What is the main function of leukocytes? Defense mechanisms of the body - functions of leukocytes

Which are characterized by the absence of color, the presence of a nucleus and the ability to move. The name is translated from Greek as “white cells”. The group of leukocytes is heterogeneous. It includes several varieties that differ in origin, development, appearance, structure, size, shape of the nucleus, functions. Leukocytes are produced in lymph nodes and bone marrow. Their main task is to protect the body from external and internal “enemies”. Leukocytes are found in the blood and various organs and tissues: in the tonsils, in the intestines, in the spleen, in the liver, in the lungs, under the skin and mucous membranes. They can migrate to all parts of the body.

White cells are divided into two groups:

Granular leukocytes - granulocytes. They contain large kernels irregular shape, consisting of segments, the greater the number of which, the older the granulocyte. This group includes neutrophils, basophils and eosinophils, which are distinguished by their perception of dyes. Granulocytes are polymorphonuclear leukocytes. .
Non-granular - agranulocytes. These include lymphocytes and monocytes, containing one simple nucleus oval shape and without characteristic granularity.

Where are they formed and how long do they live?

The bulk of white cells, namely granulocytes, are produced by red bone marrow from stem cells. From the maternal (stem) cell, a precursor cell is formed, then passes into a leukopoietin-sensitive cell, which, under the influence of specific hormone develops along the leukocyte (white) series: myeloblasts - promyelocytes - myelocytes - metamyelocytes (young forms) - band - segmented. Immature forms are found in the bone marrow, while mature forms enter the bloodstream. Granulocytes live for about 10 days.

The lymph nodes produce lymphocytes and a significant proportion of monocytes. Some agranulocytes from lymphatic system enters the blood, which carries them to the organs. Lymphocytes live a long time - from several days to several months and years. The lifespan of monocytes ranges from several hours to 2-4 days.

Structure

The structure of leukocytes of different types is different, and they look different. What they all have in common is the presence of a core and the absence of their own color. The cytoplasm can be granular or homogeneous.

Neutrophils

Neutrophils are polymorphonuclear leukocytes. They have round shape, their diameter is about 12 microns. There are two types of granules in the cytoplasm: primary (azurophilic) and secondary (specific). Specific small, lighter ones and make up about 85% of all granules, contain bactericidal substances and the protein lactofferin. Ausorophilic ones are larger, they contain about 15%, they contain enzymes, myeloperoxidase. In a special dye, the granules are colored lilac, and the cytoplasm is colored pink. The granularity is fine, consists of glycogen, lipids, amino acids, RNA, enzymes, due to which the breakdown and synthesis of substances occurs. In young forms, the nucleus is bean-shaped, in rod-nuclear forms it is in the form of a stick or a horseshoe. In mature cells - segmented - it has constrictions and looks divided into segments, which can be from 3 to 5. The nucleus, which can have processes (appendages), contains a lot of chromatin.

Eosinophils

These granulocytes reach a diameter of 12 microns and have a monomorphic coarse granularity. The cytoplasm contains oval and spherical shape. The grain is colored with acidic dyes in pink, the cytoplasm becomes blue. There are two types of granules: primary (azurophilic) and secondary, or specific, filling almost the entire cytoplasm. The center of the granules contains a crystalloid, which contains the main protein, enzymes, peroxidase, histaminase, phospholipase, zinc, collagenase, cathepsin. The eosinophil nucleus consists of two segments.

Basophils

This type of leukocyte with polymorphic granularity has dimensions from 8 to 10 microns. Granules different sizes stained with a basic dye in a dark blue-violet color, the cytoplasm - pink. The grain contains glycogen, RNA, histamine, heparin, and enzymes. The cytoplasm contains organelles: ribosomes, endoplasmic reticulum, glycogen, mitochondria, Golgi apparatus. The core most often consists of two segments.

