Den aktiverade formen av komplement 1, som uppvisar hydrolasaktivitet. I den klassiska komplementprocessen spjälkar den först C4 och sedan C2 till aktiva komponenter, varvid bildas ett nytt enzym, som benämns EAC142 eller C42 eller C3-konvertas.
A 77-kDa subcomponent of complement C1, encoded by gene C1S, is a SERINE PROTEASE existing as a proenzyme (homodimer) in the intact complement C1 complex. Upon the binding of COMPLEMENT C1Q to antibodies, the activated COMPLEMENT C1R cleaves C1s into two chains, A (heavy) and B (light, the serine protease), linked by disulfide bonds yielding the active C1s. The activated C1s, in turn, cleaves COMPLEMENT C2 and COMPLEMENT C4 to form C4b2a (CLASSICAL C3 CONVERTASE).
Inga svenska synonymer finns.
C1s, Complement — Complement 1s — C 1 Esterase — Esterase, C 1 — C1s Complement — Complement, C1s — Complement Component 1s — Component 1s, Complement — Complement 1 Esterase — Esterase, Complement 1 — C1 Esterase — Esterase, C1