Analysis of a marine sample of photosynthetic picoplankton by flow cytometry showing three different populations (Prochlorococcus, Synechococcus and picoeukaryotes)

Flow cytometry is a technique for counting, examining and sorting microscopic particles suspended in a stream of fluid. It allows simultaneous multiparametric analysis of the physical and/or chemical characteristics of single cells flowing through an optical and/or electronic detection apparatus. Image File history File links Picoplancton_cytometrie. ... Image File history File links Picoplancton_cytometrie. ... The leaf is the primary site of photosynthesis in plants. ... Picoplankton is the fraction of plankton composed by cells between 0. ... Prochlorococcus is a genus of marine cyanobacteria that now includes some three dozen species, differentiated on the basis of their ribosomal DNA. Sallie W. Chisholm of the Massachusetts Institute of Technology, Robert J. Olson of the Woods Hole Oceanographic Institution, and other collaborators (according to the Scientific American article listed... Species Skuja Fjerdingstad Skuja Rabenhorst Okada A. E. Bailey-Watts & J. Komárek Norris (Nägeli) Nägeli F. Hindák F. Hindák Wawrik Gardner Yoneda Copeland Jao Negoro Skuja (Pringsheim) Komárek Dor Komárek & Anagnostidis Grunow G.S. West Komárek Frémy Skuja (Moore & Carter) Kom... It has been suggested that this article or section be merged into parametric statistics. ... Antonym of psychical. ... A chemical substance is any material substance used in or obtained by a process in chemistry: A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions. ... See also list of optical topics. ...

Principle

A beam of light (usually laser light) of a single wavelength is directed onto a hydro-dynamically focused stream of fluid. A number of detectors are aimed at the point where the stream passes through the light beam; one in line with the light beam (Forward Scatter or FSC) and several perpendicular to it (Side Scatter (SSC) and one or more fluorescent detectors). Each suspended particle passing through the beam scatters the light in some way, and fluorescent chemicals found in the particle or attached to the particle may be excited into emitting light at a lower frequency than the light source. This combination of scattered and fluorescent light is picked up by the detectors, and by analysing fluctuations in brightness at each detector (one for each fluorescent emission peak) it is then possible to extrapolate various types of information about the physical and chemical structure of each individual particle. FSC correlates with the cell volume and SSC depends on the inner complexity of the particle (i.e. shape of the nucleus, the amount and type of cytoplasmic granules or the membrane roughness). Some flow cytometers on the market have eliminated the need for fluorescence and use only light scatter for measurement. Other flow cytometers form images of each cell's fluorescence, scattered light, and transmitted light. This article does not cite any references or sources. ... Experiment with a laser (likely an argon type) (US Military) In physics, a laser is a device that emits light through a specific mechanism for which the term laser is an acronym: light amplification by stimulated emission of radiation. ... For further information for Hydrodynamic focusing visit the link:http://www. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. ... Scattering is a general physical process whereby some forms of radiation, such as light, sound or moving particles, for example, are forced to deviate from a straight trajectory by one or more localized non-uniformities in the medium through which it passes. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. ... In fluorescence spectroscopy an emission spectrum is a fluorescence spectrum that illustrates fluorescence evoked over a range of wavelengths when the incident light wavelength is constant. ... Drawing of the structure of cork as it appeared under the microscope to Robert Hooke from Micrographia which is the origin of the word cell. Cells in culture, stained for keratin (red) and DNA (green). ... Look up nucleus in Wiktionary, the free dictionary. ... It has been suggested that Cytoplast be merged into this article or section. ... The cell membrane (also called the plasma membrane, plasmalemma or phospholipid bilayer) is a semipermeable lipid bilayer common to all living cells. ...

Flow cytometers

Modern flow cytometers are able to analyse several thousand particles every second, in "real time", and can actively separate and isolate particles having specified properties. A flow cytometer is similar to a microscope, except that instead of producing an image of the cell, flow cytometry offers "high-throughput" (for a large number of cells) automated quantification of set parameters. To analyze solid tissues single-cell suspension must first be prepared. Robert Hookes microscope (1665) - an engineered device used to study living systems. ... In language and logic, quantification is a construct that specifies the extent of validity of a predicate, that is the extent to which a predicate holds over a range of things. ... Biological tissue is a collection of interconnected cells that perform a similar function within an organism. ...

