Abstract: This invention provides methods and compositions useful for identifying and diagnosing rare fetal cells in a mixed cell population such as a maternal blood sample. The methods entail the use of specific nucleic acid probes that hybridize to fetal cell associated RNAs to identify the rare fetal cells or antibodies that bind to polypeptides encoded by the fetal cell associated RNAs for fetal cell detection. The cells detected by the methods of the present invention are useful for diagnosing the fetal cells for a genetic trait of interest, such as trisomy 21. Novel methods for simultaneous screening for fetal cells and diagnosing the fetal cells are also provided. Compositions comprising the fetal cell associated nucleic acids of the invention and their encoded proteins are also provided. The present invention further provides kits useful for practicing the present methods.

Abstract: This invention provides methods and compositions useful for identifying and diagnosing rare fetal cells in a mixed cell population such as a maternal blood sample. The methods entail the use of specific nucleic acid probes that hybridize to fetal cell associated RNAs to identify the rare fetal cells or antibodies that bind to polypeptides encoded by the fetal cell associated RNAs for fetal cell detection. The cells detected by the methods of the present invention are useful for diagnosing the fetal cells for a genetic trait of interest, such as trisomy 21. Novel methods for simultaneous screening for fetal cells and diagnosing the fetal cells are also provided. Compositions comprising the fetal cell associated nucleic acids of the invention and their encoded proteins are also provided. The present invention further provides kits useful for practicing the present methods.

Abstract: This invention provides a method for measuring an antigen concentration in a sample, which comprises: preparing VH-domain polypeptide and VL-domain polypeptide of an antibody specific to the antigen; labeling one of the polypeptides with a reporter molecule to form labeled polypeptides, and immobilizing the other polypeptide onto solid-phase to form immobilized polypeptides; contacting the antigen-containing sample and the labeled polypeptides with the solid-phase; and measuring the reporter molecule of the labeled polypeptides bound to the immobilized polypeptides. The present invention permits simpler and quicker sandwich ELISA for measurements of an antigen concentration in high sensitivity.

Abstract: This invention provides a method for measuring an antigen concentration in a sample, which comprises: preparing VH-domain polypeptide and VL-domain polypeptide of an antibody specific to the antigen; labeling one of the polypeptides with a reporter molecule to form labeled polypeptides, and immobilizing the other polypeptides onto solid-phase to form immobilized polypeptides; contacting the antigen-containing sample and the labeled polypeptides with the solid-phase; and measuring the reporter molecule of the labeled polypeptides bound to the immobilized polypeptides. The present invention permits simpler and quicker sandwich ELISA for measurements of an antigen concentration in high sensitivity.

Abstract: The storage stability of peroxidase-reactive luminescent cocktails which employ chemiluminescent 2,3-dihydro-1,4-phthalazinediones, oxidants reactant therewith to cause light emission in peroxidase-mediated luminescent reactions, and phenolic sensitivity enhancers is improved by maintaining the pH of the cocktail prior to use at a value in the range of about 3 to about 6 and preferably at a pH of about 5. An analyte sample may be subjected to a reaction resulting in a peroxidase-containing phase, the peroxidase content of which is related to the quantity of analyte in the sample, and the peroxidase phase may then be combined with the thus-described cocktail and an aqueous alkaline organic buffer to raise the pH of the resulting reaction mixture to a value in the range of 7-9, favoring light emission.

Abstract: An immunoassay is disclosed which measures the concentration of cyclosporin analytes in sample fluids. Also disclosed is radioiodinated cyclosporin having a specific activity greater than 50 ulCi/ug and fluorescent labeled cyclosporin, both of which is cross-reactive with cyclosporin analytes.