Alpha-2-macroglobulin (A2M) is the largest non-globulin protein and a key component of the alpha-2-globulin fraction, performing various functions. It inhibits non-specific plasma proteases, transports cytokines, growth factors, and hormones, participates in immune and inflammatory responses, and exhibits immunosuppressive properties.
A2M also plays a role in regulating enzyme cascades of the complement system, the kallikrein-kinin system, blood coagulation, and fibrinolysis.
Synthesis and Distribution
A2M is synthesized in the liver and enters the bloodstream, but due to its large size, it does not significantly diffuse into other bodily fluids.
Physiological Increase in A2M Levels
A2M levels naturally increase during:
- Embryogenesis
- Pregnancy
- Childhood and adolescence, as well as during periods of active growth, development, and differentiation
A2M is estrogen-associated, meaning that women of reproductive age tend to have slightly higher levels than men. In children, A2M levels are approximately twice as high as in adults, but they decrease to adult levels during adolescence.
Biomaterial: Venous blood.
Pre-test recommendations:
- Do not eat for 12 hours before the test.
- Stop taking medications 24 hours before the test (with your doctor’s approval).
- Avoid alcohol for 24 hours before the test.
- Do not smoke for 3 hours before the test.
- Assessment of liver fibrosis risk in patients with chronic liver diseases
- Diagnosis of liver fibrosis in individuals with chronic liver conditions
- Diagnosis of nephrotic syndrome – A2M levels increase in proportion to the severity of protein loss in urine
- Evaluation of patients with nephrotic syndrome
- Assessment of kidney tumors, benign prostatic hyperplasia, and prostate cancer
- Monitoring patients with long-term diabetes mellitus
Causes of Elevated Alpha-2-Macroglobulin Levels:
- Liver fibrosis
- Nephrotic syndrome
- Diabetes mellitus
- Benign prostatic hyperplasia
- Pregnancy
Causes of Decreased Alpha-2-Macroglobulin Levels:
- Acute pancreatitis
- Prostate carcinoma
- Myocardial infarction
- Surgical procedures with massive blood loss