A flow cytometer has 5 main components:

• a flow cell - liquid stream (sheath fluid) carries and aligns the cells so that they pass single file through the light beam for sensing.
• a light source - commonly used are lamps (mercury, xenon); high power water-cooled lasers (argon, krypton, dye laser); low power air-cooled lasers (argon (488nm), red-HeNe (633nm), green-HeNe, HeCd (UV)); diode lasers (blue, green, red, violet).
• a detector and Analogue to Digital Conversion (ADC) system - generating FSC and SSC as well as fluorescence signals.
• an amplification system - linear or logarithmic.
• a computer for analysis of the signals.

Early flow cytometers were generally experimental devices, but recent technological advances have created a considerable market for the instrumentation, as well as the reagents used in analysis, such as fluorescently-labeled antibodies and analysis software. General Name, Symbol, Number mercury, Hg, 80 Chemical series transition metals Group, Period, Block 12, 6, d Appearance silvery Standard atomic weight 200. ... General Name, Symbol, Number xenon, Xe, 54 Chemical series noble gases Group, Period, Block 18, 5, p Appearance colorless Standard atomic weight 131. ... Krypton laser is an ion laser, a type of gas laser using krypton ions as a gain medium, pumped by electric discharge. ... Krypton laser is an ion laser, a type of gas laser using krypton ions as a gain medium, pumped by electric discharge. ... A laser diode is a laser where the active medium is a semiconductor p-n junction similar to that found in a light-emitting diode. ... The word linear comes from the Latin word linearis, which means created by lines. ... In mathematics, if two variables of bn = x are known, the third can be found. ... Fluorescent labeling is the process of covalently attaching a fluorophore to another molecule, such as a protein or nucleic acid. ...

Modern instruments usually have multiple lasers and fluorescence detectors (the current record for a commercial instrument is 4 lasers and 18 fluorescence detectors). Increasing the number of lasers and detectors allows for multiple antibody labelling, and can more precisely identify a target population by their phenotype. Certain instruments can even take digital images of individual cells, allowing for the analysis of fluorescent signal location within or on the surface of cells. Individuals in the mollusk species Donax variabilis show diverse coloration and patterning in their phenotypes. ...

The data generated by flow-cytometers can be plotted in a single dimension, to produce a histogram, or in two dimensional dot plots or even in three dimensions. The regions on these plots can be sequentially separated, based on fluorescence intensity, by creating a series of subset extractions, termed "gates". Specific gating protocols exist for diagnostic and clinical purposes especially in relation to haematology. The plots are often made on logarithmic scales. Because different fluorescent dyes' emission spectra overlap [1], signals at the detectors have to be compensated electronically as well as computationally. 2-dimensional renderings (ie. ... Example of a histogram of 100 normally distributed random values. ... In physics, intensity is a measure of the time-averaged energy flux. ... Hematology is the branch of medicine that is concerned with blood and its disorders. ...

