Complement component C4 (CC4)

Component C4 (Cc4)

We remind you that independent interpretation of the results is unacceptable, the information provided below is for reference purposes only.

Component C4 (Cc4) is a glycoprotein that belongs to the complement system, which is a crucial part of the body's immune defense mechanism. The complement system is involved in various functions, including the elimination of pathogens, the removal of immune complexes, and the regulation of inflammatory processes.

Structure and Functions of Component C4

Component C4 is synthesized primarily by hepatocytes (liver cells) and is present in the bloodstream as an inactive precursor. It can be activated through different pathways, such as the classical pathway, the lectin pathway, or the alternative pathway. When activated, C4 undergoes a conformational change and interacts with other complement proteins to initiate the complement cascade.

The primary functions of Component C4 include:

• Opsonization: C4 helps mark pathogens or damaged cells for phagocytosis by immune cells, such as macrophages and neutrophils.
• Inflammation regulation: C4 participates in the regulation of inflammatory processes, contributing to the body's defense against infections and tissue damage.
• Immune complex clearance: C4 plays a role in the removal of immune complexes (antigen-antibody complexes) from the circulation, preventing their deposition in tissues and potential tissue damage.

Table 1: Structural Components of C4

The activation of C4 is a crucial step in the complement cascade, leading to the formation of various enzymes and protein complexes that contribute to the body's immune response against pathogens and the removal of harmful substances.

Role of Complement Component C4 (Cc4)

Complement Component C4 (Cc4) plays a crucial role in the complement system, which is a part of the innate immune system. The complement system is a complex network of proteins that helps to eliminate pathogens, remove cellular debris, and regulate inflammatory responses.

Indications for Complement Component C4 (Cc4) Testing

Complement Component C4 (Cc4) testing may be ordered in the following situations:

• Evaluation of autoimmune disorders: Abnormal levels of Cc4 can be associated with autoimmune diseases such as systemic lupus erythematosus (SLE), rheumatoid arthritis, and vasculitis.
• Investigation of immune deficiencies: Deficiencies in the complement system, including Cc4 deficiency, can increase susceptibility to recurrent infections.
• Monitoring of kidney diseases: Cc4 levels may be affected in certain kidney diseases, such as glomerulonephritis and nephritis.
• Hereditary angioedema: Cc4 testing can aid in the diagnosis and management of hereditary angioedema, a rare genetic disorder characterized by episodes of severe swelling.

Preparation for the C4 Complement Component (C4c) Test

No special preparation is typically required for the C4 Complement Component (C4c) test. However, it is recommended to inform your healthcare provider about any medications you are taking, as some drugs may potentially affect the test results.

Procedure for the C4 Complement Component (C4c) Test

The C4 Complement Component (C4c) test is performed by collecting a blood sample from a vein, typically in the arm. A healthcare professional will perform the venipuncture procedure, and the collected blood sample will be sent to a laboratory for analysis.

Calculation and Significance

The complement component 4 (C4) test is a part of the comprehensive metabolic panel (CMP) or basic metabolic panel (BMP) blood tests. It measures the level of the C4 protein, which is a component of the complement system in the body's immune response. The C4 test is often performed alongside other complement tests to evaluate the function of the complement system and aid in the diagnosis of immunological disorders.

Sources:

https://www.urmc.rochester.edu/encyclopedia/content.aspx?contenttypeid=167&contentid=complement_c4_blood
https://www.webmd.com/a-to-z-guides/what-is-complement-c4-test
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8317844/

IMPORTANT!

It is crucial to remember that the information provided in this section is not intended for self-diagnosis or self-treatment. If you experience any symptoms or a flare-up of a condition, it is essential to consult a healthcare professional for proper diagnosis and treatment. Only a qualified specialist can make an accurate diagnosis and determine the appropriate treatment. To ensure the most accurate and consistent evaluation of test results, it is recommended to conduct tests at the same laboratory. Different laboratories may use different methods and units of measurement for similar tests.