Types of Activated T-Cells

Summary

After binding to antigens, T-cells are activated as one of three different cell types: helper, cytotoxic, and memory T-cells. Helper T-cells help coordinate the immune response by activating other cell types, like B-cells, cytotoxic T-cells, and the general responders of the innate immune system. Cytotoxic T-cells directly kill pathogens or infected cells by releasing perforin. Finally, memory T-cells retain information about the pathogen so our system can coordinate a stronger secondary response in the case of another infection by the same pathogen.

Key Points

• Types of Activated T-cells
  • Activation (antigen-binding) produces 3 types of mature T cells
    • Helper T cells 
      • “Help” the immune response by activating other cells and coordinating a response
        • activates B cells, cytotoxic cells, and other immune cells (e.g. macrophages) 
    • Cytotoxic/killer T cells 
      • Directly kill pathogens/infected cells by releasing perforin, a protein which punctures the antigen-carrying cell
    • Memory T cells
      • Store information (memory) about specific pathogen to prepare for secondary response 
    • T regulatory cells: help reduce autoimmune diseases by distinguishing b/w self and nonself molecules