Histochemical studies of mucosubstances and lipids in normal human oesophageal epithelium

Abstract

The histochemistry of lipids and mucosubstances in normal human oesophageal epithelium were studied in biopsies obtained from 24 patients undergoing investigations of the upper gastro-intestinal tract. Neutral fat droplets, 1-2 mum in diameter, were present in all layers, the greatest number being in the functional layer cells. No unsaturated lipids or fatty acids were demonstrable. Much glycogen was present in the cytoplasm of the prickle and functional cell layers as demonstrated by PAS (and diastase digestion) techniques. The intercellular space of the most superficial of the functional cell layer contained neutral and sialic acid-rich acid mucopolysaccharides. These may be important in protecting the epithelium against physical and chemical trauma.

Characterizing variability in in vivo Raman spectra of different anatomical locations in the upper gastrointestinal tract toward cancer detection

“…This optical filtering effect has also been observed in autofluorescence spectroscopy of gastric and esophageal neoplastic tissues as a result of the increased epithelial proliferation. 23,24,42 It is particularly interesting that we observed inverse linear relationship (correlation coefficient R > 0.92) between collagen and triolein in the esophagus, suggesting that the large interpatient variation in the lipids signals could be connected with epithelial properties (e.g., thickness, lipid content) 40,41 within the esophagus. To further evaluate the clinical implications of interorgan variability, we also employed a powerful classification algorithm [e.g., partial least squares-discriminant analysis (PLS-DA)] 25 to exploit subtle spectral variations of the entire Raman spectra that are not resolved by biomolecular modeling.…”

“…The biochemical modeling indicates a considerably elevated content in lipids of the distal esophagus as compared to the gastric cardia (p = 3.2×10 −6 ), which is in agreement with the reports on accumulations of lipids in the dense cell layers of the esophageal epithelium, as a part of the mucosal barrier. 40,41 Further, the relative less collagen of the esophagus compared to gastric is also linked with the thick squamous epithelium obscuring the Raman signal from the extensive connective tissues in the lamina propria. This optical filtering effect has also been observed in autofluorescence spectroscopy of gastric and esophageal neoplastic tissues as a result of the increased epithelial proliferation.…”

Changes in enzyme activity in normal and histologically inflamed oesophageal epithelium.

“…Glycogen, which is absent only from the basal cells (Hopwood et al, 1977), was demonstrated by the PAS technique (Pearse, 1968). This technique usefully divides the epithelium into two compartments which may then be assessed histochemically.…”

How Does the Esophageal Epithelium Maintain Its Integrity?

“…5) [7]. Similar glycoconjugates have been found within the inter cellular spaces of the human esophagus [9]. Although tight junctions are extremely important in other tissues, studies suggest that they may be less important in esophagus [7], However, being the most narrow region between adjacent cells, tight junctions may help retain the presumed largersized giycoconjugate material within the intercellular space.…”