Gosset Molecular Classification
Enzyme, Serine protease, Multi-subunit protein complex
Other Names
Complement component 1, C1qrs complex
Disease Roles
Complement C1 complex Overview
The C1 complex is the first component of the classical complement pathway, composed of C1q, C1r, and C1s subunits. It initiates the pathway upon binding to antibody-antigen complexes, leading to activation of C1r and C1s serine proteases, which cleave downstream complement components and propagate the complement cascade. Dysregulation can lead to autoimmune and inflammatory diseases.
Mechanism of Action
Inhibition of C1r and C1s serine protease activity; preventing cleavage of downstream complement components C4 and C2
Biological Functions
Immune response
Complement activation (classical pathway)
Pattern recognition
Initiation of inflammation
Disease Associations
Autoimmune diseases
Inflammation
Hereditary angioedema
Neurodegenerative diseases
Safety Considerations
- Risk of infection with C1 inhibitors
- Thrombotic events
- Hypersensitivity reactions
Interacting Drugs
C1 esterase inhibitor (CINH)
Ruconest
Berinert
Other therapeutic inhibitors targeting C1 complex
Associated Biomarkers
| Biomarker |
|---|
| C4 levels |
| C1q levels |
| Autoantibodies against C1q |