An immunochemical method for quantitative determination of latent antithrombin, the reactive center loop-inserted uncleaved form of antithrombin.

Summary, in English

Antithrombin (AT) is a serine protease inhibitor that has thrombin, factors IXa and Xa as target proteases. In addition to active native AT, two other forms have been identified in plasma: the reactive center loop inserted cleaved and latent, uncleaved forms. Both have been shown to be present in normal human blood. Latent AT forms a dimer with native AT in vitro, thus inactivating the native form. Here we describe a mouse monoclonal antibody, 8C8, that is specific for latent AT. The affinity of 8C8 was found to be 500-fold higher for latent than for native AT and 5000-fold higher for latent than for cleaved AT. A sandwich assay was developed to measure the concentration of latent AT in plasma, which was found to be similar to 4.8 mg L-1 in healthy individuals. The K-D of the interaction between native and latent AT was found to be 51 mu M, i.e. far above the plasma concentration of both native and latent AT, indicating a negligible complex formation in blood.

• Författare: Margareta Kjellberg; Berit Rimac; Johan Stenflo
• Avdelning/ar: Klinisk kemi, Malmö; Celiaki och diabetes
• Publiceringsår: 2007
• Språk: Engelska
• Sidor: 127-132
• Publikation/Tidskrift/Serie: Journal of Thrombosis and Haemostasis
• Volym: 5
• Länkar: http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=17059411&dopt=Abstract; http://dx.doi.org/10.1111/j.1538-7836.2006.02274.x
• Dokumenttyp: Artikel i tidskrift
• Förlag: Wiley-Blackwell
• Ämne: Cardiac and Cardiovascular Systems
• Nyckelord: latent antithrombin; immunochemical sandwich assay; antithrombin; monoclonal antibody; native-latent antithrombin dimer
• Status: Published
• Forskningsgrupp: Clinical Chemistry, Malmö; Celiac Disease and Diabetes Unit
• ISBN/ISSN/Övrigt: ISSN: 1538-7933