tested the chips developed to date with compounds already known to be safe or toxic in humans, the majority have responded as predicted. Through the use of tissue chips, scientists merge technologies from complex biology with modern tissue engineering by combining miniature models of living tissues on a transparent microchip. About the size of a thumb drive, the chip designs mimic the complex biological functions of specific organs. NCATS National Center for Advancing Translational Sciences, NIH, Tissue Chip for Drug Screening   Related terms; cellular models 3D, organoids, spheroids

tissue engineering:  Generating tissue in vitro for clinical applications, such as replacing wounded tissues or impaired organs. A cell culture facility is required for cell harvest and expansion. MeSH, 2002

The term "tissue engineering" was coined at an NSF [National Science Foundation] -sponsored meeting in 1987. At a later NSF- sponsored workshop, tissue engineering was defined as "...the application of principles and methods of engineering and life sciences toward fundamental understanding ...and development of biological substitutes to restore, maintain and improve [human] tissue functions." This definition is intended to include procedures where the biological substitutes are cells or combinations of different cells that may be implanted on a scaffold such as natural collagen or as synthetic, biocompatible polymers to form a tissue. "Tissue Engineering" National Science Foundation  Narrower term: human tissue engineering Related term: Cell biology  cell patterning

tissue microarrays:  (also TMAs) consist of paraffin blocks in which up to 1000[1] separate tissue cores are assembled in array fashion to allow multiplex histological analysis. The major limitations in molecular clinical analysis of tissues include the cumbersome nature of procedures, limited availability of diagnostic reagents and limited patient sample size. The technique of tissue microarray was developed to address these issues. Multi-tissue blocks were first introduced by H. Battifora in 1986 with his so-called “multitumor (sausage) tissue block" and modified in 1990 with its improvement, "the checkerboard tissue block" . In 1998, J. Kononen and collaborators developed the current technique, which uses a novel sampling approach to produce tissues of regular size and shape that can be more densely and precisely arrayed.  Wikipedia accessed 2018 Feb 6   
Tissue Microarray Research Pro

tissue microdissection: A laboratory method that is used to procure specific cells or cell populations from a histology slide under direct microscopic visualization. The recovered cells can be studied with a variety of DNA, messenger RNA, and protein analysis methods, including new high- throughput gene expression and proteomics technologies. This approach is permitting investigators to comprehensively examine the molecular anatomy of cells in tissue sections for the first time. JW Gillespie, The role of tissue microdissection in cancer research. Cancer Journal 2001 Jan-Feb;7(1): 32- 39, Jan- Feb 2001  

tissue models:  Related term: organotypic

transfection: the process of deliberately introducing naked or purified nucleic acids into eukaryotic cells.[1][2] It may also refer to other methods and cell types, although other terms are often preferred: "transformation" is typically used to describe non-viral DNA transfer in bacteria and non-animal eukaryotic cells, including plant cells. In animal cells, transfection is the preferred term as transformation is also used to refer to progression to a cancerous state (carcinogenesis) in these cells. Transduction is often used to describe virus-mediated gene transfer into eukaryotic cells.[2][3] The meaning of the term has evolved.[4] The original meaning of transfection was "infection by transformation", i.e., introduction of genetic material, DNA or RNA, from a prokaryote-infecting virus or bacteriophage into cells, resulting in an infection. Because the term transformation had another sense in animal cell biology (a genetic change allowing long-term propagation in culture, or acquisition of properties typical of cancer cells), the term transfection acquired, for animal cells, its present meaning of a change in cell properties caused by introduction of DNA.  Wikipedia accessed 2018 Aug 18

tumoroid: Cancer

vector: 1. A DNA molecule (plasmid, virus, bacteriophage, artificial or cut DNA molecule) capable of being replicated and bearing cloning sites for the introduction of foreign DNA, used to introduce this DNA into host cells. 2. Any organism that transmits a disease between two hosts. IUPAC Biotechnology 

The two different senses of the IUPAC definitions should be clear from context.  The organisms transmitting pathogens can be insects or small animals. Vectors used in gene therapy are not pathogenic.

