title: Tracking the cell hierarchy in the human intestine using biochemical signatures derived by mid-infrared microspectroscopy.
abstract: Markers of gastrointestinal (GI) stem cells remain elusive. We employed synchrotron Fourier-transform infrared (FTIR) microspectroscopy to derive mid-infrared (IR) spectra along the length of human GI crypts. Tissue sections (10-μm thick) were floated onto BaF2 windows and image maps were acquired of small intestine and large bowel crypts in transmission mode with an aperture of ≤10 μm×10 μm. Counting upwards in a step-size (≤10 μm) fashion from the crypt base, IR spectra were extracted from the image maps and each spectrum corresponding to a particular location was identified. Spectra were analyzed using principal component analysis plus linear discriminant analysis. Compared to putative crypt base columnar/Paneth cells, those assigned as label-retaining cells were chemically more similar to putative large bowel stem cells and, the small intestine transit-amplifying cells were closest to large bowel transit-amplifying cells; interestingly, the base of small intestine crypts was the most chemically-distinct. This study suggests that in the complex cell lineage of human GI crypts, chemical similarities as revealed by FTIR microspectroscopy between regions putatively assigned as stem cell, transit-amplifying and terminally-differentiated facilitates identification of cell function.
authors.affiliation: Centre for Biophotonics, Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster, UK.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Walsh
authors.forename: Azzedine
authors.initials: A
authors.lastname: Hammiche
authors.forename: Tariq G
authors.initials: TG
authors.lastname: Fellous
authors.forename: James M
authors.initials: JM
authors.lastname: Nicholson
authors.forename: Marine
authors.initials: M
authors.lastname: Cotte
authors.forename: Jean
authors.initials: J
authors.lastname: Susini
authors.forename: Nigel J
authors.initials: NJ
authors.lastname: Fullwood
authors.forename: Pierre L
authors.initials: PL
authors.lastname: Martin-Hirsch
authors.forename: Malcolm R
authors.initials: MR
authors.lastname: Alison
authors.forename: Francis L
authors.initials: FL
authors.lastname: Martin
mesh_terms: D004247:DNA / Q000737:chemistry; D016002:Discriminant Analysis; D006801:Humans; D007420:Intestine, Large / Q000737:chemistry / Q000166:cytology*; D007421:Intestine, Small / Q000737:chemistry / Q000166:cytology*; D008954:Models, Biological; D025341:Principal Component Analysis; D012313:RNA / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013234:Stem Cells / Q000737:chemistry / Q000166:cytology; D017356:Synchrotrons
chemical_list: D012313:RNA; D004247:DNA