Basophilic leukocytes are the largest cells from granulocytes and at the same time are the smallest. They are formed in the stagnant brain from myeloblasts, after which they enter the blood, where only a few hours are. Then they move to the tissues and function there for up to 12 days. The basophils are round in shape, the nucleus is staboid or segment-nucleated. The cytoplasm of cells contains granules of different shapes and sizes, which are called basophilic granules.
Cytoplasmic granules contain proteins and enzymes, which determine the functions of basophils. Such bioactive substances include histamine, heparin, serotonin and others.
The main one is histamine. Thanks to it, the smooth muscles contract, the vascular permeability increases. This leads to the formation of edema of the tissues, lowering blood pressure, increasing the viscosity of the blood, contributes to the process of phagocytosis.
Basophils easily detectable in the blood smear
Heparin is considered to be the second most important bioactive substance. It is a histamine antagonist, which leads to the dilution of blood.
Serotonin dilates blood vessels, stimulates platelet activity, increases vascular permeability.
The chemotactic eosinophilic factor found in basophils participates in the attraction of eosinophils to the inflammation zone.
On the surface of the basophilic granulocyte is immunoglobulin E. When it comes into contact with the allergen, degranulation of basophils occurs, resulting in the release of active substances from the granules.
These cells are able to migrate from the blood to the tissues and move into them. Tissue basophils and basophils in the blood perform the following functions of :
- maintains blood in small vessels;
- facilitate the transfer of other leukocytes to the tissue through the capillary wall to the location of the harmful agent;
- are responsible for the growth of new capillaries and trophic tissue;
- are actively fighting worms;
- protect the skin, mucous membrane and intestines when infected with mites and helminths;
- block in the tissues of the poisons of insects and prevent them from spreading;
- are involved in the development of allergic reactions;
- is capable of phagocytosis, although this is not their primary function;
- cleans tissues from bioactive substances, synthesizes and accumulates them in granules, then is removed.
The content of basophils can be absolute and relative. The absolute amount is normally from 0.01 to 0.065 x 10⁹ per liter of blood for all. The percentage of basophils from the total number of leukocytes is not the same at different ages. The relative content is within the limits of:
- from 0.5 to 1% in an adult;
- 0,75% at birth;
- from 0,4 to 0,9% in children under 1 year;
- from 0.6% to 21 years.
Causes of low level
The condition in which basophils are lowered is called basepenia. At the same time, their level falls below 0.01X10⁹ per liter. The causes of low basophils may be as follows:
- Acute infectious diseases.
- Acute pneumonia.
- Strong stress.
- Syndrome Itenko-Cushing.
- Hyperfunction of the thyroid gland.
- Taking some medications.
- Consequences of chemotherapy.
- Relative indicator is low during recovery period in infectious diseases.
Any deviation of basophil levels should not be left without medical attention
If estrogens can enhance the formation of basophils, then glucocorticosteroids and another female hormone - progesterone, on the contrary, reduce their level. The reasons for increasing basophils can be found in this article.
Basophils in pregnancy
Low basophils are observed during pregnancy in women in a general blood test in the first trimester. This is due to the fact that during this period the volume of blood rapidly increases, namely its liquid part, while the number of cells remains unchanged, but their concentration decreases in the withdrawn portion of blood. This state is considered normal.
A reduced level or absence of basophils in the blood is not a diagnostic feature. Such a condition can accompany a number of pathologies or be conditioned physiologically. If this figure does not correspond to the norm, you need to find out the reason and make a diagnosis. Basophils are a small group of white blood cells, but they perform important specific functions, and any change in their composition can be a signal about the disease.