Lymphocytes

By size they can be divided into three types: large (from 15 to 18 microns), medium (about 13 microns), small (6-9 microns). The latter are in the blood most of all. Lymphocytes are oval or round in shape. The nucleus is large, occupies almost the entire cell and is stained blue. A small amount of cytoplasm contains RNA, glycogen, enzymes, nucleic acids, and adenosine triphosphate.

Monocytes

These are the largest white cells, which can reach a diameter of 20 microns or more. The cytoplasm contains vacuoles, lysosomes, polyribosomes, ribosomes, mitochondria, and the Golgi apparatus. The nucleus of monocytes is large, irregular, bean-shaped or oval, may have bulges and indentations, and is colored reddish-violet. The cytoplasm acquires a gray-blue or gray-blue color under the influence of the dye. It contains enzymes, saccharides, and RNA.

Leukocytes in the blood healthy men and women are contained in the following ratio:

segmented neutrophils – from 47 to 72%;
band neutrophils – from 1 to 6%;
eosinophils – from 1 to 4%;
basophils – about 0.5%;
lymphocytes – from 19 to 37%;
monocytes – from 3 to 11%.

The absolute level of leukocytes in the blood in men and women normally has the following values:

band neutrophils – 0.04-0.3X10⁹ per liter;
segmented neutrophils – 2-5.5X10⁹ per liter;
young neutrophils – absent;
basophils – 0.065X10⁹ per liter;
eosinophils – 0.02-0.3X10⁹ per liter;
lymphocytes – 1.2-3X10⁹ per liter;
monocytes – 0.09-0.6X10⁹ per liter.

Functions

The general functions of leukocytes are as follows:

Protective – consists in the formation of specific and nonspecific immunity. The main mechanism is phagocytosis (capture by the cell pathogenic microorganism and taking his life).
Transport - lies in the ability of white cells to adsorb amino acids, enzymes and other substances found in plasma and transport them to the right places.
Hemostatic - involved in blood clotting.
Sanitary – the ability, with the help of enzymes contained in leukocytes, to dissolve tissues that have died due to injury.
Synthetic – the ability of some proteins to synthesize bioactive substances (heparin, histamine and others).

Each type of leukocyte has its own functions, including specific ones.

Neutrophils

The main role is to protect the body from infectious agents. These cells capture bacteria into their cytoplasm and digest them. In addition, they can produce antimicrobial substances. When an infection enters the body, they rush to the site of penetration, accumulate there in large quantities, absorb microorganisms and die themselves, turning into pus.

Eosinophils

When infected with worms, these cells penetrate the intestines, are destroyed and excrete toxic substances that kill helminths. In allergies, eosinophils remove excess histamine.

Basophils

These leukocytes take part in the formation of all allergic reactions. They are called first aid for bites of poisonous insects and snakes.

Lymphocytes

They constantly patrol the body in order to detect foreign microorganisms and out-of-control cells of their own body, which can mutate, then quickly divide and form tumors. Among them there are informants - macrophages, which constantly move throughout the body, collect suspicious objects and deliver them to lymphocytes. Lymphocytes are divided into three types:

T lymphocytes are responsible for cellular immunity, come into contact with harmful agents and destroy them;
B lymphocytes identify foreign microorganisms and produce antibodies against them;
NK cells. These are real killers who maintain normal cellular composition. Their function is to recognize defective and cancer cells and destroy them.

How to count

To count leukocytes, an optical device is used - the Goryaev camera

White cell (WBC) levels are determined during clinical analysis blood. Leukocyte counting is carried out using automatic counters or in a Goryaev chamber, an optical device named after its developer, a professor at Kazan University. This device is different high accuracy. Consists of thick glass with a recess rectangular shape(the camera itself), where a microscopic mesh is applied, and a thin cover glass.

