Factor XIII (A-subunit) Polyclonal Antibody – Affinity Purified
Affinity’s Factor XIII (A-subunit) Polyclonal Antibody – Affinity Purified is the highest level of our Factor XIII (A-subunit) antibody family. During the Antigen Affinity Purification process the IgG has had any non-specific immunoglobulin fraction eliminated which enriches the specificity of the remaining immunoglobulin towards the target antigen. The result is a very high-purity product with a substantially higher titre than whole or purified IgG. Our Factor XIII (A-subunit) Polyclonal Antibody – Affinity Purified is provided in a solution of HEPES buffered saline containing 50% glycerol (v/v) and is intended for applications such as immunoblotting, immunostaining of cells and several types of immunoassays where the higher signal-to-noise ratio achieved with this enriched product is required.
Product Code: SAF13A-AP
Retail Product Size: 0.5mg vial
Host Animal: Sheep Anti-Human Factor XIII (A-subunit) Polyclonal Antibody – Affinity Purified
Species Cross Reactivity: View Chart
Description of Factor XIII (FXIII)
Factor XIII (FXIII, fibrin stabilizing factor) is the proenzyme form of a transamidase that is essential for normal haemostasis and fibrinolysis, wound healing, female fertility and foetal development. Extracellular F.XIII consists of A subunits (83 kDa each) which contain the enzyme moiety, and B subunits (76 kDa each) which act as a carrier protein for the A subunit in circulation. Both subunits are produced under separate genetic control. In plasma, FXIII exists as a non-covalent tetrameric complex (320 kDa) of two A-subunits and two B-subunits (A2B2). The concentration of F.XIII tetramer in plasma is ~25 μg/ml (~80 nM). An intracellular form of FXIII is found in platelets, megakaryocytes and monocytes. This form of F.XIII presents as a dimer of two A-subunits only and has a molecular weight of 160 kDa. The importance of these intracellular stores is demonstrated by the observation that platelets can contribute up to half of the FXIII activity in platelet rich plasma. The activation of FXIII involves several steps. Thrombin cleaves after Arg37 of each A-subunit in the A2B2 tetramer, releasing a 4.5 kDa activation peptide. Additional conformational changes induced by the binding of calcium, and by dissociation of the B-subunits from the A-subunit dimer are required to obtain full enzyme activity. FXIIIa is a cysteine protease that catalyses the formation of γ-glutamyl-ε-lysyl bonds between the γ and α chains of polymerised fibrin molecules. Other proteins found crosslinked into fibrin clots by FXIIIa include fibrinogen, α2antiplasmin, fibronectin, vitronectin and von Willebrand factor 1-3.
References and Review
- McDonagh J; Structure and Function of Factor XIII; in Hemostasis and Thrombosis, 3rd Edition, eds. RW Colman, J Hirsh, VJ Marder and EW Salzman, pp 301-313, J.B. Lippincott Co., Philadelphia PA, USA, 1994.
- Inbal A, Muszbek L; Coagulation Factor Deficiencies and Pregnancy Loss; Seminars in Thrombosis and Haemostasis 29, pp 171-174, 2003.
- Murdock PJ, Owens DL, Chitolie A, Hutton RA, Lee CA; Development and Evaluation of ELISAs for Factor XIIIA and XIIIB Subunits in Plasma; Thrombosis Research 67, pp 73-79, 1992.