T-lymphocytes-helpers( CD4) in the blood

Normally, the relative number of T-lymphocyte helper cells in the blood in adults is 36-55%, the absolute amount is 0.4-1.1x109 / l.

T-lymphocytes-helpers - inducers of the immune response, regulate the strength of the immune response to foreign Ag and control the constancy of the internal environment of the body( antigenic homeostasis).An increase in the number of T-lymphocyte-helpers indicates a hyperactivity of immunity, a decrease in immunological failure.

The ratio of T-helpers and T-suppressors in the peripheral blood is the leading factor in assessing the state of the immune system, since the intensity of the immune response depends on this. In the norm of cytotoxic cells and AT should be produced as much as necessary for the removal of one or another Ar. Insufficient activity of T-suppressors leads to the predominance of the influence of T-helpers, which contributes to a stronger immune response( pronounced antibody production and / or prolonged activation of T-effectors).Excessive activity of T-suppressors, on the contrary, leads to rapid suppression and abortive course of the immune response and even to the phenomena of immunological tolerance( immunological response to Arg does not develop).With a strong immune response, the development of autoimmune and allergic processes is possible. High functional activity of T-suppressors does not allow the development of an adequate immune response, and therefore the clinical picture of immunodeficiency is dominated by infection and predisposition to malignant growth. The value of the CD4 / CD8 index of 1.5-2.5 corresponds to the normal state;more than 2.5 - hyperactivity;less than 1 - immunodeficiency. In severe inflammation, the CD4 / CD8 ratio may be less than 1. This ratio is of fundamental importance in assessing the immune system in patients with HIV infection. HIV selectively affects and destroys CD4-lymphocytes, resulting in a decrease in the CD4 / CD8 ratio to values ​​significantly less than 1.

An increase in the CD4 / CD8 ratio( up to 3) is often noted in the acute phase of various inflammatory diseases, by increasing the number of T-helpersand decrease in T-suppressors. In the middle of the inflammatory disease, a slow decrease in the content of T-helpers and an increase in T suppressors are noted. When the inflammatory process subsides, these indicators and their ratios are normalized. An increase in the CD4 / CD8 ratio is characteristic of virtually all autoimmune diseases: hemolytic anemia, immune thrombocytopenia, Hashi moto thyroiditis, pernicious anemia, Goodpasture syndrome, SLE, rheumatoid arthritis. An increase in the ratio of CD4 / CD8 due to a decrease in the number of CD8-lymphocytes in these diseases is usually detected with exacerbation and high activity of the process. A decrease in the CD4 / CD8 ratio due to an increase in the number of CD8-lymphocytes is characteristic of a number of tumors, in particular Kaposi's sarcoma. Diseases and conditions leading to a change in the number of CD4-lymphocytes in the blood are presented in the table.

Table Diseases and conditions that lead to a change in the amount of CD4 in the blood

Table Diseases and conditions that lead to changes in the amount of CD4 in the blood