The complement C4-A blood test measures the levels of complement component 4A (C4-A) in the blood. The complement system is a part of the immune system that plays a crucial role in the body’s defense against infections and the clearance of damaged or abnormal cells. Complement C4-A is a specific subtype of the complement protein C4.
Key points:
Complement System: The complement system consists of a group of proteins that work together to enhance the immune response. Complement proteins play roles in inflammation, opsonization (marking of pathogens for destruction), and cell lysis (breaking down of cells).
Abnormalities: Abnormalities in complement proteins, including C4-A, may be seen in conditions such as autoimmune diseases, rheumatoid arthritis, systemic lupus erythematosus (SLE), hereditary angioedema, infections, and certain kidney diseases.
Genetic Variants: Some individuals may have genetic variations in the C4-A gene, leading to different levels of C4-A protein production. These variations are associated with autoimmune and inflammatory conditions.
Diagnostic Marker: Testing complement C4-A levels in the blood can be used as a diagnostic marker for certain autoimmune conditions. Low levels or deficiencies in complement C4-A may suggest an increased risk or presence of autoimmune diseases.
Monitoring Disease Activity: In some cases, complement C4-A levels may be monitored over time to assess disease activity and response to treatment in autoimmune conditions.