The calculation is as follows:

Acetic acid (3-5%) tints methylene blue and pour into a test tube. Blood is drawn into a capillary pipette and carefully added to the prepared reagent, after which it is mixed thoroughly.
The coverslip and chamber are wiped dry with gauze. A coverslip is rubbed against the chamber to create colored rings, fill the chamber with blood and wait for a minute until cell movement stops. Count the number of leukocytes in one hundred large squares. Calculated using the formula X = (a x 250 x 20): 100, where “a” is the number of leukocytes in 100 squares of the chamber, “x” is the number of leukocytes in one μl of blood. The result obtained from the formula is multiplied by 50.

Conclusion

Leukocytes are a heterogeneous group of blood elements that protect the body from external and internal diseases. Each type of white cell performs a specific function, so it is important that their content is normal. Any deviations may indicate the development of diseases. A blood test for leukocytes allows early stages suspect pathology, even if there are no symptoms. This contributes timely diagnosis and gives a better chance of recovery.

Human blood consists of liquid substance(plasma) is only 55-60%, and the rest of its volume falls on the share of formed elements. Perhaps their most surprising representative are leukocytes.

They are distinguished not only by the presence of a core, especially large size and unusual structure - the unique function assigned to this shaped element. This, as well as other features of leukocytes, will be discussed in this article.

What does a leukocyte look like and what shape does it have?

Leukocytes are spherical cells with a diameter of up to 20 microns. Their number in humans ranges from 4 to 8 thousand per 1 mm3 of blood.

It is impossible to answer the question of what color a cell is - leukocytes are transparent and are defined by most sources as colorless, although the granules of some nuclei can have a fairly wide color palette.

The variety of types of leukocytes made it impossible to unify their structure.

Segmented.
Unsegmented.

Cytoplasm:

Grainy;
Homogeneous.

In addition, the organelles that make up the cells differ.

The structural feature that unites these seemingly dissimilar elements is the ability for active movement.

Young cells are producedfrom multipotent stem cells in the bone marrow. At the same time, to generate a workable leukocyte 7-9 divisions may be involved, and the place of the divided stem cell is taken by a clone cell of the neighboring one. This maintains population constancy.

Origin

The process of formation of leukocytes can be completed:

Lifespan

Each type of leukocyte has its own life expectancy.

This is how long cells live healthy person:

from 2 hours to 4 days –
from 8 days to 2 weeks – granulocytes;
from 3 days to 6 months (sometimes up to several years) – lymphocytes.

The shortest life expectancy characteristic of monocytes is due not only to their active phagocytosis, but also to the ability to give rise to other cells.

From a monocyte can develop:

The death of leukocytes can occur for two reasons:

Natural “aging” of cells, that is, the completion of their life cycle.
Cell activities associated with phagocytic processes– fight against foreign bodies.

The fight against leukocytes foreign body

In the first case, the function of destroying leukocytes is assigned to the liver and spleen, and sometimes to the lungs. Cell breakdown products are eliminated naturally.

The second reason is related to the course of inflammatory processes.

Leukocytes die directly "on duty" and if their removal from there is impossible or difficult, the products of cell breakdown form pus.

Video - Classification and significance of human leukocytes

The general function in which all types of leukocytes participate is - protecting the body from foreign bodies.

The task of cells is to detect and destroy them in accordance with the principle "antibody-antigen".

Destruction unwanted organisms occurs through their absorption, while the receiving phagocyte cell significantly increases in size, perceives significant destructive loads and often dies.

The site of death of a large number of leukocytes is characterized by swelling and redness, sometimes by suppuration and increased temperature.

An analysis of its variety will help to more accurately indicate the role of a specific cell in the process of fighting for the health of the body.

Thus, granulocytes perform the following actions:

Neutrophils– capture and digest microorganisms, stimulate the development and division of cells.
Eosinophils– neutralize foreign proteins found in the body and its own dying tissues.
Basophils– promote blood clotting, regulate vascular permeability by blood cells.

