... a consequence of increased cell production. There must be a level of control that determines whether new cells will feed SPU multiplication or increased cell turnover. The nature of this control remains entirely mysterious. One possibility that has been suggested for small intestinal crypts is that the crucial...

... and maturation leads us to formulate a spiral model of cell and tissue organisation . This concept is illustrated for the intestinal epithelium. It is concluded that the small intestinal crypts contain 4–16 actual stem cells in steady state but up to 30–40 potential stem cells (clonogenic cells) which may take...

.... Morph . 87 , 229 – 239 . Ponder , B. A. J. , Schmidt , G. H. , Wilkinson , M. M. , Wood , M. J. , Monk , M. & Reid , A. ( 1985b ). Derivation of mouse intestinal crypts from single progenitor cells . Nature 313 , 689 – 691 . 10.1038/313689a0 Ponder...

...Günter H. Schmidt; David J. Garbutt; Maureen M. Wilkinson; Bruce A. J. Ponder ABSTRACT The epithelium of each individual intestinal crypt in adult mouse aggregation chimaeras is composed of cells of a single parental genotype ( Ponder et al . 1985 ). Using a carbohydrate polymorphism recognized...