Human Complement factor B Protein, Natural - 250 µg (CAT#: CB-P275-AB) Datasheet

Product Type
Factor B is an acute phase protein. The level of factor B rises during inflammation. Complement factor B is a single-chain molecule of 764 amino acids (with a molecular weight of 90 kD), including a leader peptide of 25 amino acids. Factor B provides the catalytic subunit of the C3/C5 convertase that replaces the complement pathway. The assembly of C3 convertase (C3bBb) requires the combination of factor B and C3b (C3.H2O), and factor D-mediated cleavage of the binding factor B leads to the release of Ba (MW 33 kD). C3 convertase is stabilized by the binding of properdin. This provides a positive amplification loop for the classical and alternative complement pathways. Bb (MW 60 kD) is the serine protease element of the invertase. After cutting C3, C5 convertase ((C3b)2Bb) is formed. The Bb fragment may be regarded as a better indicator of the complement activation pathway than Ba, because impaired renal filtration does directly affect Ba levels. Compared with normal people, Bb in patients with chronic renal failure (CRF) increased by 2.2 times, while the plasma concentration of Ba in CRF was 8.4 times higher, and the plasma concentration of Ba in patients with end-stage renal disease (ESRD) was 16 times higher. In addition to complement activation, factor B fragments also participate in other immune functions.
Infectious diseases, Nephrology
250 µg
PBS, pH 7.4
Functional studies
Application Notes
For functional studies, the in vitro dilution must be optimized in the user's experimental setting.
Storage Instructions
Product should be stored at -80°C. Repeated freeze and thaw cycles will cause loss of activity. Use C5 protein within 28 hours after thawing and keep on ice. Remainder amounts should be aliquoted and immediately re-freezed for future use. Aliquots should never be thawed more than once. Under recommended storage conditions, product is stable for at least one year.
Complement factor B
Alternative Names
CFB; Cfb; AI195813; AI255840; Bf; C2; Fb; H2-Bf; AHUS4; ARMD14; BFD; CFAB; CFBD; FBI12; GBG; PBF2; complement factor B

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