Cytotoxic T lymphocytes, a crucial component of the immune system, are primarily known by a specific surface marker. Based on the provided reference, cytotoxic T-cells are also identified as CD8+ T-cells.
These T-cells play a vital role in identifying and eliminating infected cells or cancer cells.
Understanding Cytotoxic T Lymphocytes
T-lymphocytes, or T-cells, are a type of white blood cell critical for cell-mediated immunity. According to the reference, there are two main classes of T-lymphocytes:
- Helper T-cells (also known as CD4+ T-cells)
- Cytotoxic T-cells (also known as CD8+ T-cells)
The reference states: "There are two classes of T-lymphocytes, helper and cytotoxic T-cells, also called CD4+ and CD8+ T-cells, respectively." This highlights that cytotoxic T lymphocytes are characterized by the presence of the CD8 protein on their surface, hence the name CD8+ T-cells.
The Role of CD8+ T-cells
CD8+ T-cells are the 'killers' of the adaptive immune system. Their main functions include:
- Recognizing Infected Cells: They identify cells displaying fragments of viral or bacterial proteins on their surface via MHC class I molecules.
- Destroying Target Cells: Upon recognition, they release cytotoxic molecules (like perforin and granzymes) that induce programmed cell death (apoptosis) in the infected or cancerous cell, effectively eliminating the threat.
While the reference focuses on their classification as CD8+ T-cells within the broader T-lymphocyte classes, this marker is the primary way they are distinguished and referred to in immunology.