The list of functions assigned to agranulocytes is more extensive:

T lymphocytes– provide cellular immunity, destroy foreign cells and pathological cells of body tissues, counteract viruses and fungi, influence the process of blood formation and control the activity of B-lymphocytes.
B lymphocytes– support humoral immunity, fight bacterial and viral infections by generating antibody proteins.
Monocytes– perform the function of the most active phagocytes, which became possible thanks to a large number cytoplasm and lysosomes (organelles responsible for intracellular digestion).

Only in case of coordinated and coordinated work All types of leukocytes can maintain the health of the body.

IN modern diagnostics calculating the number of leukocytes is considered one of the most important laboratory research. After all, the rapidity of increase in the concentration of white blood cells indicates how strong the immune system is and the body’s ability to protect itself from damage. It could be a simple cut on your finger. living conditions, infection, fungus and virus. How leukocyte cells help cope with foreign agents will be discussed in the article.

Leukocytes are white blood cells, with medical point vision - heterogeneous groups of cells, different in appearance and functional purpose. They form a reliable line of defense for the body against adverse external influence, bacteria, microbes, infections, fungi and other foreign agents. They are distinguished by the presence of a nucleus and the absence of their own color.

The structure of white cells

The structure and functions of cells differ, but they all have the ability to emigrate through capillary walls and move through the bloodstream to absorb and destroy foreign particles. During inflammation and diseases of an infectious or fungal nature, leukocytes increase in size, absorbing pathological cells. And over time, they self-destruct. But as a result they are released harmful microorganisms which caused the inflammatory process. In this case, swelling, increased body temperature and redness of the site of inflammation are observed.

Terms! Chemotaxis of leukocytes is their migration to the site of inflammation from the bloodstream.

Particles that cause an inflammatory reaction attract required quantity white leukocytes to fight foreign bodies. And in the process of struggle they are destroyed. Pus is a collection of dead white blood cells.

Where are leukocytes produced?

In the process of securing protective function leukocytes produce protective antibodies that manifest themselves during inflammation. But most of them will die. Place of formation of white cells: bone marrow, spleen, lymph nodes and tonsils.

Terms! Leukopoiesis is the process of the appearance of leukocyte cells. Most often this occurs in the bone marrow.

How long do leukocyte cells live?

The lifespan of leukocytes is 12 days.

Leukocytes in the blood and their norm

To determine the level of leukocytes, it is necessary to conduct a general blood test. The units for measuring the concentration of leukocyte cells are 10*9/l. If tests show a volume of 4-10*9/l, you should be happy. For a healthy adult, this is a normative value. For children, the leukocyte level is different and is 5.5-10*9/l. General analysis blood will determine the ratio different types leukocyte fractions.

Deviations from the normative white blood cell limit may be a laboratory error. Therefore, leukocytosis or leukocytopenia is not diagnosed by a single blood test. In this case, a referral is given for another analysis to confirm the result. And only then is the issue of a course of treatment for the pathology considered.

It is important to take responsibility for your health and ask your doctor what the tests show. Approaching the critical limit of leukocyte levels is an indicator that you need to change your lifestyle and diet. Without active actions, when people do not make the right conclusions, disease comes.

Table of norms of leukocytes in the blood

How is the number of leukocytes in plasma measured?

Leukocyte cells are measured during a blood test using a special optical device - a Goryaev camera. The counting is considered automatic and provides high level accuracy (with minimal error).

The Goryaev camera determines the number of leukocytes in the blood

Optical device is a glass of special thickness in the form of a rectangle. A microscopic mesh is applied to it.

White blood cells are counted as follows:

Acetic acid, tinted with methylene blue, is poured into a glass test tube. This is a reagent into which you need to drop a little blood using a pipette for analysis. Afterwards everything is mixed well.
Wipe the glass and camera with gauze. Next, the glass is ground against the chamber until rings of different colors begin to form. The chamber is completely filled with plasma. You need to wait 60 seconds until the cell movement stops. The calculation is carried out using a special formula.

Functions of leukocytes

First of all, mention should be made of the protective function. It involves the formation immune system in specific and non-specific embodiment. The mechanism of operation of such defense involves phagocytosis.

