CD3, CD4, CD8, CD19 and CD16+56 determination (percentage and absolute cell count x109 /l)

This is a comprehensive immunological blood test designed for the quantitative evaluation of major lymphocyte subpopulations. The test determines the percentage distribution and absolute count of T lymphocytes, B lymphocytes, and natural killer (NK) cells in peripheral blood. It is performed using the flow cytometry method, identifying cells by specific surface CD markers.

What does this test show?

The test evaluates the following cell populations:

• CD3 – general T lymphocyte marker (all T cells);
• CD4 – T helper cells, which coordinate the immune response;
• CD8 – cytotoxic T cells responsible for destroying virus-infected or altered cells;
• CD19 – B lymphocytes involved in antibody production;
• CD16+56 – natural killers (NK cells), important for antiviral and antitumor immunity.

Results are presented in two ways:

• Percentage (%) – what percentage of all lymphocytes a specific cell population constitutes.
• Absolute count (x10⁹/L) – the actual number of cells per unit volume of blood.

When is the test recommended?

The test is performed when it is necessary to evaluate the condition of the immune system or to monitor its changes. The most common indications are:

• suspected primary or secondary immunodeficiencies;
• frequent recurring or severe infections;
• autoimmune diseases;
• monitoring of immunosuppressive therapy;
• status post organ or bone marrow transplantation;
• diagnostics and monitoring of certain hematological or oncological diseases.

How are the results evaluated?

The obtained indicators are evaluated taking into account the patient's age, clinical condition, and data from other tests.

Increased or decreased numbers of individual lymphocyte populations may indicate:

• activation or suppression of the immune system,
• acute or chronic infections,
• autoimmune processes,
• hematological diseases,
• immunosuppressive effects.

The final interpretation of the results is performed by a physician, taking into account the overall clinical context.