Growth of crypt cell nodules in duodenal mucosa in man during organ culture in vitro.

Culture of peroral biopsy specimens from duodenal mucosa in vitro for 22 hours using a basic culture medium resulted in the formation of crypt cell nodules. The addition of collagen and serotonin to the culture medium increased the occurrence of the nodules and, invariably, their size. The nodules were situated on the pericryptal basement membrane and contained cells that resembled columnar cells, goblet cells, and endocrine cells. The overall nodular structure suggested that they had been formed by the stimulation of stem cell division at the crypt base, but the factors responsible for this have not as yet been identified. The growth of these nodules may offer opportunities for studying stem cell division and differentiation in small intestinal mucosa in man.