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. © 2009 Elsevier B.V. All rights reserved.
Walsh, M. J., Hammiche, A., Fellous, T. G., Nicholson, J. M., Cotte, M., Susini, J., … Martin, F. L. (2009). Tracking the cell hierarchy in the human intestine using biochemical signatures derived by mid-infrared microspectroscopy. Stem Cell Research, 3(1), 15–27. https://doi.org/10.1016/j.scr.2009.02.003