C1-inhibitor (C1-inh, C1 esterase inhibitor) is a protease inhibitor belonging to the serpin superfamily.[5] Its main function is the inhibition of the complement system to prevent spontaneous activation but also as the major regulator of the contact system.[6][7]
^Cicardi M, Zingale L, Zanichelli A, Pappalardo E, Cicardi B (November 2005). "C1 inhibitor: molecular and clinical aspects". Springer Seminars in Immunopathology. 27 (3): 286–98. doi:10.1007/s00281-005-0001-4. PMID16267649. S2CID24583403.