Self-antigens

Definition

Self-antigens are molecules or molecular structures naturally present within an individual's own body that are recognized by the immune system. They play a crucial role in distinguishing self from non-self, preventing autoimmune responses.

5 Must Know Facts For Your Next Test

1. Self-antigens are typically presented on cell surfaces by Major Histocompatibility Complex (MHC) molecules.
2. T cells undergo negative selection in the thymus to eliminate those that strongly react to self-antigens.
3. Failure to properly recognize self-antigens can lead to autoimmune diseases.
4. Autoantibodies are antibodies produced against self-antigens and are markers of autoimmune disorders.
5. Self-tolerance is the immune system's ability to avoid attacking self-antigens.

Review Questions

• What role do self-antigens play in preventing autoimmune responses?
• How does the immune system ensure T cells do not react strongly to self-antigens?
• What might be the consequence of a failure in recognizing self-antigens?

Related terms

Major Histocompatibility Complex (MHC): A set of cell surface proteins essential for the acquired immune system to recognize foreign molecules.

Antigen-Presenting Cells (APCs): Cells such as dendritic cells, macrophages, and B cells that process and present antigens for recognition by T cells.

Autoimmune Disease: A condition arising from an abnormal immune response against substances and tissues normally present in the body.