Abstract: A method for identifying a platelet population, preferably a population of immature, reticulated platelets, in a biological sample involves incubating the biological sample for less than 5 minutes with at least one labeled, ligand (e.g., monoclonal antibody) that binds to an epitope or antigen on platelets and with a nucleic acid dye. In one embodiment, the dye is Acridine Orange and the label on the ligand is PE-Cy7. The sample is then analyzed and one or more platelet populations is rapidly identified or quantified by passing the incubated sample through a sensing region of a flow cytometer. In one embodiment, this method occurs without a washing or physical cell separation step. The incubated sample is irradiated with a laser light source, and fluorescence of the labeled ligand and the nucleic acid dye are measured along with at least one additional parameter, e.g., light scatter, direct current, axial light loss, opacity, radio frequency, and fluorescence.

Abstract: Methods for differentially identifying cells in an instrument employ compositions containing a combination of selected antibodies and fluorescent dyes having different cellular distribution patterns and specificities, as well as antibodies and fluorescent dyes characterized by overlapping emission spectra which form non-compensatable spectral patterns. When utilizing the compositions described herein consisting of fluorescent dyes and fluorochrome labeled antibodies with overlapping spectra that cannot be separated or distinguished based upon optical or electronic compensation means, a new fluorescent footprint is established. This new fluorescent footprint is a result of the overlapping spectra and the combined cellular staining patterns of the dyes and fluorochrome labeled antibodies chosen for the composition. The new fluorescent footprint results in histogram patterns that are useful for the identification of additional cell populations or subtypes in hematological disease.

Abstract: A method useful for the enumeration of cell populations in a biological sample includes the steps of reacting in a single reaction mixture a sample, a first antibody labeled with a fluorochrome having a first emission spectrum and an additional antibody. The first antibody binds to an antigenic determinant differentially expressed on leukocytes and non-leukocytes. The additional antibody binds to an antigenic determinant differentially expressed on mature and immature granulocytes or myeloid cells, and is labeled either with the first fluorochrome or an additional fluorochrome having an emission spectrum distinguishable from the first emission spectrum. The reaction mixture can be mixed with a nucleic acid dye having an emission spectrum that overlaps with one of the first or additional emission spectra. The reaction mixture may be treated with a lytic system that differentially lyses non-nucleated red blood cells and conserves leukocytes.

Abstract: A method for identifying a platelet population, preferably a population of immature, reticulated platelets, in a biological sample involves incubating the biological sample for less than minutes with at least one labeled, ligand (e.g., monoclonal antibody) that binds to an epitope or antigen on platelets and with a nucleic acid dye. In one embodiment, the dye is Acridine Orange and the label on the ligand is PE-Cy7. The sample is then analyzed and one or more platelet populations is rapidly identified or quantified by passing the incubated sample through a sensing region of a flow cytometer. In one embodiment, this method occurs without a washing or physical cell separation step. The incubated sample is irradiated with a laser light source, and fluorescence of the labeled ligand and the nucleic acid dye are measured along with at least one additional parameter, e.g., light scatter, direct current, axial light loss, opacity, radio frequency, and fluorescence.

Abstract: A blood analyzing instrument includes a single transducer for simultaneously measuring the DC volume, RF conductivity, light scattering and fluorescence characteristics of blood cells passing through a cell-interrogation zone. Preferably, the transducer includes an electro-optical flow cell which defines a cell-interrogation zone having a square transverse cross-section measuring approximately 50×50 microns, and having a length, measured in the direction of cell flow, of approximately 65 microns.

Abstract: The method of this invention is directed to the rapid preparation of a whole blood sample for photooptical analysis. In the preferred embodiments of this method, a whole blood sample, lytic reagent system and immunological stain (optional) are contacted with the sample in a common reaction vessel (i.e. cuvette or test tube), with gentle asymmetric vortex mixing, so as to maintain the particulate matter of the sample at an essentially homogeneous concentration throughout the sample. An aliquot of the contents of the reaction vessel can, thereafter, be analyzed for identification and/or quantification of the analyte of interest.

Abstract: The method of this invention is directed to the rapid preparation of a whole blood sample for photooptical analysis. In the preferred embodiments of this method, a whole blood sample, lytic reagent system and immunological stain (optional) are contacted with the sample in a common reaction vessel (i.e. cuvette or test tube), with gentle asymmetric vortex mixing, so as to maintain the particulate matter of the sample at an essentially homogeneous concentration throughout the sample. An aliquot of the contents of the reaction vessel can, thereafter, be analyzed for identification and/or quantification of the analyte of interest.