Abstract: A highly sensitive assay is disclosed which combines immunomagnetic enrichment with multiparameter flow cytometric and immunocytochemical analysis to detect, enumerate and characterize carcinoma cells in the blood. The assay can detect one epithelial cell or less in 1 ml of blood and has a greater sensitivity than conventional PCR or immunohistochemistry by 1-2 orders of magnitude. In addition, the assay facilitates the biological characterization and staging of carcinoma cells.

Abstract: Devices and methods for automated collection and image analysis are disclosed that enable identification or classification of microscopic objects aligned or deposited on surfaces. Such objects, e.g. detectably labeled rare target cells, are magnetically or non-magnetically immobilized and subjected to automated laser scanning to generate sequential digitized x-y sub-images or partial images of target and non-target objects that are combined to form reconstructed full images, thereby allowing detection, enumeration, differentiation and characterization of imaged objects on the basis of size, morphology and immunophenotype.

Abstract: Methods and kits for used as an internal or external control in rare cell analysis are disclosed. A plurality of fluorescently distinct sets of cells is used to define a range to assess the isolation of rare target cells from a sample. Thus, a known number of cells, expressing the surface and intracellular antigens present in the targeted rare cells, are stabilized and modified in such a way that they can be discriminated from the targeted rare cells. In addition, these cells are separated into at least two sets based upon the number. These sets are detectably distinct from each other and provide an upper and lower indication of the detection ability of the rare cell assay.

Abstract: Separation apparatus and method for separating magnetic and/or magnetically-labeled particles from a test medium. Test medium within a reaction chamber is caused to flow past a collecting surface, and a high-gradient magnetic field is applied to the surface to capture magnetically responsive particles in the test medium. The particles are deflected toward the collection surface by baffles, a spinner, or a sprayer, or are funneled past the surface by a plunger operable to be displaced into close proximity to the surface to provide a narrow flow path for the particle-laden test medium. The particles normally suspended in the medium are separated out of suspension by adhesion to the collection surface. The particles may be resuspended by removal of the surface from the high-gradient field, or removal of the high-gradient field from the surface. The collection surface is a thin-walled non-magnetic material having a plurality of magnetic pole faces positioned therearound.

Abstract: An improved cartridge for holding a fluid sample with a small volume is disclosed herein. The cartridge has a test chamber and a vestibule through which the test fluids are inserted into the test chamber. Improved grips are flared-out to aid manipulation. The handle portion is reinforced to prevent flexing, and a prefabricated trough along the edge of the land surface prevents introduction of the adhesive into the region for analysis. The cartridge has a stopper having a dual sealing mechanism, which seals the test chamber inlet between the vestibule and the test chamber, and the mouth of the vestibule so that when the stopper is in place, the test chamber is closed to the admission of air or other contaminants. The vestibule is similarly closed against escape of the overflow from the test chamber. The stopper is composed of a single elastomer. An improved locking mechanism has two flexible walls on either side of the handhold that locks into their respective keepers on the cartridge to provide a secure lock.

Abstract: Apparatuses and methods for separating, immobilizing, and quantifying biological substances from within a fluid medium. Biological substances are observed by employing a vessel (6) having a chamber therein, the vessel comprising a transparent collection wall (5). A high internal gradient magnetic capture structure may be on the transparent collection wall (5), magnets (3) create an externally-applied force for transporting magnetically responsive material toward the transparent collection wall (5). The magnetic capture structure comprises a plurality of ferromagnetic members and has a uniform or non-uniform spacing between adjacent members. There may be electrical conductor means supported on the transparent collection wall (5) for enabling electrical manipulation of the biological substances. The chamber has one compartment or a plurality of compartments with differing heights. The chamber may include a porous wall.

Abstract: A cartridge for holding a test specimen with an extremely small volume. The cartridge has a test chamber and a vestibule through which the test fluids are inserted into the test chamber. The cartridge has a stopper having a pair of seals, the first of which seals the test chamber inlet between the vestibule and the test chamber, and the second of which seals the mouth of the vestibule so that when the stopper is in place, the test chamber is closed to the admission of air or other contaminants and the vestibule is similarly closed against escape of the overflow from the test chamber.

Abstract: Apparatuses and methods for separating, immobilizing, and quantifying biological substances from within a fluid medium. Biological substances are observed by employing a vessel (6) having a chamber therein, the vessel comprising a transparent collection wall (5). A high internal gradient magnetic capture structure may be on the transparent collection wall (5), magnets (3) create an externally-applied force for transporting magnetically responsive material toward the transparent collection wall (5). The magnetic capture structure comprises a plurality of ferromagnetic members and has a uniform or non-uniform spacing between adjacent members. There may be electrical conductor means supported on the transparent collection wall (5) for enabling electrical manipulation of the biological substances. The chamber has one compartment or a plurality of compartments with differing heights. The chamber may include a porous wall.

