12-Cell Mediated Effector Responses Chpt. 14 2023 (5)

Cell-mediated immune response

An immune response that is effective against virus-infected cells, tumor cells, grafted tissues, fungi, intracellular parasites, and some slow-growing intracellular bacteria.

CD45

A large transmembrane cell surface molecule expressed by all leukocytes that plays a crucial role in TCR signaling and T cell activation.

Effector T cells

Activated T cells that can respond quickly to antigen stimulation with minimal co-stimulation, characterized by increased adhesion molecules.

TCR signaling

The initial steps in T cell activation that involve the engagement of T Cell Receptor (TCR) with antigen presented by MHC molecules.

Cytotoxic T lymphocytes (CTLs)

A subtype of T cells that directly kill infected or cancerous cells by releasing perforin and granzymes.

Perforin

A protein released by cytotoxic T cells that forms pores in target cell membranes, facilitating the entry of granzymes.

Granzymes

Serine proteases released by cytotoxic T cells that enter target cells through perforin pores and initiate apoptosis.

Immunological synapse

The focal point of interaction between T cells and antigen-presenting cells that is essential for T cell activation.

Natural Killer (NK) Cells

A type of lymphocyte that can kill infected or tumor cells without the requirement for specific antigen recognition.

Fas/FasL interaction

A mechanism of inducing apoptosis via the binding of Fas ligand on cytotoxic T cells to the Fas receptor on target cells.