Immune tolerance

Immune tolerance is a state of unresponsiveness of the immune system to substances or tissue that have the capacity to elicit an immune response in a given organism. It is induced by prior exposure to that specific antigen and contrasts with conventional immune-mediated elimination of foreign antigens.

Mechanisms of Immune Tolerance

Immune tolerance involves various mechanisms, including clonal deletion, clonal anergy, and immune suppression.

• Clonal Deletion: This is the removal of B cells and T cells that react with self-antigens during their development. This process occurs in the bone marrow for B cells and in the thymus for T cells.

• Clonal Anergy: This is a state of functional inactivity induced in mature lymphocytes that encounter self-antigens in the absence of the co-stimulatory signals that are required for their activation.

• Immune Suppression: This involves the action of regulatory T cells that suppress the immune response against self-antigens.

Clinical Significance

Immune tolerance is crucial for preventing autoimmune diseases, which occur when the immune system mistakenly attacks the body's own cells. However, immune tolerance can also be a problem in certain situations, such as cancer, where the immune system tolerates cancer cells instead of destroying them.

See Also

• Autoimmune disease
• Immunology
• Regulatory T cell
• Clonal deletion
• Clonal anergy

References

Immune tolerance Resources
Latest articles Most recent articles Ongoing trials	Wikipedia