Protein in the blood when performing biochemical analysis can say a lot about the state of health. In this case, the protein is a composite concept, since there are concepts of total protein, and there are separate fractions. And all these fractions are important for the human body.
Human blood is 54% plasma and 46% blood cells (erythrocyte, platelet, leukocyte cells). Plasma is a liquid portion of blood that contains water, a suspension of proteins, organic non-proteinaceous compounds and inorganic salts. Normally, about 6-8% of the total plasma are proteins. The most important plasma proteins are albumin, globulin fractions and fibrinogen.
Total protein in the blood – what is it
Total protein consists of albumin, fibrinogen and four globulin fractions (alpha1, alpha 2, beta and gamma globulins). The separation of proteins into fractions is based on their mobility during electrophoresis.
Also, proteins in the blood differ in solubility. Albumins are a type of protein soluble in water, globulins require the presence of salts to dissolve.
Almost all proteins (except immunoglobulins and peptide hormones) are synthesized by liver cells. Plasmocytes are responsible for the synthesis of immunoglobulins, and the production of peptide hormones is carried out by the glands of the endocrine system.
Albumin levels may increase with dehydration and thickening of the blood. An increase in this fraction is observed in intestinal and liver diseases, as well as in the presence of foci of purulent infection in the body.
To the presence of an infectious-inflammatory process, acute-phase proteins ( C-reactive proteins , haptoglobins, fibrinogen, etc.).
The life span of proteins in the blood ranges from several days to several weeks. Utilization of “aged” proteins occurs in the liver using endocytosis.
The role of protein in the body
Quantitatively, most of the total protein is represented by albumin (transthyretin and albumin). They make up from 50 to 70% of the total protein in the blood.
Transthyretin is prealbumin. This blood protein is responsible for the transportation of thyroid hormones: thyroxine and triiodothyronine.
Albumin acts as a protein reserve, maintains the colloid-osmotic balance of the blood, is responsible for the binding and transport of fatty acids (fatty acids), bilirubin and bile acids, SG (steroid hormones). Also, albumin transports inorganic calcium and magnesium ions.
What are the globulins for?
Alpha globulins include:
- alpha1 – antitrypsin, which acts as an inhibitor of proteolytic enzymes;
- thyroxin-binding protein in the blood that binds and transports the thyroid hormone thyroxin;
- retinol-binding protein that carries vitamin A (retinol);
- prothrombin , being the second blood clotting factor;
- lipid transporting lipoprotein;
- vitamin D-binding protein in the blood, binding and transporting calciferol;
- macroglobulin carrying zinc and proteinases;
- antithrombin 3, which inhibits blood clotting;
- copper ion transporting ceruloplasmin;
- transcortin that binds and transports hormones (cortisol and corticosterone).
The fraction of blood beta-globulin proteins will be divided into:
- transferin responsible for the binding and transfer of iron;
- haemopexin transporting heme;
- fibrinogen, the first blood coagulation factor;
- globulin that carries male and female sex hormones (testosterone and estrogen);
- C-reactive protein in the blood (acute phase protein, the first to respond to an acute inflammatory reaction);
- Transcobalamin, a cyanocobalamin transporter (vitamin B12).
The fraction of total protein in the blood, represented by gamma globulins, includes immunoglobulins:
- IgG, related to specific humoral protection factors;
- IgM involved in providing a primary immune response;
- IgA, preventing the fixation of pathogenic microorganisms on the mucous membranes;
- IgE, providing full antiparasitic immunity and involved in the reactions of allergic origin;
- IgD, which are receptors for B lymphocytic cells.
Indications for analysis of total protein in the blood
Total protein in the blood rate in men and women should be evaluated when:
- acute and chronic pathologies of an infectious-inflammatory nature;
- systemic autoimmune pathologies involving lesions of the connective tissue (collagenosis);
- dehydration, diarrhea, indomitable vomiting;
- damage to the kidneys or liver (especially in diseases that disturb the protein synthesis of the liver – cirrhosis, hepatitis and
Also, the total blood protein should be investigated in women during pregnancy, especially with the appearance of marked edema.
Preparation for analysis
Protein in the blood should be evaluated on an empty stomach, food intake is excluded twelve hours before the test. Drinking tea, coffee, juice and carbonated drinks on the eve of the study is not allowed. In the morning you can drink ordinary boiled water.
The day before the study excluded the use of fatty and fried foods.
