Confocal images of immunofluorescence staining on E18.5 wild-type or Nkx2.2–/–; Nkx2.2hdEnR islets. (A-D) Co-expression of insulin (red) with Nkx6.1 (green; A,B) or Pdx1 (green; C,D). (E-H) MafA and Glut2 (green) are co-expressed with insulin-positive (red) cells in wild-type (E,G) islets, but neither is co-expressed with rescued insulin-positive cells (F,H). Inset in F shows a rare insulin-positive cell co-expressing MafA. (I,J) Glucagon (red) and Glut2 (green) immunostaining. No Glut2-positive cells are found in Nkx2.2–/–; 2.2hdEnR islets (H,J; 40× magnification).