Complement C1s, Human, Activated, Two-Chain Form

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)

Native, human, activated C1s complement component. Present in human serum at 31 µg/ml. Nonactivated C1s is found in circulating blood plasma as a Ca²⁺-dependent dimer in association with one C1q molecule and two C1r molecules to form the first component of complement (C1). Ensuing C1q binding to classical complement pathway activators, each C1r protein is cleaved to form activated C1r enzyme. Dimeric C1r enzyme cleaves, and thus activates, each C1s molecule into two disulfide-linked fragments of M.W. 59 kDa and 28 kDa. The 28 kDa peptide contains the C1s enzymatic active site. Activated C1s continues activation via classical pathway by cleaving, and thus activating, C2 and C4.

Cooper, N.R. 1985. Adv. Immunol. 37, 151.
Sim, R.B. 1981. Methods Enzymol. 80, 6.

Please refer to vial label for lot-specific concentration.

In 130 mM NaCl, 50 mM sodium phosphate, 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.

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