Globulins in the blood: types
When conducting a biochemical blood test, the quantitative content of total protein is determined in it. It is represented by proteins that are present in plasma. There are several proteins in the human blood, they all have differences in their structure, and also perform different functions. There are only five protein fractions in the blood, including: alpha-1 (α1), alpha-2 (α2), beta-1 (β1), beta-2 (β2) and gamma (γ). The beta-1 and beta-2 globulins are not determined separately, as they have no diagnostic value.
Content:
- Protein fractions of blood
- The quantitative ratio of protein fractions
- Alpha globulins
- Beta globulins
- Gamma globulins
- Analysis for blood globulins: what is the value?
Protein fractions of blood
An analysis that allows you to calculate the number of protein fractions in the blood is called a proteinogram. The doctor will be interested in the level of albumin in the blood (this protein is soluble in water) and globulins (these proteins do not dissolve in water, but disintegrate when exposed to an alkaline or saline environment).
High and low levels of proteins in the blood are not normal. Their imbalance characterizes certain disorders: immune, metabolic or metabolic.
With an insufficient content of albumin in the blood, liver dysfunction can be suspected, which is not able to provide the body with proteins. It is also possible disruptions in the functioning of the kidneys or organs of the digestive system, as a result of which albumin will be excreted too quickly from the body.
If the level of protein in the blood is elevated, then this may be due to inflammatory processes. However, sometimes a similar situation is observed in completely healthy people.
To calculate exactly which proteins in the body are deficient or surplus, they are divided into fractions using the electrophoresis method. In this case, the amount of total protein and fractions will be indicated on the analysis form. Most often, doctors are interested in the values of albumin + globulins (albumin-globulin coefficient). Its normal values vary within 1.1-2.1.
Protein fractions rates
| Protein fraction | Norm g / l | Group ratio in percent |
| Total protein | 65-85 | |
| Albumen | 35-55 | 54-65 |
| Alpha-1 | 1.4-3.0 | 2-5 |
| Alpha-2 | 5.6-9.1 | 7-13 |
| Beta globulins | 5.4-9.1 | 8-15 |
| Gamma globulins | 8.1-17.0 | 12-22 |
| Fibrinogen * | 2.0-4.0 | |
| Albumin Globulin Ratio | 1.1-2.1 |
Unlike other biological media, there is no fibrinogen in blood serum.
The amount of protein fractions will differ depending on the age of the person.
| Age group | Albumin level in g / l | Alpha-1 in g / l | Alpha-2 in g / l | Beta in g / l | Gamma in g / l |
| Newborn baby (first seven days of life) | 32.5-40.7 | 1.2-4.2 | 6.8-11.2 | 4.5-6.7 | 3.5-8.5 |
| A child older than seven days and up to a year | 33.6-42.0 | 1.24-4.3 | 7.1-11.5 | 4.6-6.9 | 3.3-8.8 |
| 1-5 years old | 33.6-43.0 | 2.0-4.6 | 7.0-13.0 | 4.8-8.5 | 5.2-10.2 |
| 5-8 years old | 33.0-47.1 | 2.0-4.2 | 8.0-11.1 | 5.3-8.1 | 5.3-11.8 |
| 8-11 years old | 40.6-45.6 | 2.2-3.9 | 7.5-10.3 | 4.9-7.1 | 6.0-12.2 |
| 11-21 years | 38.9-46.0 | 2.3-5.3 | 7.3-10.5 | 6.0-9.0 | 7.3-14.3 |
| Over 21 | 40.2-50.6 | 2.1-3.5 | 5.1-8.5 | 6.0-9.4 | 8.1-13.0 |
Please note that the normal values may differ from the figures presented above, since each laboratory will have its own reference values.
The quantitative ratio of protein fractions
Most of all in the blood is albumin.
Depending on the proportion of the protein fraction present in the blood serum, they are distributed as follows (in descending order):
- Albumin - 55-65%.