An agent, such as a virus or a small piece of DNA called a plasmid, that carries a modified or foreign gene. When used in gene therapy, a vector delivers the desired gene to a target cell. NHGRI 

In molecular cloning, a vector is a DNA molecule used as a vehicle to artificially carry foreign genetic material into another cell, where it can be replicated and/or expressed (e.g.- plasmid, cosmidLambda phages). A vector containing foreign DNA is termed recombinant DNA. The four major types of vectors are plasmidsviral vectorscosmids, and artificial chromosomes. Of these, the most commonly used vectors are plasmids.[1] Common to all engineered vectors are an origin of replication, a multicloning site, and a selectable marker. The vector itself is generally a DNA sequence that consists of an insert (transgene) and a larger sequence that serves as the "backbone" of the vector. The purpose of a vector which transfers genetic information to another cell is typically to isolate, multiply, or express the insert in the target cell. All vectors may be used for cloning and are therefore cloning vectors, but there are also vectors designed specially for cloning, while others may be designed specifically for other purposes, such as transcription and protein expression. Vectors designed specifically for the expression of the transgene in the target cell are called expression vectors, and generally have a promoter sequence that drives expression of the transgene. Simpler vectors called transcription vectors are only capable of being transcribed but not translated: they can be replicated in a target cell but not expressed, unlike expression vectors. Transcription vectors are used to amplify their insert. The manipulation of DNA is normally conducted on E. coli vectors, which contain elements necessary for their maintenance in E. coli. However, vectors may also have elements that allow them to be maintained in another organism such as yeast, plant or mammalian cells, and these vectors are called shuttle vectors. Such vectors have bacterial or viral elements which may be transferred to the non-bacterial host organism, however other vectors termed intragenic vectors have also been developed to avoid the transfer of any genetic material from an alien species.[2]  Insertion of a vector into the target cell is usually called transformation for bacterial cells ,[3] transfection for eukaryotic cells,[4] although insertion of a viral vector is often called transduction.[5] Wikipedia accessed 2018 Nov 8     Narrower terms: BAC Bacterial Artificial Chromosome, cloning vector, genetic vector, plasmids   

white biotechnology: Growing concerns about the dependence on imported oil, particularly in the USA, and the awareness that the world's oil supplies are not limitless are additional factors prompting the chemical and biotechnology industries to explore nature's richness in search of methods to replace petroleum-based synthetics. An entire branch of biotechnology, known as 'white biotechnology', is devoted to this. It uses living cells—from yeast, moulds, bacteria and plants—and enzymes to synthesize products that are easily degradable, require less energy and create less waste during their production. This is not a recent development:  White biotechnology  Giovanni Frazzetto  EMBO Rep. 2003 Sep; 4(9): 835–837. doi:  10.1038/sj.embor.embor928

xenograft: The transplant of an organ, tissue, or cells to an individual of another species.  NCI Cancer Dictionary

xenotransplantation:  (xenos- from the Greek meaning "foreign"), is the transplantation of living cells, tissues or organs from one species to another.[1] Such cells, tissues or organs are called xenografts or xenotransplants. It is contrasted with allotransplantation (from other individual of same species), syngeneic transplantation or isotransplantation (grafts transplanted between two genetically identical individuals of the same species) and autotransplantation (from one part of the body to another in the same person). ...It is not uncommon for patients and physicians to use the term "allograft" imprecisely to refer to either allograft (human-to-human) or xenograft (animal-to-human), but it is helpful scientifically (for those searching or reading the scientific literature) to maintain the more precise distinction in usage. Wikipedia accessed 2018 Aug 28

Xenotransplantation is any procedure that involves the transplantation, implantation or infusion into a human recipient of either (a) live cells, tissues, or organs from a nonhuman animal source, or (b) human body fluids, cells, tissues or organs that have had ex vivo contact with live nonhuman animal cells, tissues or organs. The development of xenotransplantation is, in part, driven by the fact that the demand for human organs for clinical transplantation far exceeds the supply.
 Xenotransplantation, CBER, FDA   

WHO World Health Organization, Xenotransplantation
Related term: heterologous transplantation

Yeast Artificial Chromosomes YACS: Chromosomes in which fragments of exogenous DNA ranging in length up to several hundred kilobase pairs have been cloned into yeast through ligation to vector sequences. These artificial chromosomes are used extensively in molecular biology for the construction of comprehensive genomic libraries of higher organisms. MeSH, 2002

Cell technologies resources
Cellular Glossary, Cells Alive, James Sullivan

How to look for other unfamiliar  terms

IUPAC definitions are reprinted with the permission of the International Union of Pure and Applied Chemistry.

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