Factor B, Human

Factor B, Human, is a single-chain glycoprotein present in normal human serum that is cleaved during the activation of complement via the alternative pathway into two fragments of 30 and 63 kDa.

Native factor B from human serum. Single-chain glycoprotein present in normal human serum at about 200 µg/ml. During activation of complement via the alternative pathway, Factor B is cleaved and thus activated by Factor D into two fragments of M.W. of 30 kDa (Ba) and 63 kDa (Bb). The Bb fragment contains the serine protease enzymatic active site. The activated Bb fragment continues activation via the alternative pathway by cleaving, and thus activating, C3 and C5.

≥1,200 Factor BH50 units/mg; ≥50% of Factor B activity in NHS (mg/mg basis)

In PBS, pH 7.2.

Following initial thaw, aliquot and freeze (-70°C).

Prepared from serum that has been shown by certified tests to be negative for HBsAg and for antibodies to HIV and HCV.

Kam, C.M., et al. 1987. J. Biol. Chem. 262, 3444.
Gotze, O. and Muller-Eberhard, H.J. 1971. J. Exp. Med. 134, 90s.

CALBIOCHEM is a registered trademark of Merck KGaA, Darmstadt, Germany

RESEARCH USE ONLY. This product is regulated in France when intended to be used for scientific purposes, including for import and export activities (Article L 1211-1 paragraph 2 of the Public Health Code). The purchaser (i.e. enduser) is required to obtain an import authorization from the France Ministry of Research referred in the Article L1245-5-1 II. of Public Health Code. By ordering this product, you are confirming that you have obtained the proper import authorization.

Toxicity: Standard Handling (A)