The crypt cycle. Crypt and villus production in the adult intestinal epithelium

摘要: We propose a model for the growth of individual crypts that is able to account observed changes in number cells under normal conditions, after irradiation, and 30% resection. Parameter values this are estimated both mouse man, detailed predictions crypt rates made. This does not predict steady-state size; rather it suggests grow until they bifurcate. therefore cycle (analogous cell cycle) present evidence most if all adult cycling asynchronously independently. consists four experiments indicate branching randomly distributed over intestinal epithelium, plane bifurcation oriented with respect villus base, size distribution consistent an expanding population. also report first time production epithelium. conclude populations steady state.