Fluorescence-activated cell-sorting

Fluorescence-activated cell-sorting (FACS) is a specialised type of flow cytometry. It provides a method for sorting a heterogenous mixture of biological cells into two or more containers, one cell at a time, based upon the specific light scattering and fluorescent characteristics of each cell. It is a useful scientific instrument as it provides fast, objective and quantitative recording of fluorescent signals from individual cells as well as physical separation of cells of particular interest. The acronym FACS is trademarked and owned by Becton Dickinson^[1] although it is used within the scientific community as a general term. The first cell sorter was invented by Mack Fulwyler in 1965 using the principle of Coulter volume, a relatively difficult technique to use for sorting. The technique was expanded by Len Herzenberg who was responsible for the term FACS. Herzenberg won the Kyoto Prize in 2006 for his work in flow cytometry. Cells in culture, stained for keratin The cell is the structural and functional unit of all living organisms. ... Scattering is a general physical process whereby some forms of radiation, such as light, sound or moving particles, for example, are forced to deviate from a straight trajectory by one or more localized non-uniformities in the medium through which it passes. ... Fluorescence induced by exposure to ultraviolet light in vials containing various sized cadmium selenide (CdSe) quantum dots. ... A trademark or trade mark[1] is a distinctive sign of some kind which is used by an individual, business organization or other legal entity to uniquely identify the source of its products and/or services to consumers, and to distinguish its products or services from those of other entities. ... BD (NYSE: BDX) — originally, Becton & Dickinson — is a leading global medical technology company that manufactures and sells medical devices, instrument systems and reagents. ... A genericized trademark, generic trade mark, generic descriptor, or proprietary eponym, is a trademark or brand name which has become the colloquial or generic description for a particular class of product or service. ... Leonard Arthur Herzenberg (born 5 November 1931) is an immunologist, geneticist and professor at Stanford University. ... The Kyoto Prize (京都賞) has been awarded annually since 1984 by the Inamori Foundation, founded by Kazuo Inamori (fortune from ceramics). ...

The cell suspension is entrained in the center of a narrow, rapidly flowing stream of liquid. The flow is arranged so that there is a large separation between cells relative to their diameter. A vibrating mechanism causes the stream of cells to break into individual droplets. The system is adjusted so that there is a low probability of more than one cell being in a droplet. Just before the stream breaks into droplets the flow passes through a fluorescence measuring station where the fluorescent character of interest of each cell is measured. An electrical charging ring is placed just at the point where the stream breaks into droplets. A charge is placed on the ring based on the immediately prior fluorescence intensity measurement and the opposite charge is trapped on the droplet as it breaks from the stream. The charged droplets then fall through an electrostatic deflection system that diverts droplets into containers based upon their charge. In some systems the charge is applied directly to the stream and the droplet breaking off retains charge of the same sign as the stream. The stream is then returned to neutral after the droplet breaks off. A liquid will usually assume the shape of its container A liquid is one of the main states of matter. ... DIAMETER is an AAA protocol (Authentication, Authorization and Accounting) succeeding its predecessor RADIUS. // The name is a pun on the RADIUS protocol, which is the predecessor (a diameter is twice the radius). ... Oscillation is the variation, typically in time, of some measure as seen, for example, in a swinging pendulum. ... Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interaction. ... Electrostatic deflection refers to a technique for modifying the path of a stream of charged particles by the use of an electric field applied transverse to the path of the particles. ...

Fluorescent labels

The fluorescence labels that can be used, will depend on the lamp or laser used to excite the fluorochromes and on the detectors available:^[2]

blue argon laser (488 nm)

This is an air cooled laser and therefore cheaper to set up and run. It is the most commonly available laser on single laser machines.

• Green (usually labelled FL1): FITC, GFP, CFSE, CFDA-SE
• Orange (usually FL2): PE
• Red channel (FL3): PerCP, PE-Cy5, PE-Cy5.5, PI
• Infra-red (FL4): PE-Cy7

UV helium-cadmium (HeCd) laser (325 nm)

• Ultraviolet: Hydroxycoumarin
• Blue: Y66H, Hoechst 33342, Hoechst 33342
• Green: Y66F

UV (HBO) lamp (366 nm) (usually used for DNA work)

• Violet: Indo-1
• Blue: DAPI, Hoechst 33342, Hoechst 33342, AMCA
• Blue-green: MBB

violet diode laser (405 nm)

• Pacific Blue® (manufactured by BD)
• AmCyan

green helium-neon (HeNe) laser (543nm)

