Cytotoxic T cells eliminate pathogens by

Cytotoxic T cells eliminate pathogens by

releasing interleukin- 2 which stimulates other lymphocytes

releasing granzymes and perforin molecules

releasing antibodies into the bloodstream

displaying tumor antigens as part of immunological surveillance

The Correct Answer and Explanation is :

The correct answer is: Cytotoxic T cells eliminate pathogens by releasing granzymes and perforin molecules.

Explanation:

Cytotoxic T cells, also known as CD8+ T cells, are a critical part of the immune system’s response to infections and cancer. These cells specialize in recognizing and eliminating infected or abnormal cells, such as those infected with viruses or transformed into tumor cells.

Here’s a breakdown of the process:

1. Recognition: Cytotoxic T cells recognize infected or abnormal cells through the presentation of antigens (peptides derived from pathogens or tumor cells) on the surface of cells. These antigens are displayed by Major Histocompatibility Complex (MHC) Class I molecules on the surface of infected or tumor cells.
2. Activation: When a cytotoxic T cell encounters an infected or cancerous cell, it binds to the antigen-MHC I complex. This interaction activates the T cell, triggering it to release cytotoxic molecules.
3. Release of Granzymes and Perforin: The activated cytotoxic T cell releases two critical molecules—granzymes and perforin:
   • Perforin forms pores in the target cell’s membrane, allowing other molecules to enter the cell.
   • Granzymes are enzymes that enter through the pores created by perforin and initiate a cascade of events that lead to the death of the target cell through apoptosis (programmed cell death).
4. Interleukin-2 (IL-2) Release: While IL-2 is an important cytokine that stimulates the growth and activation of various immune cells, including other T cells, it is not directly involved in the cytotoxic process of eliminating target cells. Instead, IL-2 is released by Helper T cells (CD4+ T cells) to promote the proliferation of cytotoxic T cells and other lymphocytes.
5. Antibodies and Tumor Antigens: Antibodies are produced by B cells, not cytotoxic T cells, and help in targeting pathogens or infected cells for destruction. Tumor antigens are recognized by the immune system, and while cytotoxic T cells can target tumor cells based on these antigens, antibodies are typically not part of the direct cytotoxic action of T cells.

Thus, cytotoxic T cells use perforin and granzymes to directly destroy infected or cancerous cells, playing a crucial role in immunological surveillance.