Anti-Complement Factor B (C3/C5 Convertase, Glycine-rich beta Glycoprotein, GBG, PBF2, Properdin Fac

Factor B is an acute-phase protein. Levels of factor B increase during inflammation. Complement factor B is a single-chain molecule of 764aa (MW of 90kD), including a leader peptide of 25aa. Factor B provides the catalytic subunit of the C3/C5 convertases of the alternative complement pathway. Assembly of the C3 convertase (C3bBb) requires binding of factor B to C3b (C3.H2O) and factor D-mediated cleavage of bound factor B resulting in the release of Ba (MW 33kD). The C3 convertase is stabilized by the binding of properdin. This provides a positive amplification loop for the classical and alternative complement pathways. Bb (MW 60kD) is the serine protease element of this convertase. After cleavage of C3, the C5 convertase ((C3b)2Bb) is formed. The Bb fragment may be regarded as a better indicator of the alternative pathway of complement activation than Ba as impaired renal filtration does directly influence Ba levels. Whereas Bb is elevated 2.2-fold in chronic renal failure (CRF) patients, plasma concentrations of Ba are 8.4-fold higher in CRF and 16-fold higher in end-stage renal disease (ESRD) patients compared to normals. Applications: Suitable for use in Western Blot, ELISA and Immunoprecipitation. Other applications not tested. Recommended Dilution: Western Blot: 1:50, Optimal dilutions to be determined by the researcher. Storage and Stability: May be stored at 4°C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20°C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.