Abstract: Methods of diagnosing celiac disease in a subject are provided. In some embodiments, the method comprises contacting a sample of bodily fluid from the subject with an antigen comprising a recombinant or synthetic deamidated gliadin protein, wherein the deamidated gliadin protein comprises a hexamer of peptides each having the sequence of SEQ ID NO:1; and detecting an antibody from the sample that specifically binds to the antigen, thereby diagnosing celiac disease in the subject.

Abstract: Methods of diagnosing celiac disease in a subject are provided. In some embodiments, the method comprises contacting a sample of bodily fluid from the subject with an antigen comprising a recombinant or synthetic deamidated gliadin protein, wherein the deamidated gliadin protein comprises a hexamer of peptides each having the sequence of SEQ ID NO:1; and detecting an antibody from the sample that specifically binds to the antigen, thereby diagnosing celiac disease in the subject.

Abstract: The present invention provides a method for determining whether a subject is suffering from celiac disease by contacting a sample of bodily fluid from the subject, with an antigen formed from a hexamer of a gliadin fusion protein immobilized on a solid support. The gliadin fusion protein of the antigen includes a recombinant deamidated gliadin linked to a tag such as Glutathione-S transferase (GST) protein. The antigen is prepared by immobilizing the gliadin fusion protein on the solid support. The antigen can further include tissue Transglutaminase (tTG) cross-linked to the gliadin fusion protein. When tTG is present, the tTG and recombinant deamidated gliadin are mixed together prior to immobilization to the solid phase.

Abstract: A solid-phase immunoassay for 6-keto-Prostaglandin F1?, the stable hydrolysis product of prostacyclin (Prostaglandin I2) is disclosed. Prostacyclin, a potent vasodilator with anti-platelet and anti-proliferative properties is an effective treatment for primary pulmonary hypertension and pulmonary arterial hypertension associated with scleroderma and scleroderma-like syndrome. Levels of 6-keto-Prostaglandin F1? can be directly correlated with levels of prostacyclin. Therefore, 6-keto-Prostaglandin F1? has become the indicator of choice to measure prostacyclin levels. The single step immunoassay for 6-keto-Prostaglandin F1? uses the bioluminescent protein, aequorin as a label. Analyte-label conjugates were constructed by linking the carboxyl group of 6-keto-Prostaglandin F1? and lysine residues of aequorin by chemical conjugation methods. The binding properties of 6-keto-Prostaglandin F1? towards its antibody and the bioluminescent properties of aequorin are retained in the conjugate.