Normal T Cell Levels

Normal T-cell levels vary according to the type of T cell. There are three different kinds: helper, cytotoxic and regulatory. T cells are a type of white blood cell called a lymphocyte. Lymphocytes comprise 10 to 45 percent of our white blood cells.

Helper

• Normal levels of helper T cells (also called CD4 T cells) are 500 to 1500 milliunits per milliliter. Helper cells are first responders. They recognize when infection is present and tell fighter cells.

Cytotoxic

• Normal levels of cytotoxic cells measure 300 to 800 milliunits per milliliter. Cytotoxic, or CD8 T cells, are chiefly responsible for killing viruses.

Regulatory

• These specialized lymphocytes tell the immune system when to stop fighting. They are a subset of CD4 T cells, according to the Merck Manual.

High Levels

• When blood tests show T-cell levels are elevated, it can indicate one of many diseases. High T-cell levels may be a sign of acute lymphocytic leukemia, mononucleosis or multiple myeloma, according to the National Institutes of Health.

Low Levels

• If T cells have dropped below the normal range, it may indicate the presence of Hodgkin̵7;s Disease, an acute viral infection or AIDS. When diagnosing AIDS, particular attention is paid to the amount of helper T cells.