Abstract: Apparatuses and methods for separating, immobilizing, and quantifying biological substances from within a fluid medium. Biological substances are observed by employing a vessel having a chamber therein, the vessel comprising a transparent collection wall. A high internal gradient magnetic capture structure may be on the transparent collection wall, magnets create an externally-applied force for transporting magnetically responsive material toward the transparent collection wall. The magnetic capture structure comprises a plurality of ferromagnetic members and has a uniform or non-nonuniform spacing between adjacent members. There may be electrical conductor means supported on the transparent collection wall for enabling electrical manipulation of the biological substances. The chamber has one compartment or a plurality of compartments with differing heights. The chamber may include a porous wall.

Abstract: A highly sensitive assay is disclosed which combines immunomagnetic enrichment with multiparameter flow cytometric and immunocytochemical analysis to detect, enumerate and characterize carcinoma cells in the blood. The assay can detect one epithelial cell or less in 1 ml of blood and has a greater sensitivity than conventional PCR or immunohistochemistry by 1-2 orders of magnitude. In addition, the assay facilitates the biological characterization and staging of carcinoma cells.

Abstract: Compositions and methods are disclosed which enhance the microscopic observation and analysis of biological entities such as cells, bacteria and viruses by eliminating interfering magnetic clusters created by naturally occurring aggregators of colloidal magnetic particles. Additionally means for significantly enhancing the magnetic isolation of low antigen density target cells from biological samples are disclosed.

Abstract: Apparatus and methods are disclosed which facilitate immobilization of magnetically labelled particulate entities, e.g., cells, preferably in a defined pattern, on a collection surface via binding between specific binding pair members, as an aid to particle analysis.

Abstract: Compositions and methods are disclosed which enhance the microscopic observation and analysis of biological entities such as cells, bacteria and viruses by eliminating interfering magnetic clusters created by naturally occurring aggregators of colloidal magnetic particles. Additionally means for significantly enhancing the magnetic isolation of low antigen density target cells from biological samples are disclosed.

Abstract: Disclosed is a method that improves the efficiency of reactions between specific binding pairs. By translating one member of the pair through a suspension of the second member, or across a surface to which the second member is immobilized, collision and binding frequencies are greatly increased. The resulting increased binding frequency allows for reduced incubation times and lower incubation temperatures. The enhanced collisions are advantageous for both molecular reactions, in which mixing is not always effective, and cellular reactions, in which the cells may be damaged by mixing.

Abstract: A highly sensitive assay is disclosed which combines immunomagnetic enrichment with multiparameter flow cytometric and immunocytochemical analysis to detect, enumerate and characterize carcinoma cells in the blood. The assay can detect one epithelial cell or less in 1 ml of blood and has a greater sensitivity than conventional PCR or immunohistochemistry by 1-2 orders of magnitude. In addition, the assay facilitates the biological characterization and staging of carcinoma cells.

Abstract: Separation apparatus and method for separating magnetic and/or magnetically-labeled particles from a test medium in a reaction chamber which incorporates baffles, a spinner, a stirrer, or a plunger operable to be displaced along a collection surface to define a narrow flow path through which the particle-laden test medium must flow. The collection surface is a thin-walled non-magnetic material having a plurality of magnetic pole faces positioned therearound. Test medium within a reaction chamber is caused to flow past a collecting surface, and a high-gradient magnetic field is applied to the surface to capture magnetically responsive particles in the test medium. The particles are deflected toward the collection surface in the flow path for the test medium. The narrow flow path assures that substantially all of the particles pass within the high-gradient magnetic field along the collection surface.

Abstract: A method for transfecting and separating cells is disclosed. The method comprises preparing magnetic particles coated with genetic material and a cell-specific ligand, and using the particles to transfect target cells. The target cells may then be separated from the non-target cells by using a magnetic field.

Abstract: An apparatus for observation of magnetically labeled cells comprises an arrangement of magnets that are configured in confrontation across a horizontal gap. The magnets are further configured to produce a substantially uniform vertically-directed gradient in the gap. A sample vessel containing a fluid sample is positioned in the gap in order to allow the vertical gradient to cause collection of magnetically-labeled species on the interior upper surface of the vessel. The vessel is preferably transparent to allow observation of the collected species.