Terms! Phagocytosis is the process of capturing hostile agents by blood cells or successfully destroying them.

The transport function of leukocytes in an adult ensures the adsorption of amino acids, enzymes and other substances, their delivery to their destination (to to the right authority along the bloodstream).
The hemostatic function in human blood has special meaning when clotting.
The definition of sanitary function is the breakdown of tissues and cells that have died due to injury, infection, and damage.

Leukocytes and their functions

The synthetic function will provide the required number of leukocytes in peripheral blood for synthesis biologically active ingredients: heparin or histamine.

If we consider the properties of leukocytes and their functional purpose in more detail, it is worth mentioning that they have specific characteristics and opportunities due to its variety.

Leukocyte composition

To understand what leukocytes are, you need to consider their types.

Neutrophil cells

Neutrophils are a common type of white blood cell, making up 50-70 percent of the total. Leukocytes of this group are produced and move in the bone marrow and are classified as phagocytes. Molecules with segmented nuclei are called mature (segmented), and those with an elongated nucleus are called rod (immature). The production of the third type of young cells occurs in the smallest volume. While there are more mature leukocytes. By determining the ratio of the volume of mature and immature leukocytes, you can find out how intense the bleeding process is. This means that significant blood loss does not allow cells to mature. And the concentration of young forms will exceed their relatives.

Lymphocytes

Lymphocyte cells have a specific ability not only to distinguish relatives from a foreign agent, but also “remember” every microbe, fungus and infection that they have ever encountered. It is lymphocytes that are the first to rush to the site of inflammation to eliminate “uninvited guests.” They build a line of defense, launching a whole chain of immune reactions to localize inflammatory tissues.

Important! Lymphocyte cells in the blood are the central link of the body’s immune system, which instantly moves to the inflammatory focus.

Eosinophils

Eosinophilic blood cells are inferior in number to neutrophils. But functionally they are similar. Their main task is to move in the direction of the lesion. They pass through blood vessels with ease and can absorb small foreign agents.

Monocytes

Monocyte cells, due to their functionality, are capable of absorbing larger particles. These are the stricken inflammatory process tissues, microorganisms and dead leukocytes that self-destructed in the process of fighting foreign agents. Monocytes do not die, but are engaged in preparing and cleaning tissues for regeneration and final restoration after an infection of an infectious, fungal or viral nature.

Monocytes

Basophils

This is the smallest group of leukocyte cells in terms of mass, which in relation to its relatives is one percent of total number. These are the cells that are like the first medical care appear where you need to instantly respond to intoxication or damage by harmful toxic substances or vapors. A striking example such a lesion is considered a bite poisonous snake or a spider.

Due to the fact that monocytes are rich in serotonin, histamine, prostaglandin and other mediators of the inflammatory and allergic process, the cells block poisons and their further spread in the body.

What does an increase in the concentration of leukocyte particles in the blood mean?

An increase in the number of white blood cells is called leukocytosis. Physiological form This condition is observed even in a healthy person. And this is not a sign of pathology. This occurs after long-term exposure to direct sun rays, due to stress and negative emotions, heavy physical exercise. In females, high white blood cells are observed during pregnancy and the menstrual cycle.

When the concentration of leukocyte cells exceeds the norm several times, you need to sound the alarm. This dangerous signal, indicating the flow pathological process. After all, the body tries to protect itself from a foreign agent by producing more defenders - leukocytes.

After making a diagnosis, the attending physician should solve one more problem - to find the root cause of the condition. After all, it is not leukocytosis that is treated, but what caused it. Once the cause of the pathology is eliminated, after a couple of days the level of leukocyte cells in the blood will return to normal on its own.

Human blood consists of liquid substance (plasma) only 55-60%, and the rest of its volume is formed elements. Perhaps their most surprising representative are leukocytes.

