Abstract: The invention relates to a test system useful in carrying out diagnostic assays. One component of the test system is an unblocked solid phase test carrier with a three dimensional configuration, impregnated with a first binding partner for analyte of interest. The second component of a binding agent containing a second binding partner coupled to an immediately visually determinable label, and a blocking agent. Rapid and accurate assays may be carried out by using the described system.

Abstract: This invention relates to a method for autoclustering N-dimensional datastreams. The invention has particular utility in analyzing multi-parameter data from a flow cytometer, and more particularly has utility in analyzing data from whole blood cells tagged with fluorescently labelled CD3, CD4 and CD8 monoclonal antibodies to which a known number of fluorescent microbeads has been added.

Abstract: A method for automatic lineage assignment of acute leukemias. Eight four-parameter list mode data files are acquired with a flow cytometer in the following sequence: 1. unstained; 2. isotype controls; 3. CD10 FITC, CD19 PE; 4. CD20 FITC, CD5 PE; 5. CD3 FITC, CD22 PE; 6. CD7 FITC, CD33 PE; 7. HLADR FITC, CD13 PE and 8. CD34 FITC, CD38 PE. First, data files 3-8 are clustered employing an algorithm based on nearest neighbors. The clusters are then associated across the data files to form cell populations, using the assumption of light scatter invariance across tubes for each population. The mean positions of each cell population are compared to a decision tree which identifies normal cell populations. To identify leukemic cell populations, the algorithm eliminates normal cell populations from the data space and the remaining populations are classified as B-lineage ALL, T-lineage ALL, AML, AUL, B-CLL or unknown.

Abstract: An improved assay of target components in a sample utilizes specific gravity-altering particles which are attached to the target components by specific antibodies. The attached specific gravity-altering particles are preferably liposomes which will buoy or sink the targets to a common level in the specimen sample when the latter has been centrifuged in a transparent tube. The liposomes can provide an accentuated and more pronounced indication of the presence of the targets in the sample due to their ability to contain many multiples of fluorescent or non-fluorescent dye molecules with minimal steric interference with the attached antibodies' binding ability.

Abstract: A homogeneous immunoassay method for the simultaneous determination of one or more antibody, antigen or hapten analytes in a fluid sample, that comprises the quantification of the effect of said analytes on the statistical changes in a dimension of a light scatter pulse height distribution histogram of relatively large diameter monodisperse binding molecule-coated polymeric microspheres induced by the binding to said microspheres of polydisperse binding molecule-coated colloid metal particles of relatively small diameter. For simultaneous assays of multiple analytes, different diameter or refractive index microspheres are assigned to each analyte. The assay may be used in forward binding, displacement, inhibition, and competition type systems, with the direction of the change in histogram dimension depending on the system. A convenient dimension to measure is the normalized peak width of a graphical representation of the histogram.

Abstract: The invention provides a method of screening a substance for the ability to effect the formation of a retinoid X receptor homodimer comprising combining the substance and a solution containing retinoid X receptors and determining the presence of homodimer formation. Also provided is a method of screening a substance for an effect on a retinoid X receptor homodimer's ability to bind DNA comprising combining the substance with the homodimer and determining the effect of the compound on the homodimer's ability to bind DNA. A method of inhibiting an activity of a retinoid X receptor heterodimer comprising increasing the formation of a retinoid X receptor homodimer, thereby preventing the retinoid X receptor from forming a heterodimer and preventing the resulting heterodimer activity is also provided. A method of inhibiting an activity of a retinoid X receptor homodimer is also provided. In addition, a method of screening a response element for binding with a retinoid X receptor homodimer is provided.

Abstract: An immunoassay element for quantitatively analyzing a ligand by determining the change in enzymatic activity. When the ligand is a low molecular weight antigen, competitive reactions between the ligand, enzyme-labelled antibody and conjugate of the antigen and high molecular weight compound are utilized. When the ligand is a macromolecular antigen, a reaction between the ligand and an enzyme-labelled antibody is utilized directly. The immunoassay element comprises a substrate layer containing a non-diffusible substrate which forms a diffusible material in the presence of the enzyme, and a reagent layer for detecting the thus formed diffusible material. The non-diffusible substrate is composed of a pulverized insoluble polysaccharide. The reagent layer may further contain a fragmenting enzyme for further fragmenting the non-diffusible material.

Abstract: Procedure for the simultaneous quantification, in a single measurement, of the major types of human lymphocytes and their subsets. It includes: incubation of the sample with five different monoclonal antibodies conjugated with three different fluorochromes; measurement by flow cytometry of the three fluorescent emissions; and analysis of the results obtained by means of multiparametric analysis to determine the presence/absence of a certain fluorescence in a cell and its intensity in each cell.

Abstract: An in vitro solid-phase, competitive assay for detecting the presence of a peptide analyte in a biological sample comprises contacting a fusion protein, of first and second peptides, with a solid supported first antibody or fragment thereof, which binds the first peptide, adding a biological sample containing the peptide analyte and a second antibody or fragment thereof which binds the peptide analyte and the second peptide. The second antibody is allowed to bind any free analyte present in the sample, and to form solid supported complexes of fusion protein and antibody. The amount of solid supported second antibody detected is then compared to a control. When the amount of peptide analyte in the sample increases the amount of second antibody bound to the solid support decreases. An optional final addition of an antibody-binding molecule helps detect the solid supported complexes of the fusion protein and the second antibody or fragment.

