The Role of Cytotoxic T Cells in Immune Responses: Activation and Function Explained

Active cytotoxic T cells (seeks out and destroy antigen- displaying cells that initiated the immune responses) memory cytotoxic T cells (prevents the cellular responses from being too strong or too long lasting)

Cytotoxic T cells, also known as killer T cells, are a type of white blood cell that play a crucial role in the immune responses against viral-infected cells and cancer cells

Cytotoxic T cells, also known as killer T cells, are a type of white blood cell that play a crucial role in the immune responses against viral-infected cells and cancer cells. These cells can recognize and eliminate specific target cells presenting antigens on their surface.

Active cytotoxic T cells are T cells that have been activated by the presence of antigens on the surface of infected or aberrant cells. How do these T cells become activated? Firstly, a macrophage or dendritic cell engulfs and processes the foreign antigen. The processed antigen is then presented on the surface of the antigen-presenting cell (APC) along with major histocompatibility complex (MHC) molecules. When the active cytotoxic T cell encounters this complex of antigen and MHC molecules that matches its specific receptor on its surface, it becomes stimulated and triggers an immune response.

Once activated, active cytotoxic T cells will proliferate and differentiate to become effector cells. These effector cells secrete toxic substances, such as perforin and granzyme, which are released near the target cell to induce its destruction. Perforin creates pores on the surface of the target cell, allowing granzyme to enter and initiate programmed cell death, or apoptosis. This process ensures the elimination of the infected or aberrant cell.

Memory cytotoxic T cells, on the other hand, are a subset of long-lived T cells that remain after a primary immune response to an infection or vaccination. These memory cells play a critical role in providing long-term immunity against subsequent exposures to the same antigen.

The memory cytotoxic T cells have a slightly different role compared to active cytotoxic T cells. They aim to prevent the immune response from being too strong or too long-lasting. Upon subsequent encounters with the same antigen, memory cytotoxic T cells can rapidly recognize and respond to the antigen, leading to a faster and more efficient immune response. This results in a quicker activation and proliferation of active cytotoxic T cells, leading to a faster elimination of infected or aberrant cells.

Overall, active cytotoxic T cells are the front-line immune responders that seek out and destroy antigen-presenting cells, whereas memory cytotoxic T cells provide a rapid and specific response upon re-exposure to the antigen, ensuring a quicker and more effective immune response against the pathogen or cancer cells.

More Answers: