Altered tryptophan hydroxylase 2 expression in enteric serotonergic nerves in Hirschsprung’s-associated enterocolitis

Figure 2 Confocal micrograph series demonstrating tryptophan hydroxylase-2 expression pattern in the submucosal plexus. Again, no HuD expression is seen in the aganglionic bowel, although there are some TPH2 immuno-positive fibres seen in (A). In ganglionic bowel in HSCR (B), TPH2 co-expressed with HuD (white arrow) in ganglion cells. There was co-expression of TPH2 with anoctamin (ANO)-positive submucosal interstitial cells of Cajals (ICCs) and PDGFRα⁺ cells, seen in (C) and (D) respectively (white arrow). TPH2: Tryptophan hydroxylase-2; HSCR: Hirschsprung’s disease.