Seldom used because the colour is too close to the 488nm blue laser that most machines use. Fluorescein in dropper used for eye examination. ... It has been suggested that mGFP be merged into this article or section. ... CFSE (Carboxyfluorescein succinimidyl ester) is a fluorescent cell staining dye. ... CFDA-SE (Carboxyfluorescein diacetate, succinimidyl ester) is a cell permeable dye generally used in animal cell proliferation research. ... Phycoerythrin is a red protein from the light-harvesting phycobiliproteins family, isolated from red, blue-green, and crytomonad algae. ... Propidium iodide (or PI) is a fluorescent biomolecule that can be used to stain DNA. PI also binds to RNA, necessitating treatment with nucleases to distinguish between RNA and DNA staining (1). ... “UV” redirects here. ... Transmission image of HeLa cells, with overlay of Hoechst 33258 staining (blue). ... Transmission image of HeLa cells, with overlay of Hoechst 33258 staining (blue). ... “UV” redirects here. ... A mercury-vapor yard light approximately 15 seconds after starting A Mercury-vapor lamp is a gas discharge lamp which uses mercury in an excited state to produce light. ... Structural formula of DAPI DAPI or 4,6-diamidino-2-phenylindole is a fluorescent stain that binds strongly to DNA. It is used extensively in fluorescence microscopy. ... Transmission image of HeLa cells, with overlay of Hoechst 33258 staining (blue). ... Transmission image of HeLa cells, with overlay of Hoechst 33258 staining (blue). ... The Air Movement and Control Association International, Inc. ... Messerschmitt is a famous German aircraft manufacturer, known primarily for their World War II fighter aircraft, notably the Bf 109 and Me 262. ... BD (NYSE: BDX) — originally, Becton & Dickinson — is a leading global medical technology company that manufactures and sells medical devices, instrument systems and reagents. ...

red helium-neon (HeNe) laser (633 nm) or red diode laser (635 nm)

• APC
• APC-Cy7
• Cy5

Allophycocyanin is an accessory pigment to bacteriochlorophyll and is part of the phycobilin accessory pigment family, along with phycocyanin and phycoerythrin. ... Cyanine is a non-systematic name of a synthetic dye family with the common molecular formula: ArN+=CH[CH=CH]n=NAr where two quaternized nitrogens are joined by a poly-methine chain[1]. Both nitrogens are each independently part of a heteroaromatic moiety, such as imidazole, pyridine, pyrrole, quinoline...

Measurable parameters

This list is very long and constantly expanding.

• volume and morphological complexity of cells
• cell pigments such as chlorophyll or phycoerythrin
• DNA (cell cycle analysis, cell kinetics, proliferation etc.)
• RNA
• chromosome analysis and sorting (library construction, chromosome paint)
• protein expression and localization
• transgenic products in vivo, particularly the Green fluorescent protein or related fluorescent proteins
• cell surface antigens (Cluster of differentiation (CD) markers)
• intracellular antigens (various cytokines, secondary mediators etc.)
• nuclear antigens
• enzymatic activity
• pH, intracellular ionized calcium, magnesium, membrane potential
• membrane fluidity
• apoptosis (quantification, measurement of DNA degradation, mitochondrial membrane potential, permeability changes, caspase activity)
• cell viability
• monitoring electropermeabilization of cells
• oxidative burst
• characterising multidrug resistance (MDR) in cancer cells
• glutathione
• various combinations (DNA/surface antigens etc.)

