Effector cell

Activated cells that execute a specific immune response.

On the one hand, this refers to T cells that have previously been sensitized by an antigen and then have a cytotoxic effect on the target cell containing the antigen.

For example, the tumor cells of mycosis fungoides are identified as CD4+ skin-resident effector memory T cells (Trm cells) of clonal origin. They are part of the local immune defense of the skin, are long-lived and stably committed to their home tissue, which makes the often decades-long exclusive skin infestation plausible (DeSimone JA et al. 2015).

For B cells, the antibody-forming plasma cells or the antibodies themselves are the effectors.

Natural killer cells(NK cells) recognize or destroy degenerated or infected cells without prior sensitization.

1. DeSimone JA et al. (2015) Recent advances in primary cutaneous T-cell lymphoma. Curr Opin Oncol 27:128-33.