Premium
High‐Resolution Analysis of Barrier Function
Author(s) -
Fromm Michael,
Krug Susanne M.,
Zeissig Sebastian,
Richter Jan F.,
Rosenthal Rita,
Schulzke JörgDieter,
Günzel Dorothee
Publication year - 2009
Publication title -
annals of the new york academy of sciences
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.712
H-Index - 248
eISSN - 1749-6632
pISSN - 0077-8923
DOI - 10.1111/j.1749-6632.2009.04047.x
Subject(s) - paracellular transport , barrier function , occludin , tight junction , spectroscopy , conductance , dielectric spectroscopy , resolution (logic) , chemistry , confocal , biophysics , sigmoid function , optics , biological system , materials science , biology , physics , permeability (electromagnetism) , computer science , microbiology and biotechnology , membrane , biochemistry , electrode , quantum mechanics , condensed matter physics , electrochemistry , artificial intelligence , artificial neural network , machine learning
High‐resolution analysis of epithelial barrier function adds substantial information to that provided by conventional transepithelial electrical resistance (TER) measurements. This chapter describes three high‐resolution techniques. First, two variants of impedance spectroscopy are delineated. One‐path impedance spectroscopy discriminates vertically between serial pathways, namely resistances of the epithelial cell layer and of subepithelial tissues. As a typical application, measurements on human sigmoid colon biopsies from patients suffering from Crohn's disease are reported. Two‐path impedance spectroscopy allows to discriminate between trans‐ and paracellular resistance, and the general principle of this technique is outlined. Second, the conductance scanning technique is presented, which discriminates horizontally between optically distinct parallel pathways over a wide range of spatial resolutions. Using this technique, it was shown that occludin – in contrast to the then prevailing opinion – is not irreplaceable to barrier function. Third, three‐dimensional confocal fluorescence imaging for depicting transepithelial transport processes is introduced. Using this method the transepithelial translocation of bacteria which generate focal leaks was discovered.