Abstrakt: |
OBJECTIVES:: Bowel segments distal to a congenital intestinal obstruction have been suggested to be immature. In other words, luminal components such as amniotic fluid (before birth) and/or enteral nutrition (after birth) may be required to activate intestinal epithelial protein expression, thereby influencing epithelial differentiation. We investigated cell-type–specific protein expression proximal and distal to jejunal and ileal atresias in human newborns.PATIENTS AND METHODS:: We immunohistochemically studied intestinal tissue specimens of 16 newborns who had undergone surgery for jejunal or ileal atresia. Sections were taken from both the proximal and distal sides of the atresias.RESULTS:: For all patients, the enterocyte-specific markers lactase, sucrase-isomaltase, sodium glucose cotransporter 1, glucose transporters 2 and 5, intestinal fatty acid–binding protein and alkaline phosphatase were expressed at a mean 3 ± 1 days after birth, both proximal and distal to jejunal and ileal atresias. Expression of goblet cell–specific markers mucin 2 and trefoil factor 3 and that of the Paneth cell marker lysozyme was maintained at either side of the atretic segment.CONCLUSIONS:: With respect to the markers used, the human small intestinal epithelium is already differentiated shortly after birth. The absence of intestinal continuity in case of a jejunal or ileal atresia does not affect epithelial protein expression. This would seem to indicate that the developing small intestinal epithelium matures independently of luminal components. [ABSTRACT FROM AUTHOR] |