Abstract: A method is provided to measure the extent of platelet activation by fluorometrically determining the extent of expression of P-selectin in a platelet sample in vitro, using a maximally activated platelet sample as a reference standard.

Abstract: Assay for detecting the amount or presence of target ligand in a sample. The assay includes a ligand analogue conjugate having a linkage site and a binding site, a ligand receptor, and a sample. The assay includes the steps of providing at least one crosstalk inhibitor. This inhibitor, under assay conditions, competes with the linkage site of the ligand analogue conjugate for binding to the ligand receptor, and does not compete with the binding site of the ligand analogue conjugate for binding to the ligand receptor. In the invention, the assay is performed for the target ligand in the presence of a sufficient amount of the crosstalk inhibitor to reduce the amount of binding of the linkage site of the ligand analogue conjugate to the ligand receptor. The invention also features a method for identifying crosstalk inhibitors, and the crosstalk inhibitors themselves.

Abstract: Diagnostic blood lead assays using porphobilinogen synthase protein function as an indicator of physiological response to lead exposure and as an indicator of the time period of lead exposure are disclosed.

Abstract: A specific binding assay process which is useful for quick qualitative or quantitative measurement and which can be used for various purposes, and a specific binding assay device suitable for the practice of the process,in which a substance to be assayed in a liquid test sample is determined qualitatively or quantitatively by developing the substance in a liquid test sample in a matrix, which comprises the steps of, for example:allowing the substance to be assayed to react with a specific binding substance which has specific affinity for the substance to be assayed;allowing a signal substance generator (a substance which competes with the substance to be assayed for the specific binding substance and which generates a signal) to chance its distribution in the matrix in response to the reaction of the above step, and;detecting the resulting distributional changes at a detection means as changes of signals which are rate-limited by the mass transfer of a signal substance generated from the signal substance gene

Abstract: Antibodies against highly conserved amino acid sequences of immunogenic substances, a process for the preparation of these antibodies and the use thereof in immunoassays.The invention relates to antibodies which are obtained by immunization with a peptide fragment which represents a highly conserved amino acid sequence of a native protein. The antibodies according to the invention can be used for the preparation of immunoassays, in particular for the preparation of assays for the determination of genetically engineered products such as insulin which arise as sparingly soluble inclusion bodies in microorganisms. The invention particularly relates to a multispecies insulin assay in the form of an RIA.

Abstract: An in vitro solid-phase, competitive assay for detecting the presence of a peptide analyte in a biological sample, comprising contacting a fusion protein made of a first peptide and a second peptide to a solid supported first antibody which specifically binds to the first peptide, adding thereto a biological sample containing a peptide analyte, adding a second antibody specifically binding to the analyte and the second peptide, and allowing the second antibody to bind any free analyte present in the sample and the solid supported fusion protein to form analyte-second antibody and solid supported fusion protein-second antibody complexes, and determining the amount of solid supported second antibody present and comparing it to a control. When the amount of peptide analyte in the sample increases the amount of a second antibody bound to the solid support decreases. An optional final addition of an antibody-binding molecule helps detect the antibody-fusion protein complex bound to the solid support.

Abstract: The method of detecting lower urinary tract disease is disclosed through the comparison of the concentration of a neurotrophic factor present in a urine specimen in comparison with a predetermined normal concentration. Nerve growth factor, having a concentration of approximately less than 8 picograms per milliliter is the preferred factor. The concentration of nerve growth factor in the urine rises at the onset of the lower urinary tract disease and decreases as said disease progresses. Nerve growth factor production and nerve growth is inhibited by administering the Ca.sup.++ channel blockers, verapamil or diltiazem.

Abstract: A method and means for detection of an acute myocardial infarcion (AMI) in a patient are provided. The method involves sampling of a patient's peripheral blood, quantifying the level of monocyte platelet conjugates (MP-C) and determining whether a significant increase in monocyte platelet conjugates is present. Quantification can be achieved by direct counting of monocyte platelet conjugates on a slide or under a microscope, by instrumentation measuring apparent monocyte cell volume increases, flow cytometry, or cell counter employing electrical resistance, pulse sizing or light scattering. Diagnostic test kits for detecting an AMI are also provided.

Abstract: The present application discloses a novel method for the detection of Staphylococcus aureus and methicillin-resistant strains of Staphylococcus aureus. Further disclosed is an approximately 230 kDa protein and the use of such protein in detection assays for Staphylococcus aureus and in other diagnostic applications.

Abstract: A method of determining the presence and quantity of an analyte of interest in a particulate-containing sample is disclosed, as is a construct for use in the method. The method is particularly useful for determining an analyte in whole blood and in fermentation suspensions. The construct is comprised of a first moiety, which is a particulate-binding moiety and a second moiety, which binds the analyte of interest.

Abstract: An antibody specifically immunoreactive with glycated LDL and methods for using the antibody are provided. The antibody can be used for quantitating amounts of glycated LDL in a sample, for monitoring glycemic control in diabetic patients, for diagnosing disease, for monitoring and diagnosing atherosclerotic cardiovascular disease, and for inhibiting accumulation of LDL cholesterol by cells in tissues subject to atherosclerotic disease.