Epitopes

Definition

Epitopes are specific regions on an antigen that are recognized and bound by antibodies or T-cell receptors. They play a crucial role in the specificity of the immune response.

5 Must Know Facts For Your Next Test

1. Epitopes are also known as antigenic determinants.
2. A single antigen can have multiple epitopes, each capable of eliciting a different immune response.
3. B cells recognize epitopes through their surface immunoglobulins (antibodies), while T cells recognize them via T-cell receptors in conjunction with MHC molecules.
4. The binding of an epitope to its corresponding antibody is highly specific, much like a lock and key mechanism.
5. Linear epitopes consist of sequential amino acids, whereas conformational epitopes depend on the protein's three-dimensional structure.

Review Questions

• What is an epitope and why is it important for the immune response?
• How do B cells and T cells differ in their recognition of epitopes?
• Explain the difference between linear and conformational epitopes.

Related terms

Antigen:

A substance that induces an immune response, typically by being recognized by antibodies or T-cell receptors.

Antibody:

A protein produced by B cells that specifically binds to antigens or epitopes to neutralize them.

Major Histocompatibility Complex (MHC):

Molecules on cell surfaces that present peptide fragments (epitopes) for recognition by T-cells.