Measures the physical and chemical characteristics of individual cells as they move past optical or electronic sensors; can be used to detect and characterize specific cells in a mixed population; used to determine the effects of drugs, hormones, chemicals.
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.
In medicine, the standard immunological laboratory tests to examine lymphocytes and measure cell-type ratios.
A technique for analyzing individual cells passing through a detector system. In one method, the cells are tagged with a monoclonal antibody carrying a fluorescent label. They pass through the detector at about 10,000 cells per second. Flow cytometry has many clinical and research applications. These include analysis of cell size, structure, and viability; examination of DNA and RNA in the cells; determination of pH in the cells; and chromosome analysis. Flow cytometry is also used to determine the percentages of cells in various stages of development in a population, making it possible to estimate the extent or controllability of a malignant tumor. Monitoring the number of populations of T cells, B cells, and T helper and suppressor cells and using that information to calculate the helper/suppressor ratio assist in determining the patient’s immune status. Flow cytometry has been used in monitoring survival of transplanted organs and tissues such as bone marrow.