They are distinguished not only by the presence of a core, especially large sizes and unusual structure - the unique function assigned to this shaped element. This, as well as other features of leukocytes, will be discussed in this article.

What does a leukocyte look like and what shape does it have?

Leukocytes are spherical cells with a diameter of up to 20 microns. Their number in humans ranges from 4 to 8 thousand per 1 mm3 of blood.

It is impossible to answer the question of what color a cell is - leukocytes are transparent and are defined by most sources as colorless, although the granules of some nuclei can have a fairly wide color palette.

The variety of types of leukocytes made it impossible to unify their structure.

Segmented.
Unsegmented.

Cytoplasm:

Grainy;
Homogeneous.

In addition, the organelles that make up the cells differ.

The structural feature that unites these seemingly dissimilar elements is the ability for active movement.

Origin

The process of formation of leukocytes can be completed:

Lifespan

Each type of leukocyte has its own life expectancy.

Here is how long the cells of a healthy person live:

from 2 hours to 4 days –
from 8 days to 2 weeks – granulocytes;
from 3 days to 6 months (sometimes up to several years) – lymphocytes.

The shortest life expectancy characteristic of monocytes is due not only to their active phagocytosis, but also to the ability to give rise to other cells.

From a monocyte can develop:

The death of leukocytes can occur for two reasons:

Natural “aging” of cells, that is, the completion of their life cycle.
Cell activities associated with phagocytic processes– fight against foreign bodies.

The fight of leukocytes with a foreign body

In the first case, the function of destroying leukocytes is assigned to the liver and spleen, and sometimes to the lungs. Cell breakdown products are eliminated naturally.

The second reason is related to the course of inflammatory processes.

Leukocytes die directly "on duty" and if their removal from there is impossible or difficult, the products of cell breakdown form pus.

Video - Classification and significance of human leukocytes

The general function in which all types of leukocytes participate is - protecting the body from foreign bodies.

The task of cells is to detect and destroy them in accordance with the principle "antibody-antigen".

The destruction of unwanted organisms occurs through their absorption, while the receiving phagocyte cell significantly increases in size, perceives significant destructive loads and often dies.

The site of death of a large number of leukocytes is characterized by swelling and redness, sometimes by suppuration and increased temperature.

An analysis of its variety will help to more accurately indicate the role of a specific cell in the process of fighting for the health of the body.

Thus, granulocytes perform the following actions:

Neutrophils– capture and digest microorganisms, stimulate the development and division of cells.
Eosinophils– neutralize foreign proteins found in the body and its own dying tissues.
Basophils– promote blood clotting, regulate vascular permeability by blood cells.

The list of functions assigned to agranulocytes is more extensive:

T lymphocytes– provide cellular immunity, destroy foreign cells and pathological cells of body tissues, counteract viruses and fungi, influence the process of blood formation and control the activity of B-lymphocytes.
B lymphocytes– support humoral immunity, fight bacterial and viral infections by generating antibody proteins.
Monocytes– perform the function of the most active phagocytes, which became possible due to the large amount of cytoplasm and lysosomes (organelles responsible for intracellular digestion).

Only in the case of coordinated and harmonious work of all types of leukocytes is it possible to maintain the health of the body.

Leukocytes(white blood cells) are blood cells containing a nucleus. In some leukocytes, the cytoplasm contains granules, which is why they are called granulocytes . Others have no granularity and are classified as agranulocytes. There are three forms of granulocytes. Those of them whose granules are stained with acidic dyes (eosin) are called eosinophils . Leukocytes, the granularity of which is susceptible to basic dyes - basophils . Leukocytes, the granules of which are stained with both acidic and basic dyes, are classified as neutrophils. Agranulocytes are divided into monocytes and lymphocytes. All granulocytes and monocytes are formed in the red bone marrow, and are called myeloid cells . Lymphocytes are also formed from stem cells bone marrow, but multiply in the lymph nodes, tonsils, appendix, thymus, and intestinal lymphatic plaques. These are lymphoid cells.

