What is the process of isotype switching?

1. the CD40L-CD40 interaction of the T and B cells and the cytokines that are produced induce activation-induced deaminase (AID) 2. AID converts cytosines into uracils in the switch regions 3. this causes double-stranded DNA breaks, which causes deletion of the DNA 4. RNA splicing causes the VDJ region to be spliced right next to the exon that is needed for the immunoglobulin, e.g. IgG