🦠microbiology review

Activation of cytotoxic T cells

Written by the Fiveable Content Team • Last updated August 2025
Written by the Fiveable Content Team • Last updated August 2025

Definition

Activation of cytotoxic T cells involves the recognition of antigens presented by infected or abnormal cells, followed by the proliferation and differentiation into effector cells capable of inducing apoptosis in target cells.

Course connection

Topic 18.1: 18.1 Overview of Specific Adaptive Immunity

Unit 18

5 Must Know Facts For Your Next Test

  1. Cytotoxic T cells, also known as CD8+ T cells, require antigen presentation by MHC class I molecules to become activated.
  2. The activation process is facilitated by antigen-presenting cells (APCs) such as dendritic cells that provide necessary co-stimulatory signals.
  3. Interleukin-2 (IL-2) plays a crucial role in promoting the proliferation and differentiation of activated cytotoxic T cells.
  4. Once activated, cytotoxic T cells release perforin and granzymes to induce apoptosis in infected or abnormal target cells.
  5. Memory cytotoxic T cells are generated after initial activation and provide faster responses upon subsequent exposures to the same antigen.