Neutrophils are in vascular bed 6-8 hours, and then passes into the mucous membranes. They make up the vast majority of granulocytes. The main function of neutrophils is to destroy bacteria and various toxins. They have the ability to chemotaxis and phagocytosis. Vasoactive substances released by neutrophils allow them to penetrate the capillary wall and migrate to the site of inflammation. The movement of leukocytes towards it occurs due to the fact that T-lymphocytes and macrophages located in the inflamed tissue produce chemoattractants. These are substances that stimulate their movement towards the site. These include arachidonic acid derivatives - leukotrienes, as well as endotoxins. The engulfed bacteria enter phagocytic vacuoles, where they are exposed to oxygen ions, hydrogen peroxide, and lysosomal enzymes. Important property neutrophils is that they can exist in inflamed and edematous tissues poor in oxygen. Pus mainly consists of neutrophils and their remains. Enzymes released during the breakdown of neutrophils soften the surrounding tissues. Due to this, a purulent focus is formed - an abscess.

Basophils contained in amounts of 0-1%. They stay in the bloodstream for 12 hours. Large granules of basophils contain heparin and histamine. Due to the heparin they secrete, lipolysis of fats in the blood is accelerated. On the basophil membrane there are E-receptors to which E-globulins attach. In turn, allergens can bind to these globulins. As a result, basophils release histamine. An allergic reaction occurs - hay fever(runny nose, itchy rash on the skin, redness, bronchospasm). In addition, basophil histamine stimulates phagocytosis and has an anti-inflammatory effect. Basophils contain platelet-activating factor, which stimulates platelet aggregation and the release of platelet-derived clotting factors. Highlight heparin And histamine, they prevent the formation of blood clots in the small veins of the lungs and liver.

Lymphocytes make up 20-40% of all leukocytes. They are divided into T and B lymphocytes. The former differentiate in the thymus, the latter - in various lymph nodes. T cells are divided into several groups. Killer T cells destroy foreign antigen cells and bacteria. Helper T cells are involved in the antigen-antibody reaction. Immunological memory T cells remember the structure of the antigen and recognize it. T-amplifiers stimulate immune reactions, and T-suppressors inhibit the formation of immunoglobulins. B lymphocytes make up a minority. They produce immunoglobulins and can turn into memory cells.

Percentage various forms leukocytes are called leukocyte formula. Normally, their ratio constantly changes during diseases. Therefore, a study of the leukocyte formula is necessary for diagnosis.

Normal leukocyte formula.

Granulocytes:

Basophils 0-1%.

Eosinophils 1-5%.

Neutrophils.

Bands 1-5%.

Segmented 47-72%.

Agranulocytes.

Monocytes 2-10%.

Lymphocytes 20-40%.

Major infectious diseases are accompanied by neutrophilic leukocytosis, a decrease in the number of lymphocytes and eosinophils. If monocytosis then occurs, this indicates the body's victory over the infection. In chronic infections, lymphocytosis occurs.

Counting the total number of leukocytes produced in Goryaev's cell. Blood is drawn into a melangeur for leukocytes, and it is diluted 10 times with a 5% solution acetic acid tinted with methylene blue or gentian violet. Shake the melangeur for several minutes. During this time, acetic acid destroys red blood cells and the membrane of leukocytes, and their nuclei are stained with dye. The resulting mixture is filled into a counting chamber and leukocytes in 25 large squares are counted under a microscope. The total number of leukocytes is calculated using the formula:

X = 4000. A. i.p.

Where a is the number of leukocytes counted in squares;

b – the number of small squares in which the count was made (400);

c – blood dilution (10);

4000 is the reciprocal of the volume of liquid above the small square.

To study the leukocyte formula, a blood smear on a glass slide is dried and stained with a mixture of acidic and basic dyes. For example, according to Romanovsky-Giemsa. Then, under high magnification, the number of different forms is counted out of at least 100 counted.