key term - Class switching

Definition

Class switching is a biological mechanism in which a B cell changes the class of antibody it produces without altering the specificity for antigen. This process involves recombination at the DNA level to switch from one immunoglobulin (Ig) class to another, such as from IgM to IgG.

5 Must Know Facts For Your Next Test

1. Class switching allows the immune system to produce different classes of antibodies that are better suited for specific functions and locations in the body.
2. The process of class switching is guided by cytokines released by T helper cells, which influence which antibody class will be produced.
3. Class switch recombination (CSR) occurs in activated B cells within germinal centers of lymphoid tissues.
4. Switch regions, located upstream of constant region genes in the immunoglobulin heavy chain locus, play a critical role in facilitating class switching.
5. Activation-induced cytidine deaminase (AID) is an enzyme essential for initiating the DNA breakage and repair process required for class switching.

Review Questions

Related terms

B Lymphocytes:

White blood cells that mature in bone marrow and produce antibodies.

Immunoglobulins:

Proteins produced by B cells that act as antibodies to neutralize pathogens.

Germinal Centers:

Sites within secondary lymphoid organs where mature B cells proliferate, differentiate, and undergo somatic hypermutation and class switch recombination.