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 assessment of the main lymphocyte subpopulations. The test determines the percentage distribution and absolute count of T lymphocytes, B lymphocytes, and natural killer (NK) cells in peripheral blood. The test is performed using flow cytometry, identifying cells by specific surface CD markers.

What does this test show?

This test evaluates the following cell populations:

• CD3 – general marker of T lymphocytes (all T cells);
• CD4 – helper T cells, coordinating 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 killer (NK) cells, important for antiviral and antitumor immunity.

Results are presented in two ways:

• Percentage (%) – what percentage of all lymphocytes is comprised of a specific cell population.
• 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 assess the state of the immune system or monitor its changes. The most common indications:

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

How are the results evaluated?

The obtained indices are evaluated considering the patient's age, clinical status, and other test data.

Increased or decreased counts of individual lymphocyte populations may indicate:

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

The final interpretation of the results is performed by the physician, considering the overall clinical context.