Caliper Life Sciences, Inc.

Dade Behring Marburg Gmbh

Behringwerke Aktiengesellschaft

Discoverx Corporation

Surromed, Inc.

Other

Siemens Healthcare Diagnostics Products Gmbh

Ark Diagnostics, Inc.

Discover, LLC

Singh, Rajendra

Ray, Sunetra

Ansaldi, Daniel

Rajendra Singh

Edwin F Ullman

Sharat Singh

Ning Zhang

Daniel Ansaldi

Frank Meneghini

Dariush Davalian

Harshvardhan Mehta

Sunetra Ray

Linda Kauffman

Tabassum Naqvi

Zhenjun Diwu

Jae Beom Kim

Johnny Jose Valdez

Byung Sook Moon

Gary Frenzel

Yun-Jung Choi

Richard M Eglen

Riaz Rouhani

Kevin P Francis

Steve De Keczer

Peter Fung

Neil Charter

Kun Peng

Halhong Zhou

Gregory Gorski

Stephen Oldfield

Jacqueline Nguyen-Choi

Disclosed herein are antibodies that specifically bind to a methotrexate analyte. Such antibodies can be used to detect a methotrexate analyte in a sample, such as in a homogeneous enzyme immunoassay method. Hapten structures to elicit such antibodies and conjugates useful in immunoassays are also described.

Antibodies to methotrexate and uses thereof

The disclosure features methods that include: administering to a subject a composition that includes particles, where each one of the particles features at least one targeting group that binds to a structural entity in the subject and at least one reacting group that reacts chemically with a reactive oxygen species in the subject, and where the particle emits luminescence when the reaction occurs; detecting the luminescence emission from the particles; and displaying an image of the subject showing locations of at least some reactive oxygen species in the subject based on the detected luminescence.

In-vivo reactive species imaging

Compositions and methods are described for normalizing a bioluminescent signal in a live animal.

Compositions and methods for in vivo evaluation of bioluminescence

Compositions and methods are described for detecting enzyme activity in a live organism (e.g., animal) are provided.

In vivo imaging of enzymatic activity

Multivalent fluorescent probes and methods of using these multivalent fluorescent probes for in vitro and in vivo imaging are described.

Multivalent fluorescent probes

Methods are disclosed for determining minute quantities of an analyte in a medium suspected of containing the analyte. One method comprises treating a medium suspected of containing an analyte under conditions such that the analyte, if present, causes a substrate having an oxidant cleavable linker and a photosensitizer to come into close proximity. The photosensitizer generates singlet oxygen which oxidatively cleaves the linker to form a product which can be detected in a sandwich detection assay such as LOCI. The amount of product detected is related to the amount of analyte in the medium. Compositions, kits, and compounds are also disclosed.

Amplified signal in binding assays

An amplifiable &#x3b2;-lactamase substrate is provided comprising an enzyme donor fragment of &#x3b2;-galactosidase linked to form a ring to a &#x3b2;-lactam ring that is a substrate for lactamase and upon opening of the &#x3b2;-lactam ring the enzyme donor fragment becomes linearized. The cyclic substrate only weakly binds to the enzyme acceptor fragment of &#x3b2;-galactosidase. The substrate finds application for the sensitive detection of &#x3b2;-lactamase for direct detection of the enzyme or when the enzyme is used as a label.

Lactamase amplification substrate

Methods and compositions are provided for determining ADP in the presence of ATP. These comprise including among the assay reagents at least one of the correcting components creatine phosphokinase and phosphocreatine, pyruvate kinase and phosphoenolpyruvate, peroxidase and a non-interfering peroxidase substrate, and catalase. One aspect of the method employs formation of hydrogen peroxide from the ADP by pyruvate kinase, phosphoenolpyruvate and pyruvate oxidase. The hydrogen peroxide is then determined. A combined reagent having all of the reagents may optionally include a peroxidase when the hydrogen peroxide is to be enzymatically determined. A peroxidase substrate is added to the sample in conjunction with the peroxidase substrate reagent, the mixture incubated and depending on whether the peroxidase substrate is a fluorescer or chemiluminescer, the mixture may be illuminated with excitation light and the emitted light determined as a measure of the ADP in the sample.

ADP detection using an enzyme-coupled reaction

A sensitive intracellular calcium assay is disclosed comprising conveniently a reagent comprised of a dye precursor capable of entering cells and being hydrolyzed to a dye, whereby the dye complexes with calcium in the cells and provides a luminescent signal, an antibody specific for the dye and conjugated with a quencher, and a cellular anion exchange enzyme inhibitor. In performing the assay, the reagent is combined with cells expressing a receptor responsive to a ligand resulting in a change in cytosolic calcium. After incubation for the dye precursor to permeate the cells, the calcium may be determined by exciting the dye precursor and determining the peak fluorescence over a time course. The method can be used for measuring the effect of an agent on cytosolic calcium by binding to a cell surface membrane receptor.

Sensitive intracellular calcium assay

Methods and reagents are provided for determining endocytosis, using a cell expressing an externally polypeptide labeled cell membrane receptor, and as a reagent an antibody to said label conjugated to a fragment of an enzyme fragment complementation pair. Compounds are tested for their effect on endocytosis by complexing the reagent with said cells, adding the test compound at any time in relation to the complexing, allowing any endocytosis to occur, proteolytically degrading external enzyme fragment, adding protease inhibitor and the complementary member of the enzyme fragment complementation pair and substrate. The product provides a detectable signal related to the amount of endocytosis that occurred. The method is readily automated as all steps can occur in a single vessel without separations and washings.

Detecting cell membrane protein endocytosis

Short enzyme donor fragments of &#x3b2;-galactosidase are provided of not more than 40 amino acids, where the short fragments are used as a label and may be substituted with a wide variety of organic compounds, particularly polypeptides having independent functional activity. The enzyme donor finds use in competitive and non-competitive assays, monitoring intracellular events, or other processes where a sensitive non-interfering label is desired.

Short enzyme donor fragment

Compounds that are modified polysaccharides having pendant aldehyde functionalities are disclosed. Each of the aldehyde functionalities is attached through a linker to a position corresponding to a hydrogen atom of a different hydroxyl group of unmodified polysaccharide. Also disclosed is a method for introducing an amine-reactive functionality into a dextran. The method comprises (a) reacting the dextran with an alkylating agent having a functionality that reacts with an hydroxyl group of the dextran thereby forming an alkylated dextran wherein the alkylating agent has an olefin group and (b) treating the alkylated dextran to convert the olefin group to an amine-reactive functionality. A polysaccharide can be conjugated to a biomolecule by carrying out the above method and reacting the amine-reactive functionality with an amine functionality on the biomolecule to produce polysaccharide conjugated to the biomolecule.

Polysaccharide conjugates of biomolecules

A liquid chromatography-electrospray ionization mass spectrometry method is capable of separating and identifying different prostaglandin isomers, including PGDand PGE. Unlike traditional gas chromatography methods, little sample preparation and no derivatization are required. The chromatography is performed under acidic conditions that are optimal for separating the isomers. A basic sheath flow liquid is added to the chromatographic eluent, resulting in high ionization efficiency when the electrospray ionization is performed in negative ion mode. Additionally, by altering the energy at which the ionization is performed, tandem mass spectra of the two isomers can be made to differ as a result of the different relative energies of the two isomers.

Mass spectrometry of prostaglandins

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San Jose, CA, United States of America

Rajendra Singh