- Gamma globulins - 12-22%.
- Beta globulins - 8-12%.
- Alpha-2-globulins - 6-12%.
- Alpha-1-globulins - 2-4%.
- Fibrinogen - about 2%.
Alpha globulins
Alpha globulins are charged in the same way as albumin, but they are superior in size. If inflammation develops in the human body, then their number increases sharply. Therefore, alpha proteins are considered acute phase proteins due to their qualitative composition.
Alpha-1-globulins contain the following components:
- Alpha-1-antitrypsin, which produces proteolytic enzymes.
- Alpha-acid glycoprotein, which helps reduce inflammation.
- Prothrombin, which is responsible for blood clotting processes.
- Alpha-1-lipoproteins, which transport lipids to tissue cells.
- A thyroxine-binding protein that finds thyroxine (a protein produced by the thyroid gland) in the blood and transports it to the desired cells.
- Transcortin is a globulin that is responsible for transporting cortisol.
Alpha-2-globulins are represented by the following components:
- Alpha-2-macroglobulin, which is responsible for the body's immune response. It begins to work actively when an inflammatory reaction develops in the body or when an infection enters it.
- A glycoprotein is a haptoglobulin that is bound to hemoglobin. With the destruction of red blood cells in the blood, the level of free haptoglobulin increases.
- Ceruloplasmin is a metalloglycoprotein that is responsible for transporting copper from the blood to tissue cells. Also, this component of alpha-2-globulins is an antioxidant, and it also participates in the oxidation of serotonin, vitamin C, norepinephrine and other substances.
- Apolipoprotein B, which carries molecules of "bad" cholesterol.
Alpha globulins are produced by hepatocytes. There are more of them in the body with an allergic reaction, against the background of inflammation, stress, injury. Therefore, these proteins are called acute phase.
The level of alpha-proteins in the blood can increase not only in acute inflammation, but also in subacute and even chronic course of the disease.
The jumps of these protein fractions are characteristic for the following pathological conditions:
- Pneumonia and other inflammatory reactions in the lung tissue.
- Tuberculosis with exudate.
- Penetration of any infection into the body.
- Traumatic damage to body tissues, burns and previous operations.
- Acute joint inflammation, rheumatic fever.
- Cancer neoplasms of a malignant nature.
- Sepsis.
- Necrotic tissue damage.
- Taking male sex hormones.
- Kidney disease. In this case, alpha proteins will increase in the blood, while the remaining protein fractions will be deficient.
Low levels of alpha globulins are observed in respiratory failure and intravascular hemolysis.
Beta globulins
Beta globulins are represented by beta-1 and beta-2 protein fractions.
Together, they perform the following functions in the body:
- Transferrin in beta-globulins is responsible for the transport of iron.
- Hemopexin binds to hemoglobin and removes its excess from the body.
- The beta-fractions of the protein component of the blood take part in the formation of the immunological reaction.
- Beta-lipoproteins carry cholesterol and phospholipids, are directly involved in metabolic processes and the development of atherosclerosis.
If the level of beta-fractions in the body rises, then this may indicate a disease that is accompanied by the accumulation of lipids in the body, as well as pathology of the cardiovascular system.
Sometimes the amount of beta proteins increases in the body of a woman carrying a baby.
In addition, the following diseases can lead to an increase in the level of beta-proteins:
- Malignant cancerous tumors.
- Progressive tuberculosis.
- Hepatitis.
- Obstructive jaundice.
- Iron-deficiency anemia.
- Myelomas and monoclonal gammopathies.
- Taking estrogen.
The level of beta-globulins decreases in inflammatory diseases, in infectious processes in the body, in diets with limited food intake in the body, in pathologies of the gastrointestinal tract.
