Pronunciation: klas switch
Definition: Before activation, a B cell may only produce antigen-specific IgM but after appropriate immunomodulatory signals, the B cell may class switch and produce other antibody isotypes, such as IgA and IgG. All antibodies produced from the same clone will have the same antigen specificity, even though the immunoglobulin isotypes may be different.
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Examples: glitazone, GI cocktail, etc.