Abstract: Novel compositions containing (i) ligand conjugated phycobiliprotein tandem dyes and (ii) unconjugated phycobiliproteins are provided wherein the phycobiliproteins are derived from the same bacterial or eukaryotic algae species. The phycobiliproteins must be the same or different, but must contain some non-crosslinked subunits which exchange. Also provided are methods for preparing these compositions, kits containing these compositions or components of the same, and methods of using these compositions for cellular and non-cellular analysis.

Abstract: Novel compositions containing (i) ligand conjugated phycobiliprotein tandem dyes and (ii) unconjugated phycobiliproteins are provided wherein the phycobiliproteins are derived from the same bacterial or eukaryotic algae species. The phycobiliproteins must be the same or different, but must contain some non-crosslinked subunits which exchange. Also provided are methods for preparing these compositions, kits containing these compositions or components of the same, and methods of using these compositions for cellular and non-cellular analysis.

Abstract: This invention relates generally to using fluorescent markers (labelled antibodies) and flow cytometry to enumerate the average number of receptors (antigen) on formed bodies (cells) in whole blood, and to evaluate the specific binding constant of the marker for the particular receptors. Mean channel fluorescence intensities of equilibrated marker-cell suspension mixtures, total concentrations of marker, and targeted cell counts obtained by established procedures are used to complete the analyses. The invention further describes a competitive binding assay between marker and unlabelled antibody for receptors shed from the surface of formed bodies into solution and receptors on the formed bodies to analyze for receptors in solution. Moreover, competitive binding assays between marker and unlabelled antibody for receptors on formed bodies in whole blood are described for determination of relative, specific, and average binding constants of unlabelled/labelled antibody for targeted receptors.

Abstract: A solid-phase immunoassay is provided for determination of HIV antigens in human physiological fluid. The immunoassay is characterized by the coating of a solid substrate with a unique monoclonal antibody which recognizes a common antigenic determinant of a group of HIV core antigens and no HIV envelope antigens of HIV. The test sample preferably also is subjected to a lysing reagent prior to the incubation for uniformly dispersing antigens which may be present in the test sample.

Abstract: A solid-phase immunoassay is provided for determination of members of an immunological pair such as antigen and/or antibody of a single binding pair in human physiological fluid, wherein a single immunoassay enables simultaneous detection of antigen and/or antibody of a single binding pair in a test sample which may have circulating antigen and/or antibody. The immunoassay is characterized by the addition of an amount of antigen or "spike" of the binding pair to the test sample prior to incubation of the test sample in the presence of a solid-phase absorbed antibody of the binding pair. The test sample preferably also is subjected to a lysing reagent prior to the incubation for uniformly dispensing antigens which may be present in the test sample.