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. 1986 Jan 15;233(2):559–564. doi: 10.1042/bj2330559

Characteristics of complement subcomponents C1r and C1s synthesized by Hep G2 cells.

A Reboul, J C Bensa, M G Colomb
PMCID: PMC1153062  PMID: 3006672

Abstract

The association and activation states of complement subcomponents C1r and C1s biosynthesized by Hep G2 cells were studied. C1r and C1s are secreted in stoichiometric amounts; in the presence of Ca2+ they are associated in a complex that sediments similarly to plasma C1r2-C1s2. Both compounds are synthesized as monomer proteins of apparent Mr 86 000. C1r is secreted as a dimer. Secreted C1r is not autoactivatable but undergoes proteolysis by exogenous C1r; secreted C1s is also proteolysed by exogenous C1r. In the presence of immune-complex-bound C1q, secreted C1r and C1s are able to reconstitute C1, but normal activation requires extrinsic C1r2-C1s2.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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