title: Rapid, direct enzyme immunoassay of 11-keto-thromboxane B2 in urine, validated by immunoaffinity/gas chromatography-mass spectrometry.
abstract: We have developed a direct enzyme immunoassay (EIA) for quantifying immunoreactive 11-keto-thromboxane B2 (iKTXB) in unprocessed human urine. Cross-reactivity with other thromboxane metabolites and prostanoids was negligible. Analytical recovery of 11-keto-TXB2 in urine specimens was 97.4% to 99.8%. Total imprecision for two clinical specimens was 8.5% and 12.2%. Intake of acetylsalicylic acid decreased the measured concentration of iKTXB. Cardiopulmonary bypass, a procedure known to activate platelets, increased the mean excretion rate of iKTXB 10-fold. Simultaneous gas chromatography-mass spectrometry analysis of 11-keto-TXB2 and 11-keto-2,3-dinor TXB2 in urine specimens (n = 17) from healthy subjects indicated that urinary iKTXB concentrations measured by EIA represented a sum of the two 11-keto metabolites. We conclude that the direct EIA is sufficiently sensitive, rapid, simple, and specific to allow screening for alterations in thromboxane biosynthesis in patients.
authors.affiliation: Novo Nordisk, Immunochemical Department, Bagsvaerd, Denmark.
authors.forename: R
authors.initials: R
authors.lastname: Djurup
authors.forename: C
authors.initials: C
authors.lastname: Chiabrando
authors.forename: A
authors.initials: A
authors.lastname: Jörres
authors.forename: R
authors.initials: R
authors.lastname: Fanelli
authors.forename: M
authors.initials: M
authors.lastname: Foegh
authors.forename: H U
authors.initials: HU
authors.lastname: Soerensen
authors.forename: P N
authors.initials: PN
authors.lastname: Joergensen
mesh_terms: D001241:Aspirin / Q000652:urine; D002315:Cardiopulmonary Bypass; D005188:False Negative Reactions; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007124:Immunoenzyme Techniques / Q000706:statistics & numerical data; D015539:Platelet Activation; D011786:Quality Control; D012680:Sensitivity and Specificity; D013929:Thromboxane B2 / Q000031:analogs & derivatives* / Q000652:urine
chemical_list: D013929:Thromboxane B2; C028965:2,3-dinor-thromboxane B2; C049235:11-dehydro-thromboxane B2; D001241:Aspirin