Reception of alcohol is desirable to exclude 48 hours before blood sampling. In the morning, before blood sampling it is advisable not to smoke.
Also, the day before blood sampling is eliminated physical activity.
Total protein in the blood. The rate and what may affect the results of the study
Elevated protein in the blood can be observed on the background of treatment with drugs of androgens, clofibrate, corticotropin, corticosteroids, adrenaline, thyroid hormones, insulin, progesterone.
Protein in the blood may decrease with allopurinol or estrogen therapy.
Falsely elevated protein in the blood can be observed during active exercise before the test.
When applying an overly tight tourniquet or active hand work, a protein in the blood can also be falsely elevated.
Total protein in the blood rate in patients older than 16 years is from 65 to 85 grams per liter.
The total protein norm in children is presented in the table:
In some laboratories, the result of a fraction test can be recorded as a percentage: (test fraction / total protein in the blood) * 100%
Protein increased in the blood – what does it mean
- acute and chronic pathologies of an infectious-inflammatory nature;
- dehydration, as a result of increased sweating, diarrhea, indomitable vomiting, extensive burn lesions, loss of fluid in diabetes insipidus;
- systemic autoimmune pathologies involving lesions of the connective tissue;
- tropical diseases;
- specific hypergammaglobulinemia;
- chronic polyarthritis;
- the active phase of chronic hepatitis or liver cirrhosis;
- malignant neoplasms, accompanied by increased synthesis of the pathological protein. This picture can be observed in multiple myeloma, macroglobulinemia, lymphogranulomatosis, “diseases of heavy chains.”
The increase in total protein in the blood (hyperproteinemia) should be divided into relative and absolute.
With an absolute increase, the level of total protein can rise to 120 grams or more per liter.
Absolute increase in total protein
Significant hyperproteinemia can occur with Waldenstrom macroglobulinemia. This disease is a type of malignant monoclonal gammapathy, manifested by hypersecretion of the viscous and high molecular weight protein Waldenstrom (a type of immunogdobulin M).
The overproduction of proteins in this disease is associated with damage to the lymphocytic and plasma cells of the bone marrow.
With this disease, blood viscosity increases significantly and the risk of thrombosis increases.
Symptoms of the disease are complaints to:
- constant weakness
- weight loss
- swollen lymph nodes
- joint pain,
- hearing loss
- the appearance of a reddish skin tone,
- reduced vision
Also characterized by the appearance of hemorrhages on the skin, nasal and gingival bleeding. In some cases, intestinal bleeding is possible.
- unreasonable weight loss
- profuse night sweats
- shortness of breath
- compulsive dry cough
- increase in all groups of lymph nodes,
- constant lethargy and weakness
- low-grade fever
- itching of the skin.
Also, with Hodgkin’s disease, there is a significant decrease in immunity, frequent viral (usually herpetic), bacterial and fungal infections develop.
Heavy chain disease
By this common name is meant a group of rare diseases, accompanied by an increased excretion in urine of heavy immunoglobulin chains of monoclonal nature. This is due to the fact that all immunoglobulins synthesized in the body are defective – they lack light chains.
Manifested as follows:
- hepatolienal symptom (enlarged liver and spleen),
- severe diarrhea,
- severe pain in the abdomen and joints,
- an increase in the size of the lymph nodes
- severe intoxication and exhaustion.
Low protein in the blood. The reasons
Total protein in the blood is reduced when:
- alimentary hypoproteinemia associated with reduced protein intake with food. Such a pattern can be observed with a strict diet or fasting;
- impaired intestinal absorption (enterocolitis, malabsorption syndrome);
- conditions after surgery, as well as after injuries or burns;
- liver diseases, accompanied by a violation of its protein synthesis function;
- increased, pathological loss of protein, as a result of bleeding, kidney disease with nephrotic syndrome (glomerulonephritis), ascites, diabetes mellitus;
- prolonged fever (hyperthermia);
- prolonged immobility (forced bed rest, immobilization after injury);
- malignant neoplasms;
- heavy physical training, especially with reduced or insufficient protein intake;
- thyroid diseases;
How to increase protein in the blood
First of all, the reason for the change in the analysis should be identified. In the presence of concomitant diseases, accompanied by pathological loss of protein, the main pathology is treated.
If the protein level is reduced due to increased physical exertion or improper diet, the protein in the blood can be restored when the diet and lifestyle is normalized.