Morphology is the following: In linguistics, morphology is the study of the structure of word forms. ... Natural Ultramarine pigment in powdered form. ... The different chlorophyll and non-chlorophyll pigments associated with the photosystems all have different spectra, either because the spectra of the different chlorophyll pigments are modified by their local protein environment, or because the accessory pigments have intrinsically different absorption spectra from chlorophyll. ... Phycoerythrin is a red protein from the light-harvesting phycobiliproteins family, isolated from red, blue-green, and crytomonad algae. ... The structure of part of a DNA double helix Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions for the development and function of living organisms. ... The cell cycle, or cell-division cycle, is the series of events that take place in an eukaryotic cell between its formation and the moment it replicates itself. ... Kinetic energy (also called vis viva, or living force) is energy possessed by a body by virtue of its motion. ... The word proliferation can refer to: Nuclear proliferation Chemical weapon proliferation the spread in use of other weapons systems Cell proliferation According to Gloria Anzaldúa (1990), the difference between appropriation and proliferation is that the first steals and harms; the second helps heal breaches of knowledge. ... Ribonucleic acid (RNA) is a nucleic acid polymer consisting of nucleotide monomers, that acts as a messenger between DNA and ribosomes, and that is also responsible for making proteins out of amino acids. ... Figure 1: A representation of a condensed eukaryotic chromosome, as seen during cell division. ... A representation of the 3D structure of myoglobin, showing coloured alpha helices. ... It has been suggested that mGFP be merged into this article or section. ... An antigen is a molecule that stimulates an immune response. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ... In cell biology, molecular biology and related fields, the word intracellular means inside the cell. It is used in contrast to extracellular (outside the cell). ... Cytokines are a group of proteins and peptides that are used in organisms as signaling compounds. ... An antigen is a molecule that stimulates an immune response. ... Ribbon diagram of the enzyme TIM, surrounded by the space-filling model of the protein. ... The correct title of this article is . ... ... General Name, Symbol, Number calcium, Ca, 20 Chemical series alkaline earth metals Group, Period, Block 2, 4, s Appearance silvery white Standard atomic weight 40. ... General Name, Symbol, Number magnesium, Mg, 12 Chemical series alkaline earth metals Group, Period, Block 2, 3, s Appearance silvery white solid at room temp Standard atomic weight 24. ... This article or section is in need of attention from an expert on the subject. ... Viscosity is a measure of the resistance of a fluid to deformation under shear stress. ... A section of mouse liver showing an apoptotic cell indicated by an arrow // Apoptosis is a process of deliberate life relinquishment by a cell in a multicellular organism. ... Caspases are a group of cysteine proteases, enzymes with a crucial cysteine residue that can cleave other proteins after an aspartic acid residue, a specificity which is unusual among proteases. ... Viability can mean: In an environmental conservation context, viability indicates the ability of a conservation target to persist for many generations or over long time periods. ... Respiratory burst is the rapid release of reactive oxygen species (superoxide radical and hydrogen peroxide) from different types of cells. ... Multidrug resistance is the ability of pathologic cells to withstand chemicals that are designed to aid in the eradication of such cells. ... Glutathione (GSH) is a tripeptide. ...

Applications

The technology has applications in a number of fields, including molecular biology, pathology, immunology, plant biology and marine biology. In the field of molecular biology it is especially useful when used with fluorescence tagged antibodies. These specific antibodies bind to antigens on the target cells and help to give information on specific characteristics of the cells being studied in the cytometer. It has broad application in medicine (especially in transplantation, hematology, tumor immunology and chemotherapy, genetics and sperm sorting in IVF). In marine biology, the auto-fluorescent properties of photosynthetic plankton can be exploited by flow cytometry in order to characterise abundance and community structure. In protein engineering, flow cytometry is used in conjunction with yeast display and bacterial display to identify cell surface-displayed protein variants with desired properties. Molecular biology is the study of biology at a molecular level. ... Pathology (from Greek pathos, feeling, pain, suffering; and logos, study of; see also -ology) is the study of the processes underlying disease and other forms of illness, harmful abnormality, or dysfunction. ... Immunology is a broad branch of biomedical science that covers the study of all aspects of the immune system in all organisms. ... Botany is the scientific study of plant life. ... Marine biology is the scientific study of the plants, animals and other organisms that live in the ocean or any other body of water. ... An antigen is a molecule that stimulates an immune response. ... medicines, see medication and pharmacology. ... Photomontage of plankton organisms Plankton are any drifting organism that inhabits the water column of oceans, seas, and bodies of fresh water. ... Yeast display (or yeast surface display) is a technique used in the field of protein engineering. ... Bacterial Display (or bacteria display or bacterial surface display) is a protein engineering technique used for in vitro protein evolution. ...

See also

• Fluorescence microscopy

Microscopy is any technique for producing visible images of structures or details too small to otherwise be seen by the human eye. ...

External links

• MeSH Flow+cytometry

Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ...

