An alternative name for CD4 T cells or T helper cell.

A T-lymphocyte that binds antigens on the surface of presenting cells and secretes lymphokines that activate cytotoxic cells.

a functional subclass of T cells which can help to create cytotoxic T cells and cooperate with B cells to produce an antibody response. They usually recognize antigens in association with class 2 major histocompatibility complex (MHC) molecules.

T cell with CD4 receptor that recognizes antigens on the surface of a virus-infected cell and secretes lymphokines that stimulate B cells and killer T cells; helper T cells are infected and killed by the AIDS virus

A subset of T cells that carry the T4 marker and are essential for turning on antibody production, activating cytotoxic T cells, and initiating other immune responses. The number of T4 cells in a blood sample is used to measure the health of the immune system in people with HIV.