Quick Review Cards for Medical Laboratory Science

Cells of the Acquired Immune System Immunology Review 377

CELL

T lymphs

Helper/inducer T cells

Cytotoxic/suppressor T cells

T regulatory cells

B lymphs

Plasma cells

Memory cells

FUNCTION

Cell-mediated immunity.

Orchestrate cell-mediated immunity. Activate B

cells, cytotoxic cells, & NK cells.

Suppressor cells inhibit helper T cells. Cytotoxic

cells kill other cells.

Suppress immune response to self.

After antigenic challenge, transform into blasts

that give rise to plasma cells & memory cells.

Ab production.

Respond to ag when encountered again with

↑speed & intensity.

COMMENTS

Derived from cells in bone marrow. Develop T-cell–

specific surface ags in thymus. 60%–80% of lymphs.

CD4+. 2/3 of peripheral T cells. Normal CD4 = 1,000/μL.

In AIDS, <200/μL.

CD8+. 1/3 of peripheral T cells. (Normal CD4/CD8 ratio

2:1. In AIDS, <0.5:1).

CD4+& CD25+.

Develop in bone marrow. When mature, have surface

Igs (IgM, IgD) that act as receptors for ags. 10%–20%

of lymphs.

In peripheral lymphoid organs. Nondividing. Die in a

few days.

In peripheral lymphoid organs. Live months to years.