Resources

• How a flow cytometer operates
• Table of fluorochromes
• Useful Java applet from BD bioscience allows visualization of absorbance and emission of different flourophores, useful for planning multi-color flow cytometry

Laboratories

• Cardiff University Introduction to Flow Cytometry
• Bender MedSystems FlowCytomix

Books

• Flow Cytometry First Principles by Alice Longobardiɰ Givan
• Practical Flow Cytometry by Howard M. Shapiro

λΔœýŤЕÞì Pathology (from Greek pathos, feeling, pain, suffering; and logos, study of; see also -ology) is the study of the processes underlying disease and other forms of illness, harmful abnormality, or dysfunction. ... The term disease refers to an abnormal condition of an organism that impairs function. ... Necrosis (in Greek Νεκρός = Death) is the name given to accidental death of cells and living tissue. ... An infection is the detrimental colonization of a host organism by a foreign species. ... In medicine, ischemia (Greek ισχαιμία, isch- is restriction, hema or haema is blood) is a restriction in blood supply, generally due to factors in the blood vessels, with resultant damage or dysfunction of tissue. ... An abscess on the skin, showing the redness and swelling characteristic of inflammation. ... Wound healing, or wound repair, is the bodys natural process of regenerating dermal and epidermal tissue. ... Neoplasia (new growth in Greek) is abnormal proliferation of cells in a tissue or organ. ... Anatomic pathology is a medical specialty (a branch of pathology) that is concerned with the diagnosis of disease based on the gross, microscopic, and molecular examination of cells and tissues. ... Anatomic pathology is a medical specialty (a branch of pathology) that is concerned with the diagnosis of disease based on the gross, microscopic, and molecular examination of cells and tissues. ... Cytopathology is a branch of pathology that studies and diagnoses diseases on the cellular level. ... Post-mortem, postmortem and post mortem redirect here. ... Molecular pathology is an emerging discipline within anatomic pathology which is focused on the use of nucleic acid-based techniques such as DNA sequencing, fluorescent in-situ hybridization, reverse-transcriptase polymerase chain reaction, and nucleic acid microarrays for specialised studies of disease in tissues and cells. ... Forensic pathology, first recognized in the USA by the American Board of Pathology in 1959, is a branch of medicine concerned with determining cause of death usually for civil or criminal law cases. ... Dental pathologists are doctors of dental science who specialise in the diagnosis and characterization of diseases of the teeth, jaw, and maxilla through the examination of tissue specimens. ... Gross examination or grossing is the process by which pathology specimens are inspected with the naked eye to obtain diagnostic information, while being processed for further microscopic examination. ... Histopathology is a field of pathology which specialises in the histologic study of diseased tissue. ... Immunohistochemistry or IHC refers to the process of localizing proteins in cells of a tissue section exploiting the principle of antibodies binding specifically to antigens in biological tissues. ... The electron microscope is a microscope that can magnify very small details with high resolving power due to the use of electrons rather than light to scatter off material, magnifying at levels up to 500,000 times. ... Immunofluorescence is the labeling of antibodies or antigens with fluorescent dyes. ... A metaphase cell positive for the bcr/abl rearrangement using FISH. The chromosomes can be seen in blue. ... Clinical Pathology is one of the two major divisions of Pathology. ... Clinical chemistry (also known as clinical biochemistry, chemical pathology or pure blood chemistry) is the area of pathology that is generally concerned with analysis of bodily fluids. ... Hematopathology is the branch of pathology which studies diseases of hematopoietic cells (see below). ... Transfusion medicine (or transfusiology) is the branch of medicine that is concerned with the transfusion of blood and blood components. ... Medical microbiology is a branch of microbiology which deals with the study of microorganisms including bacteria, viruses, fungi and parasites which are of medical importance and are capable of causing diseases in human beings. ... The specificity of the bond between antibody and antigen has made it an excellent tool in the detection of substances in a variety of diagnostic techniques, known collectively as diagnostic immunology. ... Enzyme assays are laboratory methods for measuring enzymatic activity. ... Mass spectrometry (also known as mass spectroscopy (deprecated)[1] or informally, mass-spec and MS) is an analytical technique used to measure the mass-to-charge ratio of ions. ... Pictured is a sophisticated gas chromatography system. ... A blood bank is a cache or bank of blood or blood components, gathered as a result of blood donation, stored and preserved for later use in blood transfusions. ... A microbiological culture is a way to determine the cause of infectious disease by letting the agent multiply (reproduce) in predetermined media. ... Serology is literally the scientific study of the blood serum. ...