title: Heterogeneity in histone 2B-green fluorescent protein-retaining putative small intestinal stem cells at cell position 4 and their absence in the colon.
abstract: Stem cells have been identified in two locations in small intestinal crypts; those intercalated between Paneth cells and another population (which retains DNA label) are located above the Paneth cell zone, at cell position 4. Because of disadvantages associated with the use of DNA label, doxycycline-induced transient transgenic expression of histone 2B (H2B)-green fluorescent protein (GFP) was investigated. H2B-GFP-retaining putative stem cells were consistently seen, with a peak at cell position 4, over chase periods of up to 112 days. After a 28-day chase, a subpopulation of the H2B-GFP-retaining cells was cycling, but the slow cycling status of the majority was illustrated by lack of expression of pHistone H3 and Ki67. Although some H2B-GFP-retaining cells were sensitive to low-dose radiation, the majority was resistant to low- and high-dose radiation-induced cell death, and a proportion of the surviving cells proliferated during subsequent epithelial regeneration. Long-term retention of H2B-GFP in a subpopulation of small intestinal Paneth cells was also seen, implying that they are long lived. In contrast to the small intestine, H2B-GFP-retaining epithelial cells were not seen in the colon from 28-day chase onward. This implies important differences in stem cell function between these two regions of the gastrointestinal tract, which may have implications for region-specific susceptibility to diseases (such as cancer and ulcerative colitis), in which epithelial stem cells and their progeny are involved.
authors.affiliation: Institute of Infection, Immunity and Inflammation, C Floor, West Block, Queen's Medical Centre, Nottingham, NG7 2UH, UK.
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Hughes
authors.forename: Ricardo M C
authors.initials: RM
authors.lastname: Gândara
authors.forename: Tanvi
authors.initials: T
authors.lastname: Javkar
authors.forename: Fred
authors.initials: F
authors.lastname: Sablitzky
authors.forename: Hanno
authors.initials: H
authors.lastname: Hock
authors.forename: Christopher S
authors.initials: CS
authors.lastname: Potten
authors.forename: Yashwant R
authors.initials: YR
authors.lastname: Mahida
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D003106:Colon / Q000166:cytology*; D004247:DNA / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006657:Histones; D007421:Intestine, Small / Q000166:cytology* / Q000528:radiation effects; D051379:Mice; D019879:Paneth Cells / Q000378:metabolism*; D011993:Recombinant Fusion Proteins; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000528:radiation effects
chemical_list: D006657:Histones; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins; D004247:DNA