Chapter 18 Organ Culture of the Mucosa of Human Small Intestine

Abstract

The chapter discusses the methods and applications of organ culture of the mucosa of human small intestine. The mucosa of the small intestine is a complex and highly polarized tissue with its villi lined primarily by mature absorptive cells and mucus-secreting goblet cells and its crypts lined by proliferating undifferentiated cells and differentiated secretory cells, which include Paneth, goblet, and endocrine cells. Fragments of intestinal mucosa such as human peroral intestinal biopsies, and everted sacs or rings of intestine from laboratory mammals immersed in oxygenated buffers or media are useful for short-term in vitro studies. However, careful morphological examination shows that epithelial cell necrosis and degeneration occurs rapidly in such systems, generally within 0.5 to 3 hours. During organ culture, the relationships of epithelial cells to one another and to their underlying mesenchyme are preserved. As with other in vitro systems, the environment of the tissues under study can be controlled more precisely than when in vivo preparations are used as exposure to the normal intestinal luminal contents, circulating humoral factors, and neurogenic stimuli are largely eliminated. The application of organ culture methodology to the maintenance in vitro of mucosal biopsies from the small intestine of humans and experimental animals permits study of intestinal mucosal synthetic, secretory, and epithelial cell proliferative function for at least 24 to 48 hours.