Segment-neutron neutrophils are our defenders
In the general analysis of blood, the leukocyte formula, that is, the percentage of different classes of leukocytes in the blood, is calculated. The majority of leukocytes in an adult in the formula are segmented neutrophils( about 70%).They are their main part.
Leukocytes are divided into two main series: granulocytes( granular) and agranulocytes( without granularity).Granulocytes in turn are divided into neutrophils, eosinophils and basophils. Each cell species has a specific granularity in the cytoplasm and performs its special functions.
All granulocyte cells in their development undergo developmental stages from the myeloblast, through a series of intermediate immature cells, to the stab and segmented leukocytes. This applies to all three types of granulocytes - to neutrophils, eosinophils and basophils. In the peripheral blood, normally only neutrophils can be found that are stabnoid and segment-nuclear. The younger cells enter the blood from the bone marrow only in case of serious diseases.
The stab and segmented neutrophils differ in the form of the cell nucleus. The first nucleus is flat, similar to a curved rod. The second nucleus is divided by special constrictions into several( 2-4) segments. The cytoplasm of cells is colored pink. It has a fine grain of brown color. With infectious diseases, the neutrophil granularity becomes larger and blue( the so-called toxigenic granularity).This is one of the signs of the inflammatory process.
The function performed by the stab and segmented neutrophils in the body is to protect against foreign particles, viruses, fungi and bacteria. Granulocytes have phagocytic activity. Their granules contain a specific enzyme myeloperoxidase, it enhances the effect of antibacterial substances. Neutrophils can actively move into the focus of inflammation.
The ratio of segmented neutrophils and other cells in the leukocyte formula corresponds to the age norms. Thus, in children under 5 years of age, lymphocytes predominate, and neutrophils do not have more than 30%.The number of stab neutrophils is normally 1-6%.An increase in the number of neutrophils accompanies various diseases and is called neutrophilia.
Usually, neutrophilia accompanies a general increase in the number of leukocytes. In this case, the neutrophils of the stab stem are also elevated. Sometimes in the blood for serious diseases appear immature cells - metamyelocytes( juveniles) and myelocytes. An increase in the number of stab cells, the appearance of metamyelocytes and myelocytes is called a shift of the leukocyte formula to the left. Often the shift of the formula is combined with the appearance of toxigenic granularity in the stabnoid and segmented neutrophils and the basophilia of their cytoplasm.
Such changes in neutrophils accompany acute inflammatory diseases, shock conditions, heart attack, various intoxications. The shift of the formula to the left is particularly pronounced in chronic myelocytic leukemia. In this disease segmental neutrophils sharply decrease in both percentage and absolute ratio. The formula is dominated by stab and immature cells. Reducing the number of segmented neutrophils leads to the fact that the protective function of leukocytes decreases. This threatens the accession of various infections.
Reduction of segmented nuclear as well as stab neutrophils is called neutropenia. It is usually observed against a background of a general decrease in leukocytes. This condition occurs in chronic and viral infections, often after taking cytostatics, after radiation therapy, with blood diseases such as agranulocytosis or aplastic anemia.
Thus, the role of segmented neutrophils lies in protecting a person from infections. In diseases, the number of them increases. This is expressed in a change in the ratio of cells in the blood formula.