Measurement of Predictive Cancer Biomarkers by Flow Cytometry (original) (raw)

Flow cytometric analysis using digital signal processing

Cytometry, 1995

Current commercial flow cytometers employ analog circuits to produce the feature values of the pulse waveforms that result from particle analysis. The use of analog pulse processing limits the features that can be measured to pulse integral, pulse height, and pulse width, and a large amount of potentially relevant information about the shape of the pulse waveform is lost. Direct digitizing of the waveform provides a means for the extraction of additional features, for example, pulse skewness and kurtosis, as well as the Fourier properties of the pulse. Here we describe a digital pulse waveform processing system that is compatible both with a commercial flow cytometer, and with a readily available computational platform. The performance of the digital and analog systems were compared through analysis of synthetic waveforms, and the waveforms produced by standard fluorescence microspheres and biological particles. The digital waveform processing system was found to be accurate and flexible, and the value of several of its unique attributes was demonstrated using biological cells. A protocol was designed in which digital pulse processing provided a means for the quantitative monitoring of the optical alignment of the flow cytometer. It was shown that digital pulse processing could be used to discriminate between particle classes which produce feature values indistinguishable through analog pulse processing, and to discriminate accurately single cells from doublets and larger aggregates. © 1995 Wiley-Liss, Inc.

Towards in vivo flow cytometry

Journal of biophotonics, 2009

Cytometry is the characterization and measurement of cells and cellular constituents for biological, diagnostic and therapeutic purposes, embracing the fields of cell and molecular biology, biochemistry, biophysics, cell physiology, pathology, immunology, genetics, biotechnology, plant biology and microbiology. Cytometry is based on quantitative measurements of the molecular and phenotypic properties of cells using flow and image cytometry, microarrays, and proteomics. Cytomics (molecular cell systems research) aims at the understanding of the molecular architecture and functionality of cell systems (cytomes) by single-cell analysis in combination with exhaustive bioinformatic knowledge extraction. The cytomics concept has been significantly advanced by a multitude of current developments like confocal and laser scanning microscopy, multiphoton fluorescence excitation, spectral imaging, fluorescence resonance energy transfer (FRET), fast imaging in flow, optical stretching in flow, and miniaturized flow and image cytometry within laboratories on a chip or laser microdissection, as well as the use of bead arrays [1, 2]. Data sieving or data mining of the vast amounts of collected multiparameter data for exhaustive multilevel bioinformatic knowledge extraction avoids the inadvertent loss of information from unknown molecular relations being inaccessible to an a priori hypothesis. These approaches will become powerful tools for such important fields as individualized medicine, drug discovery and drug development [3-6]. This special issue is focused on state-of-the-art research in advanced cytometry and application areas with particular emphasis on novel biophotonic methods, disease diagnosis, and monitoring of disease treatment at single-cell level in stationary and flow conditions. It seeks to advance scholarly research that spans from fundamental interactions between light, cells, vascular tissue, and labeling particles, to strategies and opportunities for preclinical and clinical research. Recent advances in slide-based cytometry for in vitro application are summarized by Gerstner et al. [7]. They show that single cell based quantitation using microscope based cytometry instruments is making its way from basic research into clinical use. Calibration and quality control are essential in every cytometric analysis. Basics of standardization and

Flow Cytometry: A Blessing and a Curse

Biomedicines

Flow cytometry is a laser-based technology generating a scattered and a fluorescent light signal that enables rapid analysis of the size and granularity of a particle or single cell. In addition, it offers the opportunity to phenotypically characterize and collect the cell with the use of a variety of fluorescent reagents. These reagents include but are not limited to fluorochrome-conjugated antibodies, fluorescent expressing protein-, viability-, and DNA-binding dyes. Major developments in reagents, electronics, and software within the last 30 years have greatly expanded the ability to combine up to 50 antibodies in one single tube. However, these advances also harbor technical risks and interpretation issues in the identification of certain cell populations which will be summarized in this viewpoint article. It will further provide an overview of different potential applications of flow cytometry in research and its possibilities to be used in the clinic.

Flow Cytometry and Its Applications to Molecular Biology and Diagnosis 2.0

International Journal of Molecular Sciences

Flow cytometry is a single-cell based technology aimed to quantify the scattering of light and the emission of multiple fluorescence signals by individual cells, biological vesicles, or synthetic microscopical particles when examined one by one at high speed using lasers or other suitable illumination sources [...]