Alpha-1-Antitrypsin

Acute Phase Protein

Acute-phase protein (Acute Phase Reactants)

• Acute-phase protein is raised in inflammatory conditions.
• When there is an increase in a protein called positive acute-phase protein.
  • In the case of a decrease in the acute phase protein, it is called the negative phase protein.
• The acute phase proteins (positive) are proteins whose concentration increases in the plasma, and after the disease episode is over, it decreases and may become normal.

Alpha-1-antitrypsin (AAT, α1-antitrypsin)

Sample for Alpha-1-Antitrypsin

1. It is done in the patient’s serum (collect 5 to 10 ml of blood).
2. Serum electrophoresis may be advised. 

Indications for Alpha-1-Antitrypsin

1. In case of a family history of emphysema.
2. Advised in children with cirrhosis and liver diseases.
3. Advised for acute inflammation, infection, or malignancy (non-specific test).
4. Drugs like oral contraceptives increase the AAT level.

Precautions for Alpha-1–antitrypsin (AAT, α1-antitrypsin)

1. Serum level of AAT increases during pregnancy.

Definition of Alpha-1-Antitrypsin

1. Alpha-1-Antitrypsin (AAT) is a serine protease inhibitor that inactivates trypsin, but its important function is the inactivation of neutrophil elastase that breaks down the elastic fiber and collagen.
2. Alpha-1-Antitrypsin is an autosomal recessive deficiency.
3. It is located on chromosome 14.
4. It is a serine protease inhibitor.

Pathophysiology of Alpha-1-antitrypsin (AAT, α1-antitrypsin)

1. This is a naturally occurring protease inhibitor.
2. This is synthesized and catabolized in the liver.
   1. Alpha-1-Antitrypsin (AAT) is synthesized in the liver.
   2. It comprises 90% of the globulins that migrate on electrophoresis in the alpha-1 region.
3. This is an important inhibitor of neutrophil elastase that is produced in phagocytosis by these cells.
4. This enzyme reacts with elastin in the tracheobronchial tree and vascular endothelium.
   1. This enzyme prevents the loss of elastic tissue function.
5. The Alpha-1-Antitrypsin (AAT) deficiency has been associated with two different diseases:
   1. Pulmonary emphysema in adults is relatively common.
   2. Cirrhosis in children is relatively rare.
6. Its deficiency leads to premature emphysema.

5. Its concentration increased much to fold in acute inflammation. It is increased in:
   1. Acute inflammatory disorders.
   2. Chronic inflammatory disorders.
   3. Stress.
   4. Any infection.
   5. Thyroid infection.

6. Cigarette smoke and volatile irritants lead to the release of proteolytic enzymes from the white blood cells.

7. This is a disease called AAT deficiency, which is an inherited condition.
   1. This disease can transfer from parents to children.
8. ATT is a protein that protects the lung. It is formed in the liver.

Signs and symptoms of Alpha-1-Antitrypsin (AAT) deficiency:

1. There is tiredness.
2. There is weight loss. 
3. Repeated lung infections.
4. There is shortness of breath and wheezing.
5. There may be a vision problem.
6. There may be tachycardia on standing.
7. This is increased in acute and chronic inflammation.

Normal level of Alpha-1–antitrypsin (AAT, α1-antitrypsin)

1. Newborn   =  145 to 270 mg/dL.
2. Adult          =  78 to 200 mg/dL.
3. Adult > 60 years   =  115 to 200 mg/dL.
4. Serum electrophoresis showed 90% of ATT in the α1-globulin.
5. Another source:
   1. 85 to 213 mg/dL (0.85 to 2.13 g/L).
6. Another source:
   1. 100 to 200 mg/dL (18.4 to 36.8 µmol/L) by nephelometry.

Alpha-1-Antitrypsin (AAT) is decreased in:

1. The level is typically <50 mg/dL.
2. Severe liver diseases.
3. Malnutrition.
4. Prematurity.
5. Renal losses like nephrosis.

Normal level of Alpha-1–antitrypsin (AAT, α1-antitrypsin)

1. Newborn   =  145 to 270 mg/dL.
2. Adult          =  78 to 200 mg/dL.
3. Adult > 60 years   =  115 to 200 mg/dL.
4. Serum electrophoresis showed 90% of ATT in the α1-globulin.
5. Another source:
   1. 85 to 213 mg/dL (0.85 to 2.13 g/L).
6. Another source:
   1. 100 to 200 mg/dL (18.4 to 36.8 µmol/L) by nephelometry.

Alpha-1–antitrypsin decreased in the following:

1. The level is <50 mg/dL.
2. Emphysema of the lungs.
3. In severe liver diseases.
4. Malnutrition.
5. Prematurity.
6. Renal losses in nephrosis.
7. G I losses have been seen in pancreatitis and protein-losing diseases.
8. Exudative dermatopathy.

Alpha-1–antitrypsin (AAT) increased in the following:

1. Acute and chronic infections, as an acute phase protein.
2. In malignancies like cervical cancer and lymphoma.
3. Use of birth control tablets.

Test value for the layman:

1. In the case of patients with emphysema.
2. In children, if they develop cirrhosis or liver diseases.

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