Gamma globulins
Gamma globulins contain acquired and natural antibodies that are responsible for the functioning of humoral immunity. Modern science knows 5 classes of gamma globulins, which are presented in the table.
| Immunoglobulins | Percentage of globulins in serum | Description of gamma globulins |
| lgG | About 75% | They have an antioxidant effect, fight against viruses and gram-positive bacterial flora |
| lgA | About 13% | Active against capsular bacteria, as well as against anti-insular antibodies that appear in the blood in diabetes mellitus |
| lgM | About 12% | Active against gram-negative flora, take part in the suppression of serum sickness and syphilis |
| lgE | 0.0 … | Appears in the blood in response to an allergic reaction |
| lgD | Present in the blood of the fetus, only traces of these gamma globulins can be detected in adults and children | Do not have any clinical significance |
The amount of gamma globulins in the blood varies depending on the person's age.
| Human age | The level of immunoglobulins in the blood in g / l | ||
| lgM | lgA | lgG | |
| Children under 3 years old | 0.5-0.2 | 0.2-1.5 | 4.5-11.0 |
| Children 4-5 years old | 0.4-2.0 | 0.25-1.5 | 4.5-12.5 |
| Children 6-8 years old | 0.5-2.0 | 0.3-2.0 | 6.3-13.0 |
| Children 9-10 years old | 0.5-2.5 | 0.45-2.5 | 6.0-16.0 |
| Adults and children over 10 years old | 0.55-3.5 | 0.7-3.15 | 0.7-3.5 |
A high level of gamma globulins will be observed in the following pathological conditions:
- Any inflammatory process occurring in a chronic form with localization in the area of the joints, biliary or urinary system.
- Infections affecting liver cells.
- Poisoning accompanied by damage to the hepatic parenchyma.
- Cirrhosis of the liver.
- Obstructive jaundice.
- Pulmonary tuberculosis.
- Infection of the body with parasites.
- Autoimmune diseases.
- Bronchial asthma.
- Sarcoidosis of the lungs.
- Multiple myeloma, chronic lymphocytic leukemia, Waldenstrom's macroglobulinemia.
- The last stage of HIV.
A decrease in the level of gamma globulins is observed with the following pathologies:
- AIDS.
- Radiation sickness.
- Splenectomy.
- Treatment with cytostatics.
- Lymphosarcoma, Hodgkin's lymphoma.
- Kidney damage with the development of nephrotic syndrome.
- Infections and purulent inflammation, which has a protracted course.
- Malnutrition in childhood.
- Congenital forms of hypogammaglobulinemia and agammaglobulinemia.
During gestation, women may experience a decrease in serum gamma globulin levels. Also, the decrease in their numbers is facilitated by the passage of treatment with corticosteroids and the performance of plasmapheresis.
Analysis for blood globulins: what is the value?
Not always indicators of the level of total protein in the blood give complete information about the existing disease. Therefore, doctors perform an analysis to determine the various protein fractions.
This allows you to clarify the diagnosis and prescribe the correct treatment:
- An acute inflammatory reaction will be indicated by an increase in blood alpha-globulins (alpha-1 and alpha-2). In this case, a viral infection can be suspected, which is concentrated in the lungs, bronchi, heart or kidneys. Also, their jump is observed with the development of a tumor in the body, or after receiving a serious injury. The transferred surgical interventions lead to an increase in the level of alpha globulins.
- Gamma globulins increase in the blood in diseases that have a chronic course. For example, with rheumatoid arthritis or liver cirrhosis.
Proteinogram is prescribed for acute inflammatory processes in the body, which are caused by various factors. The ratio of the level of protein fractions allows you to detect bowel diseases, as well as depletion of the body. Also, this laboratory study makes it possible to detect hidden infections, it is used to control the therapy being carried out.
The author of the article: Shutov Maxim Evgenievich | Hematologist
Education: In 2013 he graduated from the Kursk State Medical University and received a diploma "General Medicine". After 2 years, completed residency in the specialty "Oncology". In 2016 completed postgraduate studies at the National Medical and Surgical Center named after N. I. Pirogov.
