Radical reversal of vasoactive intestinal peptide (VIP) receptors during early lymphopoiesis

► VPAC1 is the exclusive, full-length VIP receptor expressed in early thymocyte progenitors (ETP). ► VPAC1 and VPAC2 undergo a transitory reversal in expression during thymocyte development. ► The transcription factor, Ikaros, may play a role in VPAC1 and VPAC2 reversal. ► VPAC2 knockout mouse and wild type controls show similar DN percentages. ► VIP signaling may contribute to thymocyte movement and/or protect thymocytes from cell death during early lymphopoiesis.