Biomaterial Database

Immunomagnetic separation and flow cytometry for rapid detection of Escherichia coli O157:H7. 1998

K H Seo, and R E Brackett, and J F Frank, and S Hilliard

Center for Food Safety and Quality Enhancement, Food Science & Technology, University of Georgia, Griffin 30223-1797, USA.

A rapid method for detecting Escherichia coli O157:H7 combining immunomagnetic beads (IMB) and flow cytometry was developed. Labeling antigens separated by IMB with fluorescent antibody enabled the detection of < 10(3) CFU bacteria per ml in pure culture. The optimum concentration of magnetic beads for flow cytometry was lower (ca. 10(5) particles per ml) than that reported for conventional IMB assay (more than 6 x 10(6) to 8 x 10(6) particles per ml). Immunomagnetic separation and flow cytometry (IMFC) were evaluated for detecting E. coli O157:H7 in the presence of a competing microorganism and for detecting antibodies in potassium phosphate buffer. The total assay time from separating antigens with IMB to analyzing with flow cytometry was about 1 h. IMFC detected 10(3) to 10(4) CFU of E. coli O157:H7 per ml in ground beef enrichment broth and could effectively discriminate between E. coli O157:H7 and competing natural flora. The new assay system provides another approach to separation and detection of low populations of pathogens and shows potential for detecting low concentrations of toxins and other soluble antigens directly from food in a short time.

UI	MeSH Term	Description	Entries
D007074	Immunoglobulin G	The major immunoglobulin isotype class in normal human serum. There are several isotype subclasses of IgG, for example, IgG1, IgG2A, and IgG2B.	Gamma Globulin, 7S,IgG,IgG Antibody,Allerglobuline,IgG(T),IgG1,IgG2,IgG2A,IgG2B,IgG3,IgG4,Immunoglobulin GT,Polyglobin,7S Gamma Globulin,Antibody, IgG,GT, Immunoglobulin
D008460	Meat	The edible portions of any animal used for food including cattle, swine, goats/sheep, poultry, fish, shellfish, and game.	Meats
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D005434	Flow Cytometry	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.	Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D006041	Goats	Any of numerous agile, hollow-horned RUMINANTS of the genus Capra, in the family Bovidae, closely related to the SHEEP.	Capra,Capras,Goat
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D018189	Immunomagnetic Separation	A cell-separation technique where magnetizable microspheres or beads are first coated with monoclonal antibody, allowed to search and bind to target cells, and are then selectively removed when passed through a magnetic field. Among other applications, the technique is commonly used to remove tumor cells from the marrow (BONE MARROW PURGING) of patients who are to undergo autologous bone marrow transplantation.	Immunomagnetic Bead Technique,Immunomagnetic Purging,Immunomagnetic Cell Separation,Bead Technique, Immunomagnetic,Bead Techniques, Immunomagnetic,Cell Separation, Immunomagnetic,Cell Separations, Immunomagnetic,Immunomagnetic Bead Techniques,Immunomagnetic Cell Separations,Immunomagnetic Purgings,Immunomagnetic Separations,Purging, Immunomagnetic,Purgings, Immunomagnetic,Separation, Immunomagnetic,Separation, Immunomagnetic Cell,Separations, Immunomagnetic,Separations, Immunomagnetic Cell
D019453	Escherichia coli O157	A verocytotoxin-producing serogroup belonging to the O subfamily of Escherichia coli which has been shown to cause severe food-borne disease. A strain from this serogroup, serotype H7, which produces SHIGA TOXINS, has been linked to human disease outbreaks resulting from contamination of foods by E. coli O157 from bovine origin.	E coli O157,E coli O157-H7,Escherichia coli O157-H7